Search results
Results from the WOW.Com Content Network
At the critical angle of attack, upper surface flow is more separated and the airfoil or wing is producing its maximum lift coefficient. As the angle of attack increases further, the upper surface flow becomes more fully separated and the lift coefficient reduces further. [7] Above this critical angle of attack, the aircraft is said to be in a ...
The High Alpha Research Vehicle was a modified American McDonnell Douglas F/A-18 Hornet used by NASA in a three-phase program investigating controlled flight at high alpha (angle of attack) using thrust vectoring, modifications to the flight controls, and with actuated forebody strakes. The program lasted from April 1987 to September 1996. [1] [2]
At the moment of liftoff, when angle and velocity are both zero, the theta-dot equation is mathematically indeterminate and cannot be evaluated until velocity becomes non-zero shortly after liftoff. But notice at this condition, the only force which can cause the vehicle to pitch over is the engine thrust acting at a non-zero angle of attack ...
An angle-of-attack indicator for light aircraft, the "AlphaSystemsAOA" and a nearly identical "lift reserve indicator", are both pressure-differential instruments that display margin above stall and/or angle of attack on an instantaneous, continuous readout. The General Technics CYA-100 displays true angle of attack via a magnetically coupled vane.
(NASA) The Herbst maneuver (also known as a J-turn [1] [2]) is an air combat maneuver that uses post-stall technology such as thrust vectoring and advanced flight controls to achieve high angles of attack. [3] The Herbst maneuver allows an aircraft to quickly reverse direction using a combination of high angle-of-attack and rolling.
The guidance program is a precalculated lookup table of pitch vs time. Control is done with engine gimballing and/or aerodynamic control surfaces. The pitch program maintains a zero angle of attack (the definition of a gravity turn) until the vacuum of space is reached, thus minimizing lateral aerodynamic loads on the vehicle.
Rogallo wing kites control pitch with a bridle that sets the wing's angle of attack. A bridle made of string is usually a loop reaching from the front to the end of the center strut of the A-frame. The user ties knots (usually a girth hitch) in the bridle to set the angle of attack. Mass-produced rogallo kites use a bridle that's a triangle of ...
There are various methods to estimate or "synthesize" airspeed, angle of attack, and angle of sideslip without directly using the measured air data. For example, synthetic airspeed can be computed by using the ground velocity, angle of attack, wind velocity, airplane's pitch attitude and heading. The ground velocity is usually provided by GPS ...