Power Effects on Stability and Control !• Gee Bee R1 Racer: an engine with wings and almost no tail" • During W.W.II, the size of fighters remained about the same, but installed horse
Trang 1• Greek mythology: Daedalus and Icarus!
– Attempt to escape from Crete !
• 863 BC: Bladud ( King Lear s father)!
– 9th king of England !
– First tower-jumper!
– Wings of feathers!
– Died of a broken neck !
Aviation History:
Mythology to 1990
Robert Stengel, Aircraft Flight Dynamics, MAE 331, 2012 "
Copyright 2012 by Robert Stengel All rights reserved For educational use only.!
http://www.princeton.edu/~stengel/MAE331.html ! http://www.princeton.edu/~stengel/FlightDynamics.html !
Antiquity
Experimentalists"
• Henri Pitot: Pitot tube (1732)!
• Benjamin Robins: Whirling
arm "wind tunnel (1742)!
• Sketches "modern" airplane configuration (1799)!
• Hand-launched glider (1804)!
• Papers on applied aerodynamics (1809-1810)!
• Triplane glider carrying 10-yr-old boy (1849)!
• Monoplane glider carrying coachman (1853)!
– Cayley's coachman had a steering oar with cruciform blades!
• Modern reconstruction (right)!
Sir George Cayley!
Visionaries and Theorists!
• 1831: Thomas Walker !
– Various glider concepts!
– Tandem-wing design influenced Langley!
• 1843: William Henson & John Stringfellow !
– Aerial steam carriage concept!
– Vision of commercial air transportation (with Marriott and Columbine, The Aerial Transit Company)!
• 1860-1900: Theoretical aerodynamic contributions!
– Kirchhoff!
Trang 219 th Century Flyers"
• 1868: Jean Marie Le Bris!
– Artificial Albatross glides a short distance!
• 1891-96: Hang-glider flights!
– Otto Lilienthal !
– Chanute, Pilcher, !
• 1890: Clement Ader !
– Steam-powered Eole hops!
• 1894: Sir Hiram Maxim !
– Steam-powered biplane hops!
– Vertical gyro/servo control of the elevator!
• 1884: Alexander Mozhaisky 's
steam-powered manned airplane!
– brief hop off the ground!
– flat-plate wings!
• 1874: Felix du Temple 's hot-air engine
manned monoplane!
flies 3/4 mile!
• Wilbur and Orville were bicycle mechanics from Dayton, OH!
• Self-taught, empirical approach to flight!
• Wind-tunnel, kite, and glider experiments!
flight ends in success!
Trang 3Wright Brothers
• Recognized importance of
– Bank to turn preferable to
skid turn !
– Roll control induced yaw!
– Too much stability!
• hinders control!
• increases response to gusts!
– Wings can stall !
• Experimental gliders !
– Wing warp controlled roll!
– Foreplanes controlled pitch!
• 2nd glider !
– Vertical tail !
– Coupled to the wing warp to
suppress adverse yaw !
• 1906: 2nd successful aviator: Alberto Santos-Dumont , standing!!
– High dihedral, forward control surface !
• Wrights secretive about results until 1908; few further technical contributions !
• 1908: Glenn Curtiss et al incorporate ailerons!
– Wright brothers sue for infringement
of 1906 US patent (and win)! • 1909: Louis Bleriot's flight
across the English Channel !
Glenn Curtiss"
• 1908: Glenn Curtiss becomes dominant US aviation inventor!
• 1914: Langley s Aerodrome finally flies!
– Curtiss et al modify and fly Langley Aerodrome!
– Unsuccessful effort to discredit Wright patent!
– Alexander Graham Bell s support!
• Prior to 1903, it was thought that an airplane should hold its course alone!
– Pilot could steer by deflecting the rudder !
• This suggested: !
– Aft-mounted tail!
– Wing dihedral or high wing!
– Proper center-of-mass location !
Trang 4Early Aircraft Control"
• Lillienthal shifted center of mass in
hang gliders!
cruciform tail!
and movable rudder and elevator
surfaces!
surfaces!
Pilot Inputs to Control:
the Wright Approach"
• 1903 Wright Flyer !
– Prone pilot !
– Stick for pitch control!
– Hip cradle for wing-warping roll control!
– Aileron-rudder interconnect (ARI)!
– http://www.airspacemag.com/how-things-work/1903-flyer.html !
• 1905 Wright Flyer !
– Upright pilot !
– Left lever for pitch!
– Right lever for roll and yaw with ARI!
