DOCSLIB.ORG

Fly-By-Wire Augmented Manual Control - Basic Design Considerations

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Fly-By-Wire Augmented Manual Control - Basic Design Considerations FLY-BY-WIRE AUGMENTED MANUAL CONTROL - BASIC DESIGN CONSIDERATIONS Dominik Niedermeier∗ , Anthony A. Lambregts∗∗ ∗Deutsches Zentrum für Luft- und Raumfahrt e.V., ∗∗Federal Aviation Administration [email protected]; [email protected] Keywords: Fly-by-Wire, Manual augmented control, C∗ control algorithm, C∗U control algorithm Abstract manufacturer allowing reduced training re- quirements After the introduction of Fly-by-Wire (FBW) flight control in the late eighties, several thousands of com- • Weight and maintenance effort reduction by re- mercial FBW aircraft are in service today. Look- placing mechanical components (e.g. pulleys, ing back, it can be concluded that FBW has brought cables) an impressive improvement to handling qualities and • Introduction of flight envelope protection func- flight safety. However, after the long time of experi- tions for enhanced safety ence with the first generations of FBW aircraft, open questions and issues with respect to the design and • Introduction of maneuver/gust load alleviation the operation of FBW have been revealed. The main functions objective of this paper is to discuss those issues and to • Optimization of aerodynamic performance (e.g. point out further research needs in this field. The char- drag reduction by aft-shifted center of gravity) acteristics of manual augmented pitch control algo- rithms implemented in commercial FBW aircraft are Manufacturer Current Models No. of deliveries discussed in detail. Subsequently the paper describes Boeing B777 1003 particular features of Airbus and Boeing FBW control B787 8 systems that are not directly related to the chosen con- Airbus A318/319/320/321 5022 trol algorithm. Open questions and resulting research A330/340 1225 needs with special focus on recent incidents and acci- A380 71 Embraer E-170/190 802 dents are discussed. Antonov An-148 16 Iljushin IL-96 26 1 Introduction Tupolev TU-204/214 74 Suchoi SSJ 100 7 Over 20 years after the introduction of the first digital Total 8106 FBW control system in commercial aircraft by Air- Table 1 Commercial FBW aircraft: No. of Deliveries bus in the late eighties, the trend to replace mechan- ical controls by electrical connections has become ir- Looking back, it can be concluded that FBW de- reversible. Today commercial FBW aircraft from six signs have been very successful and have accumulated different manufacturers, being Airbus, Boeing, Em- a flight safety record as good as, or better than the me- braer, Iljuschin, Tupolev, Suchoi and Antonov, are in chanical flight control systems of the previous aircraft service. The vast majority of them has been delivered generation. Especially with respect to aerodynamic by Boeing, Airbus and Embraer (see Table 1). stall accidents the introduction of FBW control and The main benefits of FBW control leading to its wide the related envelope protection functions have saved application include: a lot of lives. According to [14] there have been 27 stall accidents in transport operations with 848 fatali- • Standardization of control handling qualities ties between 1993-2008. None of those accidents in- between different airplane models of the same volved a FBW aircraft. However, shortly after the 1 DOMINIK NIEDERMEIER, ANTHONY A. LAMBREGTS publication of this statistics two stall accidents with safety" features, e.g. envelope protection. FBW aircraft occurred, but in both cases the envelope This type of control is implemented in Airbus protection function was not working properly due to and Boeing FBW aircraft. sensor malfunctions. Although FBW design has reduced the mechanical To reduce perceived program risks, development system complexity and maintenance effort, the appli- costs and maintain continuity of the product character- cation of FBW control has increased the functional istics, an evolutionary design approach has generally complexity of the Flight Guidance and Control Sys- been used - punctuated by radical exceptions often at tem due to additional control features, necessary mon- the time of first product offering. Airbus chose a FBW itoring functions and reversionary modes to provide design approach that creates an unconventional air- continuity of essential control functions under various craft behavior by providing a pseudo trajectory hold failure conditions. Each reversionary mode tends to feature when the pilot leaves the control loop. The have its own characteristics putting a higher level of resulting loss of classical speed stability led to the in- demand on flight crew proficiency, compared to pre- troduction of envelope protection functions to achieve vious airplane generations, to correctly handle the op- equivalent safety required for certification [7]. In con- erating scenarios for all possible