(August. 13 1999) --The F-22 Raptor successfully met another test milestone recently while flying a 2.5 hour sortie over Edwards Air Force Base, Calif. The F-22 managed to fly beyond 26 degrees angle of attack for the first time. This achievement officially marked the beginning of a new testing phase in the Raptor program -- a regime of rigorous high angle of attack flight profiles. Angle of attack or (AOA) is the measurement of the angle between the wing of the plane and the flow of air as it flies through the air.

High angle of attack testing, also known as high alpha testing is necessary to evaluate the agility and maneuverability of the F-22. The testing program requires the F-22 to perform controlled flight at very slow speeds. It is also interesting to note that the F-22 is the first production fighter designed to manuever at high angles of attack "with abandon."

Unlike the first F-22 (Raptor 01), the Raptor 02 has been equipped to complete the high alpha test missions and enter areas of the flight envelope no other fighter can safely enter. In case of a mishap, a deployable stabilization chute is located between the vertical stabilizers. The pilot manually deploys this chute in case an unforeseen flight condition develops and jettisons it when he regains control of the aircraft. There should be no trouble at all recovering from a stall in the F-22 because of its powerful Pratt & Whitney F119-PW-100 engines and their proven demonstration of having a sufficient stall margin.

The F-22 is being designed to fly at nearly a remarkable 60 degrees AOA. The USAF current air superiority fighter the F-15 can only sustain 30 deg AOA.

Over the next few months, the F-22 will be tested throughout its entire high angle of attack flight envelope. The aircraft is being purchased by the Air Force to replace the aging F-15 air superiority fighter. (Courtesy of Air Force Materiel Command News Service & edited in my own words)