The crew of the Embraer Legacy 500 were carrying out a private flight from Moscow-Domodedovo airport, bound for Paris-Le Bourget airport.
At Moscow, a thin film of ice covered the aeroplane and the crew had it de-iced. As icing conditions were prevailing at Moscow airport, the crew set the selector of the ice protection control panel to ALL before starting up the engines. During their start-up, the A-I WINGSTAB FAIL message appeared on the EICAS. The crew tried to reinitialize the system by pressing the WINGSTAB pushbutton and then using the ICE PROT MODE selector. The failure message continued to be displayed.
Around five minutes after take-off, the STALL PROT ANTICIPATE warning message appeared on the EICAS and remained on the screen until the end of the flight.
The captain was PF and the first-officer PM for the arrival at Le Bourget airport. The METARs did not indicate icing conditions. The crew performed the ILS 27 approach at a speed of between 120 and 130 kt.
At an altitude of 2,200 ft, while the aeroplane was on the ILS glide path, the AOA limiter protection activated itself and the AP automatically disengaged. The aeroplane passed under the glide slope and a “glide slope” warning sounded. The captain then increased thrust and levelled off in order to return to the approach path. The AOA limiter protection disengaged itself and the crew re-engaged the AP.
At around 1,000 ft QNH, the AOA limiter protection engaged itself again and the AP disengaged. The first officer told the captain to keep the speed above the red tape corresponding to the minimum speed authorized by the protection. This protection limits the angle of attack and did not allow the captain to sufficiently increase the aeroplane’s pitch attitude in order to flare, despite making a full nose-up deflection on the sidestick.
The aeroplane touched down with a rate of descent of around 1,350 ft/min and a load factor of 4 g. The right main landing gear ruptured and the upper rear hinge made a hole in the upper surface of the wing.
The crew undertook the flight despite the presence of the A-I WINGSTAB FAIL message and icing conditions at departure from Moscow. The occurrence of the failure is linked to the activation of the ice protection system in the ALL position before engine start-up. The procedure associated with this failure, as written at the time of the accident, did not enable the crew to reinitialize the ice protection system. The BEFORE TAKEOFF procedure and then the consultation of the MEL should have resulted in the crew postponing the flight.
During the climb, the appearance of the STALL PROT ANTICIPATE message on the EICAS informed the crew of the increase in AOA limiter protection activation speeds. The associated procedure should have led the crew to increase the reference speed by 30 kt during the approach.
The approach speed selected by the crew was less than the AOA limiter protection activation speed, this protection prevented the captain from carrying out the flare.
Download the report(s) by clicking on the link(s) below: