The Russia-based Interstate Aviation Committee (MAK) has called on the nation’s Trade and Industry Ministry to develop a system for ensuring that aircraft manufacturers meet existing regulations for production, licensing and testing, following the fatal crash of an L-44 amphibian light aircraft near Moscow in June 2010 that killed three people.
MAK’s report on the accident also called for checks in particular on small firms producing aircraft in limited numbers. It called on Chaika, the manufacturer of the L-44, to introduce additional technical and construction documentation for the aircraft, and consider installation of stall warning indication and an additional source of air pressure data for the aircraft’s airspeed indicator (ASI).
The aircraft’s user documentation also lacked information on action in the event of an airspeed indicator failure.
The accident took place after take-off from a lake in Moscow Region, in good weather. The aircraft suffered damage during take-off, including structural failures near the pilot’s seat. The two passengers were not wearing their seat-belts. The aircraft lifted off from the surface of the water at a lower speed than required, banked left and descended, and hit the ground nearby. The fuel system ruptured, causing a fire that destroyed the aircraft almost entirely.
The report cites the primary reason for the crash as the pilot lifting the aircraft from the surface of the lake at too low an airspeed, due to damage to a feed pipe for the aircraft’s aneroid ASI (photo 2). That damage occurred when the pilot’s seat shifted due to structural damage caused by an initial impact with the water on take-off.
The right-hand ASI was indicating zero airspeed during the take-off when the aircraft, according to an on-board Garmin GPS, was in fact travelling at 104 km/h.
The pilot then carried on with the take-off after the aircraft lost lift and hit the water, causing further structural damage. The initial impact with the water during take-off allowed water into the cabin, causing a rearward shift in centre of gravity.
The aircraft then continued to gain height and failed to retract its flaps, causing a loss of airspeed and subsequent stall.
Source: FlightGlobal.com
