Compendium of Cable Yarding Production Equations

COMPENDIUM OF CABLE YARDING PRODUCTION EQUATIONS

Richard R. Aubuchon

A Paper

submitted to

Oregon State University

in partial fulfillment of the requirements for the degree of

Master of Forestry

Jun21982 ABSTRACT

This paper is a compilation of most of the recent cable yarding production equations generated by the Forest Engineering Department at Oregon State University. Additional production equations found in the literature review have also been included. Background information for each of the studies involved has been summarized.

Data is basically organized into a set of tables for small, medium, and large sized yarders. Each sheet in a set of tables contains a particular type of information, such as production data, equipment information, crew information, and physical characteristics of the sale area.

Guidelines on the potential use of the compendium and a dis.- cussion of equations as predictive tools is provided. A graphical summary was developed to assist the reader in locating an equation representing a particular set of conditions. APPROVED:

John O'Leary, Major Professor Department of Forest Engineering

eo .- Brown, Department of Forest Engineering

Marvin Pyles, Assi!ant Professor Department of Forest Engineering

fridQ1 Eldon Olsen, Associate Professor Department of Forest Engineering

Date Paper is Presented June 3, 1982 TABLE OF CONTENTS

Page

Introduction 1

Background 1 Objectives 2 Scope 2

II Organization of the Data 4 Basic Approach 4 Information Listed 4 Tabular Headings 5 production data 6 rigging and yarding configuration 6 crew data 6 time study data 1/3. 7 time study data 3/3 7

III Comments on Using the Compendium 8 Equations as Predictive Tools 8 Interpreting Particular Tables 10 production data 10 variables measured but not used 12 Combined" Equations Versus "Individual" 13 Equations

IV Reference Key 15

V Suggested Improvements in Future Research Papers 17 Background 17 Variables 17 lateral distance 18 volume 18 grundslope 19 chordslope 19 lead angle 19 Production Equations 20 Delays 21 Coments on the Study 22

VI Common Errors When Using Mid-Range Values 23

VII Obtaining Input Data 27

VIII Summary 28

IX Bibliography 30 Page

X Appendices Tabular Summaries 33

V Definitions of Variables Used in Regression Equations 129 Symbols and Abbreviations 135 Formulas for Computing Weighted Averages 136 INTRODUCTION

BACKGROUND

Numerous production equations have been generated from recent cable yarding time studies. Such equations can be quite useful in arriving at production rate estimates. Although many of these papers may be readily available, the effort required in developing a good familiarity with the conditions of each study can be another matter. A review of the lfterature did not disclose any summaries of recent production equations and their study conditions. Digests are available of production studies listing background information and production rates, but equations are not included (Yancy, 1980).

There are examples of "in-house" compilations of equations with a limited amount of background data attached, but these are not immediately available to the public.

In 1972, the Forest Engineering Department at Oregon State

University began a small wood harvesting research program. Research projects have included both clearcut and partial cut prescriptions; uphill and downhill logging; live, standing, and running skylines; a number of different carriage models and slackpulling options; and both full cycle yarding as well as prebunch and swing operations.

In addition, other research papers written in the department during this period have been concerned with medium and large yarders in a number of different cutting regimes and yarding configurations.

This paper is a compilation of the production equations generated by most of these projects. Additional equations obtained in the literature are also listed. Background information for each 2

equation is included.

OBJECTIVES

The intent of this paper is to provide a compendium of cable yarding regression equations to assist forest rnanayers and others in estimating yarding production rates. Specific objectives are:

Summarize the production equations and background information

of cable yarding research projects conducted at Oregon State

University in the Forest Engineering Department.

Summarize any other recent (1974 to the present) cable

yarding studies found during the literature review which

resulted in production equations and contained background

information about study conditions.

List suggestions for improving future research papers in

this area with the intention to make these papers more

understandable and useful to the reader.

SCOPE

The paper is intended to aid the forest manager in arriving at estimated production rates. The equations listed were developed under a particular set of circumstances and study conditions. Differences between the project area and the forest manager's site, as well as discrepancies among the parameters of each logging "show;' may result in large disparities between production rates predicted by the equation and actual rates of production realized on the ground. The summary of study conditions will provide some idea of how closely 3

the two "logging shows" match. The equations can be quite useful to the forest manager if their limitations are kept in mind, but strict reliance on equations alone could result in unreliable production estimates. ORGANIZATION OF THE DATA

BASIC APPROACH

The production studies and equations presented in this paper

have been sumarized in a set of tables organized by type of

information. Equations were initially segregated on the basis of yarder size: small, medium, or large. Small yarders have maximum

mainline pulls less than 25,000 pounds. Medium yarders have

maximum mainline pulls equal to or greater than 25,000 pounds and

less than 71,000 pounds. Large yarders have maximum mainline pulls

of 71,000 pounds and greater. A particular set of tables (e.g.,

small yarders) contains individual sheets summarizing the production

equations; variables measured during the study, but not used in the

equations; machine data of the yarding equipment used; rigging and

yarding configuration; crew information; physical data of the sale

area (e.g., topography, age and size of timber, species, density,

etc.); and time study information (e.g., values of parameters

commonly included in production equations). The tabular suiinriaries

are intended to provide the background information necessary for

the reader to compare study conditions of a particular equation

with the site conditions and circumstances of their own area.

INFORMATION LISTED

Only information presented in a reference was included in the

summaries. Assumptions concerning equipment specifications, crew

data, or any other study conditions were avoided. Although 5

specification sheets for many of the yarders used are available, information about line size, pull, drum capacity, etc., was not listed unless specifically mentioned in the paper. This same approach was used in filling out all the tables. The possibility of error by assuming normal or expected conditions precluded the use of any information sources other than the research paper itself.

If the reference does not indicate a certain piece of information, that block is left blank in the table. Items which have a value of

or "nones' in the study are listed that way in the tables.

Many of the tabular variables were subject to different interpretations by various authors0 Definitions were not constant.

Methods of measuring particular parameters differed. When additional explanation about a particii'lar value was needed or more information was available than could be accomodated by the table, footnotes were employed. The footnotes for a particular table immediately follow that sheet. The tabular sumaries and their footnotes appear in

Appendix A.

TABULAR HEADINGS

Most of the column headings for each of the tables is self- explanatory. Units of measure are also included in the headings.

Any abbreviations or symbols used in the tables are defined in

Appendix C. In most instances, if there is some discrepancy between the entry value and the column definition9 a footnote clarifies the point. There are, however, a few columns which require some discussion. Each table with column headings subject to interpretation will be discussed separately. Production Data

The majority of regression equations are for turn time in minutes, and this is the indicated unit of measure in the column heading. In addition, there are some equations which result in a logs/hour value rather than minutes/turn. When this occurs, the row entry for that particular equation begins with "logs/hr =

The variables listed in each production equation are defined in Appendix B.

Rigging and Yarding Configuration Data

Entries under the "yarding system used" column assume full cycle yarding. If the equation is for a pre-bunching or swinging operation, this will be specified.

Crew Data

Quite often crew experience was not discussed in the reference.

A distinction was made between regular logging crews and crews composed of researchers and graduate students. Given no additional information on crew experience, regular logging crews were entered under the "Experience" column as "commercial logging crews,1' whether they were working on normal logging production

sides or were involved in specific logging research projects.

Crews composed of researchers and graduate students were described as such. 7

Time Study Data 1/3

Chordslope values are taken from the landing. Therefore9 chordlopes for uphill yarding will be negative, while they1ll be positive for downhill yarding. Groundslope values are taken along the inhaul direction. Therefore, groundslopes for uphill yarding will be positive. Downhill yarding will result in negative groundslopes.

Time Study Data 3/3

Values entered under the "carriage height" column indicate the height of the carriage in feet above the ground at the hook point or position of lateral yarding. Deck height is defined as the height of the log deck at the landing. Any values entered in this column having a different definition are footnoted. The pre-bunched column indicates whether pre-bunched logs were being hswungsl or not. This column does not indicate the pre-bunching of logs. The value entered under the "total number of turns" column is the number of observations used to generate that particular regression equation. Any deviation from this definition is indicated by a footnote. 8

COMMENTS ON USING THE COMPENDIUM

This paper is a summary of recent production studies. It can serve as a central source of information on all the included research projects. However, if more detail is needed, the original article should be reviewed.

EQUATIONS ASPREDICTIVE TOOLS

Each of these equations were developed under a particular set of circumstances. For those specific conditions during that study, the equation may be a good estimate of production. However, when the equation is applied to another area, its ability to predict reliably should be viewed with caution. Circumstances cannot be identical. Physical parameters of the site will differ. Production can be affected dramatically by changes increw size and personnel

(Mclntire, 1981; Zielinsky, 1980). Differences will occur; and estimated production rates based entirely on a particular regression equation, even when conditions seem to be matched closely, may not reflect actual production with any degree of accuracy. These equations can be useful if they are treated as yet one more source of information available to the land manager. They can be used as an aid in comparing different alternatives. Too much reliance upon them in estimating production rates can lead to serious errors.

Most of the production studies listed in this paper have used a detailed time study procedure. During these studies, subcycle data are usually recorded to some fraction of a minute. The duration of detailed time studies is short when compared to gross

(shift-level) time studies. Detailed time studies tend to miss 9

seasonal influences and lengthy downtimes because of their small

time frame (Linjala, 1979). Dykstra (1976) has suggested that gross time studies may be more appropriate in appraisal work since the data may more accurately reflect total downtime. Curtis (1978) compared production rates determined from both detailed and gross time studies: both studies had analyzed the same systems (running skyline, inverted skyline balloon, highlead balloon, and heavy

helicopter). The rates measured by the gross time study were consistently lower. Curtis concluded that the gross time study more accurately reflected total downtime and, therefore, was better

suited for developing information useful for appraisal purposes.

Another point that should be remembered when using these equations

is the fact that most of them have been developed for a particular yarder model. Attempts to "fit such an equation to a similar model may prove unsatisfactory. Mann (1979) used a regression equation

developed for the Washington Iron Works 108 Skylok Yarding Crane

in a running skyline configuration to predict turn times for a

Madill 044 running skyline system. The equation overestimated

actual turn times by an average of 33%. Mann concluded that the use

of one regression model as a predictive tool for a wide-range of

running skyline yarders operating under different conditions is

questionabi e.

The ulimitsl of the study should always be kept in mind while

using these equations. Attempts to extrapolate the equation beyond

those limits can yield unpredictable results. Little confidence 10

should be placed in such production estimates. Applying a shortspan equation to a logging show requiring long horizontal spans is a futile exercise. Before using any of the regressions, compare the range of values of the study parameters with those of the proposed logging operation.

INTERPRETING PARTICULAR TABLES

Some of the information listed on two of the tabular summaries need additional explanation. Each table will be discussed separately.

Production Data

The 11% delay" column on this sheet is heavily footnoted because

of the numerous methods and interpretations used by authors

in calculating this value. There were basically two types of

variations involved: 1. differing total time bases on which

delay percentages were calculated, and 2. differing inter-

pretations of what should be considered a delay or how a delay

should be categorized (e.g., operational or non-operational).

When information about calculating % delays was listed in the

reference, it was included as a footnote appended to the entry

in the % delay column.

Many authors used as a total time base the combined totals

of productive time and operational delay time. Operational delay

time was then divided by this total time base for a percent

delay figure. Non-operational delays (many authors considered

major mechanical repairs to fall in this category) and skyline 11

corridor and landing changes where excluded from the calculations.

Other authors chose to include both operational and non-operational delays in their total time base while excluding corridor and landing changes. They would then divide either total delays or only operational delays by their total time base to arrive at % delay. Some authors made no distinction between operational and non-'operational delays. Still others added an additional category called experimental delays. The possible combination of these different delay categories when determining a total time base makes the delay % figure anything but straightforward.

To further compound the matter, there were several inter pretations on what constituted delay time as opposed to productive time. For example, resetting the chokers was sometimes considered part of the yarding cycle (productive time) and in other studies was categorized as a delay. Even when there was agreement about a particular item being a delay, the manner in which it was categorized and that category's inclusion or exclusion in the % delay calculations further clouded the issue.

It is hoped that the footnotes will provide enough background for the reader to correctly interpret these figures. Unfor- tunately, some authors did not provide many details concerning their delay % calculations.

While a reader may be interested in the procedure a particular study used to calculate % delay9 he should not assume the percentages will appTy to his own situation. Delays are not consistent, even for a specific yarding system, and a better 12

approach at estimating nonproductive time is to use local experience (Dykstra, 1976).

Variables Measured But Not Used In Regression Equations

Most of the entries listed on this table are given in descriptive terms rather than the variable form used in the regression equations. This approach was used to make the table more accessible to the reader and eliminate the need to refer to regression variable definitions. On occasion, the description of a variable was so involved that the regression variable had to be used instead. Definitions of all regression variables appear in Appendix B.

There were a number of reasons why variables in a study were not included in the regression equation. In some instances they did not meet the study's statistical criteria for inclusion.

This may be the result of the variable's limited range of values, rather than its inherent ability to influence production rates.

Also, human error in measurement or faulty sampling procedures could bias the variable against inclusion (Dykstra, 1975). At times a variable did meet the statistical criteria, butwas eliminated from the equation since it could not be easily measured and used for predictive purposes (e.g., a measure of the percent defect, Curtis, 1978; volumn per turn, Linjala,

1979). 13

"COMBINED" EQUATIONS VERSUS "INDIVIDUAL" EQUATIONS

Some of the equations listed use the combined data base of a number of different yarders. Sometimes the combined equations are

segregated by yarding direction (uphill versus downhill.) or system used (e.g., highlead versus grabinski) (Linjala9 1979). Equations may also be grouped by yarder size or some physical parameter of the

sale area (e.g., external yarding distance) (Gorsh, 1982). Estimating

production rates using either "combined" equations or equations

developed for a particular machine represent two distinct approaches.

Quite often the appraiser does not know which yarder model will

be used to yard a sale area (Linjala, 1979). A combined yarder equation may be the solution. Also, combined equations may be preferred when specific equations do not react well to those variables causing the greatest amount of variation in production rates (eg., crew performance) (Gorsh, 1982). The potential problem of estimating

production rates of one yarder model with a regression developed for a different yarder has already been discussed (Mann9 1979). Faced with this situation, a combined equation may, again, be preferred.

Curtis (1978) and Linjala (1979) tested the hypothesis that

combined equations in their studies could describe the data as well

as their respective set of individual equations. Curtis could not

reject the hypothesis at = .95 for any of the combined equations.

Linjala rejected the hypothesis at the .005 probability level for

all his combined equations and concluded that there is a statistical

difference between the individual equations and their respective

combined equation. The combined equation did not explain the data

as well as the individual equation. 14

Depending upon the circumstances of a particular sale, appraisers may find either approach (combined versus individual equations) appropriate. They should keep in mind the respective advantages and limitations of each method when making their selection. 15

REFERENCE KEY

To assist the reader in locating equations of interest, a graphical summary has been provided (Figure 1). Equations were first separated by yarding system; either skyline or highlead.

Skyline yarding was subdivided into standing, live, or running skyline systems. Equations for each of these yarding systems were then segregated on the basis of yarder model size: small, medium, or larye. A final subdivision was made according to the type of cut: either clearcut or partial cut.

A code was used to designate each equation and provide a link between the graphical sumary and the tables in Appendix A. Small, medium and large yarders were represented by the Roman numerals I,

II, and III, respectively. The Roman numeral is followed by a dashed line and the arabic number assigned to the equation as it is listed in the tables. Single spans, uphill yarding, and full cycle yarding are assumed for all equations in the chart. Deviation from these assumptions are indicated by one or more letters following the arabic number. Pre-bunch or swing yarding operations are designated by P or

S, respectively. Downhill yarding or both downhill and uphill yarding are denoted with the letters D and B, respectively. Multispans or a combination of multispans and single spans are assigned the letters

M and C, respectively. A legend with these designations is included on the chart. In instances where equations involved more than one category on the chart (e.g., both clearcut and partial cut, or both highlead and live skyline), the equation was listed under both designations. FIGURE 1 LOGGING SYSTEMS SKYLINE IIIGI1LIND STANDING I- LIVE RUNNING SMALL r MEDIUM LARGE SMALL MEDIUM LARGE SMALL I MEDIUM I LARGE SMALL MEDIUM CC PC CC PC1. CC 1. PC 1. CC 1. PC CC PC CC 4 PC4 CC PC I' CC J' PC 4 4CC PC CC PC I-6C 41/\ I-9CI-8DCI-1011I-4MI-3D 11-1211-2 11-15II-I4SM Ill-sIll-3DIU-2 Ill-3D111-2 1-5 1-241-23I-fl1-221-2 11-11 Il-lU Ill-I111-4 1-291-28I-lB 11-1311-911-3 I-RD1-7I-6D1-51-4 I-30P1-211-lOP Il-i I-12PM 1-25 /\ /\ 1-13 l-13PM 1-26 LL I-14P14 1-31 Ii I-15C /\ 1-32 /\ /\ I-16C 1-33 /\ I-20MI-19Cl-18Cl-l1C LEGEND: = Clearcut P = Pre-bunch Operation I-21C Arabic Nunder PC111=II = = LargeMediumSmallPartial yarder Cut yarder (Mainline(mainline (25000 lbspull S < mainline 25000 lbs) pull < 71000 lbs) 11000 lbs) CMBS1) == Swing BothLoggingIlultispan Uphill Operation operation (Intermediate & Downhill involved Yarding support used)Downhill Yarding a con1nation (e.g., 1,2,3 etc.)= Nun4er of the regression equation NOTE: configuration.fullUnless cycle indicated yarding otherwise,with singlespanl all and in an uphill of Multispan and Singlespan Yarding are for 16

Following is an example of how the chart could be used. If the reader was interested in equations for standing skylines operating in partial cuts and he believed that a medium sized yarder was adequate, there would be two equations available: II-14SM and

11-15. The letters included in the first code would indicate that this was a swinging operation and it utilized one or more intermediate supports. Yarding would be uphill. The other equation (11-15), since no letters were included in the code, would be for an uphill yarding operation with no intermediate supports. The logging show would be full cycle yarding, rather than a pre-bunch or swing operation.

By reviewing data listed for equations 14 and 15 in the medium-sized yarder tables in Appendix A, the reader should have a good idea of how well these equations fit his or her situation. 17

SUGGESTED IMPROVEMENTS IN FUTURE RESEARCH PAPERS

In reviewIng the studies presented in this paper, therewere a number of occasions where additional information or clarification would have made the equations more useful. If one of the objectives of the study is to provide the forest managersome means of estimating production rates, the following points should be considered.

BAC KGROUND

Enough background information should be included in the study report so that an individual can determine how closely the production equation matches his or her circumstances. Study dates, site location, sale area information, weather conditions,crew and machine data, yarding system information, as well as therange of parameters involved in the time study should all be included in the report.

VAR IABL ES

The variables included in the regression equation should be easily measured and applicable to most situations.Variables such as percent defect and volume per turn are difficult, if not impossible, to measure prior to actually yarding the area. These variables may be significant in explaining production variation, but their usefulness in an equation utilized for estimating production is questionable.

Variables should be defined precisely. Their units should be specified and the manner in which they are measured should be described.

This also applies to background data listed in the text. Some reports 18

described stand composition in percentages of different species.

However, the reader did not know if these values were in terms of stand volume or total stems per acre, or determined in some other manner. Volumes were often given, but the procedure or log rule with which they were calculated was not mentioned.

Standardizing the definition and manner of measuring commonly used variables would eliminate a good deal of confusion. Based upon the literature review, the worst examples of common variables having numerous definitions and disparate schemes of measurement are those

listed below.

Lateral Distance

Lateral distance has been defined as the slope distance per-

pendicular to the corridor from the first log hooked or the last

log hooked. In some studies, lateral distance meant the actual

slope distance the log traveled from hook point to corridor.

The length of skidding line from hook point to corridor was

another definition. Lateral distances were both estimated by

eye and measured. Pacing was also used. In a few studies,

a log lead angle and the log's perpendicular distance to the

corridor were manipulated to give an "actual lateral yarding

distance."

Volume

Volumes were recorded in board feet, cubic feet, and cunits.

A number of different log rules were used to calculate volumes. 19

Groundslope

Groundslope was always given in percent. However, authors used different sign conventions. A positive groundslope in one study would be recorded as a negative value in another study. Ground- slope was also recorded as an absolute value.

