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Pitch-up
In aerodynamics, pitch-up is an uncommanded nose-upwards rotation of an aircraft. It is an undesirable characteristic that has been observed mostly in experimental swept-wing aircraft at high subsonic Mach numbers or high angle of attack. History Pitch-up problems were first noticed on high-speed test aircraft with swept wings. It was a common problem on the Douglas Skyrocket, which was used extensively to test the problem. Before the pitch-up phenomenon was well understood, it plagued all early swept-wing aircraft. In the F-100 Super Sabre it even got its own name, the Sabre dance. In aircraft with high-mounted tailplanes, like the F-101 Voodoo, recovery was especially difficult because the tailplane was placed directly in the wing wake during the pitch-up, causing deep stall (although the T-tail was meant to prevent pitch-up from starting in the first place). Deployment of the braking parachute and a considerable height above the ground were essential for a chance at recovery. D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Douglas D-558-2 Skyrocket
The Douglas D-558-2 Skyrocket (or D-558-II) is a rocket and jet-powered research supersonic aircraft built by the Douglas Aircraft Company for the United States Navy. On 20 November 1953, shortly before the (17 December) 50th anniversary of powered flight, Scott Crossfield piloted the Skyrocket to Mach 2, or more than 1,290 mph (2076 km/h), the first time an aircraft had exceeded twice the speed of sound. Design and development The "-2" in the aircraft's designation referred to the fact that the Skyrocket was the phase-two version of what had originally been conceived as a three-phase program. The phase-one aircraft, the D-558-1, was jet powered and had straight wings. The third phase, which never came to fruition, would have involved constructing a mock-up of a combat type aircraft embodying the results from the testing of the phase one and two aircraft. The eventual D-558-3 design, which was never built, was for a hypersonic aircraft similar to the North Americ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Douglas Skyrocket
The Douglas D-558-2 Skyrocket (or D-558-II) is a rocket and jet-powered research supersonic aircraft built by the Douglas Aircraft Company for the United States Navy. On 20 November 1953, shortly before the (17 December) 50th anniversary of powered flight, Scott Crossfield piloted the Skyrocket to Mach 2, or more than 1,290 mph (2076 km/h), the first time an aircraft had exceeded twice the speed of sound. Design and development The "-2" in the aircraft's designation referred to the fact that the Skyrocket was the phase-two version of what had originally been conceived as a three-phase program. The phase-one aircraft, the D-558-1, was jet powered and had straight wings. The third phase, which never came to fruition, would have involved constructing a mock-up of a combat type aircraft embodying the results from the testing of the phase one and two aircraft. The eventual D-558-3 design, which was never built, was for a hypersonic aircraft similar to the North Americ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
F-101 Voodoo
The McDonnell F-101 Voodoo is a supersonic jet fighter which served the United States Air Force (USAF) and the Royal Canadian Air Force (RCAF). Initially designed by McDonnell Aircraft Corporation as a long-range bomber escort (known as a ''penetration fighter'') for the USAF's Strategic Air Command (SAC), the Voodoo was instead developed as a nuclear-armed fighter-bomber for the USAF's Tactical Air Command (TAC), and as a photo reconnaissance aircraft based on the same airframe. An F-101A set a number of world speed records for jet-powered aircraft, including fastest airspeed, attaining per hour on 12 December 1957. They operated in the reconnaissance role until 1979. Delays in the 1954 interceptor project led to demands for an interim interceptor aircraft design, a role that was eventually won by the B model of the Voodoo. This required extensive modifications to add a large radar to the nose of the aircraft, a second crew member to operate it, and a new weapons bay usin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stall (flight)
In fluid dynamics, a stall is a reduction in the lift coefficient generated by a foil as angle of attack increases.Crane, Dale: ''Dictionary of Aeronautical Terms, third edition'', p. 486. Aviation Supplies & Academics, 1997. This occurs when the critical angle of attack of the foil is exceeded. The critical angle of attack is typically about 15°, but it may vary significantly depending on the fluid, foil, and Reynolds number. Stalls in fixed-wing flight are often experienced as a sudden reduction in lift as the pilot increases the wing's angle of attack and exceeds its critical angle of attack (which may be due to slowing down below stall speed in level flight). A stall does not mean that the engine(s) have stopped working, or that the aircraft has stopped moving—the effect is the same even in an unpowered glider aircraft. Vectored thrust in aircraft is used to maintain altitude or controlled flight with wings stalled by replacing lost wing lift with engine or propeller t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wing Fence
Wing fences, also known as boundary layer fences and potential fences are fixed aerodynamic devices attached to aircraft wings. Often seen on swept-wing aircraft, wing fences are flat plates fixed to the upper surfaces parallel to the wing chord and in line with the free stream airflow, typically wrapping around the leading edge. By obstructing span-wise airflow along the wing, they prevent the entire wing from stalling at once, as opposed to wingtip devices, which increase aerodynamic efficiency by seeking to recover wing vortex energy. As a swept-wing aircraft slows toward the stall speed of the wing, the angle of the leading edge forces some of the airflow sidewise, toward the wing tip. This process is progressive: airflow near the middle of the wing is affected not only by the leading edge angle, but also the spanwise airflow from the wing root. At the wing tip the airflow can end up being almost all spanwise, as opposed to front-to-back over the wing, meaning that the ef ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
F-100 Super Sabre