failure conditions. trast, when Boeing introduced FBW control, it was Every aircraft manufacturer has developed its own decided to maintain operational consistency with the distinct design solution. Two general types of FBW previous mechanically controlled airplanes. flight control system design approaches are being The different design concepts introduced by Airbus used today: and Boeing for their first time on the Airbus A320 and the Boeing B777, respectively, were maintained on 1. Simple FBW designs with little or no stability their subsequent FBW aircraft types until today. Gen- augmentation: The traditional mechanical sig- erally aircraft manufacturers tend to keep the design naling from the pilot’s control inceptor to the choices made for their first FBW airplane model in control surfaces is replaced with electrical sig- order to maintain commonality of the handling char- naling, possibly including gain scheduling and acteristics of the subsequent FBW aircraft types. As feedback of sensor output variables that have a result, many FBW design issues continue to be the associated stability derivatives. Classical air- subject of intense debates, including plane dynamic modes and stability character- istics are maintained so that the airplane can • Control inceptor types: column wheel versus be certified under existing airworthiness regu- sidesticks; active versus passive inceptor feel lations. This type of FBW control is implemented in the • Manual augmented control algorithm types and Embraer E-170/190. the resulting aircraft handling characteristics 2. Complex FBW controller designs using non- • Application of envelope protection functions to classical stability/command augmentation: regain equivalent safety to compensate for the Typically, such designs include elements of the loss of classical speed stability and to reduce the type 1 design, as well as other design features, probability of exceeding the envelope bound- possibly including feedbacks of sensor output aries and of Loss of Control (LOC) variables that have no associated stability derivatives (e.g. attitudes or accelerations). No consensus between the different aircraft man- This type of design may also include dynamic ufacturers has emerged on these design issues. Ad- elements (filters) in the feedforward and ditionally, although FBW aircraft are extremely safe, feedback signal paths that result in an "higher incidents and accidents involving FBW aircraft from order controller", which typically alters the different manufacturers have revealed further issues fundamental airplane dynamic modes and related to the design and the operation of FBW con- airplane response to pilot control input. Such trol. Many of the issues result from the specific char- designs may not meet the basic certification acteristics of FBW aircraft and, except of Pilot In- requirement for stability and long term (trim) duced Oscillations (PIO), they do not have a counter- behavior and therefore may need "equivalent part in non FBW airplanes [20]. 2 FBW Augmented Manual Control - Basic Design Considerations This paper describes different manual augmented con- behavior of each algorithm, because its effect on the trol design approaches of commercial aircraft in detail long-term response of key airplane state variables, e.g. and discusses open questions related to the particular such as pitch attitude, airspeed or flight path angle, at design. The main focus will be put on the FBW con- constant thrust with the control inceptor at neutral is trol system design of type 2 which are implemented in at least equally important. This behavior is mainly Boeing and Airbus aircraft. Questions such as influenced by the design of the integral signal path. Depending on the control algorithm the aircraft may • How is the piloting task affected by a particular return to its trimmed airspeed, maintain pitch attitude, manual augmented control algorithm? vertical speed or flight path angle. This behavior significantly affects the pilot’s control • What is the impact of particular features of technique and monitoring task. Consequently, in this existing FBW systems on the pilot-aircraft- paper the distinction between existing control algo- interaction? rithms is made with respect to their long-term re- are discussed with respect to particular design charac- sponses at constant thrust without any pilot control teristics. Furthermore, relevant incidents or accidents input. The objective of this section is to describe the are presented. general characteristics of the control algorithm rather than dealing with the specific design chosen by the 2 Characteristics of Current Control Algorithms corresponding aircraft manufacturer. 2.1 The C∗ Control Algorithm Often the characteristics of a specific control algo- rithm are classified by their
Load more

Recommended publications
  • ALT / VS Selector/Alerter