Chords lope

Different sign conventions were also used when reporting chordslopes. The unit used was always percent. For those equations which used a percent value of any parameter, no instructionwas given concerning the form of the value to be entered in the equation. The reader did not know if a percentage should be entered as a decimal or a whole number.

Lead Angle

Definitions for lead angles considered either a single logor the average value for a turn of logs. In some cases it was a deflection angle from the corridor, but dependingupon the author, the angle could be turned either uphill or downhill to the log. Another definition of lead angle was the angle formed by the winch line and a projected line travelling along the length of and through the center of the log. For one author, turning the angle in a counter-clockwise direction resulted ina negative

value. In that study, the range of lead angle valueswas +900 to

-90°. For all the papers reviewed, lead angleswere reported in degrees. 20

With so many different definitions for common variables,

there is a very real possibility that equations can be mis-

interpreted. A mistake made about the sign convention is just

one example. By standardizing the definitions of common

variables and agreeing upon one method of measuring them,

mistakes of this kind can be avoided.

PRODUCTION EQUATIONS

Most of the studies reviewed were detailed time studies. In some instances regression equations were developed for each of the defined cycle elements (eg., outhaul9 lateral outhaul, hook, lateral inhaul9 inhaul, and unhook). The total production time equation (full cycle yarding) would then be obtained by suming the elemental equations. For other studies, a total production time equation was developed separately. The study should specify which type of total time equation was developed.

Although none appear in this paper, some production equations created by combining elemental equations include cycle elements which do not always occur. The reader should be aware of this possibility and modify his or her approach because of this non-constant cycle element.

All production equations should have their cycle elements well defined. There should be complete understanding of exactly what the author considers to be productive time. Among the papers reviewed, an activity such as resetting chokers was sometimes included in a cycle element and in other studies it was considered a delay. 21

Exactly how an activity will be categorized should be evident to the readerS

DELAYS

The discussion on delays is similar to the coments about cycle elements. If delays are to be separated into different classes

(operational, non-operational, experimental, etc), the classes should be defined precisely. Examples for the different classes or categories of delay should be given. Exactly how are skyline corridor changes, landing changes, pre-rigging time, and major mechanical repairs handled? Are these items considered separately, or are they included in one of the standard delay categories? The reader should have no doubts.

The procedure by which delays and productive time are represented as percentages of total time should be thoroughly explained. Total time was defined in a number of ways among the studies sumarized in this paper. For example, one definition of total time was the sumation of productive time, operating delays, non-operating delays, and skyline corridor changes. Most studies excluded corridor changes.

A common definition of total time was the combination of productive time and operating delays alone.

Because of the different definitions of delays, delay categories and total time; it is difficult to compare percentage values among studies. Interpreting these values can also be a problem. If a set of standards could be agreed upon by researchers, the information about delays would be much more useful. Set categories and definitions of 22

delays, as well as one specific procedure to calculate percentages for productive time and delay time, would improve this section of the time study tremendously. The following are references that may be useful in standardizing terms and procedures: 1. Mifflin and Lysons,

1978; 2. Berrard, Dibblee, and Horncastle, Undated; and 3. Haarlaa,

1981.

COMMENTS ON THE STUDY

A section should be reserved in the research paper to comment on any complications or pecularities about the study that could influence the interpretation of results. Changes in equipment, personnel, or procedures during the project should be noted. Assumptions made by the authors should be specified. If necessary, a guide should be provided on how to interpret information contained in charts, graphs, tables, or any other summaries of data. 23

COMMON ERRORS WHEN USING MID-RiNGE VALUES

When mid-range values of independent variables are assumed to be the average values, and these values are used in the regression equation to estimate an average production rate, errors will result if either of two common conditions exist:

The regression has nonlinear terms, or

The independent variable has a nonsymmetrical (skewed)

distribution (Olsen, unpublished).

If either of these two conditions are present, a weighted average of each independent variable should be used instead of its mid-range.

Olsen (unpublished) has developed a method, using integral calculus, to determine the correct weighted average. A table listing his formulas for computing weighted averages of common nonlinear regression terms for two types of distributions (uniform and triangular) appears in Appendix D.. The uniform and triangular distributions represent the extremes normally encountered in logging applications.

The uniform distribution (symmetrical) would be appropriate for a slope yarding distance variable on a long, narrow corridor, since equal numbers of turns would be expected throughout the length. An example of the triangular (nonsymmetrical) distribution would be slope yarding distance on a circular setting where more turns will come from farther distances as the area yarded increases in proportion to distance from the landing. Variable distributions can be identified by analyzing production studies or they may be determined on the basis of logging engineering principles or past experience 24

(Olsen, unpublished). Given uphill yarding on a steep, clearcut slope, a nonsymmetrical distribution of slope yarding distances would be expected because of the tendency for logs to roll downhill after cutting, thus increasing the number of turns farther from the landing.

When the mid-range value is incorrectly applied, the resulting estimate can be as much as 50% in error. In most cases, the error is an underestimation (Olsen, unpublished).

- If a regression equation is to be used for predicting an average production rate, the terms of the regression and the distribution of the independent variables must be assessed. Given the proper formula for computing a weighted average and the end points of a variable's range, estimates can be correctly calculated.

A complete numerical example using one of the regression's listed, in this paper and considering the need for weighted averages of independent variables, appears below:

Numerical Example:

GIVEN: y = 5.102 + O97O (LOGS) +O.00000172(SYDIST)2+ 0.031 (LDIST)

- 0J94(CREW) (Hensel et. al., 1979)

where:

y = delay-free turn time estimate (minutes)

LOGS = number of pieces yarded per turn

SYDIST = the slope yarding distance (feet)

LDIST = lateral yarding distance (feet). Actual slope distance

the log travels from hook point to corridor.

CREW= the number of persons in the yarding crew. 25

Range of variables and actual average values (Hensel, 1977)

LOGS 3.50- 6.00, 4.87

SYDIST = 1000- 3000,1990

LDIST = 50 -150, 7

CREW = 4 - 5, 425

Yarding Conditions: Uphill logging with a Wyssen system -

Slopes range from 45% to 75%

Variable Distribution Assumptions Formula

"LOGS" - UNIFORM b(X1+X0)

(IISYDISTtI)2- UNIFORM b(X-X) 3(X1 -X0)

"LDIST" - UNIFORM b(X1+X0)

where:

b = coefficient

X1 = maximum value

X0 = minimum value

Comparing the true averages of "LOGS," "SYDIST,' and "LDIST" to their respective range of values indicated that a uniform distribution was the most likely. Given a triangular distribution, the true average for each variable would not have approximated its mid-range figure so closely. Normally, variable distributions will have to be determined based on logging engineering principles and past experience.

The distribution of the variable "CREW" was not considered. A whole number will be used rather than a weighted average sirce fractional loggers are hard to find these days. 26

This example will compare the actual average cycle time of the study to two estimates from the regression equation.The first calculation will use the true averages of the independent variables.

The second estimation will use weighted averages computed from the formulas in Appendix D with the exception of the variable "CREW."

In most cases, the second approach will be more appropriate when using an equation to predict cycle time for a proposed logging operation. The true average of the independent variables will not be known until logging has been completed. However, the appraiser will have a good idea of the -range of values for each variable on the proposed sale area. The formulas in Appendix D utilize this range to determine weighted averages.

The actual average cycle time in the study was 19.292 minutes

(Hensel, et. al., 1979). Using the true variable averages, the predicted average cycle time [E(Y)] is:

E(Y) = 5.102 + 0.970(4.87) +0.00000172(1990)2+ 0.031 (97)

0J 94 (4. 25)

= 18.820 minutes

Using the formulas in Appendix D and setting "CREW" equal to 4

(average number in the study was 4.25), the predicted average cycle time is:

E(Y) = 5.102 + 0.970(6.00 + 3.50) + 0.00000l72(3000 - l000) 2 3(3000-1000)

+ 0.03l (150 + 50) - 0.194(4) 2

= l9487 minutes.

If "CREWt' had been set equal to 5, E(Y) would equal 19.293 minutes. 27

OBTAINING INPUT DATA

Caution should be used when estimating or calculating values of independent variables. A clear understanding of the variable's definition will help eliminate potential errors. Special attention should be given to the sign conventions and units associated with each yariable. Time spent in accurately estimating slope yarding distance will be wasted if input is made in feet while the equation requires distances in stations. Groundslopes entered with the wrong sign convention will nullify any potential usefulness of the equation.

One common error involves estimating yarding distances from topographic maps. Keep in mind that measuring distances on such maps will only account for the horizontal component. If the input desired is slope distance, the average slopes over the area will have to be incorporated into the calculations to account for the vertical component. 28

SUMMARY

A number of production equations have been developed in recent years by researchers in the Forest Engineering Department at Oregon

State University. This paper is a summary of most of those equations.

Background information about the study conditions for each of the listed projects has also been included. Besides studies conducted at Oregon State University, any recent production equations found during the literature review were also included.

Data from the production studies was basically organized into a set of tables. Each table dealt with a particular type of information: production data (regression equations and delay percentages), independent variables measured but not used in the equation, machine data, rigging and yarding configuration information, crew data, physical data of the sale area, and time study data.

A section of the paper was devoted to guidelines on using the compendium. Equations as predictive tools was discussed. Comments were made on interpreting information listed in two of the summary tables: "production data' and "variables measured but not used."

The relative merits of using ucombinedu equations or "individual" equations were listed.

A graphical summary was developed as a quick reference for the reader and an example was provided on how it might be used and interpreted. The chart can easily be used in conjunction with the tabular summaries. 29

In reviewing the studies listed in this paper, there appeared to be a number of opportunities for improving the organization and conduct of future studies. Background information was sometimes insufficient. Comonly used variables had many different definitions and methods of measurement. Activities involved in the logging operation were considered either a delay or productive time, depending upon the study. -Different approaches were used in calculating delay percentages. Standardization would remedy much of the confusion. A section reserved in each study to discuss complications or peculiarities of the project and comment on interpretation of data would also help.

If an individual as3umes the mid-range value of a variable is the average value and he uses this figure in the regression equation to arrive at an average production rate, he or she may be in error. Nonlinear terms in the equation or a nonsymmetrical

(skewed) distribution of the independent variable will normallycause an underestimation of turn time. A method to compensate for this by using weighted averages is provided in the paper. The equations can also be incorrectly used if there are errors in calculating or estimating values of the independent variables. Inputing data with the wrong sign convention or units of measure will nullify any potential benefit of the equation. 30

Aulerich, D. Edward. 1975. Smallwood harvesting research at Oregon State University. Logger's Handbook, Vol. XXXV, 10-12, 84-88.

Aulerich, D. Edward, K. Norman Johnson, and HenryA. Froehlich. 1974. Tractors or skylines: what's best for thinning young-growth Douglas-fir? Forest Industries l0l(12):42-45.

Berard, Jean A., D.H.W. Dibblee, and D.C.Horncastle. (Undated) Standard definitions for machine availability and utilization. Logging Comittee of the Woodlands Section, Canadian Pulpand Paper Assoc. (In-house publication), index 2428 (B-l), 21-24.

Curtis, Richard J. 1978. Production rates of skyline, balloon, and helicopter yarding systems fromgross time study analysis. Master of Forestry paper. School of Forestry, Oregon State Univ. Corvallis, OR.

Dykstra, Dennis P. 1975. Production rates and costs for cable, balloon, and helicopter yarding systems in old-growthDouglas- fir. Research Bull. 18, Forest Res. Lab, School of Forestry, Oregon State Univ., Corvallis, OR.

Dykstra, Dennis P. 1976. Production rates and costs for yarding by cable, balloon, and helicopter compared for clearcuttingsand partial cuttings. Res. Bull. 22, Forest Res. Lab, Oregon State Univ., Corvallis, OR.

Fisher, Edward L., Harry G. Gibson, and ClevelandJ. Biller. 1980. Production and cost of a live skyline cable yardertested in Appalachia. In Process. USDA For. Serv. Res. Paper, Northeastern For. Exper. Sta., Broomall, PA, NE-465.

Gabrielli, Robert M. 1980. Cable thinning in young forests with average dbh of 5-8 inches: a case study. Master of Forestry Paper. School of Forestry, Oregon State Univ., Corvallis, OR.

Gardner, Rulon B. 1980. Skyline logging productivity under alter- native harvesting prescriptions and levels of utilizationin larch-fir stands. USDA For. Serv. Res. Paper INT-247, 1-34, Interrnountain For. & Range Exper. Sta., Ogden, UT.

Gorsh, Joseph. Regional Logging Engineer. Region 1, USDA Forest Service. Personal comunication.

Haarlaa, Rihko. 1981. Productivity measurement in logging operations: recommendations based on international practice. Harvesting Research Group, Div. of Forest Research, CSIRO, P0Box 4008, Canberra ACT 2600. 31

Hensel, William A., and Leonard R. Johnson. 1979. Operating characteristics and production capabilities of the Wyssen skyline system. Transactions of the ASAE, Vol. 22, No. 4, 724-730.

Hensel, William A. 1977. Wyssen skyline logging in northern Idaho and central Washington. Master of Science Thesis. School of Forestry, Univ. of Idaho, Moscow, ID.

1ff, Ronald H. 1982. Production of a small scale cable yarder in a southern pine thinning. (In process)

Keller, Robert R. 1979. Prebunching with a low investment skyline yarder in thinnings. Master of Science Thesis. School of For- estry, Oregon State Univ., Corvallis, OR.

Kellogg, Loren D. 1978. Downhill skyline thinning with the Igland- Jones Trailer Alp and Alp Cat carriage. (Unpublished.) School of Forestry, Oregon State Univ., Corvallis, OR.

Kellogg Loren D. 1976. A case study of prebunching and swinging - a thinning system for young forests. Master of Forestry paper. School of Forestry, Oregon State Univ., Corvallis OR.

Kramer, Brian W. 1978. The production performance of the Igland- Jones Trailer Alp yarder in clearcut northwest hardwoods: a comparative analysis of two cases. Master of Forestry paper. School of Forestry, Oregon State Univ., Corvallis, OR.

Linjala, Edward J. 1979. The analysis of highlead yarding time study data from southeastern Alaska. Master of Forestry paper. School of Forestry, Oregon State Univ., Corvallis, OR.

Mann, John W. 1979. Skyline logging production in the southern Sierra Nevada Mountains: a case study. Master of Forestry paper. School of Forestry, Oregon State University, Corvallis, OR.

Mclntire, John C. 1981. The effect of swinging and sorting with a skidder on yarding and loading efficiency in small diameter Douglas-fir. Master of Forestry paper. School of Forestry, Oregon State Univ., Corvallis, OR.

Miffin, Ronald W., and Hilton H. Lysons. 1978. Skyline yarding cost estimate guide. USDA For. Serv. Res. Note, Pacific N.W. For. & Range Exper. Sta., Portland, OR, PNW-325.

Neilson, Dennis A, 1977. The production potential of the Igland- Jones Trailer Alp yarder in thinning young growth norwest conifers: a case study. Master of Forestry paper. School of Forestry, Oregon State Univ., Corvallis, OR. 32

Olsen, Eldon D. 1981. Method to avoid two common errors in estimating logging costs with regression equations. (Unpublished) School of Forestry, Oregon State Univ., Corvallis, OR.

Pursell, W.W. 1979. A production study of the Peewee yarder during a skyline thinning operation. Master of Science paper. School of Forestry, Univ. of Washington, Seattle, WA.

Sherar, James R. 1978. Production rates and a comparative analysis of fuel consumption for a live, standing skyline, and highlead cable yarding system. Master of Forestry paper. School of Forestry, Oregon State Univ., Corvallis, OR.

Yancey, William F.. 1980. Comparison of rubber-tired skidder and skyline cable systems for Appalachian timber harvesting. Master of Forestry paper. School of Forestry, Duke Univ., Durham, NC.

