Narrative:The DC-7 took off from Bordeaux runway 23 at 22:23 UTC for a flight to Bamako and Abidjan. After leaving the ground and reaching a height of abuot 30m, the aircraft overflew a zone without luminous ground markings. The aircraft didn't gain altitude and collided with pinetrees 2950m from the start of the takeoff.
PROBABLE CAUSE: "The Board considered that the accident was probably caused by the most unfavourable combination of several of the factors set forth under "Theories considered as to the cause of the accident."
The reconstructed flight showed that during the first segment of climbout and during a very short critical phase [about 10sec beginning 40sec after full throttle] a slight increase in speed will produce a considerable decrease in rate of climb or even a slight loss of altitude.
In view of the rapid sequence of cockpit operations during this phase, together with the rapid variation in flight parameters, and the lack of precision - even inaccuracy - of readings of certain instruments, and lacking time reference and external visual references, a pilot may follow a line of flight that will bring the aircraft back near the ground if, during this period, optimum climbing speed is not maintained and the altimeter is not carefully watched."
Sources:
» ICAO Circular 64-AN/58 (41-50)
Photos
Map
This map shows the airport of departure and the intended destination of the flight. The line between the airports does
not display the exact flight path.
Distance from Bordeaux-Mérignac Airport to Bamako Airport as the crow flies is 3630 km (2269 miles).