    ALT / VS Selector / Alerter PN 01279-( ) Pilot’s Operating Handbook ENT ALT SEL ALR DH VS BARO S–TEC * Asterisk indicates pages changed, added, or deleted by List of Effective Pages current revision. Retain this record in front of handbook. Upon receipt of a Record of Revisions revision, insert changes and complete table below. Revision Number Revision Date Insertion Date/Initials 1st Ed. Oct 26, 00 2nd Ed. Jan 15, 08 3rd Ed. Jun 24, 16 3rd Ed. Jun 24, 16 i S–TEC Page Intentionally Blank ii 3rd Ed. Jun 24, 16 S–TEC Table of Contents Sec. Pg. 1 Overview...........................................................................................................1–1 1.1 Document Organization....................................................................1–3 1.2 Purpose..............................................................................................1–3 1.3 General Control Theory....................................................................1–3 1.4 Block Diagram....................................................................................1–4 2 Pre-Flight Procedures...................................................................................2–1 2.1 Pre-Flight Test....................................................................................2–3 3 In-Flight Procedures......................................................................................3–1 3.1 Selector / Alerter Operation..............................................................3–3 3.1.1 Data Entry.............................................................................3–3
    [Show full text]
  • How Doc Draper Became the Father of Inertial Guidance
    (Preprint) AAS 18-121 HOW DOC DRAPER BECAME THE FATHER OF INERTIAL GUIDANCE Philip D. Hattis* With Missouri roots, a Stanford Psychology degree, and a variety of MIT de- grees, Charles Stark “Doc” Draper formulated the basis for reliable and accurate gyro-based sensing technology that enabled the first and many subsequent iner- tial navigation systems. Working with colleagues and students, he created an Instrumentation Laboratory that developed bombsights that changed the balance of World War II in the Pacific. His engineering teams then went on to develop ever smaller and more accurate inertial navigation for aircraft, submarines, stra- tegic missiles, and spaceflight. The resulting inertial navigation systems enable national security, took humans to the Moon, and continue to find new applica- tions. This paper discusses the history of Draper’s path to becoming known as the “Father of Inertial Guidance.” FROM DRAPER’S MISSOURI ROOTS TO MIT ENGINEERING Charles Stark Draper was born in 1901 in Windsor Missouri. His father was a dentist and his mother (nee Stark) was a school teacher. The Stark family developed the Stark apple that was popular in the Midwest and raised the family to prominence1 including a cousin, Lloyd Stark, who became governor of Missouri in 1937. Draper was known to his family and friends as Stark (Figure 1), and later in life was known by colleagues as Doc. During his teenage years, Draper enjoyed tinkering with automobiles. He also worked as an electric linesman (Figure 2), and at age 15 began a liberal arts education at the University of Mis- souri in Rolla.
    [Show full text]
  • Aircraft Flight Manual
    AIRCRAFT FLIGHT MANUAL 770-00048 | REVISION A | 03.23.2016 REVISION HISTORY REVISION DATE DESCRIPTION A March 2016 Initial Release ALTA 8 AIRCRAFT FLIGHT MANUAL PART NUMBER: 770-00048 CONTENTS 2 Revision History 3 Contents 6 ALTA 8 OVERVIEW 7 Disclaimer and Warning 9 Limitation of Liability 11 Introduction 12 Symbols, Abbreviations and Terminology 15 Dimensions 17 Included Items 18 Specifications 22 Limitations 24 System Diagrams 28 ALTA Mobile App 28 Additional Required Components (not included) 29 SETTING UP ALTA 8 30 Unfolding/Folding ALTA 8 33 Radio Installation 38 Radio Mapping 43 Configuring for MōVIs 45 Isolator Cartridges 46 Battery Installation 51 Compass Calibration 54 Propellers 56 First Person View (FPV) 63 Tuning ALTA 8 66 ALTA 8 Flight Parameters 69 Resetting ALTA 8 WiFi Password 70 OPERATING ALTA 8 71 Flight Controller Modes 74 Home Switch | AIRCRAFT FLIGHT MANUAL 3 75 Disarm Safety Switch 76 Status Light 78 Alarms 79 Orientation Lights 80 ALTA App Monitor 81 Data Logging 82 NORMAL PROCEDURES 83 Unpacking and Setup 84 Before Starting 86 Before Takeoff 88 After Every Flight 90 After Last Flight 91 EMERGENCY PROCEDURES 92 Emergency Guidance 93 Status Light Warning Indicator Illuminates 94 Pilot Disorientation 95 Unexpected Flight Controller Behavior 96 Battery Exhaustion 97 Loss of Radio Control Signal 98 Loss of FPV Signal 99 PERFORMANCE 100 Weight / Endurance Performance Data 101 Allowable Gross Weight Gross Weight 102 MAINTAINING ALTA 8 103 General Information and Techniques 104 Maintenance Items 108 Firmware Update Process 109 Motor Alignment 112 Guidelines Following an Accident | AIRCRAFT FLIGHT MANUAL 4 113 TROUBLESHOOTING 116 APPENDIX 117 Appendix A.