Zielinsky, Cary R. 1980. Operational prebunching: a logger's application to reduce skyline thinning costs. Master of Forestry paper. School of Forestry, Oregon State Univ., Corvallis, OR. APPENDIX A I. PRODUCTIONSM/LL YIRUER: DATA MAXIMUM MAINLIME PULL 25000 lbs REGRESSION EQUATION - TOTAL TURN TIME (MINUTES) DELAY rulEI3ASED ON DELAY 'P COMMENTS 2.1. Pursell, 1979 RErERENcE + .00563.6144 (LEAUTURN)+ .00475 (5YUI5T) + .00053 (LDI5r)2+ .28694(LOGs) 61567 Yes111W 7 3. Itensel,Fisher, et et al, al, 1979 19R0 (101ST)l2.3J42.374 ++ .00841141 -0.385 0.945 (LOGS)f (CREW) (SYDIST) 0.00000062 + .72548570 (SYDIsT)2 (LOGs) + 0.0096 .254.40 Yes 3l. Z' consideredMoving the acarriaqe delay stop was 5.4. Kramer,Ilensel, 1978et al, 1979 0.68620(LOGS)(LUIST)5.102 + + 0.970-0.00525 0.017590.194 (LOGS) (CREW) (CII).(SYDIST) + + 0.02521 0.00000172 + 0.01243 (CHORDSLOPE) (SYDIST)2 (LDIsT) + + 0.27960 0.031 .670 28 Yes 20fi Includes a "RESET" element and 6. Kraiiter, 1978 (VOLUME)1.62970 + 0.32467 - 0.02040 (DKIIT) (CII) ++ 0.006240.00219 (LDIsT)(SYDIST) + 0.00320 .39 Yes l9. element"MOVINGIncludes SKYLINE in athe "RESET" yarding STOP CL.AUP" element cycle in 7. UnpublishedKellogg, 1978 (CHOKERS)1.66608 +.989382 + .00367794 (LOGS) (SYDIST) + .0217172 + .046098B (VOLUME) (LATDIsT) - 1.10751 .37 Yes orTimethe lines yarding spent or tintangl repositioningcycle ing chokers a 8. LJri.iublKellogg, ished 1978 + .00235821.27545 + (SYDIST) 1.36991 (LOGS) + .0111352 - 1.10802 (LDIST) (ChOKERS) + .0483455 (CII) .34 Yes orTimedelaysturn lines on spent the or deckuntanglingrepositioning considered chokers a 9. 1977 1.6932 + 0.005119 (SYDIST) + 0.025653 (LDIST) + 0.2783 (LOGS) .29 Yes 26.l© delaysturn on the deck® considered I. PRODUCTIONSMAlL YARDER: DATA MAXIMUM MAINLINE PULL < 25000 lbs. 10. Kellogg, 1976 REFERFNCE -2.8897 + .028864 (SYDIST) + .010653 (LANGLE) + .036543 REGRESSION EQUATION - TOTAL TURN TINE (MINUTES) R 2 DELAY FREEBASED ON TINE ? DELAY* COMMENTS 11. Kellogg, 1916 (VOLUME)1.0935 + .0040312 + 2.1101 (cHOKERS)(SYDIST) + .00519 (ZONE) + .0092485 .34.39 Yes ® 34.2 yarding"RESET" cycle considered part of the 12. Keller, 1979 (LOGS).907 + + .00837 (.218 x (VOLUI1) 10-5) (SYDIST)1 + .0119 + .00341 (LDIST) LATDIST) - .0142 (VOLUME)/ J 18.6 acarriageyarding delay cycle.stop was Moving considered the 13. Keller, 1979 + .458(BLOCK)(LOG)1.493 (BLOCK) + + .0288 (.177 (VOLUME) x 10-5) (SYDIST)2 + .00734 (LATDIST)+ .00491 (LDIST) - .0328 (VOLUME)/ - .0957 .346.415 YesYes 43.843.2 15.14. Mclntire,Keller, 1979 1981 (HOOKLOG)+.584083(LATDIST)2.951 + .00377 + .0034641.0665714 + .0117(VOLUME) (DKIIT)(SYDIST) (SIDIST) ++ .0178205.324 ++ .0152292 .014 (LOGS) (VOLUME)(cM) (LATDIST) + (.578 x 1O) + .427251 .4284.185 Yes ©52.2 50.0 "RESET" considered4O part of 16. Mclntire, 1981 .4502091 + .00282149 (SYDIST) + .0176626 (LATDIST) + .529121 I' timewasdelay part time. of yarding cycle "REPOSITION" 17. Mclntire, 1981 (IIOOKIOG) + .0564319 (DKHT) + .00736944 (vOLUME) .44 76 'S 19.18. Mclntire, 1981 .612107(IIOOKIOG).922269(HOOKLOG).037302 + .00296974.00275107 .0027979+ +.0256433 .0911757 (SYDIST) (SYDIST)(VOLUME) (DKHT)+ + +.00796932(VOLUME) .0182247 .0173265.011785 (LATDIST)(IATDIST) (LATDIST) + + .509236.449032 .499394 .4697.5212 I' 20. Mclntire, 1981 (IIOOKIOG).0741916(UOOKLOG) + +.00759683 +.00466162 .00188264 (VOLUME) (SYDIST)(VOLUME) + .0245706 (LATDIST) + .293742 .6675.4526 " 'S 21. Mclntire, 1981 (HOOKIOG)1.3969.0941052 + .00391347 (LDGcREW)+ .0151707 (SYDIST) (VOLUME) - .307468 + .0178717 (DMYSKID)- .381483 (LATDIST) (RIGGERS) + .429317 - .5369 'S 01: DELAYExcludes FREE yarding TIME IREGRESSION road changes, EQUATION) computed as TOTALiODUC1IVE TIME + TOTAL DELAY TIME TOTAL DELAY TIME total turn time (excluding yarding road changes) = e.g., D.F.T. = 6 minutes (Tio - 00 Delay %) T.T. 6 6.397 mInutes DelayAverage % production time per cycle was 7.13 mInutes. = 6.2% 100 - 6.2 With delays average cycle time was 9.20 minutes. (3) withExcludes normal yardingyarding roadoperations changes were and Included.delay times the author attributed to the experimental nature of the study. All delays considered to be associated Average delay free turn time was 4.375.03 mInutes.minutes. With delays, average turn time was 5.736.85 minutes.mInutes. TotalValuetime. studybased timeon a composedtotal study of cycletime oftime 8700 (average minutes 4.48 which minutes includes for both549 observations),thinning (this operationalstudy) and somedelay clear time, felling experimental operations delay (not time in and this road study). change logsofCycle 10safelyturns, sorttime -7 rigging elements:21%inhaul, of -turns). 8 operator 1position outhaul (7% Toccurred2 sortof turns), rigging-choker when 11 a sortturn deckhadsetter to(Involved be(untangling positioned the operatorchokers on the 32%flatteningdeck of before turns), down It 3 could thelateral deck be unhookedout,or moving 4 hook, - logs16% 5 oflateralto enable In, landing 6 reset additional - turns), 9 unhook, 23% Excludedof Includedthe yarding time in spent delaycycle timein when moving were the resets,sIngleelement drum sortingis scheduledwinch chokers to toa new orliegin, rigging,location. repositioning transit delays a turn when of alogs choker on setterthe deck wasn't for unhookingIn position and to side execute blocking a basic a ele,iient turn to usingeitherAuthor the freepresents combined or avoid production data a hang-upbase equatIons of duringall his for Inhaul. other different equations. crew sizes wIth and without swing skIdder. lie refers to this equation as the "combined" equation (V-) 0 FOOTNOTES Excludes yarding road and landing changes and pre-rigging. (continued) Separate regressionsOne were portion: made for two portions of the cycle and added together. inhaul, reposition, unhook outhaul.Iuthor states that thisOther model portion: is sufficient for either carriage type used in this study: The model is for a haulback assisted prebunch yarding cycle. outhaul, lateral outhaul, hook, lateral thhaul Igland-Jones multispan carriage or Christy gravity . PRODUCTIONSMAIJ_ YARDER: DATA MAXIMUM MAINLiNE PUll < 25000 lbs. REFERENCE REGRESSION EQUATION - TOTAL. TURN TIME (MINUTES) R 2 MSED ON 22. A'ilerich, 1975 0.826 + 0.006 (SYDIST) + 0.032 (EDIST) + 0.897 (L.OGS) .56 DELAY FREE YesTIME? DELiY COMMENTS 24.23. Aulerich, 1975 1.2101.925 ++ 0.0020.009 (SYDIST)(sYDIST) ++ 0.0170.015 (EDIST) (DIsT) ++ 0.9090.253 (L.OGS)(LOGS) .32.45 Yes 25. Aulerich, et al, 1974 6.3210.7603 - (10G5)0.6972 +(CREW) 0.0095 + (SIOP[)0.0062 (SYDIST)- 0.0522 +(TI) 0.0320 (L.DIST) + .58 YesYes 9.0''3J©© (j yarding"RESET" cycle notconsidered considered part ii of delay the 26. 1FF, 1982 + 0.000691.054 + (WEIGHT)0.00234 (SYDIST) + 0.01180 (L.DIST) + 0.980 (L.OGS) .127 to .76' a Yes 56.l cyclechainconsidered"RESET" chokerstime anddelays, © considered"MOVING untangling STOP" 28.27. 1FF, 1982 1Ff, 1982 1.3111.751 + 0.004390.00358 (SYDIST)(SYDIST) ++ 0.012570.01257 (L.DIST)(UflST) ++ 0.000240.00035 (WEIGHT) WEIGHT) .140 to.34 Yes 56.3 "RESETS"considredde1ays 29. 1FF, 1982 1.090 + 0.00530 (SYDIST) + 0.01257 (L.DIsT) + 0.00037 (WEIGHT) .1401S3Jto .S3i Yes 26.04l.3 "RESETS" considered de1ays 31.30. Gabrielli,Zielinsky, 1980 2.1832.321651.2112 + (LOGS).00248+ 0.0154 (SYDIST) (L.ATSD) + +0.00662 0.00157 (SINANG) (SDIST) (LATDIST)+ 0.9976 (CREWI) + .3566.4332 Yes 20 çaxi: 33.32. Gabrielli, Gabrielli, 1980 1980 1.13052.2838.13111 + .00304(1065).00267 +(SYDIST)(SYDIST) .01263 (VOlJJME)7.++ .00526.03435 (SINANG)(VOL.UME)© (LATDIST) + .2094.4378 YesYes 22.6®®21 fXD 0 co FOOTNOTES Excludes landing and road changes. TotalRangeMoving cycle ofthe R2 timecarriage for equationindividual stop determinedwas cycle excluded element by fromsunmiing equations delay individual time which and were cycle yarding added element time to forminequations. this total study. cycle time equation. Moving the carriage stop accounted for 9.1Z of total time. operatingandPercentagesValue repair is delay total delays, listeddelaytime. planning belowpercentage are delays based based and on onpersonnel total total yarding scheduled delays, time but operations which excludes is the time yarding sum which of roadtotal includes changeproductive total times. cycletime, element Examples of operating delays are: resets, repositioning logs, yarding road changes, changingpre-bunch spars, block changes, total operating delay time and total non- time, operating delays, maintenance delaysand repositioning and mechanical drum failures. setto facilitate line spooling. Total productive time = 53%. V (13 + t Examples of non-operating delays are breaking line, line fouledOperating on the delays drum, personal 32%. Non-Operating delays = 15%. Volume calculated by Smalian's formula: where: L =tbv ==length basalcubic ofareafoot the volume in log square in inside feet feet bark at the smallbasal end area of the in logsquare feet at the large end of the log ® Valuethat(carriage),transitchanges, normallyis totaltinie landing niechanical delayfor would a changes chokerpercentage not (yarder-lines),occur andsetter hadexperimentalbased out not of onan personal, position totalexperimental delays turn toand are time. move excluded.other. study to thebeen correct in position, Total turn time is theExperimental sum of all operational delays were delay definedOperational time as and the yardingdelaytime required categories cycle tune.due are: to the researchersprogress. or the study landing delays, repositioning a turn on the log deck, mechanical moving the carriage stop, resets, sort rigging, Road 0 Operationalof1n lateraladditional outhaul, delay operational time hook, was anddelay recorded inhaul besides tofor build movingthose listed the carriage in footnote stop #8 only if up a turn of logs. was "bunch". no other activity, typically unhooking, was occurring. "Bunch" is defined as any time required over and above one cycle I. SMALL YARUER: MAXIMUM MAINLINE PULL < 25000 lbs VARIABLES MEASURED flUT NOT USED IN REGRESSIONREFERENCE EQUPiTIONS: FisherPursell, et 1919al. 1980 Weightlateral per yardingturn, chordslope, distance. volume per turn, logs per acre by thinning block. IlenselIlensel et etal, al, 1979 1919 Kramer,Kramer, 1918 1918 DistanceNumberchoker skylinesettersof pieces stopper per turn. moved, turn, accumulatedchordslope, sumnumber of logsof choker per turn setters on a perdeck, turn. volume of logs per turn, number of 1. Kellogg, 1918, unpub. Nellson,Kellogg, 1911 1918, unpub. CarriageVolume/turn,lead angle height, (angle lead ground anglebetween (angleslope skyline %,between number and logskyline of pathintermediate andduring log lateralpath supports, during inhaul), numberlateral carriage of inhaul), choker height, logsetters deck log used, height.deck volume,height. number of Kellogg,Keflogg, 1916 916 Numberpre-set oflogs choker setters, number of chokers used. number of chokers used, log deck height. Keller, 1919 Carriagelead angle. height above the ground, SIDIST, groundslope %, slope direction with respect to outhaul direction, lead angle. Mclntire,Keller, 1979 1981 leadyardingfctual angle. lateraldistance, yarding fll0CK distance, lead angle, groundslope lead angle. %, slope direction with respect to outhaul direction, slope 1. SMAIk YARDER: MAXIMUM MAINLINE PUU < 25000 lbs. VARIABLESliclntire, MEASURED 1981 BUT NOT USED IN REGRESSIdN EQUATIONS: Lead angle. Mclntire, 1981 Leadlead angle. Mclntire,Mclntlre, 1981 leadLead angle.angle, deck height. Aulerich, 1975 Aulerich, et al, 1974 1982 Groundslope-- %, slope from top of tower to carriage, slope along lateral yarding directiol)EJBH. 1FF,1FF, 1982 GroundslopeGroundsiope %, slope from top of tower to carriage, slope alongalong laterallateral yarding direction, DBH, pieces per turn. yarding direction.DBH, pieces per turn. Zielinsky,1FF, 1980 1982 HeightGroundsiopeheight. of block %, slopeon pre-bunching from top of spar, tower LANGIE,to carriage, number ofslope chokers along used,lateral pieces yarding per direction,turn, volume 0811, per piecesturn, logper deckturn. Gabrielfl,Gabrielli, 1980 lateralCubiclog footlead yarding volumeangle, distance, percarriage turn, pieces heightlog leadper above turn,angle, the log carriageground. lead angle, height carriage above the height ground. above the ground. FOOTNOTE areAuthors not speciried.mention that other variables were considered but not Included because of their small effect on R2. The other variables I. MAChINESMAIi YARDERS: DATA (1 of 2) MAXIMUM MAINLINE PUll < 25,000 lbs. YARDER CARRIAGE TOWER DRUM PUll/SPEED/CAPACITY (KIPS/FPII/FT) YARDER SPECIFICATIONS 51/Mt /SI'/HBlINE SIZE 1. REFERENCEPursell, SOURCE 1979 Peewee MOUft MODEI Pee Wee MODEI SKYI INE -- 6.qL75O/26OJD MAINlINE 4.S/lSO/26OdDSUCKPUUING 9.O/l59/26O(P FIAIWBACK (INCHES) 3.2. tlensel,Fisher,19791980 et al WyssenEcologge,® W-9 MakiStandardmaticWyssen Auto- Ecologer 23.4/750/- 8.'95O/l54O 5.4. Flensel,Kramer,1979 et 1978 al WyssenTrailerIg1and-Jones W-9i Alp Christy JonesIgland- -/400-1000/3300 -/400-1000/1800 -/400-1000/1800 ,'/-I1l- , /-/,%/ - 6.7. UnpublishedKellogg,Kramer, 1978 1978 II JonesIgland-Iglan - JonesIgland- -/400-1000/3300 -/400-1000/1800 -/400-1000/1800 /4/-/. 8. Kellogg, 1978 IS II Alp Cat IS IS II 9. Neilson,Unpublished 1977 JonesIgland.© II SI -/400-1000/2600 -/400-1000/1800 -/400-1000/1800 11.10. Kellogg, 1976 Mini-YarderBantamSchield-T-350 MakiNone None -/-/1000 -/-/9009/120/316 -/-/1600 //-/j 1. MICI11NESNAIl YIRDERS: t1f1A (1 0f z) MIXJMUM MAINIANE PUll < 25,000 lbs. YARDER SPECIFICATIONS REFERENCE S0URCI YARDERMODEI CARUJAGE MODEI MODEITOWER SKYLINE DRUM PUll/SPEED/CAPACITY (KJPS/FPM/FT) PIAINUNE SIACKPUEI ING HAUU3ACK S/M/SP/IIfllINE SIZE (INCHES) 12. Keller, 1979 Igland-Jone ,p Igland-Jones JonesJgl and--/-/2000-3000 -/400-1000/1800 -/400-1000/1800 14.13. Keller, 1979 Trailer Alp IIti U Christy II II -/-/2000-3000 -/400-1000/1800 -/400-1000/1800 ;; / / 15. Mclntire,Keller, 1979 1981 IColler I, & ChristyKollerJgland-Jones SKA I II I Koller,, II -1-11100-1-12000- 3000 -/-/1100-/400-1000/1800 -/400-1000/1800 --/4 / - 18.17.16. Mclntire, 1981 I, IIUI III, I I,II II -1-11100-/-/1100 -1-11100- 1-11100 // - / - / -I - 19. Mclntire, 1981 SI II ,, 19" II II -1-11100 -1-11100 /Z / -/ - 21.20. Mclntire, 1981 'SI, I, I, II II III -/-/1100 -/-/1100 >d,//-/- I. StlAU VAUDERS: MAXIMUM MAINLINE PUll 25,000 lbs. MACHINE DATA (z 0fz) YARDER SPECIFICATIONS CARRIAGE SPECIFICATIONS REFERENCE INTEUI_OCI( TOWER HEIGHT (FT) WE IGIIT( ut) IATERAI CAPABftIIY UNESOPER. POSITION HOLDING CIAMP STOP CAPACITY 2.1. FIsher,Pursell,1980 et ilil al NoneHydraulic 42.037.0 600 x x x 4.3. Jlensel,Ilensel,1979 et al None x x 11000 lb 6.5. Kramer,Kramer, 1978 1978 None 23.723.7 35/8 158 x x x 11000 lb4 8.7. UnpublI(ellogg,UnpublishedKellogg, istied 1978 1978 None 23.7 x x 11.10. 9. Neilson,Kellogg, 1977 1976 None None23.7 35186D x- x x 14.13.12. Keller, 1979S11 None 23.723.7 x IIda.A. x Clii ,sty x I. MACHINESMAll YAROERS: DATA (2 MAXIMUM MAINlINE PUIk - 25,000 lbs. f z) YAROER SPECIFICATIONS CARRIAGE SPECIFICATIONS REFERENCE INTERIOCK TOWER (IF IGHT (FT) IATERAI CAPABftITY () LINESOPER. POSITION HOUflIIG CLAMP STOP CAPACITY 15. Mclntlre, 1981 None 22.97 WEIOIIT(Ik)330 x x 1 Tor 17.16. Mcjntjre,Mclntlre, 1981 None 22.97 330 Xx X 1 TorTot 19.18. Mclntlre,Mclntlre, 1981 1981 None 22.97 330 xx x 1 1 TorTot 21.20. Mclntlre,ticlntire, 1981 None 22.97 330 x x 1 Tor IOOTNOTES MountedBaseDrum of half onDrum. 130-horsepower full. tree farmer CD skidder, yarder equiped with remote electronic controls. TwoRated Igland-Jones at 6680 horsepower. carriages used, one for singlespan and one for multispan. PowertoadSinglespan capacity. unit was carriage/multlspan John Deere 2640 carriage. 10 horsepower farm tractor. FlaulbackRadio1600 controlled 1bs.).janufactured line was single rigged drum by laterally winchModern contained toLogging pull the onEquipment, mainline a sled and Inc.out powered from the by carriagea 47 horsepower Volkswagan industrial engine (machine weight ("squirrel" block attached to the end of the haulback - PowerPeeweeand the source yardermainline is prototype a 60was horsepower pulled mounted through gasolineon John the Deereengine. "squirrel" JD 640 block.). cable skidder (110 horsepower at 2200 RPM). I. MI\CHINESMAU VPRDFRS: DMA (1 0f 2) M!XIMUM MAINlINE PUll < 25,000 lbs. DRUM PUlL/SPEED/CAPACITY (KIPS/FPM/FT) YARDER SPEC 111CM IONS UNE SIZE 22. Aulerich,REFERENCE 1975SOURCE 5chie1d-ant.jn YARDERMODEl RossCARRIAGE MODEl MODElTOWER SKYlINE MAINlINE SIACKPUIIING None IIAUL.RACK SL/MIJSP/Hfl (IflCUES) 23.24. !u1erich, 1975 1-3 50 " " CarriageMki Iog None 25.26.27. Aulerich1FF, 1982 efcI.,fl7't flockSingleChristyRoss -1-11000 None -/492/600-/-/900 NoneNone -1-11300-1-11600 28. in, 1982 (1) CarriageflockDoubleiglandUsed None -/492/600 None -1-11300 //-/. 29.30.31. Gabrielli,Zielirisky,1FF, 1982 1980 Skagit SJ2-R ChristyNone" " None-- None -/492/600 None -/-/1300 32.33. Gabrielli,Gabrielli, 1980. 1980 YarderMobil Thinning " " Christy None I. MACHINESNAIl YARUERS: DATA MAXIMUM MAINlINE PUll < 25,000 lbs. (2 f 2) YARDER SPECIFICATIONS CARRIAGE SPECIFICATIONS REFERENCE INTERlOCK TOWER UEIGIIT (FT) WEIGIIT(Ik ATERAI CAPARILITY ii'U) LINESOPER. POSITION HOIIJING CUVIP STOP CIPICITY 22.23. Iu1er1ch,Iu1erich, 19751975 None x x 21.26.25. Iu1erichet.l.,I7yIu1erich,1FF, 1982 1975 NoneNone 12 170 xx x x 28.27, 1FF, 1982 None 12 x x 31.30.29. ZlelInsky,1FF, 1982 1980 None None 6OJNo Carriage Involved. x x X 33.32. GabrIelli,GabriellI, 1980 4040 6O x Xx IOOTNOIES Two-speedIgland Skagit 4000/2 GU-lO winch drum mounted set poweredon a Holder by a A55-F350 cubic rubber inth tired, Chevrolet articulated V-B engine. logging tractor with a 12 foot tower. (Capable of deliverinl 175 horsepower). The entire 2 drum yarder. Mid-drum,unit was mountedlow gear: on the back of a dump truck. High gear: 23.811.75 KLPS/245 KIPS/500 F.P.M./llOO r.P.M./lloo feet feet Only one of the two drums was required for pre-bunching. 