– Right lever later modified to separate
roll (left-right) and yaw (fore-aft) control) w/o ARI!
– Feet not used for control!
– http://wright.nasa.gov/airplane/
air1905.html !
Control Linkages:
the Bleriot Approach"
• Louis Bleriot introduced:!
– Rudder bar controlled by feet!
– Center stick for pitch and roll control !
Bleriot XI!
Aviation in The Great War"
• 1914-18: World War I changes the complexion of flying!
– Reconnaissance!
– Air superiority (dog fights) !
– Bombing!
– Personal transport !
• Wrights US monopoly broken by licensing for war effort!
• Aircraft Design !
– Biplanes, a few mono- and triplanes!
– Design for practical functions!
– Multiple engines, larger aircraft!
– Aft tails!
– Increased maneuverability, speed, g-loads, altitude!
– Improved piston engines!
– Tractor propellers !
SPAD S.VII!
World War I fighter replicas in flight!
http://www.youtube.com/watch?v=JsT_rgScrg0 !
Trang 5Maneuvering World War I Aircraft"
• Maneuverable aircraft with
idiosyncrasies!
– Rotary engine!
– Small tail surfaces!
– Reliability issues !
• Maneuvering to stalls and spins !
• S nap roll : rudder and elevator!
• Barrel roll : aileron !
• Cross-control (e.g., right rudder, left
stick)!
– glide path control during landing !
– good view of landing point !
• Unintended snap rolls led to spins and
accidents during takeoff or landing !
http://www.youtube.com/watch?v=OBH_Mb0Kj2s!
http://www.youtube.com/watch?v=6ETc1mNNQg8!
Sopwith Camel"
• Rotary engine induced gyroscopic coupling!
• Highly maneuverable!
• Aft fuel tank; when full, center of mass was too far aft for stability !
• Vertical tail too small, spin recovery not automatic with centering of controls!
http://www.youtube.com/watch?v=3ApowyEXSXM !
S.E.-5 vs Fokker D.VII"
• RAF S.E.-5 : theoretical approach to design !
– Best WWI design from the Royal Aircraft
Factory !
– Stationary engine!
– High dihedral!
– Stable spiral mode!
– High control forces!
– Poor maneuverability!
– Relatively safe and effective!
• Fokker D.VII : empirical approach to
design!
– Horn balances to reduce control forces!
– Stationary engine!
– Neutral-to-negative stability!
– Good maneuverability!
– Relatively dangerous!
The Correct Answer:
Handling) Qualities !
– Stability and controllability characteristics as perceived
by the pilot !
• Desired attributes: Stability of the S.E.-5 and
controllability of the D.VII!
http://www.youtube.com/watch?v=kwXcwu6JQk8 !
Trang 6Between the Wars
Aviation Between the Wars"
• 1918-38: !
– Birth of airlines!
– Trophy races
http://www.youtube.com/watch?
v=R3AROX6OO88 !
– Aviation firsts (Lindbergh crosses the Atlantic, 1927)
http://www.youtube.com/watch?
v=uIUL_qUJUOo&feature=related !
– Flying boats ! – Sport aviation!
Curtiss R3C-2! Gee-Bee R-1!
Ryan NYP!
http://www.youtube.com/watch?v=DwqYh995YhU !
Air Commerce Act of 1926"
• Airlines formed to carry mail and passengers: !
– Northwest (1926) !
– Eastern (1927), bankruptcy!
– Pan Am (1927), bankruptcy!
– Boeing Air Transport (1927), became United (1931) !
– Delta (1928) , consolidated with Northwest, 2010 !
– American (1930) !
– TWA (1930), acquired by American!
– Continental (1934), consolidated with United, 2010!
Boeing 40!
Ford Tri-Motor! Lockheed Vega !
http://www.youtube.com/watch?v=3a8G87qnZz4 !
Commercial Aircraft of the 1930s !
• Streamlining, engine cowlings!
• Douglas DC-1, DC-2, DC-3!
• Lockheed 14 Super Electra, Boeing 247 , exterior and interior!
Trang 7Seaplanes Became the First
TransOceanic Air Transports !
• PanAm led the way !
– 1 st scheduled TransPacific flights(1935)!
– 1 st scheduled TransAtlantic flights(1938)!
– 1 st scheduled non-stop Trans-Atlantic flights (VS-44, 1939)!
• Boeing B-314, Vought-Sikorsky VS-44, Shorts Solent !
• Superseded by more efficient landplanes (lighter, less drag)!
http://www.youtube.com/watch?v=x8SkeE1h_-A!