    [Show full text]
  • Development and Flight Test Experiences with a Flight-Crucial Digital Control System
    NASA Technical Paper 2857 1 1988 Development and Flight Test Experiences With a Flight-Crucial Digital Control System Dale A. Mackall Ames Research Center Dryden Flight Research Facility Edwards, Calgornia I National Aeronautics I and Space Administration I Scientific and Technical Information Division I CONTENTS Page ~ SUMMARY ................................... 1 I 1 INTRODUCTION . 1 2 NOMENCLATURE . 2 3 SYSTEM SPECIFICATION . 5 3.1 Control Laws and Handling Qualities ................. 5 3.2 Reliability and Fault Tolerance ................... 5 4 DESIGN .................................. 6 4.1 System Architecture and Fault Tolerance ............... 6 4.1.1 Digital flight control system architecture .......... 6 4.1.2 Digital flight control system computer hardware ........ 8 4.1.3 Avionics interface ...................... 8 4.1.4 Pilot interface ........................ 9 4.1.5 Actuator interface ...................... 10 4.1.6 Electrical system interface .................. 11 4.1.7 Selector monitor and failure manager ............. 12 4.1.8 Built-in test and memory mode ................. 14 4.2 ControlLaws ............................. 15 4.2.1 Control law development process ................ 15 4.2.2 Control law design ...................... 15 4.3 Digital Flight Control System Software ................ 17 4.3.1 Software development process ................. 18 4.3.2 Software design ........................ 19 5 SYSTEM-SOFTWARE QUALIFICATION AND DESIGN ITERATIONS ............ 19 5.1 Schedule ............................... 20 5.2 Software Verification ........................ 21 5.2.1 Verification test plan .................... 21 5.2.2 Verification support equipment . ................ 22 5.2.3 Verification tests ...................... 22 5.2.4 Reverifying the design iterations ............... 24 5.3 System Validation .......................... 24 5.3.1 Validation test plan . ............... 24 5.3.2 Support equipment ....................... 25 5.3.3 Validation tests ....................... 25 5.3.4 Revalidation of designs ...................
    [Show full text]
  • Air Force Airframe and Powerplant (A&P) Certification Program
    Air Force Airframe and Powerplant (A&P) Certification Program Introduction: Most military aircraft maintenance technicians are eligible to pursue the Federal Aviation Administration (FAA) Airframe & Powerplant (A&P) certification based on documented evidence of 30 months practical aircraft maintenance experience in airframe and powerplant systems per Title 14, Code of Federal Regulations (CFR), Part 65- Certification: Airmen Other Than Flight Crew Members; Subpart D-Mechanics. Air Force education, training and experience and FAA eligibility requirements per Title 14, CFR Part 65.77. This FAA-approved program is a voluntary program which benefits the technician and the Air Force, with consideration to professional development, recruitment, retention, and transition. Completing this program, outlined in the program Qualification Training Package (QTP), will assist technicians in meeting FAA eligibility requirements and being better-prepared for the FAA exams. Three-Tier Program: The program is a three-tier training and experience program. These elements are required for program completion and are important for individual development, knowledge assessment, meeting FAA certification eligibility, and preparation for the FAA exams: Three Online Courses (02AF1-General, 02AF2-Airframe, & 02AF3-Powerplant). On the Job Training (OJT) Qualification Training Package(QTP). Documented evidence of 30 months practical experience in airframe and powerplant systems. Program Eligibility: Active duty, guard and reserve technicians who possess at least a 5-skill level in one of the following aircraft maintenance AFSCs are eligible to enroll: 2A0X1, 2A090, 2A2X1, 2A2X2, 2A2X3, 2A3X3, 2A3X4, 2A3X5, 2A3X7, 2A3X8, 2A390, 2A300, 2A5X1, 2A5X2, 2A5X3, 2A5X4, 2A590, 2A500, 2A6X1, 2A6X3, 2A6X4, 2A6X5, 2A6X6, 2A690, 2A691, 2A600 (except AGE), 2A7X1, 2A7X2, 2A7X3, 2A7X5, 2A790, 2A8X1, 2A8X2, 2A9X1, 2A9X2, and 2A9X3.
