Electrics on plane failed as it came in to airport
PILOTS landing a cargo plane at East Midlands Airport had to cope with failing instruments after an electrical fault.
As well as issues in the cockpit, the Boeing 737-400’s automatic brakes failed and the exterior lights went on and off during the final 20 minutes of the flight from Amsterdam.
There had been electrical problems landing at Amsterdam but the 50-yearold pilot, who was new to the company but experienced at flying similar planes, was advised it was safe to continue to East Midlands Airport.
A serious incident report by the UK government’s Air Accidents Investigations Branch said: “During the descent the autopilot disconnected, the copilot’s screens lost power and his flight instruments failed.
“The commander took control and disconnected the auto-throttle.
“Numerous lights on the overhead panel and system annunciation panels illuminated and flashed and multiple aural warnings were generated by the terrain avoiding warning system.
“During the next 20 minutes, and until the aircraft landed, the flight instruments on the co-pilot’s side came on and off numerous times.”
The pilots flew toward runway 27 and the landing gear and controls worked normally, but other systems failed after the plane touched down, knocking the electrical system and further dislodging a critical electrical component.
The report said: “The distracting flashing warning lights and aural callouts continued throughout the approach.
“On landing, numerous aircraft systems failed including the autobrakes (although manual braking remained available), half the exterior lights and the commander’s speed indications on his electronic attitude display indicator.
“On reaching the stand, the crew were unable to connect the electrical ground power to the aircraft system.
“While the flaps were retracted, the flap indication showed them still deployed. No electrical power was available to the cargo door, cargo bay and multiple items on the flight deck.”
An investigation showed a generator control unit (GCU) behind the pilot’s seat had not been installed properly.
West Atlantic UK owned the plane involved in the incident on October 12 last year. The company has 17 aircraft operating out of Sweden and the UK.
The report listed six recommendations for the company to improve the way it carries out and documents the maintenance of its planes.
The report concluded: “This serious incident was caused by the incorrect racking of GCU 2, which moved forward in flight initially causing an intermittent and then total disconnection of the electrical connector.
“The aircraft was not designed to operate with the GCU disconnected.
“The activities surrounding the management of the faults during the previous 12 days, and the actions of the crew in handling the emergency, indicate a weakness in the operator’s procedures.
“Engineers were not always given sufficient time to investigate the faults, with the result fault-finding was often repeated and not finished. Work at a number of locations was not recorded as having been carried out.”