Date & Time: Aug 26, 1993 at 1430 LT
Type of aircraft:
Dassault Falcon 10
Landing (descent or approach)
Saskatoon – Great Falls – Hailey
United States of America
Crew on board:
Pax on board:
Captain / Total hours on type:
Aircraft flight hours:
Because of the failure of the thrust reverser relay circuit board, the thrust reversers failed to deploy when selected by the pilot. Because the reversers failed to deploy, the 'reversers in transition' lights, and the 'reversers deployed' lights did not illuminate. Even though the aircraft flight manual warns against moving the reverser throttle levers into the power range without the illumination of these lights, the pilot did so anyway. The pilot continued to select reverse power even after the activation of the throttle mismatch warning horn, resulting in an increase in forward thrust while attempting to stop. During this sequence of events the second-in-command moved the parking brake lever to full override, locking the main wheel brakes and overriding the antiskid system.
The pilot-in-command's improper procedures. Factors include failure of an electrical relay, inoperative thrust reverser, poor crew coordination, and the second-in-command's improper procedures.