    [Show full text]
  • CANARD.WING LIFT INTERFERENCE RELATED to MANEUVERING AIRCRAFT at SUBSONIC SPEEDS by Blair B
    https://ntrs.nasa.gov/search.jsp?R=19740003706 2020-03-23T12:22:11+00:00Z NASA TECHNICAL NASA TM X-2897 MEMORANDUM CO CN| I X CANARD.WING LIFT INTERFERENCE RELATED TO MANEUVERING AIRCRAFT AT SUBSONIC SPEEDS by Blair B. Gloss and Linwood W. McKmney Langley Research Center Hampton, Va. 23665 NATIONAL AERONAUTICS AND SPACE ADMINISTRATION • WASHINGTON, D. C. • DECEMBER 1973 1.. Report No. 2. Government Accession No. 3. Recipient's Catalog No. NASA TM X-2897 4. Title and Subtitle 5. Report Date CANARD-WING LIFT INTERFERENCE RELATED TO December 1973 MANEUVERING AIRCRAFT AT SUBSONIC SPEEDS 6. Performing Organization Code 7. Author(s) 8. Performing Organization Report No. L-9096 Blair B. Gloss and Linwood W. McKinney 10. Work Unit No. 9. Performing Organization Name and Address • 760-67-01-01 NASA Langley Research Center 11. Contract or Grant No. Hampton, Va. 23665 13. Type of Report and Period Covered 12. Sponsoring Agency Name and Address Technical Memorandum National Aeronautics and Space Administration 14. Sponsoring Agency Code Washington , D . C . 20546 15. Supplementary Notes 16. Abstract An investigation was conducted at Mach numbers of 0.7 and 0.9 to determine the lift interference effect of canard location on wing planforms typical of maneuvering fighter con- figurations. The canard had an exposed area of 16.0 percent of the wing reference area and was located in the plane of the wing or in a position 18.5 percent of the wing mean geometric chord above the wing plane. In addition, the canard could be located at two longitudinal stations.
    [Show full text]
  • Faa Ac 20-186
    U.S. Department Advisory of Transportation Federal Aviation Administration Circular Subject: Airworthiness and Operational Date: 7/22/16 AC No: 20-186 Approval of Cockpit Voice Recorder Initiated by: AFS-300 Change: Systems 1 GENERAL INFORMATION. 1.1 Purpose. This advisory circular (AC) provides guidance for compliance with applicable regulations for the airworthiness and operational approval for required cockpit voice recorder (CVR) systems. Non-required installations may use this guidance when installing a CVR system as a voluntary safety enhancement. This AC is not mandatory and is not a regulation. This AC describes an acceptable means, but not the only means, to comply with Title 14 of the Code of Federal Regulations (14 CFR). However, if you use the means described in this AC, you must conform to it in totality for required installations. 1.2 Audience. We, the Federal Aviation Administration (FAA), wrote this AC for you, the aircraft manufacturers, CVR system manufacturers, aircraft operators, Maintenance Repair and Overhaul (MRO) Organizations and Supplemental Type Certificate (STC) applicants. 1.3 Cancellation. This AC cancels AC 25.1457-1A, Cockpit Voice Recorder Installations, dated November 3, 1969. 1.4 Related 14 CFR Parts. Sections of 14 CFR parts 23, 25, 27, 29, 91, 121, 125, 129, and 135 detail design substantiation and operational approval requirements directly applicable to the CVR system. See Appendix A, Flowcharts, to determine the applicable regulations for your aircraft and type of operation. Listed below are the specific 14 CFR sections applicable to this AC: • Part 23, § 23.1457, Cockpit Voice Recorders. • Part 23, § 23.1529, Instructions for Continued Airworthiness.