The North American F-100 Super Sabre is an American supersonic jet fighter aircraft that served with the United States Air Force (USAF) from 1954 to 1971 and with the Air National Guard (ANG) until 1979. The first of the Century Series of USAF jet fighters, it was the first USAF fighter capable of supersonic speed in level flight. The F100 was designed by North American Aviation as a higher-performance follow-on to the F-86 Sabre air-superiority fighter. Adapted as a fighter-bomber, the F-100 was superseded by the high-speed Republic F-105 Thunderchief for strike missions over North Vietnam. The F100 flew extensively over South Vietnam as the air force's primary close air-support jet until being replaced by the more efficient subsonic LTV A-7 Corsair II. The F100 also served in other NATO air forces and with other U.S. allies. In its later life, it was often referred to as the "Hun", a shortened version of "one hundred". Design and development In January 1951, North A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
XF-91 Thunderceptor
The Republic XF-91 Thunderceptor (originally designated XP-91) is a mixed-propulsion prototype interceptor aircraft, developed by Republic Aviation. The aircraft would use a jet engine for most flight, and a cluster of four small rocket engines for added thrust during climb and interception. The design was largely obsolete by the time it was completed due to the rapidly increasing performance of contemporary jet engines, and only two prototypes were built. One of these was the first American fighter to exceed Mach 1 in level flight. A unique feature of the Thunderceptor was its unusual inverse tapered wing, in which the chord length increased along the wing span from the root to the tip, the opposite of conventional swept wing designs. This was an attempt to address the problem of pitch-up, a potentially deadly phenomenon that plagued early high-speed models. The Thunderceptor's design meant the entire wing stalled smoothly, more like a straight-wing design. Design and develo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North American F-100 Super Sabre
The North American F-100 Super Sabre is an American supersonic jet fighter aircraft that served with the United States Air Force (USAF) from 1954 to 1971 and with the Air National Guard (ANG) until 1979. The first of the Century Series of USAF jet fighters, it was the first USAF fighter capable of supersonic speed in level flight. The F100 was designed by North American Aviation as a higher-performance follow-on to the F-86 Sabre air-superiority fighter. Adapted as a fighter-bomber, the F-100 was superseded by the high-speed Republic F-105 Thunderchief for strike missions over North Vietnam. The F100 flew extensively over South Vietnam as the air force's primary close air-support jet until being replaced by the more efficient subsonic LTV A-7 Corsair II. The F100 also served in other NATO air forces and with other U.S. allies. In its later life, it was often referred to as the "Hun", a shortened version of "one hundred". Design and development In January 1951, North Ame ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vortex Generator
A vortex generator (VG) is an aerodynamic device, consisting of a small vane usually attached to a lifting surface (or airfoil, such as an aircraft wing) or a rotor blade of a wind turbine.Wind Turbine Vortex Generators UpWind Solutions. VGs may also be attached to some part of an aerodynamic vehicle such as an aircraft fuselage or a car. When the airfoil or the body is in motion relative to the air, the VG creates a ,Peppler, I.L.: ''From The Ground Up'', page 23. Aviation Publishers Co. Limited, Ottawa Ontario, Twenty Seventh Revised Edition, 1996. which, by removing some part of the slow-moving b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
T-tail
A T-tail is an empennage configuration in which the tailplane is mounted to the top of the fin. The arrangement looks like the capital letter T, hence the name. The T-tail differs from the standard configuration in which the tailplane is mounted to the fuselage at the base of the fin. Advantages T-tails were common in early jet aircraft. Designers were worried that an engine failure would otherwise damage the horizontal tail. The T-tail is very common on aircraft with engines mounted in nacelles on a high-winged aircraft or on aircraft with the engines mounted on the rear of the fuselage, as it keeps the tail clear of the jet exhaust. Rear-mounting the engines keeps the wings clean and improves short-field performance. This was necessary in early jet aircraft with less powerful engines. T-tail aircraft can have better short-field performance, such as on the Avro RJ-85. The disturbed airflow over a lower stabilizer can make control more difficult at lower speeds. Dur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canadian CF-18
Canadians (french: Canadiens) are people identified with the country of Canada. This connection may be residential, legal, historical or cultural. For most Canadians, many (or all) of these connections exist and are collectively the source of their being ''Canadian''. Canada is a multilingual and multicultural society home to people of groups of many different ethnic, religious, and national origins, with the majority of the population made up of Old World immigrants and their descendants. Following the initial period of French and then the much larger British colonization, different waves (or peaks) of immigration and settlement of non-indigenous peoples took place over the course of nearly two centuries and continue today. Elements of Indigenous, French, British, and more recent immigrant customs, languages, and religions have combined to form the culture of Canada, and thus a Canadian identity. Canada has also been strongly influenced by its linguistic, geographic, and ec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
High-lift Device
In aircraft design and aerospace engineering, a high-lift device is a component or mechanism on an aircraft's wing that increases the amount of lift (force), lift produced by the wing. The device may be a fixed component, or a movable mechanism which is deployed when required. Common movable high-lift devices include wing Flap (aeronautics), flaps and Leading-edge slat, slats. Fixed devices include leading-edge slots, leading edge root extensions, and boundary layer control systems. Purpose The size and lifting capacity of a fixed wing is chosen as a compromise between differing requirements. For example, a larger wing will provide more lift and reduce the distance and speeds required for takeoff and landing, but will increase drag, which reduces performance during the cruising portion of flight. Modern passenger jet wing designs are optimized for speed and efficiency during the cruise portion of flight, since this is where the aircraft spends the vast majority of its flight time ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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