300Only pound one ofChristy two drums carriage used hadin this3/4's pre-bunching steel plates operation. added to increase weight to 600 pounds (aided Ho information given on second drum. gravity outhaul on relatively flat chordslopes). I. RIGGINGSMALL Y/RD[R: AND YARDING CONFIGURATION DATA MAXIMUM MAINLINE PULL < 25000 lbs. REFERENCE SYSTEM USED YARDING DOWNHILLUPHILL/ SI NGLESPAN/MULTI SPAN GRAPPLECIIOKERS/ SWINGING BOOM? YesYARDER HAS No COMMENTS 2.1. Pursell, 1979 Running Skyline Genera 1lyUphill Singlespan Chokers X 0 3. llensel,Fisher, et al, 19801979 live-GravityStandi ng-Wyssen Outhaul DownhUphill ii P Singlespan Chokers X 5.4. Hensel, et al, 1979 Stand i ng-Wyssen Uphill Multispan Chokers X 6. Kramer, 1978 RequiredStanding-ilaulbackLive-Gravity Outhaul line Uphill DoSinglespan ChokersChokers X 0 7. Kellogg, 1978 Standing-Ilaulback DownhillUphill Multi spa IP Chokers X 8. tlnpublKellogg,Unpublished ished 1978 PullsStandruns 1Slack ng-Iiaul back Downhill Both Chokers X 10. 9. Neilson,Kellogg, 1977 1976 SingleLineStanding-Haulback Required Drum Uinch- Uphill NotBot4 applicable Chokers Not applicable X 11. BunchingRadio Controlled9 to the Corridor Pre- Chokers X 12. Keller,Kellogg, 1979 1976 StandingSwingingLive-Gravity - from Outhaul, the Corridor Prebunch® Uphill MultiSinglespan span Chokers X 13. Keller, 1979 toStanding Corridoreorridor Pre-Bunc1 Uphill Mul t I span Chokers X 0 I. RIGGINGSMAU YARDERS: AND YARDING CONFIGURATION DATA MAXIMUM MAINLINE PUll 25000 lbs. YARDING UPIIILL/ SINGLESPAN/ CHOKERS/ SWINGING BOOM? YARDER Hi't NO COMMENTS REFERENCE SYSTEM USED DOWNHILL MULTISPIN GR/PPLE YES X 15.14. Keller, 1979 toStandIngPre-Bunch Corridor Uphill Multispan Chokers X 16. Mclntire, 1981 GravityStanding Outhaul Skyline Uphill Both® Chokers X 17. Mclntire, 1981 StandingGravity SkylineOuthaul Uphill Both® Chokers X 18. Mclntire, 1981 GravityStanding Outhaul Skyline Uphill Both® Chokers X 19. Mclnti,e,Mclntire, 1981 1981 StandingGravity Outhaul SkylineSkyline - Uphill floth® Chokers X 20. Ilclntlre, 1981 GravityStandingGravity Outhaul Outhaul Skyline - UphillUphill MultispanBoth® Chokers X 22.21. Mclntire, 1981 GravityStanding Outhaul Skyline Uphill Both® Chokers X X 23. Aulerich, 1915 LiveManual Skyline Slackpull with Haulback- Uphill Singlespan Chokers X 24. Aulerich, 1915 ManualLive Skyline SlackpullSlackpull, - No Haulback, Self Uphill Singlespan Chokers X 25. !ulerfch,1914 et al, ManualLivelocking Skyline Slackpulling Carriage with Ilaulback Uphill Singlespan Chokers X I. RIGGINGSMAIJ YARDER: AND YARDING CONFIGURATION DATA MAXIMUM MAINI_INE PULl < 25000 lbs. REFERENCE SYSTEM USED YARDING DOWNIIftLUPHILI/ SINGIESPAN/MUITISPAN GRAPPLECFIOKERS/ SWINGING ROOM? YESYARDER PMS NO COMMENTS 26. Iii, 1982 NoChokers,OuthaulLive Ilaulback Skyline..Gravity Carriage, Manual Slackpull, Chain Uphill Singlespan Chain Chokers X 27. 1FF, 1982 ManualChokersCapabilityIlighlead,.LateralInstead Slackpull, ofusing Butt Cable Block Rigging, Uphill Singlespan Chokers X 28. 1FF, 1982 Slackpull,BlockRunning Carriage, Skyline To Manual - Double Grapple Uphill Singlespan Tow Grapple X 29. 1FF, 1982 ChokersSlackpull,BlockRunning Carriage, Skyline Cable Manual - Double Uphill Singlespan Chokers X FOOTNOTES Yarder Is uphill. Gravity, with yarder acting as a brake, is used to lower logs downhill to the landing. 42 skyline roads - multispan, 3i skyline roadsroad - single span. - singlespan. positiontoIn theIgland-Jonesmultispan landing during waslateral not required,outhaul carriage and the was lateral haulback used andinhaul. wasn't manual used. slackpulling was required in this pre-bunching operation.1* tie-back line was substituted for the haulback to maintain the carriage Since inhaul and outhaul ThemechanicalsinceChristy intermediate logs gravity clamp).were beingouthaulsupports pre-bunched carriage had to be wasat lowered theused corridor. and in manualorder to move the carriage past the supports. The skyline had to be lowered to release the clamp each time the carriage was moved to a new pre-bunching position. Carriage was locked to slackpullingthe skyline "stop"required ("stop" in this attached pre-bunching to skyline operation. by means of a Inhaul and outhaul not required andtousedThis the Jtopre-bunching regarding endassist of the these haulbackoperation two and carriagesused the both mainline applythe Igland-Jones herewas pulledas well. throughmultispan the carriage squirrel and block. the Christy gravity outhaul carriage. slackpulling. The haulback was rigged laterally to pull the mainline out from the carriage. Except for manual slackpulling, the conv,ents in I "squirrel" block was attached The hauilback line was (43 102 skylineskyline roadsroads -- singlespan,singlespan, 6 skyline roads - multispan. 1 skyline road - multispan. 3 skyline roads - 2 intermediate supports, 2 skyline roads - 1 intermediate support. ofMinimum2 span (horizontal)landing width was was 1011 115 feet.skyline roads - 1 intermediate support, Maximum landing width was 190 feet. 1 skyline road - 2 Intermediate supports, Minimum length of span (horizontal) was 432 feet. 1 skyline road - singlespan. Maximuii, length TallholdsI tallholds are outside inside thethe unitunit boundarIes,boundaries. 2 tailholds inside the unit boundaries. FOOl (continued) 2 uiian3%In uphIll.terms crew: of cordslope,13 of the corridors were downhill and 5 corridors were essentially flat. yarder operator and choker setter, no swing skidder. Slopes rangedtrom 22% downhill to 43 man crew: yarder operator,yarder chaser operator and and2 choker 2 choker setters, setters, no swingno swing skidder. skidder. 43 man crew: yarder operator,yarder operator, 2 choker chokersetters, setter and skidderand skidder operator operator to swing to swing and sortand sortlogs logsaway awayfrom fromthe yardingthe yarding area. area. aAuthor'sS manchaser) crew: "combined"and a variable equation: which indicates the presence or absence of a "swing" skidder on the landing. yarder operator, chaser, 2 choker setters and skidder operator to swing and sort logs away from the yarding area. independent variables include the number of choker setters, landing crew size (yarder operator with or without I. RIGGINGSMAll. YARUE: /NU YIRI)ING CONFIGURATION DATA MAXIMUM MAINLINE PULl < 25000 lbs. YARDING UPHIII/ SINGIESPAN/ CIIOKERS/ SWINGING ROOM? YARDER NA$ Zielinsky, 1980 REFERENCE Skylineon2-Speedto flack Pre-Runch ofCorridor,Drum Dump Set Trucklogs MountedManual to Used the SYSTEM USED UphillDOWNHIll MULTISPAN Singeispan ChokersGRAPPIE YES xNO COMMENTS D Gabrielli, 1980 OuthaulUveSlackpulling. Sky11ne-Gravit$ J , ® Self-Clamping Uphill Singlespan ChokerP X Gabrlelfl, 1980 OuthaulLiveCarriage. Skyline-Gravit ®, Self-Clamping Uphill Singlespan Choker X Gabriellj, 1980 Carriage.Outhaul®Live Skyline-GravIt Se'f-Clamping Uphill Singlespan Choker X Fool NOTES CD Two landings in this study: landing 21 was 0.080.1 acres.acres. CD corridorspar.alonglineThis waspre-bunchingthe tostrungcorridor the nextdown yarderedge. pre-bunchingthe corridorwas positioned spar.and through on the a landingblock attached approximately to a choker Thiswhere procedure orthe strap swing washung yarder repeated in thewould pre-bunchinguntilall later be logs located. spar that which were wasto besituated bunched to the spar were yarded. line was manually pulled out to a turn of logs and the turn was then yarded into a deck at the pre-bunching The rigging was then moved down the The pre-bunching CD ThreeThree preset chokers ring and chokers sliders and were a toggle used. hook were used. CD LogsSix ringwere chokerscold decked and aand toggle loading hook occurred were used. after the yarder moved out. Using the yarder's swing capability, a deck was first built on CD lengthyarderthe roadofin spansthe behind corridor. (horizontal) the yarder. ranged from 620 feet to 930 feet, the average span was 802 feet. When there were more logs than a deck on the road could hold9 the remaining logs were decked in front of tue I. CREWSMAtI DAT!YARDERS: MIXIMUM IiAINIJNE PUII < 25000 lbs. REFERENCE SOURCE H0OKTENDER OPERATOR YARDER SlINGERRIGGING CREW SIZE BY POSITION OPERATOSKIDDER 6 SETTERChOKER CHASER TOTI EXPERIENCE 3.2.1. Ilensel,Fisher,Pursell, et1919 al. 1980 et a!, 1919 1 2 4.5 3 None 5.4. tlensel,Kramer, 1918 et a!, 1919 Max.Mm. 12 4.25 machineCrew unf8nliliar with new 6. Kramer, 1918 Fun.Avg. 1.47 1 1. tinpublKellogg, ished 1918 Avg.Max. 1.31 2 Crewmachine unfamiliar with new 8. Kellogg,Unpublished 1918 Crew"downhicarriage."downhill"carri8ge. unfamiliar 11" before. before. with new NeverNever worked worked 10. 9. Kellogg,Neilson, 19111916 Max.Mm, 2 2 or machine.UnfamiliarnewCrew machine. unfamiliar with new with 11. Kellogg, 1916 0 0 0 Avg.Max.Mm. 121.2 1 3 or 4 I. CREWSMALL DATA YARDERS: MAXJIIUM MAINLINE PULL < 25000 lbs. REFERENCE SOURCE HOOKTENDER OPERATOR YARDER SLINGERRIGGING CREW SIZE BY POSITION OPERATOFt"SKIDDER CHOKERSETTER CHASER TOTAL EXPERIENCE I?. Keller, 1979 0 1 0 0 0 3 Yarding technique was new 13. 0 1 0 0 0 3 Yardingto the crew. technique was new 14. Keller, 1979 1979 0 1 0 0 0 3 Yardingto the crew. technique was new 15. Mclntlre,Keller 1981 0 1 0 0 1 0 2 Crewto the unfamiliarcrew. with new 16. Mclntire, 1981 0 1 0 0 2 0 3 Crewyarder unfamiliar and carriaqe. with new 17. McIntire 1981 0 1 0 0 2 1 4 yarderCrew and unfamiliar carriage. with new 18. McIntire 1981 0 1 0 1 1 0 3 Crewyarder unfamiliar and carriage. with new 19. Mclntire, 1981 0 1 a 1 2 0 4 Crewyarder unfamfliar and carriage. with new 20. Mclntire, 1981 0 1 0 1 2 1 5 yarderCrew and unfamiliar carriage. with new 21. Ilclntire, 1981 0 1 0 0 or 1 1 or 2 0 or 1 yarderyarderCrew and unfamiliar and carriage. carriage. with new FOOTNOTES Crew paid hourly. I sinqie choker setter operated for 75% of the turns observed. OneStudy man performedconducted alltwo yardingweeks after functions. machine was delivered to yarding crew. UsedPre-bunching to keep landingoperation-choker clear by sortingsetters andperformed decking both logs hook along and the unhook road. tasks. crewSkidderIndependent operator variables "chased" In at production the landing equation when he Include: 1 (yarder operator) or 2 (yarder operator and chaser)), and was free of his other duties. a) number of choker setters (1 or 2), b) c) presence or absence of swing skidder. presence or absence of chaser (landing I. CREWSMAll DATA VARDER: MAXIMUM WUNUNE PUU < 25000 lbs. CREW SIZE flY POSITION 22. Aulerich, 1975 REIERENCE SOURCE HOOKTENDER OPERATOR YARDER SUNGERRIGGUIG OPERATORSKIDDER CHOKERSETTER ChASER TOTAI EXPERiENCE 24.23. Aulerich, 1975 - 4 Departittent,ofCrew the consisted Forest O.S.U. Engineering of personnel 25. Au1erich et al, 1974 1 12 ID 2 Coni,uercial logging crew. 27.26. 1FF, 1982FF, 1982 0 0 0 1 0 2 Inexperienced. 29.28. 1FF, 1982 0 00 0 1 0 2 Inexperienced. 31.30. Gabrie11iZielinsky, 1980 1980 0 1 01 0 2 0 43 ConinercialConiuercial logging crew crew® 32.33. Gabrielli, 1980 0 1 1 0 4 CornercialConinercial logginglogging crew FOOTNOTES Chaser doubled as a skidder operator to swing logs from the landing to the loading deck. withOneDoubled chokersix ii,onths assetter chaser. had two years woods experience. rigging experience, The other choker setter alternated between the owner (good experience) and a man A thirdasYarder the crew fourthoperator member crew and wasmember. rigging the same slinger throughout were partthe study,owners workingwith about either 10 yearsas the logging choker experience,setter or chaser. the last couple of years with the SJ-2. All of the crew had at least a few years of logging experience. Three different people worked I. PhYSICALSMALL YARDERS: DATA or SALE AREA MAXIMUM MAINLINE PUll < 25,000 lbs SIZE OF UNIT ININVOLVED STUDY GENERAL SHAPE TOPOGRAPHY(5IOPE/ SIZE OF AGE ACREVOL/ DENSITY STEIIS/ LOCAT ION 1. Pursell,REFERENCE 1979 (ACRES) 44.7 Retangular OF AREA SteepTerracesBROKEN Slopes OR and NOT) TlThrT = cal TIMBER = 10" (YEARS) ;;= SPECIES 23OO(ft) (MBF) ACRE 200 COMMENTS Pack Forest, Pierce OF STIJI)Y 3.2.. hlensel,1980Fisher, etet al 62.0 Retangular 15 1nche -- Washington/IdahoMarion,JeffersonCounty, Western Virginia N.F. nearWA Area S.4. Kramer,llensel,1979 1978et al 4.64 Irregular NearSmall Ridge Draw 35-40 BigRed LeafAldeç 234 BentonSpauldingWashington/Idaho Co., Tract, OR Area 6. Kramer, 1978 1.32 Irregular ConvexPronouncedlop Break 35-40 Maple " II -- BlodgettColumbia Tract Co., Forest OR 8.7. UnpublishedKellogg, 1978 IS15 RectangulatRectangulat ConstantGroundslope4O% SlopeIl Il II McDonaldMb.n4"lJ C,pvfthhlS.Forest ror.st OR 10. 9. Nellson,Unpublished 1977 Irregular ConvexPronounced Break UBJ1Height = 14.1" 85' 35-40 firDouglas- " " 5060(ft3) 226 McDonaldColumbiaBlodgettCorvallis, Co.,Tract Forest,OR OR Forest Il. Kellogg, 1976 2.76 35-40 Il II 4824(ft3) 221.4II II II Corvallis, OR 1. PUYSICALSMAIJ. YARDER5: DA1A OF MIX1MUM MAINLINE.PULLSALE AREA 25,000 lbs. REFERENCE SIZE (ACRES)ININVOLVED STUDY OF UNIT GENERAL SHAPE OF AREA BROKEN OR NOT) TOPOGRAPHY(SI0PE/ SIZE OFTIMBER (YEARS) AGE SPECIES ACREYOu(MBF) DENSITY STEMS/ACRE COMMENTS 01LOCATION STUDY 12. Keller, 1979 58.24 250'CorridorsRectangular wIde 27-53 I1 6601(ft3) 195 County,Forest,Blodgett ColuinbfaOR Tract 13 Mclntire,Keller,Veller 19811979 1979 6558.2458 2A ' " Slopes10-20% Gentle 1H= ll 4jiii) 20-4027-53 t1jtI 5000(ft3)" 245®195 lI Paul Dunn Forest Mclntire, 1981 iaII iiH HI, II II II II 20-40 I, II IIII,' H Benton Co., OR Mclntire, 1981 U H BI I II I. 20-40 II II III'll IS Mclntire, 1981 ,,I, 0II ,,H II I II pII 20-40 II I II Mclntire, 1981 II II ,I I II UI 20-40 041 I, II II II,, FOOTNOTES The average diameter (average of small and large ends) of the harvested logs with a minimum top diameter of 8 inche,Averaqe length was 34 feet. TimberPrimarily harvested basswood, was blackpurchased and yellowas fire birch, salvage. red and white oak and sugar maple. Cutting prescription called for a selection cut. Smaller amounts of ash, hard maple and cherry. Average logscaling volumelength diameter per= 26.4'. acre Inside in cubIc bark feet.= 10.1" AverageFormula scalinglog used length todiameter calculaterwas: Inside bark 22.0'. Vlum V = (0.001818) (1)[D 9.6". + D + (Di) where: D1 VI = small end d,i.b. Inlargelog inches lengthvolume end d.i.b. Inin feetFT3 In Inches UncutTotalSeven areatreatmentcorridors of study. coversfanshaped approximately from one landing. 50% of the total area. Area divided into S different yarding techniques plus an uncut treatment for a total of six different treatments. Remaining two corridors parallel the last corridor In the fan-shaped set. Area specific to this production equation is a portion of the remaining acreage. Topography required intermediate supports.(Douglas-fir) = 16.7" HEIGHT (Douglas-fir) = 88.4' logging corridors had northeast or southwest aspects. iiIiUU11JiBil (total(Western merchantable Hemlock) = 12.0"conifer) = 13.8" HEIGHT (Western Hemlock) = 79.1' FOOTNOTES Approximately 38% Douglas-fir and 62% Western Hemlock by volume,(continued) some Red Alder. ValueTotal iarea of study - only a portion used for this production equation. for fir component only. UnderstoryApproximately vegetation 80% fir wasand a20% salal hardwoods - swordfern by volume. association. Speciesw.e Douglas-fir, 6rand fir, fligleaf Maple and Pacific Madrone. RasedSmalian on rulenumber was of used stems; to calculate95% Douglas-fir, volumes. 3% Red Alder, .015% fllgleaf Maple and .005% Western Red Cedar. I. PhYSICALSMAll YARD[RS: DATA OF SALE AREA MAXIMUM MAINLINE PULL - 259000 lbs. SIZE OF UNIT INVOLVED TOPOGRAPHY VOL/ DENSITY 22. Aulerich,RE FEREF4CF 1975 (ACRES)IN STUDY GENERAL SHAPE OF AREA BROKEN OR NOT) (SLOPE/ SIZE OFTIMBER = 10" (YEARS) 35AGE Douglas- SPECIES ACRE(MEW) STEMS/ ACRE COMMENTS Western Oregon OF LOCATIONSTUDY 24.23. Aulerich, 1975 I''I I' 35 fir pp Western Oregon Aulerich, 1975 Slopes3OZt, 50 I, 35 to 40 10 pp pp CorvallIs,McDonald ForestOR 25.26. Au1erichtI,8971FF, 1982 95 TerracesSlopes15%to 3O OBII =I' 8" 6"-20" 35 ShortleafSlash Pine 150 Waverly, Alabama 27. 1FF, 1982 Cross Slopes,I ii , p. ii Pine pp 'p I, 28. 1FF, 1982 'I I, II II Op SOI' 30.29. Zielinsky,1FF, 1982 1980 26.6 SettingsFanshaped I' U=l7"p. I, II 6Oto9O ® 93.7w 70'p Linn County, OR 31. Gabrielli, 1980 13.58 Ui= , 52500 48 'p Grande Ronde, OR p. p, 32. 13.58 Op 33. Gabrielll,Gabrielli, 1980 13.58 p. ,, ,p '5,,"H 'p 00 p. FOOTNO I ES ® CUnit3/tcre excessDataTwo was unitsof segregated60% in inmiedlately the study. by slope below classes the landings,of 20% and flattening 40%. out to less than 25% about Both have northeast to northwest aspects. In both units skyline corridor profiles are characterized by slopes in one third of the way down the slope. MerchantableMain merchantable sterns species (over 6" is dbh). Douglas-fir. Total number of trees (over 1.5" dbh)per acre was 1091 Western Hemlock accounted for 0.4% by volume. © MeanAverage dbh of elevation merchantable Is 2000 stems feet.above (over 6" meandbh). sea level. Mean dbh of the total stand (over 1.5") was 5.7". East aspect. Slope averages 40%. SpeciesAverage mixof dominantwas 48% Westerntrees in Hemlock9 this uneven 45% Douglas-firaged stand. and 1% WhIte fir. UnderstoryCubic feet/acre. consisted of vine maple and scattered Pacific yew. Board feet/acre = 17850 (based on conversion factor of 3.42 board feet per cubic foot). Soil was a Holocomb silty clay loam SoilScribner. is from theTyee sandstone formation. L TLMESMALL STUDY YARDERS: DATA 1/3 MAXIMUM MPUNUNE PULL. < 25000 lbs. thinning[c.c., partial, below/ TYPE 01 CUT SL.OPE YARDING LATERAL YARDIN6 CIIORDSL.OPE GROUNDSL.OPE 1. Pursell, 1979 REFER[IICE Thinning - L.og L.engthabovetree length, etc] wholetree Sumer 1978 DATES OF STUDY MINDISTMICE (FEET) 1072 MAX AVG486 MINDISTANCE (FEET) MAX AVG2? MIII-29 MAX +2 AVG MIN-3 FVX422 AVG 3.2. Ilensel,Fisher, et al 19791980 et al TreeClearcut - Generally ength 1977 - - - 700 1468 369 80 4. Hensel, 1979 et al Fire Salvage-Selection Suniner 1977 0 365 1990 148 0 160 97 -50 54 6. 7.5.Kramer, Kramer9Kellogg 1978 1978 Unpublished 1978 Clearcut Suniner 1977 200 10 950520 448367 00 345110 33.8 41 -16.4 -36.0 -26.4 8. Ke1logg Unpublished 1978 Thinning-L.ogThinning-Tree L.engthlength JuneSeptl97JtoSept 1979 l978to 60 970 492 l7 57.9 2 Kellogg,Neilson, 19771976 Thinning-L.og L.ength WinterWInterSuitmier 1976 1977 0 650 178224 76 0 140 41 10 - - - 70 25 Kell.e,Ke11r,Keller, 1979 Ihinning-loglhinningtogThinning-L.og L.engthL.ength L.enqth SumerSunmerSuniner 19781978 1978 251020 880807900 379.1319.3365.6 lO®l5®l 14JDl3dl3 64db 63.155. 