Fatal Test Flight Crash in Moisville (F-BAXB)

Flight Details and Test Objective The aircraft departed Paris-Le Bourget Airport at 0750LT for a test flight to evaluate a new type of air scoop. The new scoop was installed on only one engine to enable comparison testing. Five minutes after takeoff, the aircraft reached 4,300 feet. At 0759LT, the starboard engine was stopped, and the test began with a climb on the port engine while the cooling gills were open. ## Test Progression At 0811LT, at 6,980 feet, the crew began the second phase of the test with the port engine cooling gills in the trail position. Level off was completed at 0822LT at 7,900 feet with the cooling gills closed. ## Accident and Casualties About an hour later, while flying at a relatively low speed, the aircraft went out of control and entered a spin. It lost its empennage and crashed in a field in Moisville. The aircraft was destroyed, and all five crew members were killed: René Gallichet, pilot; Louis Pichard, flight engineer; Jacques Légalité, radio navigator; Lucien Goulay, engineer; and Paul Martin, engineer. ## Official Findings The investigation found no mechanical defect that could have been the initial cause. The probable cause was an abnormal flight maneuver made when the crew had difficulty resuming normal flight on two engines. Overspeed, reduction of pitch, or difficulty restarting the engine may have created a dangerous situation, causing the aircraft to stall in dissymmetrical flight. This subjected the airframe to stresses accompanied by buffeting that either alternated or exceeded the design limits of the structure, causing the tail-plane to break off.