About Flight 411:
Aeroflot flight 411 took off from Moscow-Sheremetyevo Airport (SVO) at 00:33 on a flight to Dakar (DKR), Senegal and Freetown (FNA), Sierra Leone. Eight seconds after raising the landing gear the fire alarm for engine no. 1 activated. The crew shut down the engine in accordance with the Flight Manual and used the three stages of fire suppression systems. After 30 seconds another alarm activated, signalling a fire in engine no. 2. This engine was also shut down. At that time the speed was 320 km/h, height about 160 m, landing gear was retracted, and flaps were in takeoff position (30°). The crew had initiated a right hand turn, which was recommended in case of a failure of the left hand engines.
The crew were not able to maintain altitude. The speed decreased, increasing the angle of attack and slip. The airplane stalled at a height of 75 m and came down in a 70° left bank and a pitch angle of -20°. The plane crashed in swampy woods.
Investigation revealed that both fire alarms were false. Hot air from a ruptured pipe of the air conditioning system had blown on the temperature sensors.