0 443231 10.613.012.3 I. SMAll YARDERS: TIME STUDY DATA MAXIMUM MAIN1IUPU11 < 25000 lbs. L/ [c.c., partial, TYPE OF CUT Mclntire, 1981 REFERENCE Thinning-log lengthabove,thinning wholetree below/ length, etc] Sunner 1980 DATES OF STUDY MINDISTANCE (FEET)SLOPE YARDING MAX AVG MINDISTANCELATERAL YARDING(FEET) MAX AVG MIN C1ORDSLOPE MAX AVG MIN GROUNDSIOPE MAX AVG 11. Mclntire, 1981 Mclntire, 1981 Thinning-logThinning-Log lengthLength SumerSunnerSuniner 198019801980 Mclntire, 1981 Thinning-log length SumerSuniner 1980 1980 0 790 314.3 0 200 36.' Q I. TIMESMALL STUDYYARDERS: DATA MAXIMUM MAINLINE PULL 25000 lbs. REFERENCE MIN PIECES/TURN AVG PER PIECE (lId Ft) GROSS VOLUME AVG PER TURN GROSS VOLUME. (lId Ft) INTENSITYIFIINNING 1.2. Fisher,Pursell, et 1979 al MAX 2.6 MIN MAX 9jD MIN MAX AVG 21JD 200/163 (8ErORE/AFTER) (Stems/acre) 1900 . 1.35 52. 4. 3.Ilensel, Ilensel, et etal al 1979 2.82 --- 168 5. Kramer, 1978 1979 1 4 1.464.81 l6.5 76. 853 24.O 7.6. Kellogg,Kramer, 19781978 1 3 1.44 l5,8 311.6D (i 54. 22. 1 4 8. Kellogg, 1978 UnpublIshed 1 4 1.76 2.9'lO8.'3O.OT" ifl (I Approximately 50% Stem Removal 9. Neilson, 1977 Unpublished 1 4 1.621.92 2jD4.64"77.6X'24.64" 6O.ôI rn i' 21.oD rn Approximately42% Stems Removed 50% Stem Removal 11.10. Kellogg, 1976 2.81.3 42.3f'2O.6 39%36%37% VolumeStems RemovedRemovedRemoved 12. Keller, 1979 1 4 1.8 3.0 44.4 12.4 3.rJD 69JD 211) 36% Volume Removed 14,13. Keller, 1979 1 3 1.41.6 2.12.0 86.863.8 13.413.2 3,1D2.(P 87.P 17,) 72.6' 19JD I. TiMESMAU. STUDY YARDERS: DATA IiIXIMUM MIUNL.INE PUI.L < 25000 lbs. UEFERENCE MIN PIECES/TURN MAX AVG PER PIECEMIN (Rd Ft) GROSS VOLUME MAX AVt PER TURNMIN tROSS VOLUME MAX (Rd Ft) AVt INTENSITYTHlNNlNt Piclntire,Melntire,Mclntire9Mclntlre, 1981 ® e36%e36Z36% Stem StemStern RemovalRemoval Mclntlre, 1981 0 5 1.87 JJD 77.23j' ® (36%36% StemStem Removal FOOTNOTES Volutute given in cubk feet. PerpendicularStudy dates not distance given into article,skyline corridorarticle submittedNOT the actual for publication lateral yarding 1978. distance. YarderSingle swingingdrum winch pre-bunched pre-bunching logs logs in theinto skyline skyline corridor corridor. up to the landing. of TheseFromthe studycruise are generalarea. data: values for the entir 33% of stems removed, 23% of volume removed. study area Data used to Using data from the logging study, volume removed wasgenerate estimated this at particular 18'!. production equation came from only a portion LoggingFigure appliescrew consisted to the firof O.S.U.stems only.students that worked on weekends and during school breaks. I. SMIUi YARDERS: MIX1tIUtI 1/3tII1NUNE PULl < 25000 lbs. TIME STUDY DITI TYPE OF CUT Aulerich, 1975 REFERENCE Thinning [c.c.,treeabove,thinning parta1, length, wholetree below/ etc] DATES OF STUDY MINDISTANCE (FEET)SLOPE YARDING MAX AVG MINDISTANCELITERI1L YARDING (FFET) MAX AVG MIN CHORDSLOPE MAX AVG MIN GROUNOSLOPE I'VX AVG Aulerich,Iulerich, 19751975 Thinningrhinning Jan.Dec. 19751974 to 290 95 120 31 Iulerich,1FF,1974 1982 et al Thinning SprIngSuniner 19791972 10 154 310.7 98.9 --- 5 73 49.232.6 11 54 19.6 1FF, 1982 ThinningThinnthg SprIngSpdngSpring 1979 342240 184220168 127.2120.4 95.2 53 117107 59 42.328.525.8 842 212114 10.216.2 5.8 Garbrielli,Zielinsky, 1980 1980 Thinning LateSept.lug.1979 Summer9 30, - 1979 190 0 890750 379.3575.9 010 214150 92.7539.2 70 - - - Gabrielli,Gabriellf, 1980 Thinning Late1979 SunvnerSuniner 2510 675700 376.3345.9 0 193.2127.3 49.054.7 I. TItESMAU_ STUDY YIRDER5: DMA MAXIMUM MAINLINE PULL < 25000 lbs. PIECES/TURN PER PIECE (fld Ft) GROSS VOLUME PER TURN GROSS VOLUME (fld Ft) INTENSITYTHINNING 22.23.24, Iu1er1ch,AulericI,,!ulerIch, 1915 REFERENCE MIN MAX IVG2.3 MIN MAX AVG MIN MAX AVG Approximately 50% Steiii Removal 26.25. 1FF. Aulerch, 1982 et al 191 1 --- 3 1.642.53 51D 91 229f 80 28.21. 1FF, 1982 1 2 1.08 919/D 21O9' 3OOt 72671p: 29. 1FF, 1982 1 52 1.04 9/ 320w 52 37% Sten Removed 30. Ziellnsky, 1980 1 6 2.143.0 1 .3O.54 40%19% Volumeof Merchantable Removed Sterns Reuiioved 33.32.31. GabrIelli, GabrIelli,GabriellI, 1980 1980 2 1 97 5.33.23 6.880.14O.12.4f88.923.64 40% of Merchantable Sterns Removed FOOTNOTES ThinningCubIc foot Intensity volume wasranged 12.3. from 35% to 55% of the No "yum" yarding included. merchantable stenis (8" - 12" 0811). BeforeValue\fter Isthinning, turn thinning, weight the thestandestimated stand averaged averagedfrom 15volume approximately cunits/acre. equations. 7 cunits/acre. Value given in cubiccunits. feet. No "yum" yarding involved. I. TIMESMILL STUDYYPRDFRS: DATh 3/3 MIXIMUt1 MAINLINE PULL 25000 lbs. CUTTING ANGLELOG LEAD (0) hEIGHT (FT)CARRIIGE FIEJGIIT (FT) DECK PRESENT TOSKIDDER PRESFNTLOADER CFIOKFRS # OF PRE-BUNCHED ChOKERSPRESFT TOTAL YARDING TOTAL I. Pursell, 1979 REFERENCE IIerringIbn. I'/1TERN MIN MAX AVG MIN MAX AVG MJN IIAX VG CLEAR DECK? Yes YES x lO FLOWN 3 YES NOx YES x lO TURNS 196 ROIDS 18 1979Densel,1980Fisher, et al No Sometimes - x x 120 9') Kramer,1979Hensel, 1978 et al No - x xx 451110 -- 6 UnpublishedKellogg,Kramer, 1978 1978 0 135 6.0 42.0 3t 27.0 0 14 5.6 No 3- xx x 311150 53 8 Neilson,UnpublishedKellogg, 19771978 I1errthgboieIIrringhone 3J 1814 10 6 4835 21 ! 1 --- No-- x 3 x x 549250 47 Kellogg, 1976 ------28i 17.5 ------N/ N/A x x x 113207 100 Keller9 1979 Skyline45C Lead to ------1lO.ó X Keller, 1979 Skyline45CCorridor Lead to 12080045.8012 12 39 21.2 2 x Xx 170198 20 Keller, 1979 CorridorSkyflne45° Lead to 200200 9905250 9504460 10 4740 20.821.6 --__ 2 x x 468 3020 I. TIMESIIAIJ STUDY DATA YARDERS: MAXIMUM MAINLINE PULL < 25000 lbs. RErERENcE PATTERNCUTTINI3 MIN AN3LE106 LEID (°) M/X AV MIN HEIlIT (Fl)CIRRIA6E MAX AV MIN HEIGHT (Fl) DECK MAX AV CLEARPREStNT DECK? TOSKIDDER YESPRESENTL0IDER NO CHOKERS FLOWNfi OF PRE-RUNCIWUYES NO YESChOKERSPRESET NO 1011W ft TURMS YARDING ROADSTOTIW 15. Mclntire, 1981 WhenCorridor45°Skyline Possible lead to No 3 16, Mclntire, 1981 WhenCorridorSkyl45° Leadthe Possible to No ij 3 Mclntire, 1981 WhenCorridorSkyline45° Lead Possible to No Mclntire, 1981 WhenCorridorSkyline45° Lead Possible to Yes Mclntire, 1981 WhenCorridorSkyline45° PossibleLead to Yes 3 Mclntire, 1981 WhenCorridor45°Skyline Lead Possible to Yes Mclntire, 1981 When450CorridorSkyline Lead Possible to 0 16 IOOTNOTES Number of cycles upon which average times of phases and delays in the yarding cycle were based. flumberExpected of range chokes of pervalues cycle at rangedbeginning from of I study.to 2, with an average of 1.58. Variablelog,togs preset(e.g., measured pera 90° cycleis leadthe ranged angleangle froiiiformedimplies 0by tothat the 1, thewinchwith log an line isaverage atand aof projected 0.14. line travelling along the length of and through the center of the right angle to the winch line.). AnglesAngleskyline. themeasured turn ofwith logs reference forms with to athe line skyline. parallel to the corridor. Angles measured from the skyline and rotate in the downhill direction toward the log turn. 0° indicates the turn is parallel to the skyline. Sighting was made down the log and always pointing toward the landing. At 90°, the turn is perpendicular to the NumberbeAngles rotated offormed chokers toward by theusedthe line corridoraveraged of sight in1.4. a andcounterclockwIse line parallel direction,to the corridor. a negative angle results. Possible range of angles is +90° to 9O0. If the line of sight must thereVariableNumber were of measured chokers5 machine isused locationsthe averaged number and of2.0. 10"settings". "settings". A setting refers to a spar tree and all the material yarded to that tree. in this study ValueValuecorridor. is isthe the lead number angle of at skyline which acorridors turn of logson which is yarded. this system was used to pre-bunch logs. Angle is measured as a deflection angle from th* direction of the skyline Self-loadingPresence or absencelog trucks of skidderwith Crown is oneSuper of 3000the independentself-loaders variables were used. in the production equation. I. TIMESN/Ui STUDYYARDERS: DATA M/XIMUM MlINIiNE PULl 25000 lbs. REFERENCE PATTERNCUTTING MIN ANGLELOG LEAD (0) AX AVG MIN hEIGHT (IT)CARRIAGE MAX AVG MIN HEIGHT (Fr) DECK MAX AVG CIEARPRESENT DECK? TOSKIDDER YESPRESENTIOADER NO CHOKERS FIOWN OF PRE-8UNCHEDYES NO YESCHOKERSPRFSET NO TOT!W # TURNS Y!RDING RON)ST0T!I Aulerlch,Aulerich, 1975 et al RandomherringboneRandoiti Thinnun Thin 1FF,1974 1982 Yes 685 s43)24 -- ) .Gabrielli,llellnsky,1FF, 1980 1982 1980 HerringboneRandom - Angle 0 140 0 10 No x 2 x 151 5fD ) CorridorFrom the 0 104l.:J 20 40 35.2 No x 3 x x 160 1 GabrIelli,Gabrielli, 1980 .4S°HerringCorridorFromFlerringt,one Angle the bone 0 l05l.4 10 35 29.1 No x 3 197 I c.IS° AngleCorridorFrom the 0 9d35i 13 15 50 28.2 No x 6 x 87 1 FOOTNOTES (D AuthorSingle-log, states that3-pronged adjustable tow-grapple chain chokers,used instead with ofrings chokers. attached to the hook end, were used in an attempt to preset chokers. NumberTotal of yarding turns usedroads tofor calculate the study delay area. percentages. Author does not mention the number of roads involved in this equation. ® ThisskiddingThese is avalues pre-bunch line weremeasured deckmeasured alongto the as the nearestthe skyline angle 5 degreesbetweencorridor. ina linethe horizontalformed by theplane. prolongation of aline through the axis of the log and the lead or the AngleThis equationis measured is foras apre-bunching deflection anglelogs tofrom the the corridor. skyline corridor to the inhaul path of the logs. Operation did not involve yarding any pre-bunched logs Angle is turned looking toward the landing. thei'is.Iues. andby cycleSix themselves,hooking chokers of lateralcycle werethese was outhaul,used logs1.38 in would minutes. thishook be system.and bunched lateral into inhaul the sameto build full aturn. turn was classified as "bunch delay". If there was a turn that had empty chokers and a few logs situated so they would not make a full turn This occurred on 14% of the turns. The average time for the second lateral Time required over and above one II. PRODUCT IONMEDIUM DATA YARDERS: MAXIMUM MAINLINE PULL 25,000 < 71,000 lbs. DELAY FREEBASED ON RFIERENCEDykstra, 1975 3.69533 + 0.00287968 (BFVOL)0 REGRESSION- 0.0040344 EQUATION - TOTAL TURN TItlE (MINUTES) (UFVOL)0/(LOGS) + R TJME? DELAY % COMMENTS 0.00169959 (SYDIST) R=.169 to .27 Yes 15. washaulbyTota! ulaterallssunuiiing included andtime unhook equation movementin theseequations-any obtained or4 chokers outhdul, hook. in- Dykstra, 1975 0.002146493.8610! (SYDIST) + .0.001693482 (BFVOL)° - 0.0021163 (BFVOL)°/(LOGS) + R.214 to .33tI Yes elemental equations II 4.3. Dykstra, 1975 2.392!90.001842373.08932 (SYDIST) 1 + 0.0019426O.0009!426 (CIIORDSLOPE) - 0.11478 (BFVOL)0 - 0.0010625 (RIGGERS)0(BFVOL)0/(LOGS) + + R=.l01 to .30 Yes isfi 6A I. +0.00211976 (SYDIST).0.000863135 +Q.0118565 (BFVOL)'4-'(LOIST) - 0.000397724 (BFvOL)U/(L0GS) + O.0Q463 (LOGS) R.151 Yes 27P haul,haulsunwingTotal and timehook, unhookouthaul, equation latera! equations. !ateral obtained inhaijl, out- in-by 5. Gardner, 198(P LN(1T) (.001)(o.0o896) (WEIGHT) = 1.458050 + (.00l)(O.486540)(SYDIST) + .001145 (LDJST) .34 Yes 14.4' recentflaterial1/3 or dead moreremoved: logs sound. to 5" top, Green and ci) 6. Gardner, i98R -LN(TT) 0.000032 (SLOPE) (VOL) = 0.676830 + .000240 (LOGS)(LDIST) + .132343 LN(SYDIST) .44 Yes UI 8.7. Gardner, 198( 1N(T1)0.1918321N(TT) LN(SYDIST) = 0.6891340.580136 - .003076 (SLOPE) + +.002647 (LDIST) (.0000l)(o.400174) (LOGS)(WEJGUT) + .337807.001928 LN(SYDIST)(LDIST) + + .68 Yes 26i23fr) 9. Gardner, l98J U1(TT)(Vo)-(o.001)(o.00O545)(5YD15T)(.353655)(o.0000l )(LOGa(WEJGHT) 1.089454 + .019567 (L0S) + +.000043 (LDIST)(SLOPE)0.001065 (SYDIST) + .000617 .48.32 Yes 8.26.4 -c'J co 11. MEDIUM YlRDERS I'RODUCT ION DAT/S MlXIMIJM MIUNUNE PUll 25,000 < 71,000 lbs. REFERENCES REGRESSION EQUATION - TOTAL TURN TIME (MINUTES) P 2 DEI.P.Y flASED ON TIME? FREE DELAY % COI$tENTS 10. Gardner, l9BdZ) (IDIsT)LN(TT) + 1.812551(.0000l)(o.277323) (LOGS) (WEIGHT) + .000940 (SYDIST) -.00950(SIOPE) + 0.001721 .4? Yes 27." 1/3recentMaterial or moredead removed: sound.logs to 5" top, Green and 12.11. CurtIs,Gardner, l971 l98O 10G5/HRLN(TT)(LD1sT) - = = 1.910023-5.5364.4162 (LOGS) + 17.981+ 00p545 (SYDIST) - (IOGS) - 0O6795 (SLOPE) + 0.002118 .41 Yes 29.0© " 15.14.13. Curtis, l978 Keller, 1979 2.16410G5/I1R + .147 (LANDLOG) + .00281 (SYDIST) + 10.283 + 15.157 (LOGS) - 2.5147 (AYD)0.77521 (AYD) .23 (CHOKERS) + 0.18561 (CHORDSIOPE) .266.67.43 YesYes 25.28.110.' 00 Keller, 1979 (SYDIST2)(CHOKERS)2.77 + .0222 (VOLUME) - .0492 (VOLtJMEf(1OG5)+ .0364.463 (SINANG)(CII) + .000144 (LATDIST2) + .634 (.243 x 1O (HOOKIOG?j ) .565 Yes 25.2- FOOTNOTES The constant for this equation includes the average of several "events" IN toas= Naturalraiseseparate and log yardinglower the events. skyline. This Includes the time for the rigging crew to approach and that were isolated by the study crew but are not considered noriitally move away from the hook point and the tiiiie required Excludes yarding road changes, computed as TT = Turn Time (minutes) Total Delay Time = Delay Free Turn Time TiOo - 100 Delai%) Regresslon Equation) Total Productive Time + Total Delay Time total turn time (excluding yarding road changes) Averagee.g.: foreignD.F.T. =element 6 minutes, time Delayfor all % =turns 6.2%, In Total percent. Time = rToo - 6) - 1006 6.397 minutes equation)mentalTI (Regression) factors x (1 +occurring percent = 6 minutes, foreignwithin percent aelement turn cycleforeign time). element time - does not include rest breaks, repairs, rerigging, etc. Foreign elements are delays= 14.4%; attributed 6 x (1.144) to machines, = 6.864 minutesmanpower, for material, total turn and time. environ- Total turn time turn time (regression RegressionExcludes landing equation and results yarding in road number changes. of logs yarded per productive hour (no delays, yarding or road changes). Includedhook,Range etc.).of in'P" delays values were for resets,elemental sorting equations. chokers or rigging, and repositioning Total time equation obtained by suming elemental equations of the system (e.g., a turn of logs on the deck for unhooking. outhaul, elen'tnf yardingIncluded cycle in anddelays was werenot treatedresets andas asorting delay. ifchokers IC or rigging. Repositioning a turn of logs on the deck for unhooking was included in the unkcoI FOOTNOTES (continued) th © ScribnerWhere chokers volume arewas preset, approxhnated only the with number Knouf's of rule:choker setters actually participatthg V [(D - 3D5)/lO] (1/2] the hooking operaUon Ic used. where: VI = board feet volume lengthsmall end diameter in thches th feet SourceIogsto keep.over of 40data feet used long to weregenerate scaled these as equaUonstwo logs, one were 40 gross feet long(shift-level) and the time other study 1-4O records feet long. which the thither purchasers were required II. MEDIUM YARDERS: MAXIMUM MAINUNE PUll 25,000 < 71,000 lbs. VARIAEWESREFERENCE MEASURED BUT NOT USED IN REGRESSION EQUATIONS: Dykstra, 19151975 Chordslope %, GroundsiopeGroundslope %, Soil Index,index, Brush Index, Choker Setters, Chasers Gardner,Dykstra, 1980l97 WeightGroundslope of ioad %,in NumberSoilPounds Index, of iogs Brush Per Index,Turn, GrossChasers, Board Chokers Foot Volume Per Turn Gardner, 1980 WeightGross Boardof Ioad Foot in VolumePounds Per Turn,turn Groundslope % Curtis,Gardner, 1978 1980 Gross Board Foot Volume Per Turn,Turn Weight of Ioad in Pounds 4 =forseasonNumber maximumindex, yarding of totalmodification),work,cable "yum" numberinitialroad changes/day, of number "ratio"men working of (total treesaverage on peryarding groundslope acre, operation, number %, oflanding typetrees of size,cut cut, per number index acre, ofcombining chordslope, cable roads the dunny aspectused variableat of a thelanding, workrelating siteground requirementswith profile the 50 Bd. ft/piece, variable corresponding to Forest Service landscape management classes (Orpreservat ion to if of mechantable logs yarded for the day divided by total logs yarded that day) Keller,Curtis, 19791978 GroundslopeCarriageslopeSame as directionheight, regression %, lead groundslope with angle,equation respect actual %,above tonumber lateralouthaul (regression of yardinglogsdirection. hookedff12) distance, within a the turn,slope exception deckdirection height, of chordslope.with perpendicular tspect to outhaul lateral direction. distance of turn from corridor, co II. MEDIUM YIUWERS: MIXIMUM MAINLINE PULL 25000 < 71000 lbs. MICI1INE DITl (1 of 2) YMDER SPECIFICkIIONS REFERENCE SOURCE YARDERMODEL CRRI1GE MODEL MODELTOWER SKYLINE DR(RI PULL/SPEED/C(W(CITY (KIPS/FPM/FT)MAINLINE SLCKPULLING HAULBACK St/Mt/SP/HBiu 5flE 1. Dykstra, 1975 WestFalcon Coast -/-/2000 6/212dl2OO -1-12700 (INCHEs) 4.3. 2.Dykstra, Dykstra, 1975197 1975 SkagitPlanet-LokSnilFalconWest th-Berger Coast GT-W L-1 Sel f-Propel led Marc I -/-/2000 67./l46ii/l2Oo61l2dl200 -/-/2300 412Jl80/4400 .J/22l?22OO -1-127 00 -/ p / ;'/ 5. Gardner, 1980 Skaqit GT-3 1700 67.l46Jl2Oo 1700 2600 .y 'y J;4, 7.6. Gardner9Gardner, 1980 Skagit GT-3 1700 -/-/11Tj 1700 '24'24 2600 4$'4 4'y j' //U 'Pp 9.8. Gardner, 1980 Skagit GT-3 1700 -/-/1 1700 -I-I 2600 ' 1' 'ii, '?' 