A preliminary report on the 6 November Luxair Fokker 50 fatal accident on approach to Luxembourg Airport reveals that the propellers went into ground fine pitch and the engines stopped within seconds of each other while the aircraft was still above 2,000ft (610m). Of the 22 people on board, the captain and a passenger survived the crash.
The aircraft was intercepting an instrument landing system approach to Luxembourg's runway 24 with the runway visual range given as 300m in fog, the permitted minimum. Flight data recorder (FDR) information indicates a normal descent with the engines at idle and the flap set to 10°, until the crew put the landing gear down at 09:05:16. Within a second the left propeller adopted a negative pitch of 10° followed by the right propeller a second later. At 09:05:26 the left engine shut down, and both the FDR and cockpit voice recorder stopped operating a second after that. Luxembourg transport department investigators later determined the right engine had also shut down, depriving the recorders of power.
The interim report does not reach a conclusion, but it mentions two Fokker service bulletins (Flight International, 26 November-2 December). One, issued in December 1994, warns that a solenoid switch controlling the power lever locks that prevent selection of the beta (ground idle) pitch range in flight can be triggered inadvertently, removing the locks. The other, issued in February 1999, requires a modification to the touchdown switch connection with the brake anti-skid system, because intermittent brake operation after selection of gear down can induce an electric current in the touchdown switch cable. The Luxair aircraft did not embody this modification.
The aircraft crashed 700m to the right of the runway extended centreline, 3.5km (2nm) short of the threshold.
Source: Flight International
