Accession Number : ADA319981

Title :   Volume II. Flying Qualities Flight Testing Phase. Chapter 10: High Angle of Attack.

Corporate Author : AIR FORCE TEST PILOT SCHOOL EDWARDS AFB CA

PDF Url : ADA319981

Report Date : MAY 1991

Pagination or Media Count : 156

Abstract : From the designer to the pilot, everyone associated with the flying qualities of high performance military aircraft, particularly the fighter or attack variety, is or should be aware of the importance of the high angle of attack flight regime. It is here that the aircraft will spend a significant amount of its time when performing the mission for which it was designed. It is here that the aircraft must display its most outstanding performance. It is also here that the aircraft, when pushed beyond its limits of controllability, can seemingly defy all laws of physics and principles of flight with which its surprised and often bewildered pilot is acquainted. The frequency of inadvertent loss of control at high angle of attack is such that many combat aircraft pilots are becoming firmly convinced that all pilots may be divided into two categories: those who have departed controlled flight, and those who will. Most thoroughly convinced are those pilots who fall into the former category. The unfortunate fact concerning departure from controlled flight at high angle of attack is that many aircraft and pilots are lost each year due to failure to recover from the out-of-control flight condition. The circumstances surrounding the losses are varied. Departures from controlled flight may occur unintentionally during high-g maneuvers or intentionally during a nose-high deceleration to zero airspeed in an attempt to gain an advantage over an opponent in combat maneuvering; the aircraft may spin and the gyration be identified too late for recovery or a steep spiral may be mistakenly identified as a spin, causing recovery controls to be misapplied. Whatever the circumstances, departures from controlled flight result all too often in catastrophe. For this reason, test pilots in particular must be familiar with every facet of the high angle-of-attack flight regime.

Descriptors :   *ANGLE OF ATTACK, *FLIGHT MANEUVERS, PRESSURE GRADIENTS, MANEUVERABILITY, ROLL, PITCH(MOTION), YAW, AERODYNAMIC STABILITY, TURBULENT FLOW, VORTICES, STALLING, AERODYNAMIC LOADING, AERODYNAMIC DRAG, FLIGHT ENVELOPE, AERODYNAMIC LIFT, DOWNWASH, ASPECT RATIO.

Subject Categories : Aerodynamics

Distribution Statement : APPROVED FOR PUBLIC RELEASE