    [Show full text]
  • Installation Manual, Document Number 200-800-0002 Or Later Approved Revision, Is Followed
    9800 Martel Road Lenoir City, TN 37772 PPAAVV8800 High-fidelity Audio-Video In-Flight Entertainment System With DVD/MP3/CD Player and Radio Receiver STC-PMA Document P/N 200-800-0101 Revision 6 September 2005 Installation and Operation Manual Warranty is not valid unless this product is installed by an Authorized PS Engineering dealer or if a PS Engineering harness is purchased. PS Engineering, Inc. 2005 © Copyright Notice Any reproduction or retransmittal of this publication, or any portion thereof, without the expressed written permission of PS Engi- neering, Inc. is strictly prohibited. For further information contact the Publications Manager at PS Engineering, Inc., 9800 Martel Road, Lenoir City, TN 37772. Phone (865) 988-9800. Table of Contents SECTION I GENERAL INFORMATION........................................................................ 1-1 1.1 INTRODUCTION........................................................................................................... 1-1 1.2 SCOPE ............................................................................................................................. 1-1 1.3 EQUIPMENT DESCRIPTION ..................................................................................... 1-1 1.4 APPROVAL BASIS (PENDING) ..................................................................................... 1-1 1.5 SPECIFICATIONS......................................................................................................... 1-2 1.6 EQUIPMENT SUPPLIED ............................................................................................
    [Show full text]
  • Fly-By-Wire - Wikipedia, the Free Encyclopedia 11-8-20 下午5:33 Fly-By-Wire from Wikipedia, the Free Encyclopedia
    Fly-by-wire - Wikipedia, the free encyclopedia 11-8-20 下午5:33 Fly-by-wire From Wikipedia, the free encyclopedia Fly-by-wire (FBW) is a system that replaces the Fly-by-wire conventional manual flight controls of an aircraft with an electronic interface. The movements of flight controls are converted to electronic signals transmitted by wires (hence the fly-by-wire term), and flight control computers determine how to move the actuators at each control surface to provide the ordered response. The fly-by-wire system also allows automatic signals sent by the aircraft's computers to perform functions without the pilot's input, as in systems that automatically help stabilize the aircraft.[1] Contents Green colored flight control wiring of a test aircraft 1 Development 1.1 Basic operation 1.1.1 Command 1.1.2 Automatic Stability Systems 1.2 Safety and redundancy 1.3 Weight saving 1.4 History 2 Analog systems 3 Digital systems 3.1 Applications 3.2 Legislation 3.3 Redundancy 3.4 Airbus/Boeing 4 Engine digital control 5 Further developments 5.1 Fly-by-optics 5.2 Power-by-wire 5.3 Fly-by-wireless 5.4 Intelligent Flight Control System 6 See also 7 References 8 External links Development http://en.wikipedia.org/wiki/Fly-by-wire Page 1 of 9 Fly-by-wire - Wikipedia, the free encyclopedia 11-8-20 下午5:33 Mechanical and hydro-mechanical flight control systems are relatively heavy and require careful routing of flight control cables through the aircraft by systems of pulleys, cranks, tension cables and hydraulic pipes.
