Poor handling of Tu-154 at high altitude cited by investigators probing August crash
Russian investigators have concluded that a lack of adequate training in handling the Tupolev Tu-154 at high altitudes and angles of attack led a Pulkovo Airlines crew to stall their aircraft and enter a fatal flat spin.
The aircraft, operating the domestic Anapa-St Petersburg route on 22 August last year, failed to recover from the spin and, at a high rate of descent, struck the ground near Donetsk in Ukraine.
All 170 passengers and crew on board the Tu-154M (RA-85185), were killed.
During the flight the tri-jet had climbed to high altitude near turbulent thunderstorm activity, and was subjected to pitch changes that took it beyond the stall limits.
Russia's Interstate Aviation Committee (MAK) says the crew had not received sufficient training or simulation experience on the specific procedures, including use of the trim control, necessary to maintain longitudinal stability under these conditions.
"Absence of control over the airspeed and the non-compliance with flight operation instructions to prevent the aircraft's entry into a stall, with unsatisfactory crew intervention, made it impossible to avoid transition to a catastrophic situation," says MAK.
The organisation has made several recommendations to improve pilot training and has urged crews to take account of operational limitations when selecting a flightpath to negotiate storm cells.
During the inquiry MAK conducted simulations and test flights to examine the behaviour of Tu-154 aircraft at high angles of attack, in a bid to determine how the emergency developed. Investigators also closely studied previous similar accidents involving Tu-154s, including the loss of an Aeroflot flight in July 1985 over Uchkuduk in Uzbekistan.
St Petersburg-based Pulkovo Airlines has since merged with Russian government carrier Rossiya, under whose name the combined airlines operate.
Aeroflot intends to phase out its Tu-154s by 2010, having approved the withdrawal of all Tu-134s from its fleet this year. Aeroflot is planning to replace the Tu-154s and Tu-134s with Airbus A320-family aircraft and Sukhoi Superjet 100s it has on order.
The airline has been under pressure from SkyTeam to withdraw older jets. It will remove Tu-134s by 1 January 2008 and will withdraw the Tu-154s by the end of the decade. Aeroflot has had 14 76-seat Tu-134s in service for 40 years and its fleet includes 28 Tu-154s.
Source: Flight International