11. Gardner,0. Gardner, 1980 1980 HC-78BLinklinkHC-7813 BeltBelt -1-11100-/-/1100 -/-/1300-i-il 300 1I4I-I-;J// I-I- II. MEDIUM YARDERS: MAXIMUM MIINIjNE PUll 25,000 < 71,000 lbs. MACHINE DATA (1 of 2) YARDER SPECIFICATIONS REFERENCE SOURCE YARUERMODEI CARRIAGE MOUEI MOUEITOWER SKYLINE DRUM PUU./SPEEU/CAPACITY (KIPs/FPM/rT)MAINIJNE SIACKPUIJJNG UAUIBACK SIJML/SP/IIB LINE(INCII!S) SIZ 12.13. Curtis,CurtIs, 1978 1978 FalconWestSkaglt Coast GT-3 -1-12000 67.f.3'146J12Oo 6l.l46JJ2oO 4l.22722oo -1-12100 -- I//--/ 15.14. Keller, 1979 WestFalcon Coast West(Slackpull Coast(MulKoller Ing) tlspan -1-11600 6'21 2'l2OO -1-11600-/-/1600 -/-/2200 1 Yr//,/Y,. II. MACHINEMEDIUM YARDERS: DATA MAXIMUM MAINlINE PULL 25,000 < 71ç000 lbs (2 0f YARDER SPECIFICATIONS CARRIAGE SPECIFICATIONS TOWER HEIGHT LATERAL CAPABILITY I) OPER. POSITION HOLDING 1. Dykstra,RErERENCES 1975 !NTERIOCK None 49'(FT) WEH1 w LINES CLAMP STOP CAPACITY 4.2.3. Dykstra, 19761975 MechanIcalPlanetary None 41'6"50'49, X- 6.5. Gardner, 1980 Mechanical 44944 9,8.7. Gardner,Gardner,tardner, 1980 1980 Mechanical 4444' xX 12.11.10. CurtIs,Gardner, 1978 1980 None 49'Il41 '6" 13.15.14. Keller,Curtis, 19791978 MechanIcal None 41'6" X X X 200' 5/8" dropllne FOOTNOTES FullBare drum, third gear. Half full drum, lowhigh gear. gear. 6 FullEmpty drum. drum. CarriageNew machine. design required the yarder's mainline be rigged as the skyline and the haulback be used for the skidding line. II. RIGGING&MEDIUM YARDERS: YARDING CONFIGURATION DATA MAXIMUM MAINLINE PULL 25,000 < 71,000 lbs. REFERENCE UPIIIU./ SINGLESPAN/ CUOKERS/ YARDING HAS SWINGING BOOM YES NO LANDING SIZE 1. Dykstra, 1975 IiighleadYARDING SYSTEM USED DOWNhILLUphill Not ApplicableMULT ISPAN ChokersGRAPPLE 'C N/A (LENGTII/WIDTII) 3.2. Dykstra,Dykstra, 1975 1975 GrabinskiNorth Bend UphillUphill Singlespan Chokers 'C 5.4. Gardner,Dykstra, 19761980 RunningRunnIng Skyline UphillUphill Singlespan ChokersChokers 'C 7.6. Gardner, 1980 Running Skyline Downhill Singlespan ChokersChokers 'C 8.9. Gardner, 1980 Running Skyline DownhUphill II SinglespanSinglespan ChokersChokers 'C 11.10. Gardner, 1980 LIve-Gravity Outhaul Uphill Singlespan Chokers 'C 12. Curtis,Gardner, 1978 1980 NorthLIve-Gravity Bend Outhaul UphillUphill Singlespan Chokers 'C 'C 14.13. Keller,Curtis, 19791978 Standing-GravityRunning Skyline Uphill Singlespan Chokers 'C 15. Keller, 1979 RequiredStanding_Haulback®OuthauI Swinging Uphill MultispanSinglespan Chokers 'C FOOTNOTES logsTailbolds swung were from generally corridor outside to landing, the unitKoller boundaries. carriage Il4inlineTailholdsIlaulback takes were holdsup slack. inside carriage the inunit position boundaries. during lateral yarding. with hydraulic clamp used. West Coast mechanical slackpulling carriage used. Guinea line pulls slackS II. CREWMEDIUM DAT/S YARDERS: MAXIMUM MAINLINE PULl 25,000 < 71,000 lbs. REFERENCE SOURCE HOOKTENDER OPERATOR YARDER CREW SIZESLINGERRIGGING 8Y POSITION FOREMAN SIDE SETTERCHOKER CHASER TOTAl EXPERIENCE 1. Dykstra, 1975 Max3Mm 2, Avg 2.8 Max2Mm 1, Avg 1.0 Coninerclal logging Crew 3.2. Dykstra, 1975 MmMax3 2, Avg 2.8 Max2Miii 1, Avg 1.2 Conmiercial logging Crew 4. Dykstra, 19761975 - - Max3MmMax4 2, i,Avg Avg 3,0 2.0 MaxMiiiMaxi 1, Avg 1.0 ConmiercialCoun,uercial logging Crew Crew 6.5. Gardner, 1980 - 1 - 1 1 2 1 5 ConmiercialConinercial logginglogging Crew 8.7. Gardner, 1980 -- 1 -- 1 2 1 5 Comercial logging Crew 10. 9. Gardner, 1980 -- 1 1 - 1 2 1 5 ConmiercialConinercialComercial logging logginglogging Crew 12.11. Curtis,Gardner, 1978 1980 -- 1 - 1 2 - 1 MaxMm 6 5, Avg 6.0 5 CornerclalCornercial logging Crew 14.13. Curtis, 1978 0 1 1 0 0- - 1 MaxMm 8 4, Avg 5.7 3 YardingComercial technique logging was Cre new 15. Keller,Keller, 1979 1979 0 1 1 o 1 1 4 machineryYardingto the crew technique familiar to and crew FOOTNOTE New machine and crew Inexperienced with its operation. II. PIIYSICAIMEDIUM YARDERS: DATA OF SAI[ AREA MAXIMUM MlINL.INE PULl 25,000 7lO0O 'bs. REFERENCE SOURCE SIZE OF UNIT (ACRES)INIll VOt.VED STUDY GENERAL ShAPE OF AREA BROKEN OR NOT) TOPOGRAPHY(SLOPE/ SIZE OFTIMBER (YEARS) AGE SPECIES (MI3F)ACREVOL/ DENSITY STEMS/ ACRE COMMENTS OFIOCAT STUDY JON Uykstra,Dykstra, 1975 0.790.55 RectangularTriangular to UniformGentle and Old-GrowthLargely Aye:150-250 40-85 MaxIlin 0,10 AvgAvg. .9 0 Mt.Forest, FloodHood NationalOregon Dykstra, 1975197 2.69.8 RectangularTriangularIrregular to UniformGentleSteepPrimarily and & broken Old-Growth LargelyOld-Growth Aye:>200150-250 ©®o 65 (net) 40-85 MaxIlinMm 09 20 Avg 1 0, Avg 0 ® Mt.ForestForest,Mt. Flood flood OregonNational National Oregon !i. Gardner, 1980 Uniform,Generally45-60% II II FirLarch- Stand 50_lob® ForestCorant Experinienta- Montana Gardner,Gardner 1980 1980 II H 5O-lO50_lob® CorainForestCorarn Experimental- Montana Gardner, 1980 I,'I H 'I " 5O-lO ForestCorani Experimental- Montana Montana Gardner 1980 0, I, '" 5O-lOt ForestCoram - Montana Experimental H. GardnerGardner, 1980 1980 I, II " SO-lob®50-lO ForestCoram ExperIiiientaExperimental- Montana II. PFIYSICNMEDIUM VIRD[RS: DATA OF SALE AREA MAXIMUM MAINLINE PULL 25,000 < 71,000 lbs SIZE OF UNIT INVOLVED TOPOGRAPHY VOL/ DENSITY 12. CurtIs, 1978REFERENCE SOURCE IN STUDY(ACRES) 22.0 GENERAL OF AREA SWWE rnnBROKEN 0, AvgOR NOT) (SLOPE! Largeiy SIZE TIMBEROF (YEARS) AGE SPECIES (MI3F)ACRE STEMS/ ACRE COMMENTS OF STUDYOC1F ION 13. Curtis, 1978 64 MaxMm 2 0, Avg O.4 Old-GrowthLargely IlInMaxPun 1.00.3, Ivg 0.5, Avg 0.P Mt. Hood NJ. O.7® Oregon Hood N.F. 14. Keller, 1979 20.61 Corridors250'Rectangular 27-53 © 6601(ft3) 195 Max 1.0 Forest,Blodgettlit. Coluitibla Tract 15. Keller, 1979 10.06 250'CorridorsRectangular WIde WIde © 0 27-53 00 6601(ft') 195 County,Forest,Blodgett ColumbiaOregonOreqon Tract FOOTNOTES BrushAverageGround and surfaceground slash surfaceconditionsconditions conditions rangedat the fromhookprovided firm,point firm, evendescribed evenfooting footing.as withfollows: solid and dry soil to rocky, gravel-strewn, or otherwise hazardous footing. 20 =1 heavy,= medium, hampers causes movement some difficulty considerably. in movement.light or nonexistent, does not restrict movement, ByAlso, volume: volume estimates were based on Scribner long-log scale. 60-75% Douglas-fir. Other species: Western Hemlock, Western Red Cedar, Western White Pine, Western Iarch, and Noble fir. ValuesgenerateRange Inare a100's particular of FT3 regressionfor the entire equation study falls area. within this range. an index describing shape of ground profile along the cable road based on the logger's map: 7 regression equations were generated from this area. Density of the area used to 2O =1 convex constantconcave ValuesGeneral are timber a ratio type of was the old-growth total number Douglas-fir of merchantable with mixed logs hemlock, yarded forWestern the dayRed dividedCedar and by associatedthe total numbersubalpine of logsfir species.yarded for the day. IoggingTopography corridors required had northeastIntermediate or southwestsupports. aspects. 00111iTi (Total merchantable conifer) = 13.8" (Douglas-fir) 16.7" HEIGHT (Douglas-fir) = 88.4' H (Western Hemlock) = 12.0" IW1iiT (Western Hemlock) = 79.1' FOOLNOLES (continued) AApproximately net volume to 38% gross Douglas-fir volume ratio and 62%was Western80%. Hemlock by volume, some Red Alder. flyGround volume: surface conditions at the hook point provided firm, approximately 80% Douglas-fir. Other species: even foo.ting.Western Hemlock, Western Red Cedar and Noble Fir. Soil was solid and dry. 11. MEDIUMTIME YARDERSSTUDY DATA 1/3 MAXIMUM MAINLINE PULL 25,000 < 71,000 lbs. thinning[cc., partial, below/TYPE OF CUT SLOPE YARDING LATERAL YARDING CUORDSLOPE GROUNDSL OP F 1. REFERENCE treeabove, length, wholetree, etc] DITES OF STUDY IIINDISTANCE100 (FEET) IIAX525 AVG299.6 MINDISTANCE (FEET) MAX AVG MIN MAX-10 AVG MIN 10 MAX 20 AVG 3.2. Dykstra, 1975 Clearcut JulyJuly26, 23-26, 1973 10-13,9, 18-26, 1113 19, 7550 850400 427.6188.3 -34-10 -9 -38-25 -34.4-19.8-9.9 1510 50 29.727.210.9 6.5.4. Gardner,Dykstra, 1976 1981) PartialShel terwood Cut Sunmier,1973 1974 2l1235 610 273.0--- 0 l0 85 2tL3 -7 -38 -16.0 0 90 18.9 9.8.7. Gardner, 1986D 1986D Group Selection 1 81b isó282------1 d 1iod -3P 2w---2 7---6J 11.10. Gardner, 198 GroupClearcut Selection 6d9ló--- 4 13.12. Curtis,Gardner, 1978 1986D ClearcutC1ercutShe 1 terw.oJ, Aug-SepJun-NovSept-Nov 19751974, 1973 l697---:4: 4 3. -14-10 -50-47 -26.7-26.9 7---7oz_ 15.14. Keller, 1979 LengthThinning,THnning, Log Suniner,Sunwner 1978 4815 10851000 459469 0.01.0 48.044.0 14.215.11p II. MEDIUM YARDERS: MAXIMUM MAINLINE PUll 25,000 < 71,000 lbs. TIME STUDY DATA TYPE or CUT REFERENCE treeabove,[c.c.,thinning length, partial,wholetree, below/ etcj DATES OF STUDY IIINDISTANCE (FEET)SIOPE YARDIN6 HAX AV6 MINDISTANCEIATERAI YIRDIN6 (FEET) tIAX AVG MIN CIIORDSIOPE MAX AVG MIN GROUNDSIOPE MAX AVG Dykstra, 1975 Clearcut 26,July 1973 23-26,10-13, 1113 19, 100 50 400525 188.3299.6 -10 -9 -25-10 -19.8-9.9 10 5020 27.210.9 Dykstra,Gardner, 19761975 ClearcutShelPartial terwood Cut Sunuier,July1973 9, 197418-26, 3575 850610 427.6273.0 0 85 20.3 -34 -7 -38-38 -16.0-34.4 15 0 9050 18.929.7 . Gardner, GroupShelterwood Selection 2482---24ll2! -3P 2J2 Gardner, 1986D l986' ClearcutGroupGroup Selection Selection l8 6J 9lói8ó l6 ôdlod--- l0ólOl0d 42 77w--- Curtis,Gardner, 1978 ClearcutShelClearcut +erw.oJ, Aug-SepJun-NovSept-Nov 19751974, 1973 l976---580--- -14-10 -50-47 -26.7-26.9 6- l.4 Keller,keller, 1979 lengthIengthThinning,Thinning, log log Sun.ne;Suninei 1978 1548 10851000 469459 6l5 2Ofl s6 0.01.0 48.044.0 14.215.1 Q II. MEDIUMTIME STUDYYARDERS: DATA MFXIMUM MAIILINE PULL 25,000 <71,000 lbs. REFERENCE MIN PIECES/TURN MAX AVG PER PIECEMIN (Bd.rt.) GROSS VOLUME MIX AVG PER TURNMINGROSS VOLUME MAX (Ud.Ft-) AVG MIN PER TURN (IRs) WEIGIT MAX AVG INTENSITYTIIIFINING Dykstra, 1975 1 47 2.12.4 15 0 147 564 301.3102.6 15 11252'V&1 586.2 Dykstra, 1975ykstra, 1975 1 5 2.2 0 2084 223.4 J 4l65493.3'1127450 Gardner,Dykstra, 19761980 1 iÔ 6 2.3 0 2820 168.8 O5 252820 329.5 3d1483R R. Gardner, 1980 Pf2) i lf 20 --- 25ó2)20d1O2Od 9256 Gardner, 1980 1978 1. P 807w CurtIs, 1978 1. 11 3.12.1 2.ól.4 keller,I(eller, 1979 1 135.183.8 7J15O3474(0 FOOTNOTES Most time study data in this paper were not presented in a form where ranges and averages could be segregated according to particular theThisaggression paper is a andrangeequations. actual of values averages used and by rangesthe author of values in conjunction observed duringwith this the particularstudy regression The reference does provide a general idea of the range and were not listed by specific regression equations. averages of many parameters listed on this sheet. equation. Seven equations are presented in ValueclearcutEighteen is average acrescondUion. yardingclearcut, distance 46 acres for shelterwood the day recorded cut. in 100's of feet. Author states that shelterwood cut prescriptions were so heavy, they created a near- Valuefollowing is an estimateclasses: of the average ground slope for the area yarded each day, measured perpendicular to the 1 0 to 30%, 2 3Oto 60%; 3>60%. contours and recorded in the NetAverageValue is gross the totalvolume number per log of forlogs running yarded skyline,during the northbend day divided systems.229 by MIIF/log. theand totallongspan number systems of turns (uphill yarded and downhill) for the day. combined .269 MIIF, of TheseFromthe studycruise are generalarea. data: values for the entire study area. 33% of stems removed, 23% of volume removed. Data used to generate this particular production equation came from only a portion Using data from the logging study, volume removed was estimated at 18%. ValuePerpendicular is the number distance of logsto skyline choked corridor.at the beginning of Not the actual lateral yarding distance. a turn. Occasionally "bonus" logs were lost during inhaul. UnmerchántableVolume given in pieces cubic included.feet II. MEDIUMTIME STUDYYARDERS: DATA MAXIMUM MAUIL.INE PUll 25,000 < 71,000 lbs. CUTTING ANGIE10G hAD (°) HEIGHT (FEET) CARRIAG[ HEiGHT (FEET) DECK PRESENTSKIDDER To PRESENTIOADER CHOKERS I OF HUNCHED PRE- CHOKERSPRESET TOT/U. I Y!RDING TOTN 1. Dykstra,REFERENCE 1975 P1TTERN MUI MAX AVG MIN MAX AV MIN MAX AV Cl EAR DECK? YES NO FIOWM YES NOx YES NO x OF TURNS 133 ROADS 5 4.3.2. Dykstra, 19761975 Fun 19 Avg 2 -- x Some x 833427158 2211 8 6.5. Gardner, 1980 No x -- Max 2 x times 10+18 9.8.7. Gardner, 1980 No x x -- 65 10.11.12. Curtis,Gardner, 1978 198019fl0 No x x 26 86+ 13.14. Curtis,Keller, 1978 1979 45° Iead to 6.0 55.0 21.3 1 10 3.1 5 x x 291 91 4 15. Keller, 1979 CorridorCorridorSkyline45° lead tO o 130 494D 8.0 46.0 23.1 4 x x 242 2 FOOTNOTE corridor.Value is the lead angle at which a turn of logs Is yarded. Angle Is measured as a deflectIon angle from the dIrection of the skyline III. PRODUCTIONLARGE YARDERS: DATA MAXIMUM 1AINIANE PUII 2 71,000 lbs. REEERENcES REGRESSION EQUATION-TOTPI TURN TIME (MINUTES) BASEDTIME?DELAY ON REF DELAY % COMMENTS I)ykstra, 1915 4.61769 + 0.00051987 (BFV0Lj+ 0.00146182 (SYDIST) R=.126 to .63w Yes 9.D chokersAnyby inhaulTotalsunuiiing '1ateraU° time wasand outhaul, equationunhookincludedonovertient hook,equations. inobtained of Curtis, l91l 0GS/HR = 23.755 + 2.7716 (0GS) - 0.63694 (AYD) .13 Yes l4.d equations.these four elemental Sherar,Curtis, l971197819?8 3.4961.92410G5/IlR + 0.19270.1014 = 11.138 (SYD)(SYD) + 7.1774 + + 0.3111(IOGSJ+ 0.437 (10G5) (V) - 0.59976 0.35 (V)(AYD) .162.262.29 Yes l2.(i 1J I.injala,Sherar, 1978 191w UIGS/IIR10G5/HR2.284 + 0.4943 = 38.41415.78983 (SYD) +- 0.021183111.3255 + 0.328 (010K) (Y) (SYDIST) - 0.0128329 - 0.172377 (SYDIST) (SoPE1) .3589.2805.402 Yes 23.6 8.&fs.4 03 I.inj&la,I.injala,Linjala, 191l97l91 l91- 10G5/IIR =0GS/HR 35.724624.1710 = + +44.9807 5.543098.34334 - (SETTERS) 0.0329644(010K) (SYDIST) - 0.0567812 + 0.446165 (SYDIST) (510PJ1.) 0.03117 (SYDIST) .3662.4054.2798 Yes 12. 2.6. 03 LinjLla,I.injala, l91 22,5023IOGS/HR + 0GS/HR= 7,51109 54.6604 = (CIlOK) -654010 0.0331174 - -0;0207704 0.0435101 (SYDIST) (SYDISI) (SYDIST) + 0.382246 - 0.0912802 - 4.62756(SIOPEI) (CH0K)''(SIJJPEI) .212 .1827.2618 YesYes 8.5.46.J ©03 See Footnotes on Machine L.inj.la, l91 (SYDIST)10G5/HR 41.9492 - 3.30186 (CREW) + 10.1666 (CIIOK) - 0.025554 .3180 Yes i.4 03 Datathis Table Equation for III. PRODUCTI..ARGE YARDERS: ION DATA MAXIMUM MAINLINE PUU. 71,000 lbs. BASEDDELAY ON FVEE 16. Linj1a,REFERENCE 197cR LOGS/hRREGRESSION(SYIJIST) = 16.9881 EQUATION-TOTAL + 2.28639 TURN (SETTERS) TIME (MINUTES) + 5.65854 (CHOK) - 0.0183524 .2781 R2 TIME.? Yes 8.DELAY % COMMENT S Z1See Footnotes Dataon thisMachine Table equation for 18.17. Linjala,Liujo-la, 197db197 LOGS/MR(SLOPEI)LOGS/HR = 32.225323.1470 -+ 0.567472 7.41064 (SLOPEI)(CHOK) - 0.0211132 (SYDIST) - 0.0816038 .2204.2558 Yes 7. ©(b 20.19. Linjala,Linj&la, l974l97 LOGS/MRLOGS/MR = 69.2603 - 5.26513 (CREW) - 0.0353321 (SYDIST) 84.7407 - 7.6587 (CREW) - 0.0181058 (SYDIST) .1885.2523 YesYes 1.38,1.9O,5.86 5.66© © 1 22.21. Linj4.1a,Linjala, l97 19l!P 0.311246LOGS/MR (SLOPEI) = 51.6547 'Z - 0.04839 (SYIJIST) + 0.598041 (SLOPEI) -42.2686A 12.9092 (CREW) - 0.O32641 (SYDIST) + .2734.2696 Yes O.84,3.7' " I 24.23. Linj.1a.LinJ*la, 197l97 LOGS/MRLOGS/HR5.31694 = (CH0K) 65.101444.4590 - -0.0258301 3,409439.26667 (CREW) (SYDIST) + 5.4371614.2265 (SETTERS)(SETTERS) - .2659 Yes 1.58,3.9' 8.0-' (7) 0 25. Mann, 1979 0.61040+0.0236702 0.00167 + O.O03l7ASYDIST) (VOLUME}W+ (SYDIST) 0.33088 + 0.01958 (RIGGERS) (LATDIST) + 0.33913 (LOGS) .4727.2442 Yes 32.t"'8.N' consideredfree"Reposition" time part(not and ofdelays) delay"Reset" FOOTNOTES TotalExcludes turn yarding time (excludthgroad changes. yarding road changes)- Computed as Tota' Productive Time + Total IJelay Time Dehy Free Turn Time (RegressionTotal Delay Equation) Time OO- eay e.g., D.F.T. = 6 minutes, Delay % = 6.2%, Total time = 100 -6 6.2) 100 - 6.397 minutes ExcludesRegression landing equation and resultsyarding inroad number changes. of logs yarded per productive hour (no delays, yarding or road changes). RangeExcludesinhaul, of "R"unhook). landing va'ues and for yarding eewenta1 road equations. changes, major equipment repairs and general delays when the crew was at the landing and not performing Total time equation obtained by swwning eenenta equations of the system (outhaul, hook, operatingproductiveValues are andrespectivelywork general (e.g., delays crewmean waitingtotal(e.g., delay yardingfor thetime andyarder per road turn to changes, warmand meanup majorin net the productiveequipment morning -timedelays9 usuafly per andturn.abouH5 walUng minutes). for machinery to warm up Total delay time includes operating, non- n the morning). CubicAllnot data foota delay. recorded volume determinedon a turn usingtime ortwo-end yarding conic cycle rule: bss. Time was measured to the nearest minute. C.V. = 0.001818 1((DTime spent in freeing hangups was considered part of the yarding cycle time and + D) + (01)(D2)] where: CV. = log volume in D1Icubic feet = Small= log endlength diameter in feet Insidelarge barkend diameterin inches inside bark in inches FOOTNOTES (continued) fi stoppingskidder wasthe requiredyarding operationto swing logsto permit from thelog landingtruck traffic to another to passarea sincefor loading the yarder to keep the haul setting was on the haul road. road open. Il major source of delay was Scribner volume was approximated with Knouf's Rule: where:[(D - 3DflO] [1/2] = small end diameter in inches logs over 40 feet long were scaled as two logs, one 40 feet long and the other 1-40 feet VI = board foot volumelength in feet long. 4) However,TheSource regression of the data addition coefficientfor these of theequations associated variable were increaseswith gross this (shift-level) R2variable by more was than timenot one foundstudy percent torecords be and significantly whichdoes notthe increasetimber different purchasers the from zeromean at suai.the 0.10 error probability term. level. were required to keep. lit. VARIABLESLARGE YARDERS: MEASURED BUT NOT USED UI REGRESSION EQUATIONS MAXIMUM MAINLINE PULl 71,000 lbs. REFERENCES Curtis,Dykstra, 19781975 ChordslopewithprofileNumber the of index,season cable totalofroad work, numberchanges/day, initial of men number averageworking of groundtreeson yarding perslope acre operation, type of cut, index combining the aspect of the %,work site Groundslope %, Soil Index, Brush Index, Number of Choker Setters, Number of Chasers, Logs per turn. %, landing, number size, of numbertrees cut of percable acre, roads chordslope, used at a duninylanding, variable ground relating Curtis, 1978 yardedSame(U=preservationrequirements asthat Regression da. for to yarding #24nnaximum above. "yum" modification), ? 