Narrative:The Canadair plane was on a test flight out of Wichita, KS to evaluate flying qualities in a new 8deg. takeoff flap setting and to demonstrate compliance with US 14 CFR 25:177 rules. The aircraft lost control during a low speed steady-heading sideslip test manoeuvre at FL120. The crew were to end a Steady Heading Sideslip (SHSS) manoeuvre at a 15deg sideslip, but continued to 21deg. at full rudder. The plane rolled rapidly through 360deg and entered a deep stall. As it descended through 8000 feet the captain requested the co-pilot to deploy the anti-spin parachute, which he complied with. The co-pilot however, didn't close the jaws (which connect/disconnect the parachute from the airplane) before chute deployment. The chute thus fell free of the plane. Control was not regained and the aircraft crashed and skidded for about 200 yards through several cornfields.
PROBABLE CAUSE: "The captain's failure to adhere to the agreed upon flight test plan for ending the test manoeuvre at the onset of prestall stick shaker, and the flight crew's failure to assure that all required switches were properly positioned for anti-spin chute deployment. A factor which contributed to the accident was the inadequate design of the anti-spin chute system which allowed deployment of the chute with the hydraulic lock switch in the unlocked position. (When in the unlocked position, the hooks clasping the chute shackle to the airframe are open.)"
» Air International September 1993, p.127
» Aviation Week & Space Technology 02.08.1993 (39-40)
» NTSB Safety Recommendation A-94-101
» Scramble 170