1930s Air Racers Presage Fighters of World War II"
• Aircraft Design ! – Transition to monoplanes!
– Metal skins and structure!
– Semi-monocoque design!
– Improved aerodynamics!
– Improved in-line, V, and radial engines !
– Increased maneuverability, speed, altitude!
– Seaplanes faster than landplanes (why?) !
Supermarine S.6B!
Hughes H-1 (replica)! Macchi MC72!
V = 566 km/hr!
V = 709 km/hr!
V = 547 km/hr!
World War II
http://www.youtube.com/watch?v=hgyFzUVtDOY&feature=related!
Technology of World War II Aviation"
• 1938-45: Analytical and experimental approach to design!
– Many configurations designed and flight-tested !
– Increased specialization; radar, navigation, and communication!
– Approaching the "sonic barrier !
• Aircraft Design ! !
– Large, powerful, high-flying aircraft!
– Turbocharged engines!
– Oxygen and Pressurization!
Spitfire!
P-51D!
B-17!
http://www.youtube.com/watch?v=stKz-elSYy0!
Trang 8Power Effects on Stability and Control !
• Gee Bee R1 Racer: an engine with
wings and almost no tail"
• During W.W.II, the size of fighters
remained about the same, but
installed horsepower doubled (F4F
vs F8F)!
• Use of flaps means high power at
low speed, increasing relative
significance of thrust effects"
• Short-Takeoff-and-Landing (STOL)
aircraft augment takeoff/landing lift in
many ways, e.g.,"
– Full-span flaps"
– Deflected thrust"
Grumman F8F!
Grumman F4F!
GB R1!
World War II Carrier-Based Airplanes!
• Takeoff without catapult , relatively low landing speed
http://www.youtube.com/watch?
v=4dySbhK1vNk !
• Tailhook and arresting gear!
• Carrier steams into wind!
folding wings) affects stability and
control!
Chance-Vought F4U Corsair!
Grumman TBF!
F4U flight"
http://www.youtube.com/watch?v=JANR0XPtVzw!
SBD Dauntless Flight"
http://www.youtube.com/watch?v=aiJhcKgg4eE&feature=related!
F4U!
Carrier Crash Landings!
http://www.youtube.com/watch?v=H8Bim7-hZfg!
Grumman TBF !
Multi-Engine Aircraft of World War II!
• Large W.W.II aircraft had
unpowered controls:!
arising from balancing to
• Severe engine-out problem
Douglas A-26!
North American B-25!
Martin B-26!
WW II Military Flying Boats!
• Seaplanes proved useful during World War II !
Lockheed PBY Catalina!
Martin PBM Mariner ! Martin PB2M Mars!
Boeing XPBB Sea Ranger!
Saunders-Roe SR.36 Lerwick!
Grumman JRF-1 Goose!
Trang 9Birth of the Jet Airplane"
Bell P-59A (1942)!
Gloster Meteor (1943)!
Messerschitt Me 262 (1942)!
Heinkel He 178 (1939)!
Gloster E/28/39 (1941)! Early Jet Aircraft
From Propellers to Jets!
Douglas XB-43!
Douglas XB-42 Mixmaster!
• Performance of the first jet aircraft
outstripped stability and control
technology!
– Lacked satisfactory actuators, sensors, and control electronics!
– Transistor: 1947, integrated circuit:
1958 !
• Dramatic dynamic variations over larger flight envelope!
– Control mechanisms designed to lighten pilot loads were subject to instability!
reliability, increased cost, and higher weight !
North American B-45!
Lockheed P-80!
Douglas F3D!
Convair XF-81!
Trang 10From Straight to Swept Wings !
• Straight-wing models were redesigned with swept wings to
reduce compressibility effects on drag!
• Dramatic change in stability, control, and flying qualities!
• North American FJ-1
and FJ-4 Fury! • Republic F-84B Thunderbird and F-84F Thunderstreak! • Grumman F9F-2 Panther and F9F-6 Cougar!
Toward Supersonic Flight and Stealth
Fighter Jets of the 1950s !
• Emphasis on supersonic speed!
Republic F-105!
Lockheed F-104!
Convair F-102!
McDonnell F-101!
North American F-100!
Fighter Jets of the 1960s !
• Emphasis on mission!
Dassault Mirage F1!
Convair F-106! Grumman A-6!
Trang 11Fighter Jets of the 1980s !
• Emphasis on performance!
Repbulic F-105!
