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Soaring Weather
Chapter 16 SOARING WEATHER While horse racing may be the "Sport of Kings," of the craft depends on the weather and the skill soaring may be considered the "King of Sports." of the pilot. Forward thrust comes from gliding Soaring bears the relationship to flying that sailing downward relative to the air the same as thrust bears to power boating. Soaring has made notable is developed in a power-off glide by a conven contributions to meteorology. For example, soar tional aircraft. Therefore, to gain or maintain ing pilots have probed thunderstorms and moun altitude, the soaring pilot must rely on upward tain waves with findings that have made flying motion of the air. safer for all pilots. However, soaring is primarily To a sailplane pilot, "lift" means the rate of recreational. climb he can achieve in an up-current, while "sink" A sailplane must have auxiliary power to be denotes his rate of descent in a downdraft or in come airborne such as a winch, a ground tow, or neutral air. "Zero sink" means that upward cur a tow by a powered aircraft. Once the sailcraft is rents are just strong enough to enable him to hold airborne and the tow cable released, performance altitude but not to climb. Sailplanes are highly 171 r efficient machines; a sink rate of a mere 2 feet per second. There is no point in trying to soar until second provides an airspeed of about 40 knots, and weather conditions favor vertical speeds greater a sink rate of 6 feet per second gives an airspeed than the minimum sink rate of the aircraft. -
Hang Glider: Range Maximization the Problem Is to Compute the flight Inputs to a Hang Glider So As to Provide a Maximum Range flight
Hang Glider: Range Maximization The problem is to compute the flight inputs to a hang glider so as to provide a maximum range flight. This problem first appears in [1]. The hang glider has weight W (glider plus pilot), a lift force L acting perpendicular to its velocity vr relative to the air, and a drag force D acting in a direction opposite to vr. Denote by x the horizontal position of the glider, by vx the horizontal component of the absolute velocity, by y the vertical position, and by vy the vertical component of absolute velocity. The airmass is not static: there is a thermal just 250 meters ahead. The profile of the thermal is given by the following upward wind velocity: 2 2 − x −2.5 x u (x) = u e ( R ) 1 − − 2.5 . a m R We take R = 100 m and um = 2.5 m/s. Note, MKS units are used through- out. The upwind profile is shown in Figure 1. Letting η denote the angle between vr and the horizontal plane, we have the following equations of motion: 1 x˙ = vx, v˙x = m (−L sin η − D cos η), 1 y˙ = vy, v˙y = m (L cos η − D sin η − W ) with q vy − ua(x) 2 2 η = arctan , vr = vx + (vy − ua(x)) , vx 1 1 L = c ρSv2,D = c (c )ρSv2,W = mg. 2 L r 2 D L r The glider is controlled by the lift coefficient cL. The drag coefficient is assumed to depend on the lift coefficient as 2 cD(cL) = c0 + kcL where c0 = 0.034 and k = 0.069662. -
Soaring Magazine Index for 1990 to 1999/1990To1999 Organized by Subject
Soaring Magazine Index for 1990 to 1999/1990to1999 organized by subject The contents have all been re-entered by hand, so thereare going to be typos and confusion between author and subject, etc... Please send along any corrections and suggestions for improvement. 1-26 Bob Dittert, 1-26s + Rain = Championship,December,1999, page 24 1-26 Association Bob Hurni, 1991 1-26 Championships (Caesar Creek),January,1992, pages 18-24 George Powell, The Stealth Glider,January,1992, pages 28-30 MikeGrogan, Hallelujah! I Am Flying Again,January,1992, pages 35-39 Harry Senn, Why 1-26’sDon’tFly Sports Class,February,1992, pages 39-41 Luan & John Walker, 1992 1-26 Championships (Midlothian, TX),January,1993, pages 40-44 Joe Walter, What a Contest (the 1-26 Championships),October,1993, page 3 Jim Hard, (1993) 1-26 Championships at Albert Lea, Minnesota,November,1993, pages 19-25 TomHolloran, GPS: The First Year-Almost,November,1993, pages 26, 28-30 1000 Kilometer Flights Robert Penn, Sixteen Contestants Fly 1000 KilometersinPossible