50 Bd.Ft/piece, "ratio" variable (total correspondingnumber merchantable to Forest logs Service yarded landscapefor the day management divided byclasses total logs Sherar, 1978 NumberGreu,J,l.pe of logs per turn, groundslope %, number of chokers flflown. , ,iu,b.,. d chokers Floun, d0 kir finjJi own. Linjala, 1979 Weather,chokersvolume, soil piecesflown, type, perturn terrainterrainturn. volume, conditions,conditions, pieces per l&iding 1tdingturn. conditions,conditions, loading methodmethod, , slopel,crew size, crew number size, ofnumber choker of setters,chokersetters, nuniber turn of Linjala, 1979 Weather,turnvolume, volume, soilsoil pieces type, type,pieces per terrain terrain turn.per turn. conditions,conditions, l*t.ding lsding conditions,conditions, loading method , slopel, crew size, number of choker setters, crew size, number of chokers flown, turn Linjala, 1979 Weather,chokersturn volume, flown, soilsoil type, type,turnpieces terrainvolume,terrain per turn. conditions,piecesconditions, per turn.l.,.ding 1.ding conditions,conditions, loading method , slopel, crew size, number of choker setters, method , crew size, number of choker setters, number of Linjala,Linjala, 1979 1979 perWeather,turn turn, volume, lOdetIfljsoilsoil type,type,pieces terrainterrain per turn, conditions,conditions, 1ading lding conditions,conditions, i- of ch,okvs Flown. crewloading size, method number , of choker setters, turn crew size, number of choker setters, volume, pieces III. VARIABLESLARGE YARDERS: MEASURED RUT NOT USED IN REGRESSION EQUATIONS MAXIMUM MMNUNE PIJU 71,000 lbs. tInjala,REFERENCES 1979 Weather, soil type, terrain conditions, l*nding conditions loading method slope!, number of choker setters, turn volunie, Unjala, 1979 Weather,pieces soilper turn. type9type, terrain conditions, lisding1."ding conditions loadingloading method method crswg,a,slope!, crew size, turn volume, pieces per turn. number of choker setters, turn volume, Unjala,Unjala, 1979 1979 Weather,flown, soilturn type,volume, terrain pieces conditions,per turn.turn, 14udinglauding conditions lwr1Iu of choker sest .rS. loading method slope!,yarding numberdistance, of chokercrew size, setters, number number of chokers of chokers tinjala,tInjala, 1979 1979 Weather,flown, soilturn type,volume, terrain pieces conditions,per turn. li.ding1*uding conditions loadingloading method method cp,QS,Z.,numberslopel, ofnumber choker of setters,choker setters, number ofnumber of chokers linjala,tInjala, 1979 flown,Weather,chokers turn flown,soil volume, type, turn piecesterrainvolume, per conditions,pieces turn. per turn.lauding conditions loading method number of choker setters, number of chokers Mann,linjala, 1979 1979 Weather,GrosspiecesWeather, boardsoilper soil turn. type,foot type, volumeterrain terrain per conditions, turn,conditions, log laudingturn lauding weight, conditions conditions average board foot volumeloading method perslope!,slope!, log fornumber turn the ofvolume,turn, chokers chordsiope. pieces flown, per turnturn. volume, c3 III. MACHINELJRGE DATAYARDERS: (1 of 2) MAXIMUM MAINLINE PtJLL 71,000 lbs. DRUM PULL/SPEED/CAPACITY (KIPS/FPM/FT) YARDER SPECIFICATIONS LINE SIZE 1. REFERENCE SOURCE YARDERMODEL CARRIAGE MODEL MODELTOWER SKYLINE MAINLINE SLACKPULL1NG IIAUL8ACK SL/ML/SP/IIR (INCHES) 2. CurtIs,Dykstra, 1978 1975 Skaglt 8U-90 Skaglt RCC-l5 115' Spar -- TreeSkaglt 1-90 -/-/4500-1-11450 ,, 819-2Ol/4OOO /4O6/125O -/-/35O I1/1/-/? /I/-/(j 5.3.4. Sherar,Curtis, 1978 Skaglt BIJ.l'f " eu-fl Young IIR-300 " " 1110-lwSkaglt " I, -1-12000 -1-15200 -/11/1/-/. ' / -/, 6.7. LInjala,Sherar, 1978 1979 WashIngton208 " 8U- 8uttrlgsnflutt1g..P T100-HDSkagit 34.&Ph141/165O 23.2O6O/36OO -- -/1 /-/1 10. 9.8. Linjala,Llnjala, 1979 WashIngtonSkagltMadIll M.H.S. " " -/-/13808i175d/113O 7'175O/23OO -iiYi-i 11.12. Linjala,LinJala, 1979 SlacklWashingtonSkaglt157 me " " 762O.g3d/1 .8/1 ;;O/2OOO 500 35.6/278O'634O4.1;'254O/34OO -- -/1-/11/-/--/1I/-/T' 14.13. Llnjala,Llnjala, 1979 1979 RergerYarder II" I" 0/I /-/' III. MACHINEIJRGE YARDERS: DATA (1 o MAXIMUM MAINLINE PUU2) 71,000 lbs. DRUM PUft/SPEED/CAPACITY (KIPS/FPM/FT) YARDER SPECIFICATIONS 15. REFERENCE SOURCE YARDERMODEI CARRIAGE MODEI MODEITOWER I SKYliNE MAINLINE SL.ACKPUU.ING IIAUL.BACK S1/M1/SP/HBPiNE SIZE (INCHES) 16.18.17. Linjala,L.lnjala, 1979 1979 (J0 Butt Rigging 19. L.lnjala,Linjala, 1979 1979 II IV 0 VU 20. Linjala, 1979 VI 23.22.21. L.lnjala,Llnjala, 1979 410 II II 25.24. Mann,Linjala, 1979 1979 MadIll 044 MSPDaneI, B40/9Od;176O l2.l0/lO5BI15OO 7B/9Od/23OO -/1//3'g Ill. MACHINELARGE YARDERS DATA (2 MAXIMUH0f 2)M!INLJNE PULL 71,000 lbs YARDER SPECIFICATIONS LATERAL CAPABILITY CARRIAGE SPECIFICATIONS POSITION HOLDING REFERENCE INTERLOCK TOWER HEIGHT (FT.) WEIGII4 J L LiNESOPER. CLAMP STOP CAPACITY 3.2.1. CurtIs,Dykstra, 1978 1975 None -- 115 Spar90 Tree 6900 -- x x 4.5. Sherar,Curtis, 1978 None 115' Spar Tree 110 470025006900 3OO of 7/8" dropllne 8.7.6. Linjala,Sherar, 19781979 YesNone 90100 10.11. 9. Linjala, 19191979 110100 14.13.12. Linjala9LInjala,LinJala, 19791919 110 17.16.15.18. Llnja1aLinjala,Llnjala,Linjala9 19191979 1919 22.21.20,19. Llnjala,Linjala, 19791919 25.24.23. Mann,Linjala,Llnjala, 1979 1979 None-- 60-- x x FOOTNOTES Half full, low gear. builtYarderHalf full,about was fifth3-drum,1940. gear. trailer mounted, logger-fabricated unit. Drumset model unknown but believed to be a Washington 303 highlead drumset AverageMaximum. maximum. Radio-controlled.Dropline drum capacity = 440' of 7/8" line; speed = 315 F.P.M. (no load); load capacity 44000 pounds. yardingThis equation configuration was generatedgenerated (6 of 8byby models combiningcombining involved). thethe datadata basebase of the seven individual yarder equations of the seven individual yarder equations presentedpresented in inthis this paper. paper when only in an uphill Thishill equationyarding configurationwas generated (5by ofcombining 8 models the involved). data base of the seven individual yarder equations presentedpresented in inthis this paper paper when when only only in in a down- CrabinskiThisa highlead equation yarding was configuration generated by combining the data base yarding configuration (7 of 8 models involved), 8 models involved). of the seven individual yarder equations presented in this paper when only in a 0 whichThree niodels,of eight oryarder how many,models worked involved in areasin this with study a particular worked in degreewindthrow of windthrow.areas ranging from 100% (2 of This equation isto 30%for windthrow.100% windthrow areas. The paper does not indicate FOOTNOTES (continued) 0 Threeindicate of eight which yarder models, models or howinvolved many, inworked this instudy areas worked with ina particularwindthrow areasdegree ranging of windthrow. from 100% to 30% windthrow. This equation is for 80% windthrow areas. The paper does not 0 Threeindicate of eight which yarder models, models or howinvolved many, inworked this instudy areas worked with ina particularwindthrow areasdegree ranging of windthrow. from 100% to 30%' windthrow. This equation is for 30%60% windthrow areas. The paper does not 0 dataThree indicatebases of ofeight whichthe yarder100%, models, 80%,models or 60% howinvolved and many, 30% inworkedwindthrow this instudy areasarea worked equations.with ina particularwindthrow areasdegree ranging of windthrow. from 100% to 30% windthrow. This equation was generated by combining the The paper does not workingThisFull equation drum.non-windthrow was generated and windthrow by combining areas). the total data bases of all eight yarder models in this paper (all yarding configurations, Allhalf yarders full, fourthin this gear. study had towers 90 feet tall or greater. IowUalf gear. full, high gear. lu. URGE YARDERS RIGGING & YARDING CONFIGURATION DATA MI\XIMUM MAINlINE PUll > 71,000 lbs. YM1WR1IAs SWINGIN1IIUJR Curtis,Dykstra,REFERENCE 1978 1975 backStandinglive Skyline-Shotgun(Flyer) used longspan,YARDING SYSTEMno Haul- USED UPIIILI/DOWNHIII UphillUphill SINGlESPAN/MUtTI SingSIngl lespan espan CIIOI(ERS/GRAPPtE Chokers YES NO COMMENTS w CurtIs,Sherar, 1978 1978 liveSkyline-ShotgtinPullsStanding Slack tongspan,longspan, (Flyer) HaulbackHaulbacj g UphillUphillDownhill Singlespan Chokers t.injala,Unjala,Sherar, 1979 19781979 Non-WindthrowHlghleadHlghlead,Illqhlead andNon-Windthrow Grabinski Area APe& RothUphill Not Applicable withSinglespan Grabinski Chokers E.Injala,L.injala,linjala, 1979 19791979 IilghleadIlighlead-Non-WlndthrowHighlead-Non-WindthrowNon- S,fjnJ Area jhrow /r. GrI,sk, - RothUphillDownhill Not Applicable withSinglespan Grabinski ChokersChokers L.Injala,Unjala,L.injala, 19791979 1979 yarderWindthrowFllghleadllighlead-Non-WindthrowIlighlead-Non-Windthrow models) (combined and Grabinski_Non- data1 AreaArea7 RothUphill Not Applicable withSinglespan Grabinski ChokersChokers lln.Jala,tinjala, 1979 1979 Windthrowllighleadlllghlead6 yarder and models)(combinidand Grabinskitlon-. Grabinski data, Non- DownhillUphill Singlespanwith Grabinski ChokersChokers tinjala, 1979 modelltlghleadmodels)Windthrow(combined s) - Non-Wlndthrow (combined1 data,7 yarder 5 yarder Roth Not Applicable with Grabinski Chokers IARGE YARDERS: MAXIMUM MAINUNE PUll 2 71,000 lbs. Ill. RIGGiNG & YARDING CONFIGURATION DATA YARDER I-lAS SWING BOOM 18. REFERENCE YARDING SYSTEM USED UPFIIUJDOWNFIIU SINGIESPIN/MU1T1 ChOKERS/GRAPPLE C he k e rs YES NO 'C COMMENTS 19. Hnjala,L.injala, 1979 1979 Flighlead-l00%models)Grabinski,(combined Non-Windthrow data,2 Windthrow, yarder Both Not Applicable Sinq1espn Clokers K 21.20. L.injala,linjala, 1979 1979 3Illghlead-80% yarderHgh1ead-6OZ models Windthrow, Wlndthrow, BothUphill Not Applicable C hoctrUie kr; x 'C. 23.22. Linjala,L.injala, 1979 IIighlead-A113Ilighlead-30Z yarder models Wlndthrow,Wlndthrow flothI3oth Not Applicable ChocircC Iiok Qr; 24. L.lnjala, 1979 WlndthrowBothIIlghleadAreas,(total Windthrow 3 combined yarder & Areas Grabinskl- andmodels data) Non- Both Siii,lespanGrabinski with ChokQ-S 'C 25. Mann, 1979 RoadNecessarySlackpulllngRunning Open. to Skyline keep Carriage, 1-laul - Mech. SkidderSwing" Uphill Si ngl espan Chokers 'C FOOTHOTES LandingTailbolds size were was generally 0.9 acres. outside the unit boundaries. LengthTaliholds of spanwere (horizontal)outside of unit ranged boundaries. from 350 feet to 1040 feet. co III. CREWLARGE DATA YARDERS: MAXIMUM MAINLINE PULL 71,000 lbs REFERENCE SOURCE IIOOKTENDER OPERATOR YARDER CREW SIZE BY POSITiON RIGGINGSLINGER hOOKER CHOKERSETTER CHASER TOTAL EXPERIENCE 1.2. Curtis,Dykstra, 1978 1975 1 to 49 2.7 1 to 2, V -- Coninercial LoggJng Crew 5.4.3. Sherar,Curtis, 1978 0 0 0 2 2 77to12,T to 11, 5 ConinercialGood familiarity LoggJng withCrew, systems 6.7. Linjala,Sherar, 1978 1979 0 0 0 2 to 4, 2 1 5 to 7, 4 Coninercial oggJng Crew 10. 8.9. Linjala,tinjala, 19791979 1to4,2 4 4to7, 7 13.12.1L [injala,tinjala,Linjala, 19791979 2to4,T2to3,T 4 5to7T 75 16.15.II. Linjala,tinjala, 19791979 2to4,!4lto4,!742 to 3, T1 5to7,U4to7,TI5 to 6, 5 83 17. Linjala, 1979 11to4,2 to 49 44to7,T to 7, 20.19.18. t.injala,tinjala,Unjala, 19791979 2to3,2to3,fl to 4, 1T4 Sto6,!Th4 to5to697 7, T4 III. CREWLARGE DATA YARDERS: MAXIMUM MAINLINE PUIJ 71,000 lbs. YARDER CREW SIZE BY POSITION RIGGING CHOKER 21.22. Unjala,Linjala,REFERENCE 1979 1979 SOURCE HOOKTENDER OPERATOR SLINGER HOOKER 3 to 4, 3.80 SETTER CHASER 6to7,6 to 7, UU TOTAI Coninercial Iogglng Crew EXPERIENCE 25.23.24. Mann,UnJala,L.InJala, 1979 1979 2 toto 4,4, 2.9' 5 to 7, 5.97 settersSomeConvnerclal Inexperienced logglng Crew,choker II II FOOTNOTE Includes rigging slinger. ill. PHYSICALLARGE YARDERS: DATA OF SALE AREA MAXIMUM MAINLINE PULL 71,000 lbs. REFERENCE SOURCE SIZE OF UNIT (ACRES)ININVOLVED STUDY GENERAL SHAPE OF AREA BROI(EN OR NOT) TOPOGRAPHY(SLOPE/ SIZE TIMBEROF (YEARS) AGE SPECIES (MBF)ACREVOI/ DENSITY STEMS/ ACRE COMMENTS OFLOCATION STUDY 2.1. Curtis,Dykstra, 1978 1975 211.0 10.78 RectangularTriangular to MmBrokenRugged and 0 GrowthLargely Old- 150-250 -- j 40-85 -- Mm 0.4 OregonMt. Hood N.E. in 3. Curtis, 1978 30.0 MmAvgMax 0.4-'2 0 LargelyGrowth Old- -- MmAvgMax 0.1. 0.3 4. Sherar, 1978 17.8 Irregular AvgMax 2l.T' GrowthLargely Old- -- 50-70 AvgMax 0.1. Western Oregon 6.5. Sherar, 1978 20.044.0 RectangularRectangulat Leads2 Blind GrowthLargelySecond GrowthOld- 80-100 Douglas-fir 50-70 40 Western Oregon 10. 9.8.7. Linjala, 1979 Southeastern Alaska I, II 11.14.13.12. Linjala,Lmnjala,Llnjala, 1979 II II 17.16.15. Llnjala,Linjala, 1979 I! II 20.19.18. Linjala, 1979 II II'I III. PHYSICILLIRG[ YlRD[RS: D!TA OF SILE AREA MAXIMUM MAN1INE PULL 719000 lbs. REFERENCE SOURCE SIZE OF UNIT (ACRES)ININVOLVED STUDY GENERAL SHAPE OF AREA ROKEI OR NOT)TOPOGRAPHY(5L0P& SIZE OFTIMBER (YEARS) AGE SPECIES ACREYOu(MBF) DENSITY STEMS/ ACRE COMMENTS OF LOCITIONSTUDY Linjala, 1979 Southeastern Maska SI IS Mann,Linjala, 1979 1979 13.3 MixedOld Growth, Conifer -- 0 FresnoSierraSoutheastern N.F Co., Calif. AIagk. FOOTNOTES flrusluGround and surface slash conditionsconditions atat thethe hookhook pointpoint provided firm, were lijht or even footing.nonexistent and did not restrict movement. Soil was solid and dry. Also, volume estiiiiates were based GeneralValueson Scrthner are timber ong-og type was sca'e. old-growth Douglas-fir with mixed hemlock, Uestern an index describing shape of ground profile along the cab'e road based on Red Cedar and associated subalpine fir species. oggti'map: 0 concave; I constant; 2 = convex. DataFanshapedValues used are to settings.a generateratio of the this total equation number were of merchantabletaken from logs yarded for a yarding time study conducted by the U.S. Forest Service in Reigon 10, Alaska. the day divided by the total number of logs yarded for the day differentPUindividual data recordedsale sale areas. areas. on a turn time or yarding cycle basis. In this paper, only the large yarder class (eight yarder models) Data were obtained on twelve differente models of yarders involving a number of was analyzed and no information was given on 22%ModerateSpecies Incense to involved Cedar.steep slopes in partial often cut in removalexcess of were 50%, (by slopes volume): longs continuous 33% Ponderosa/Jeffrey Pine, 20% Sugar Pine, 25% White Fir (A. concolor), or convex. 80%flyAverage volume: Iiouçjlas-fir, vo'ume per20% acre Western removed IIemlock was 25.5 MBF. 60-10% Douglas-fir. Other Species: Western FIemock, Western Red Cedar, Western White Pine, Western Iarch and Nob'e Fir. III. TIMELARGE STUDYYARLWRS: MAXIMUM MAINLINE PULL 71,000 lbs. above,thinning[c.c., wholetree, partial, below/TYPE OF CUT DATES OF DISTANCE (FEET)SLOPE YARDING DISTANCELATERAL YARDING(FEET) CIIORDSLOPE GROUNDS LOP E 1. Dykstra, l95 REFERENCE tree length, etc]Clearcut July 31, Aug 1,3,6, STUDY IIIN 50 MAX1505 AVG703.6 MIN MX AVG -24MIN -60MAX -44.3 AVG MIN 40 80MAX 67.2!VG 2. Curtis, 1978 ClearcutShel terwoo Oct-Nov23,28-30;9,10,13-16,20,21, 1974, 1973 2Jl2fl -1 -36 -14.4 3. Curtis, 1978 She iterwooJ2 Jun-OctOct-NovMay-Nov 1975,1976 3 16 10.9 - -1 -2P 4.5. Sherar, 1978 Clearcut May-NovSun.nevSuniner, 1976 19771977 400200 18501250 1486 789 -6.0 -70 30 100 60 6.7. Llnjala,Sherar, 19781979 CClearcut lea rcu t Fall,CompletedSuniner, 1972 1977 100 50 8501050 539582 -39 40 8060 -14 10. 9.8. Linjala,LinJala, 1979 ClearcutCl ea rcu t ,,'II,I." I. 50 9005001350 536323684 -45-34 21 -9 4046 29.34.6-25.1 11. LinJala, 1979 Clearcut "'I'I,, 100 900 531 -19 25 5.9 12.13.14. Linjala, 1979 Clearcut H,,"I, 100 30 8001350750 437579341 -45-16 2 8040 5 -1.64.8 19 III. LARGETIME YAUDERS: STUDY 1/ M1XIMUM MAINlINE PUll 71,000 lbs. [c,c., partial,TYPE OF CUT REFERENCE above,treethinning wholetree,length, below/ etc] DATES OFSTUDY MINDISTANCE (FEET)SlOPE YARDING MAX AVG 11111DISTINCElATERAL YAUDING(FEET) MAX AVG 11111 CUORDSIOPE MAX AVG MIN GROUNDSIOPE MAX AVG IS. linjala, 1979 Clearcut Fall,Completed 1972 5030 13501300 581576 -45 0 80-1 -17.3 22 linjala,llnjala, 1979 Clearcut 150 5030 95012501350 440697566 -15-34-45 1.0 8018 3.00.8-23.4 Llnjala,linJala, 1979 Clearcut " 3050 5007001050 318395543 ------12-13 9 6.0 6510 21.7-3.4-2.3 Mann,Llnjala, 1979 1979 Clearcut Summer, 1978 4030 9001050 441373 0 18 46.88 -31 45 .354 -15 65 4.8 III. LARGETiME YARI3ERS: STUDY 2,,, MAXIMUM MAINLINE PUll 71,000 lbs. REFERENCE MIN PIECES/TURN MIX IVG PER PIECEMIN (Rd. Ft,) GROSS VOLUME MAX AVG PEfl TURNMINGROSS VOUJME 1IIX (Rd.Ft) AVG INTENSITYTHINNING 2.1. CurtIs,I3ykstra, 1978 1975 1 6. 6 4.i2.1 22 463--- 392.7 5.4.3. Sherar,CurtIs,Sherar, 1978 1978 2.ll.I 1 5. 55 2.82.5 21.410.2 312617 12 8.6.7. LInjala,Unjala,Sherar, 19781979 01 62 2.181.831.71 27.7 0 679457528 86.3-84.4214 10. 9. Linjala,LInjala, 1979 11. 4 2.151.99 23 258203 6&565.8 12,11.13. LinJala.LinJala,Llnjala, 1979 01 475 2.44233L96 --- 12 0 359355 701 8O.1175.388.9 16.15.14. LInjala,LinJala,Llnjala, 1979 0 75 2.052.01L96 0 679701 701 975©86.8 19.18.17. UnJala,LinJala,LInjala, 19791979 0 547 2.01.752.04 0 668384701 lO8.c66.50 21.20. LInjala, 1979 1 46 2.69 85 225313 67.4 23.22. LInjala,Lln.Jala, 19791979 0 6fl 2.162162.09 03 668328 88.192.7'79i 24.25. Mann,UnJala, 1979 1979 1 fl 1.77 35 356 35 3564 25.5 MRF/Acre Removed FOOTNOWS 144 aces shelterwood, 67 acres clearcut. © thistimeTheseAuthor time.fraitie are states dates within that given which shelterwood when the thestudy longspan cut occurred. prescriptionwere yarder was working They DO NOT indicate that data for the particular regression equation so heavy,they created a near-clearcut condition. tither uphill or downhill (2 separate regression equations), They indicate was collected throughout. a followingValue is an averageclasses estimate yarding of the distance average for groundslope the day, recorded for the In 100's of 1 = 0 to 30%; 2 30 to 60%; 3 = > 60%. area yarded each day, measured perpendicular to theA contours negative and sign recorded indicates in downhillthe yarding. feet. NetAverageValue is thegross total volume number per of log logs in thisyarded study during for running the day skyline, divided.229 northbend, by MIff/log. the total and long-span systemsnumber (uphill and of turns downhill) yarded combined for the day.= .269 tlI3F; ChokerUnitsCreek are length. divided in cubic unit feet. at a distance of 1400 feet. Yarding operation essentially ridge to ridge. Both sides of a canyon being yarded. CombinationPerpendicularScribner D.C. of seed scale distance tree used. cut from and the overstory center removalof the skyline cut of thecorridor shelterwood to the method. near end of the log. AverageBasedUniiierchantable on groundslope pieces was Included.not given. nouf's Rule. Average sideslope was 20% III. TIMEI.ARGE STUDY YARDERS: 3/3 MAXIMUM MAINUNE PUll 71,000 lbs CUTTiNG ANGI.ELOG LEAD (i') hEIGHT (FEET) CARRIAGE HEIGHT (FEET) DECK PRESENTT0SKIDDER PRESENTIOADER CHOKERS if OF RUrIdHED PRE- CHOKERSPRE-SET or TOTAI. if YARDING TOTAI 2.1. Dykstra,REFERENCE 1975 PATTERN MIN MAX AVG MIN M!X AVG MIN HX AVG CIEAR DECK? YES NO ftOWN YES xNO YES NO x 201549 TURNS ROADS 21 3. CurtIs,Curtis, 19181978 1 -- 54 4.6.5. Sherar, 1978 -- 2to 3 x 115 9698 2 8.7. Unjala, 1979 --- 21 to 3,! -- 974713 10. 9. Llnjala,linjala, 191919791979 -.-. 1 to 2,12,T 2 -- 100124 12.11.13. l.injala,linjala, 19791979 2 to 3,2.4S -- 2 -- 120 8136 14. l.injala,linjala, 19791979 1 to 3,iT -- 2154 927 15.16. lJnjala,Unjala, 1979 1 to 3,2TT -- 1227 19,18.17. lJnjala,Ijujala, 19791979 1 to 3,TO -- -- 1945 363209 21.20. t.injala.ljnjala, 19791979 2 to1 3,2.4S -- J,T4 -- 174135 22. t.injala,Unjala, 1979 1 to 3,T7 -- 2 -- 45 25.24.23. Mann9Linjala, 1979 1979 Yes to --- -- Sometimes -- 2872 325711 3 129

