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High-Lift Systems on Commercial Subsonic Airliners https://ntrs.nasa.gov/search.jsp?R=19960052267 2020-06-16T03:18:47+00:00Z , j / ,_ / t - ¸ /I i NASA Contractor Report 4746 High-Lift Systems on Commercial Subsonic Airliners Peter K. C. Rudolph CONTRACT A46374D(LAS) September 1996 National Aeronautics and Space Administration NASAContractorReport4746 High-Lift Systems on Commercial Subsonic Airliners Peter K. C. Rudolph PKCR, Inc. 13683 18th Ave. SW Seattle, WA 98166 Prepared for Ames Research Center CONTRACT A46374D(LAS) September 1996 National Aeronautics and Space Administration Ames Research Center Moffett Field, California 94035-1000 Table of Contents Page Introduction ................................................................................................................................ 3 Chapter 1 Types of High-Lift Systems: Their Geometry, Functions, and Design Criteria ...... 3 1.1 Types of High-Lift Systems ............................................................................. 3 1.1.1 Leading-Edge Devices ........................................................................ 1.1.2 Trailing-Edge Devices ........................................................................ 10 19 1.2 Support and Actuation Concepts ..................................................................... 1.2.1 Leading-Edge Devices ........................................................................ 22 1.2.2 Trailing-Edge Devices ........................................................................ 26 1.3 Geometric Parameters of High-Lift Devices ................................................... 36 1.4 Design Requirements and Criteria for High-Lift Systems ............................... 37 1.4.1 Failure Modes and Fail-Safe Design .................................................... 37 1.4.2 Protrusions and Flow Blockage ........................................................... 39 39 1.4.3 Spanwise High-Lift Continuity ............................................................ 1.5 Characteristics and Constraints of High-Lift Devices ..................................... 40 1.6 Interactions between Leading- and Trailing-Edge Devices ............................. 43 45 Chapter 2 Review of High-Lift Systems on Current Commercial Airliners ............................. 45 2.1 Boeing Airplanes .............................................................................................. 2.1.1 Boeing 707-320 .................................................................................... 45 2.1.2 Boeing 727 ........................................................................................... 45 5O 2.1.3 Boeing 737 ........................................................................................... 2.1.4 Boeing 747 ........................................................................................... 51 2.1.5 Boeing 757 ........................................................................................... 54 56 2.1.6 Boeing 767 ........................................................................................... 59 2.1.7 Boeing 777 ........................................................................................... 2.2 McDonnell Douglas Airplanes ......................................................................... 61 2.2.1 MD-80/87 ............................................................................................. 61 2.2.2 DC-10/MD-11 ...................................................................................... 63 2.2.3 YC-15 and C-17 Trailing-Edge Flaps .................................................. 65 2.3 Lockheed L1011 .............................................................................................. 65 67 2.4 Airbus Airplanes .............................................................................................. 2.4.1 Airbus A300 ......................................................................................... 67 2.4.2 Airbus A310-300 .................................................................................. 68 2.4.3 Airbus A320 ......................................................................................... 68 2.4.4 Airbus A321 ......................................................................................... 72 2.4.5 Airbus A330/340 .................................................................................. 74 75 2.5 British Aerospace BAe146 and RJ70/80/100 .................................................. 77 2.6 Ilyushin 96 ........................................................................................................ 77 2.7 Performance Comparison ................................................................................. 80 2.8 High-Lift System Impact on Noise .................................................................. °,° 111 2.9 Lessons Learned from Review ......................................................................... 81 2.9.1 Leading-Edge Devices ......................................................................... 81 2.9.2 Trailing-Edge Devices ......................................................................... 82 2.9.3 Boeing Summary .................................................................................. 84 2.9.4 McDonnell Douglas Summary ............................................................. 85 2.9.5 Lockheed Summary ............................................................................. 85 2.9.6 Airbus Summary .................................................................................. 86 2.9.7 British Aerospace Summary ................................................................ 86 Chapter 3 Conceptual Studies for Improved High-Lift Systems ............................................... 87 3.1 Summary of Studies ......................................................................................... 87 3.2 Leading-Edge Devices ..................................................................................... 89 3.2.1 Krueger Flaps ....................................................................................... 89 3.2.2 Tapered Slats and Conical Slat Motion ................................................ 91 3.2.3 Shallow Slat ......................................................................................... 93 3.3 Trailing-Edge Devices ..................................................................................... 95 3.3.1 Flap Shapes .......................................................................................... 95 3.3.2 Spanwise Continuity ............................................................................ 98 3.3.3 Flap Airloads and Their Reaction into the Flap Mechanisms .............. 99 3.4 Trailing-Edge Flap Mechanisms ...................................................................... 100 3.4.1 Summary of Flap Mechanisms ............................................................ 100 3.4.2 Design for Aerodynamic Efficiency .................................................... 101 3.4.3 Design for Reliability and Good Wear Characteristics ........................ 102 3.4.4 Design for Low Cost ............................................................................ 103 3.4.5 Mechanism Selection ........................................................................... 104 3.4.6 Simple, Four-Bar Linkages .................................................................. 104 3.4.7 The Link/Track Mechanism--Trailing-Edge Flap Mechanism of the Future? ....................................................................................... 106 3.4.8 Link/Track Mechanism versus Simple, Four-Bar Linkage .................. 113 Chapter 4 Economics of High-Lift Systems .............................................................................. 117 4.1 Tendencies in High-Lift-System Development ............................................... 117 4.2 Weight Estimating for High-Lift Devices ........................................................ 118 4.2.1 Weights of Trailing-Edge Flaps ........................................................... 118 4.2.2 Weights of Leading-Edge Devices ...................................................... 120 4.2.3 Weight Scaling for Airplane Size ........................................................ 122 4.2.4 Impact of Weight Reduction on the Airplane ...................................... 122 4.3 Importance of Takeoff L/D and Maximum Lift Coefficient ............................ 122 4.4 Cost Model for Manufacturing Cost ................................................................ 123 4.5 Relating Cost Model to Real Airplane ............................................................. 124 4.6 Part Count ........................................................................................................ 125 4.6.1 Trailing-Edge Flaps .............................................................................. 125 4.6.2 Leading-Edge Devices ......................................................................... 130 4.6.3 Part-Count Scaling for Airplane Size ................................................... 131 iv 4.7 Calculating High-Lift-System Cost for an Airplane of 250,000 lb Gross Weight .................................................................................................... 131 4.7.1 Determination of the Constants ............................................................ 131 4.7.2 Weight, Part Count, and Manufacturing Cost of High-Lift Systems ...............................................................................................
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