World RecordContest Task,No- vember,1990, page 15 YanWhytlaw, The 1000 KM Club,March, 1992, pages 20-23 KenKochanski, The Joy of Soaring (1000KM from Blairstown by Bob Templin and Ken Kochanski)!, September,1992, page 6 Sterling V.Starr, 1000KM in the Sky! (Over the Sierraand White Mountains),March, 1993, pages 42-45 Advertising Mark Kennedy, Soaring in Action: Please Note! (No) July Classified Ads,June, 1997, page 14 Convenience and Savings (with Soaring Classifieds),October,1997, page 4 Aerobatics Wade Nelson, An Aerobatic Ride at Estrella,January,1990, page 3 Trish Durbin, Cat Among the Pigeons,February,1990, page 20 Bob Kupps, The ThirdWorld Glider Aerobatic Championships (Hockenheim),March, 1990, page 15 Trish Durbin, Author’sResponse (to "Cat Among the Pigeons" Complaints),July,1990, page 2 Thomas J. -
Soaring Magazine Index for 1989/1989 Organized by Subject
Soaring Magazine Index for 1989/1989 organized by subject The contents have all been re-entered by hand, so there are going to be typos and confusion between author and subject, etc... Please send along any corrections and suggestions for improvement. Aerobatics Robert Welliever, Of White Hats and Pretty Girls, February, page 21 Bob O'Dell, Sailplane Aerobatics Nationals (1988 at Edna, TX), a Big Success, February, page 26 Gail Davis, Glider Aerobatics Needs Attained, June, page 10 Gail Davis, Aerobatic Team Needs Help (Going to Worlds in Germany), July, page 10 George McManus, Archeological Research (at Estrella, AZ), October, page 36 Aerodynamics Peter Masak, Sailplane (In¯ight) Bug Wiper System, February, page 40 Flight Tests Richard H. Johnson, Sailplane Performance Flight Test Methods, May, page 26 Richard H. Johnson, A Flight Test Evaluation of the DG-600, August, page 12 Af®liates, Chapters, and Clubs Vernon Meyer, Don't Forget the Little Guys! (Hinckley Soaring), January, page 4 Steve Hudson, Growth (of Fault Line Flyers) Discussed, February, page 2 New Soaring Club (Post Mills) Formed in Vermont, February, page 6 Dale Fletcher, Information Requested on Local Awards, February, page 9 Terry Hurley, Airlines - One to Six, March, page 12 Bill McClure, Thanks! Soaring Magazine, June, page 6 D. Taylor, Indy '90, June, page 9 Post Mills Soaring Club Off and Running, July, page 10 Phyliss Wells, Club Gains 86 New Members, September, page 8 New Association Formed (Franconia Soaring), October, page 7 1-26 Association Paul Sampson, Sorry, Charlie Dobkins (1-26 Nationals Author), January, page 2 Lew Neyland, Credit Where Credit is Due (Old Goat Winner is Pat DeNaples), February, page 2 1-26 Association on the Move (with New 1989 Executive Board), April, page 8 A.C. -
2.1 ANOTHER LOOK at the SIERRA WAVE PROJECT: 50 YEARS LATER Vanda Grubišic and John Lewis Desert Research Institute, Reno, Neva
2.1 ANOTHER LOOK AT THE SIERRA WAVE PROJECT: 50 YEARS LATER Vanda Grubiˇsi´c∗ and John Lewis Desert Research Institute, Reno, Nevada 1. INTRODUCTION aerodynamically-minded Germans found a way to contribute to this field—via the development ofthe In early 20th century, the sport ofmanned bal- glider or sailplane. In the pre-WWI period, glid- loon racing merged with meteorology to explore ers were biplanes whose two wings were held to- the circulation around mid-latitude weather systems gether by struts. But in the early 1920s, Wolfgang (Meisinger 1924; Lewis 1995). The information Klemperer designed and built a cantilever mono- gained was meager, but the consequences grave— plane glider that removed the outside rigging and the death oftwo aeronauts, LeRoy Meisinger and used “...the Junkers principle ofa wing with inter- James Neeley. Their balloon was struck by light- nal bracing” (von Karm´an 1967, p. 98). Theodore ening in a nighttime thunderstorm over central Illi- von Karm´an gives a vivid and lively account of nois in 1924 (Lewis and Moore 1995). After this the technical accomplishments ofthese aerodynam- event, the U.S. Weather Bureau halted studies that icists, many ofthem university students, during the involved manned balloons. The justification for the 1920s and 1930s (von Karm´an 1967). use ofthe freeballoon was its natural tendency Since gliders are non-powered craft, a consider- to move as an air parcel and thereby afford a La- able skill and familiarity with local air currents is grangian view ofthe phenomenon. Just afterthe required to fly them. In his reminiscences, Heinz turn ofmid-20th century, another meteorological ex- Lettau also makes mention ofthe influence that periment, equally dangerous, was accomplished in experiences with these motorless craft, in his case the lee ofthe Sierra Nevada. -