Appendix B. DEFINITIONS OF VARIABLES USED IN REGRESSION EQUATIONS.

ANGLE The lead angle, in degrees, at which a turn of logs

is lateral inhauled. The angle is measured as a

deflection angle from the skyline corridor to the

inhaul path of the logs. The angle is turned

looking toward the landing.

AYD The average slope yarding distance for the day,

recorded in 100's of feet (i.e., 400 feet = 4).

BFVOL The gross board-feet volume in the turn--includes

unmerchantable pieces. Volumes given in board-feet.

BLOCK A variable used by the author to help isolate

variations which may have occurred between

observations in Block I and Block II of the study

area. Block equals "1" if the observation is

from Block I, and equals "0" if from Block II.

The author states that, for prediction purposes,

"Block" can be set to zero in the equation.

CH Height of the carriage above the ground at the

position of lateral yarding in feet.

CHOK The number of chokers flown.

CHOKERS The number of chokers used in the turn. 1 30

CHORDSLOPE The slope, in percent, of a line segment that

connects the support points of the skyline.

Chordslope inclination is taken from the landing

(i.e., for uphill yarding, chordslopes were

negative). Percent values given as a whole

number (e.g. 30.5%- 30.5).

CREW The number of persons in the yarding crew.

HQII C RE Wl A zero-one dummy variable: when the owner!

operator was a chokersetter, and "1" when he was

not. (NOTE: tn this study the crew with the

more experienced owner/operator as a chokersetter

averaged 54% more volume per hour than the crew

with the less experienced alternate chokersetter).

DKHT Height of the log deck on the landing after the

turn was landed and decked in feet.

DMYSKID A dumy variable to indicate the presence of a

skidder used to keep the landing clear by sorting

and decking logs along the road prior to loading

by a self-loading truck. Skidder Present = 1.

No Skidder Present = 0.

HOOKLOG The number of logs hooked in a turn.

LAN DL OG The number of logs landed in a turn. 131

LANGLE The angle, in degrees, formed by the winch line

and a projected line travelling along the length

Q0 of and through the center of the log (e.g.,a

"LANGLE" implies the log and winch lineare

co-linear, a90° "LANGLE" implies the log is at

right angles to the winch line).

LATDIST The length on the slope measured in feet from the

location of the furthest log in the turn to the

skyline corridor. The distance measured is

perpendicular to the skyline corridor.

LATS D The actual lateral slope distance, in feet, from

the pre-bunching spar to the first log in the

turn (estimated to the nearest five feet).

LDGCREW The number of people in the landingcrew (e.g.,

yarder operator and one chaser would result ina

value of 2 for LDGCREW). The skidder operator is

not considered.

LD 1ST The lateral yarding distance in feet. This is the

actual slope distance the log travels from hook

point to corridor.

LEADTURN The average lead angle, in degrees, ofa turn.

The lead angle is the angle formed between the line

of sight down a log (in the direction of the 1'

landing), and a line parallel to the skyline

corridor. If the line of sight is rotated

toward the corridor in a counter-clockwise

direction, the angle is negative. The

possible range of angles is 900 to 9O°.

LOGS The number of pieces yarded per turn.

RIGGERS The number of chokersetters, including a rigging

slinger if present.

The slope distance down the corridor to the pre-

bunching spar from the yarder measured to the

nearest foot.

SETTERS The number of chokersetters working on the yarding

operation. The rigging slinger is not included.

SIDIST The distance, in feet, a chokersetter had to reach

from the lead of the mainline and haulback to

the position of the farthest log when using the

haulback to pull mainline out from the carriage.

(A 'squirrel11 block was attached to the end of the

haulback and the mainline was pulled through the

"squirrel" block.)

SI NANG The reciprocal of the sine of the lead siie angle (ANGLE). 133

SLO The groundslope at the carriage position in percent.

The percentage is given as a whole number (e.g.

60.5% -p 60.5).

SLOPE The average groundslope in percent. The percentage is given as a whole number (e.g., 60.5%-

60.5). The groundslope inclination is taken

looking toward the landing from the skyline road

(i.e., uphill yarding- "slope" is positive, down-

hill yarding- "slope" is negative).

SLOP El The slope measured from the landing to the hook

point in percent. Percentage given as a whole

number (e.g., 65.5% = 65.5). For uphill yarding,

the value is negative. For downhill yarding, the

value is positive.

SYD The slope yarding distance in 100-foot stations.

SYDIST The slope yarding distance, in feet.

TI The percentage of merchantable stems removed.

Percentage given as a whole number (e.g., 35%=

35.0).

TN VOL The gross board foot volume per turn (Scribner

decimal log rule). Volume given in 10's of

board feet. 134

V The volume of logs per turn measured in cunits.

VOL The gross board-foot volume in the turn. Volume

given in board feet

VOLUME The volume of logs per turn in cubic feet.,

WEIGHT The turn weight in pounds.

ZONE The average lead angle a turn of logs forms with

the skyline. Angles are measured from the skyline

and rotate in a downhill direction toward the

log turn (egg., 00 - turn is parallel to the

skyline). The possible range of angles is00

179°). 135

Appendix C. SYMBOLS AND ABBREVIATIONS.

MBF = Thousand Board Feet

Ac = Acre

KIPS = Thousand Pounds lbs = Pounds

FPM = Feet per Minute

Ft = Foot

SL = Skyline

ML = Mainline

SP = Slackpulling Line

HB = Haulback Line

= Percent

Bd. Ft. = Board Feet

(Ft)3 = Cubic Feet

= Degree

= Coefficient of Multiple Determination

= Average Value of X Variable 136

Appendix D. Formulas for Computing Weighted Averages of Nonlinear Termsin Regression Equations For Two Types of Distributions.

Regreson Formulas for Weighted Averages, by Distribution Type Name ternc Uniform TriangulaiLV

Constant b b (1) b (8)

Linear bx b(x1 x0) (2) 2bx1

Squared bx2 b(x13-x03) ?bx 2 (10) xl - xO

Powe, n n+1 n+1 n+ (-1) bx b(x1 - x0 ) (4) 2b (11) - x0) (n+2)

Inverse

n (-1) b b(lnx1 - lnx0) (5) 2b (12) xl _xO xl

Natural Logarithn blnx bt(x1lnx1 - x1) - (x0lnx0 - x0)] (6) b(lnx1 - 1/2) (13) xl xO

Exponential aebX a(ebxl -ebxO) (7) !_[ebxl(x1_l/b) b(x1 - x0) + 2] (14) x12E

LEGEND: n=power or exponent in natural logarithm e base of natural logarithm (approximately 2.72) maximum value x0 minimum value

a=coefficient of "e' b=coefficients in regression equation

'i)Assumingx0=0 simplifies the formulas.

Corresponds to the widely known 2/3 correction foraverage yarding distance on circular settings

Constant, linear, and squared functionsare special cases of the general formula for power.