Lockheed-Martin F-117!
Panavia Tornado!
BAE/McDonnell-Douglas AV-8B!
Mig-31A!
Personal and Business Aircraft
Early Concepts for Safe
Personal Aircraft !
• Low takeoff and landing speeds!
• Benign flying qualities!
• Stall/spin-proof designs!
• Ercoupe !
– Limited control authority!
– Control wheel, ARI, no rudder pedals!
– Limited center-of-mass travel!
– Limited speed range!
– Wing leveling and lateral stability!
Curtiss Tanager!
Piper J-3 Cub!
Ercoupe!
• Mignet Flying Flea (Homebuilt, pivoting main wing, no ailerons, unrecoverable dive)!
• V-tail Beechcraft Bonanza Model 35 (10,000 built, 250 in-flight structural failures ) !
• American Yankee AA-1 (BD-1, hot , stalls and spins) !
• Bede BD-5 (Home-built, unforgiving flying qualities)!
Trang 12Propeller-Driven Personal Aircraft !
• Single reciprocating engine, mechanical controls, fixed or
retracting gear, high price!
• Cirrus SR-20/22 has a recovery parachute (used 13 times
through 2008, saved 24 lives; 2 parachute failures)!
Piper Malibu!
Cessna 172!
Cirrus SR20/22!
Beech Bonanza A36!
Mooney M20!
• Twin turbojet/fan engines!
Gulfstream II!
Cessna Citation I!
Learjet 24!
North American Sabreliner!
Commercial Transport Aircraft
Commercial Aircraft of the 1940s !
• Pre-WWII designs!
• Derivatives of military transport and bomber aircraft of WWII!
– Convair 240 (> C-131, T-29)!
– Douglas DC-4 (> C-54)!
– Boeing Stratoliner 377 (from B-29, C-97)!
– Lockheed Constellation 749 (from C-69)!
Trang 13Commercial Propeller-Driven Aircraft of the 1950s !
• Introduction of the turboprop engine !
• Douglas DC-6, DC-7, Lockheed Starliner 1649, Vickers Viscount, Bristol
Britannia, Lockheed Electra 188 !
Commercial Jets of the 1950s !
• Low-bypass ratio turbojet engines !
• deHavilland Comet (1954)!
– 1 st commercial jet transport!
– engines buried in wings!
• Boeing 707 (1957)!
– derived from USAF KC-135 !
– engines on pylons below wings!
– largest aircraft of its time!
• Sud-Aviation Caravelle (1959)!
– 1 st aircraft with twin aft-mounted engines!
Small Commercial Jets of the 1960s !
• Preponderance of aft-mounted 2-
and 3-engine configurations ( BAC
1-11, Douglas DC-9 )!
• Boeing 727 (1963)!
– 1 st with 3 aft-mounted engines!
• Hawker-Siddeley Trident (1964)!
• Boeing 737 (1967)!
Large Commercial Jets of the 1960s !
• Pylon-mounted 4-engine configurations ( Convair 880, DC-8, Stretched DC-8, Boeing 747 )!
• DC-8 design was well-suited to a stretch (fuselage plugs fore and aft of wing!
• B-707 was not!
Trang 14Commercial Jets of the 1970s !
• High-bypass turbofan engines !
• Introduction of the 2/3-engine
jumbo jets!
– Lockheed L-1011!
– Douglas DC-10!
– Airbus A300!
• Supersonic transports!
– BAC/SA Concorde (1972)!
– Tupolev Tu-144 (1977)!
Lockheed L-1011!
Douglas DC-10!
Airbus A300!
BAC/SA Concorde!
Tupolev Tu-144!
Commercial Jets of the 1990s !
• Derivatives of 1980s designs (McDonnell-Douglas MD-11, Boeing 747-400, Airbus A330)!
• First Boeing fly-by-wire design (B-777)!
• First 4-engine Airbus (A340)!
McDonnell-Douglas MD-11!
Boeing 747-400!
Airbus A330!
Boeing 777!
Boeing 247!
Airbus A340!
Daedalus and Icarus Revisited,
23 April 1988
• Human-powered airplane, MIT Daedalus, flies 115 km
from Crete to the mainland (Santorini) in 3 hr, 54 min
• Empty mass = 31 kg
http://en.wikipedia.org/wiki/MIT_Daedalus
http://www.youtube.com/watch?v=l131fSveof8 !
Next Time:
Configuration Aerodynamics
Reading
Flight Dynamics , 65-84!
Virtual Textbook , Part 4,5