TOTAL ENERGY COMPENSATION in PRACTICE by Rudolph Brozel ILEC Gmbh Bayreuth, Germany, September 1985 Edited by Thomas Knauff, & Dave Nadler April, 2002
TOTAL ENERGY COMPENSATION IN PRACTICE by Rudolph Brozel ILEC GmbH Bayreuth, Germany, September 1985 Edited by Thomas Knauff, & Dave Nadler April, 2002 This article is copyright protected © ILEC GmbH, all rights reserved. Reproduction with the approval of ILEC GmbH only. FORWARD Rudolf Brozel and Juergen Schindler founded ILEC in 1981. Rudolf Brozel was the original designer of ILEC variometer systems and total energy probes. Sadly, Rudolph Brozel passed away in 1998. ILEC instruments and probes are the result of extensive testing over many years. More than 6,000 pilots around the world now use ILEC total energy probes. ILEC variometers are the variometer of choice of many pilots, for both competition and club use. Current ILEC variometers include the SC7 basic variometer, the SB9 backup variometer, and the SN10 flight computer. INTRODUCTION The following article is a summary of conclusions drawn from theoretical work over several years, including wind tunnel experiments and in-flight measurements. This research helps to explain the differences between the real response of a total energy variometer and what a soaring pilot would prefer, or the ideal behaviour. This article will help glider pilots better understand the response of the variometer, and also aid in improving an existing system. You will understand the semi-technical information better after you read the following article the second or third time. THE INFLUENCE OF ACCELERATION ON THE SINK RATE OF A SAILPLANE AND ON THE INDICATION OF THE VARIOMETER. Astute pilots may have noticed when they perform a normal pull-up manoeuvre, as they might to enter a thermal; the TE (total energy) variometer first indicates a down reading, whereas the non-compensated variometer would rapidly go to the positive stop. -
Free Flight Vol Libre
Feb/Mar 1/95 free flight • vol libre Soaring Association ofCanada 1945–1995 a VSA Blanik soars past a cloud–framed Hope Mountain. Dave Woodcock AC TURNS FIFTY! For most individuals it is a time to reflect on what we will spend doing during the last third of our lives. Organizations are somewhat different in that their initia- S tors wanted them to grow long after them. A fiftieth anniversary gives us an opportunity to reflect on what was accomplished and tip our hat at those who did the pioneering work. Then after, we need to set our course for the next quarter of a century. SAC’s fiftieth comes at a time when the framework in which we operated to this day is going to change beyond our wildest expectations. Some of this will be good, some will be a challenge. Let’s review some key factors: • We baby boomers are pushing the demographic bulge near the 50 age zone. This is the period of life where we should have more leisure time, and hopefully disposable income for ... SOARING. That’s good. • The economy is not what we have been used to in Canada since 1945. Cost of flying is in- creasing for everyone, more so for power pilots. That’s an opportunity. • Transport Canada will possibly be a very different organization focused on commercial opera- tors. For the recreational aviation community, this is both a challenge and an opportunity to strive for a less regulated and bureaucratic environment. Growth and deregulation should therefore be the course we set for ourselves for the next quarter of a century. -
Soaring Forecasts: Digging for Data at NWS Web Sites by Dan Shoemaker, NWS Fort Worth, TX
