Brakes activated before Vietnam Airlines 787 overran Munich runway, report finds
HANOI, Sept 29 (Reuters) - A Boeing BA.N 787-9 operated by flag carrier Vietnam Airlines HVN.HM recorded repeated brake inputs during takeoff before overrunning a runway and striking approach lighting at Munich Airport last month, according to an interim report by German investigators.
The plane, operating a scheduled flight from Munich to Hanoi on August 15 with 271 passengers, 12 cabin crew and four pilots on board, sustained substantial damage but no injuries were reported, according to the German Federal Bureau of Aircraft Accident Investigation (BFU).
Flight recorder data showed movement of the left-side brake pedals and corresponding brake-system activation shortly after the aircraft began its takeoff run. A second braking event was recorded moments before rotation, according to the BFU report.
The pilot in the left seat, a 64-year-old with 27,182 flying hours, was flying the plane at takeoff, it said.
The report did not say whether the brake inputs were caused by pilot action or a technical malfunction.
Investigators said they had secured brake-related components and other system parts from the aircraft for examination.
The aircraft's speed remained near 168 knots (311 kph) for about 18 seconds during the takeoff roll before engine thrust was increased by the co-pilot in the right seat shortly before liftoff, according to the BFU report.
The jet rotated below its calculated takeoff speed and became airborne from a grass area beyond the runway and its clearway. Its tail section and both main landing gear struck parts of the airport's approach-lighting system, causing substantial damage to the aircraft, the report added.
The flight's designated pilot in command, who had been sitting in the left jump seat at takeoff, took over the controls after the plane became airborne, it said.
The crew dumped 62 metric tons of fuel before returning to Munich, where the aircraft landed safely about two hours later. Four tyres on the left main landing gear were found damaged after landing.
The BFU said the cockpit voice recording covering the takeoff was unavailable because it had a two-hour recording time and had been overwritten.
The investigation into the Munich accident is ongoing and no final conclusions have been reached. Experts say air accidents usually result from a combination of factors and investigations can take at least a year to complete.
Vietnam Airlines did not immediately respond to a request for comment