Incident Overview
The Boeing SA.307 Stratoliner, registration F-BELZ, arrived at Bastia (BIA), France, from Nice (NCE) at 05:25 UTC. It departed again at 11:49 for the return flight via Ajaccio (AJA), Corsica, and was cleared for a cruising altitude of FL120, estimating Ajaccio at 12:20 UTC. Last radio contact occurred at 12:09 when the crew replied to weather and active runway information from Ajaccio Approach. At 12:12, the aircraft flew into a sheer rock face of Monte Renoso, located 45 km from the Ajaccio VOR on the 048 radial. Impact was at an altitude of 2,285 m (7,500 feet), about 50 m (165 feet) below the summit. The aircraft rebounded and fell about 100 m down the slope.
Crew and Passengers
All 25 occupants were killed, including members of the Bastia Basketball team, who were traveling to Nice for the National Championship. The crew comprised pilot Roger Mercier, copilot Fernand Delime, and mechanic Antoine Blois. The aircraft was totally destroyed.
Investigation and Probable Cause
The official investigation attributed the accident to a series of crew errors: insufficient flight preparation and a serious error in estimating flight duration; failure to observe the planned cruising altitude; inadequate navigation checks resulting in incorrect position estimation; failure to maintain safety altitude; and premature descent into instrument flight conditions. These errors were made possible by a lack of flight supervision by the operator and a lack of correct route instructions for the Bastia-Ajaccio segment. The Board concluded that the crew did not have necessary instructions for the route via the turning point. Even if the instructions were issued before the accident and were available, the Board considered them inaccurate and dangerous because they did not specify the altitude at the turning point and provided a flight time incompatible with attaining safety altitudes. Additionally, crew fatigue may have been a factor, as their flight activity was strenuous in the three days preceding the accident, though regulations were observed.