December 2003 National Weather Service Volume 2, Number 3 Soaring Forecasts: Digging For Data at NWS Web Sites by Dan Shoemaker, NWS Fort Worth, TX The National Weather Service (NWS) sphere alone work to keep their refuge from In this Issue: serves a broad base of aviation users that the everyday world aloft. include soaring pilots. The main sources The soaring community is extensive. Soaring Forecasts: of information are TAFs, from Weather One estimate puts the number around Digging For Data Forecast Offices “WFOs”, numerous 20,000 pilots flying sailplanes, hang gliders, products from the Aviation Weather Cen- and paragliders. As a group, these pilots have at NWS Web Sites ter “AWC” and the computer generated had to hone good meteorological sense to Surface Analysis 1 guidance from the National Centers for maximize their soaring experience. It’s worth Environmental Prediction “NCEP”. noting that sailplanes have soared past the Specific NWS Forecast for soaring are tropopause, and hang gliders and paragliders Volcanic Ash: mainly throughout the southwestern por- have reached altitudes above 18,000 ft. Hang Significant Aviation tion of the US. But but we’ll discuss gliders and paragliders routinely make Hazard 5 weather products and information that unpowered cross country trips of more than assist making soaring forecast for other 100 miles. The current hang glider cross locations, as savvy, resourceful soaring pi- country record is over 400 miles. All by tap- lots, hangliders, and paragliders enjoy im- ping the resources of the free air without a mensely the thrill of letting the atmo- powered assist after release. -
Dynamic Soaring: Aerodynamics for Albatrosses
IOP PUBLISHING EUROPEAN JOURNAL OF PHYSICS Eur. J. Phys. 30 (2009) 75–84 doi:10.1088/0143-0807/30/1/008 Dynamic soaring: aerodynamics for albatrosses Mark Denny 5114 Sandgate Road, RR#1, Victoria, British Columbia, V9C 3Z2, Canada E-mail: [email protected] Received 27 August 2008, in final form 1 October 2008 Published 6 November 2008 Online at stacks.iop.org/EJP/30/75 Abstract Albatrosses have evolved to soar and glide efficiently. By maximizing their lift- to-drag ratio L/D, albatrosses can gain energy from the wind and can travel long distances with little effort. We simplify the difficult aerodynamic equations of motion by assuming that albatrosses maintain a constant L/D. Analytic solutions to the simplified equations provide an instructive and appealing example of fixed-wing aerodynamics suitable for undergraduate demonstration. 1. Introduction Albatrosses (figure 1) are among the most pelagic of birds. They nest on remote islands in the ‘Roaring Forties’ and ‘Furious Fifties’, i.e., in the wind-swept southern regions of the Pacific, Atlantic and Indian Oceans that surround Antarctica. They feed primarily upon squid, and roam widely for food to feed their young. A typical albatross feeding trip may take 10 days and cover 1000 km per day. Albatrosses may make half a dozen circumpolar trips each year, taking advantage of the prevailing westerly winds, and adopting characteristic looping flight patterns that best extract energy from the wind. When travelling northward they loop in an anticlockwise direction, and loop clockwise when heading south (we will explain why this is so). Albatrosses are supremely well adapted to this pelagic1 life in the windy southern oceans. -
½ Skydrop User Guide
½ SkyDrop user guide 2102 SkyDrop – combined GPS variometer instant analog/digital vario – no delay response GPS tracklog – IGC, FAI1 Civil approved or KML Bluetooth & USB connectivity – Android, iOS, PC full customizable – multiple screens, layouts and widgets xc navigation functions – optimized route for competitions thermal assistant, airspace warning, wind speed & direction ground speed, altitude above ground, compass, odometer light weight & compact size – 68g, 98 x 58 x 20 mm about this user guide Despite the fact that we made SkyDrop vario as intuitive as possible, we recommend to read this user guide. We know well this is not your favorite activity, so just briefly go through to understand basic concept. You can leave detailed study of every function for winter time or if you want to learn about specific function. You don’t have to