    [Show full text]
  • Vertical Motion Simulator Experiment on Stall Recovery Guidance
    NASA/TP{2017{219733 Vertical Motion Simulator Experiment on Stall Recovery Guidance Stefan Schuet National Aeronautics and Space Administration Thomas Lombaerts Stinger Ghaffarian Technologies, Inc. Vahram Stepanyan Universities Space Research Association John Kaneshige, Kimberlee Shish, Peter Robinson National Aeronautics and Space Administration Gordon Hardy Retired Research Test Pilot Science Applications International Corporation October 2017 NASA STI Program. in Profile Since its founding, NASA has been dedicated • CONFERENCE PUBLICATION. to the advancement of aeronautics and space Collected papers from scientific and science. The NASA scientific and technical technical conferences, symposia, seminars, information (STI) program plays a key part or other meetings sponsored or in helping NASA maintain this important co-sponsored by NASA. role. • SPECIAL PUBLICATION. Scientific, The NASA STI Program operates under the technical, or historical information from auspices of the Agency Chief Information NASA programs, projects, and missions, Officer. It collects, organizes, provides for often concerned with subjects having archiving, and disseminates NASA's STI. substantial public interest. The NASA STI Program provides access to the NASA Aeronautics and Space Database • TECHNICAL TRANSLATION. English- and its public interface, the NASA Technical language translations of foreign scientific Report Server, thus providing one of the and technical material pertinent to largest collection of aeronautical and space NASA's mission. science STI in the world. Results are Specialized services also include organizing published in both non-NASA channels and and publishing research results, distributing by NASA in the NASA STI Report Series, specialized research announcements and which includes the following report types: feeds, providing information desk and • TECHNICAL PUBLICATION. Reports of personal search support, and enabling data completed research or a major significant exchange services.
    [Show full text]
  • Glider Handbook, Chapter 2: Components and Systems
    Chapter 2 Components and Systems Introduction Although gliders come in an array of shapes and sizes, the basic design features of most gliders are fundamentally the same. All gliders conform to the aerodynamic principles that make flight possible. When air flows over the wings of a glider, the wings produce a force called lift that allows the aircraft to stay aloft. Glider wings are designed to produce maximum lift with minimum drag. 2-1 Glider Design With each generation of new materials and development and improvements in aerodynamics, the performance of gliders The earlier gliders were made mainly of wood with metal has increased. One measure of performance is glide ratio. A fastenings, stays, and control cables. Subsequent designs glide ratio of 30:1 means that in smooth air a glider can travel led to a fuselage made of fabric-covered steel tubing forward 30 feet while only losing 1 foot of altitude. Glide glued to wood and fabric wings for lightness and strength. ratio is discussed further in Chapter 5, Glider Performance. New materials, such as carbon fiber, fiberglass, glass reinforced plastic (GRP), and Kevlar® are now being used Due to the critical role that aerodynamic efficiency plays in to developed stronger and lighter gliders. Modern gliders the performance of a glider, gliders often have aerodynamic are usually designed by computer-aided software to increase features seldom found in other aircraft. The wings of a modern performance. The first glider to use fiberglass extensively racing glider have a specially designed low-drag laminar flow was the Akaflieg Stuttgart FS-24 Phönix, which first flew airfoil.
    [Show full text]
  • Using an Autothrottle to Compare Techniques for Saving Fuel on A
    Iowa State University Capstones, Theses and Graduate Theses and Dissertations Dissertations 2010 Using an autothrottle ot compare techniques for saving fuel on a regional jet aircraft Rebecca Marie Johnson Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/etd Part of the Electrical and Computer Engineering Commons Recommended Citation Johnson, Rebecca Marie, "Using an autothrottle ot compare techniques for saving fuel on a regional jet aircraft" (2010). Graduate Theses and Dissertations. 11358. https://lib.dr.iastate.edu/etd/11358 This Thesis is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Graduate Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. Using an autothrottle to compare techniques for saving fuel on A regional jet aircraft by Rebecca Marie Johnson A thesis submitted to the graduate faculty in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE Major: Electrical Engineering Program of Study Committee: Umesh Vaidya, Major Professor Qingze Zou Baskar Ganapathayasubramanian Iowa State University Ames, Iowa 2010 Copyright c Rebecca Marie Johnson, 2010. All rights reserved. ii DEDICATION I gratefully acknowledge everyone who contributed to the successful completion of this research. Bill Piche, my supervisor at Rockwell Collins, was supportive from day one, as were many of my colleagues. I also appreciate the efforts of my thesis committee, Drs. Umesh Vaidya, Qingze Zou, and Baskar Ganapathayasubramanian. I would also like to thank Dr.
    [Show full text]