keep the printed copy, PDF copy is stored inside vario (SD card), or you can find it on our webpage skybean.eu or vps.skybean.eu buttons long press (for 1s) – turn on, pull up menu bar, move to upper level in menu, toggle widget value, start/stop flight stopwatch, short press – confirm, list adjustable widgets on home screen, turn off device (if menu bar is pulled up), press & hold for 5s to turn device off short press – scroll between home screens to the left, select widget menu if menu bar is pulled up, scroll up in menu, lower value during setting parameter, press & hold to rapid value lowering short press – scroll between home screens to the right, select settings menu if menu bar is pulled up, scroll down in menu, raise value during setting parameter, press & hold to rapid value raising important note – please read SkyDrop is in silent mode after start-up, so if you want to hear vario sound, select FTime widget and manually start the flight by long press. -
Easter 2011 Easter 2011
The Prayer Book Society of Canada NewsletterThe Prayer Book Society of Canada Newsletter Easter 2011 Easter 2011 In Memoriam: The Revd. Dr. Robert Crouse I NSIDE By the Rt. Revd. Anthony Burton medieval worlds that now has the last tracker organ in Nova 2 The Revd. Dr. Robert Crouse, an international following. Scotia, installed it in his tiny PBSC Annual one of the most influential rural church and started a General Meeting Canadian theologians of his Many of his students baroque concert series that has generation, died Jan. 15 in discovered in themselves attracted musicians to summer 3 his rural childhood home on a vocation to holy orders. concerts for 47 years. About The PBSC – 25 Crouse Road, Crousetown, His sermons continue to be the same time he started a Years On Nova Scotia, where his family a touchstone for preachers university choir that continues had lived for more than 200 around the world. For all to flourish. 7 years. He was 80. that, it was neither his Bible Translation academic career nor his Later he would help found in Eastern He had left the house tireless voluntary service to an annual theological Malaysia 70 years before to attend the Church that set him apart conference, an academic King’s Collegiate School journal, and a publishing in Windsor, Nova Scotia, house, all of which survive where he would later be him. He gave popular judged the most brilliant talks on theology as it was student in its 263- embodied in the church year history. Academic architecture of Europe, distinction followed, which he loved to explore, with degrees from King’s, camera in hand. -
1. Check out Your Bird
1. Check out your bird ➢ Where are the feet placed on the body? Measure L Range of values: 47% Hawaiian Petrel (Procellariidae) to Common Murre 74% (Alcidae) 1. Check out your bird ➢ Where are the feet placed on the body? Measure L Range of values: 42% Chicken (Phasianidae) to Western Greebe 100% (Podicipedidae) 1. Check out your bird ➢ What are the feet like ? Write a brief description and make a drawing ➢ What is the tarsus like ? Write a brief description of the cross-section shape (Note: use calipers to measure tarsus cross-section) Tarsus Ratio = Parallel to leg movement Perpendicular to leg movement Round (Wood 1993) Elliptical Tarsus Tarsus 1. Check out your bird Tarsus Ratio = Parallel to leg movement Perpendicular to leg movement Range of values: Values < 1.00 1.00 Black-winged Petrel 0.80 RFBO (Procellariidae) (Sulidae) to to BRBO Common Murre (Sulidae) 1.50 (Alcidae) 0.80 Tarso-metatarsus Section Ratio (Wood 1993) Major and minor axes (a and b) of one tarsus per bird measured with vernier calipers at mid- point between ankle and knee. Cross-section ratio (a / b) reflects the extent to which tarsus is laterally compressed. Leg Position vs Tarsus Ratio 80 COMU 70 BRBO 60 Leg Position SOTEBOPE 50 RFBOBWPE GWGU (% Body Length)(% Body HAPE 40 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 Tarsus Ratio 2. Make Bird Measurements ➢ Weight (to the closest gram): ➢ Lay out bird on its back and stretch the wings out. 2. Make Wing Measurements Wing Span = Wing Chord = Wing Aspect Ratio = Wing Loading = 2.