Pilots forced to apply maximum thrust after aircraft failed to respond to control inputs
An Emirates Airbus A340-300 ran 150m (490ft) off the end of the runway before getting airborne at Johannesburg airport on 9 April after the aircraft initially failed to respond to control inputs for rotation, according to an aircraft safety report (ASR) filed by the crew.
The pilots managed to get the aircraft airborne from the overrun area of runway 21R by applying take-off/go-around (TOGA) thrust, but only after the A340 had struck threshold and approach lighting, damaging its tyres, brakes and flaps. The crew dumped fuel and returned to the airport, where they landed safely on runway 21L.
Emirates says the aircraft (A6-ERN) began its take-off roll on runway 21R with normal flap set, bound for Dubai with 14 crew and 216 passengers on board. Air temperature was 15°C (59°F).
According to the ASR filing, at the rotate call, "the pilot flying applied rearward sidestick, and for approximately six or seven seconds the aircraft nose did not move upward", so the crew selected TOGA. Johannesburg's Jan Smuts airport has long runways because of its elevation (5,560ft/1,700m). Runway 21R from which flight EM764 took off is 4,420m long.
The airport says 25 runway threshold and approach lights, and part of the runway surface, were damaged as the aircraft went over the end of 21R, which has a relatively clear, level overrun. Once airborne, the initial climb and thrust reduction routine proceeded normally, but as the crew selected flap retraction the electronic centralised aircraft monitor (ECAM) warned that the flaps had locked while still partially deployed. The aircraft's safety system is designed to prevent damaged flaps becoming asymmetric.
Air traffic control reported that runway end lights had been damaged and the A340 appeared to have travelled 150m across unpaved ground in the overrun. The crew says there was no other ECAM warnings, so they returned to the airport, having used the checklist for an approach in a non-standard configuration. During the landing run, when the speed was "about 70kt [130km/h]", the main braking system failed and the A340 halted just before the runway end.
Emirates says the South African Civil Aviation Authority is overseeing an investigation, aided by Airbus and the Dubai authorities. The seven-year-old ex-Singapore Airlines A340 entered service with Emirates in February and was last week still under repair.
DAVID LEARMOUNT / LONDON & HILKA BIRNS / CAPE TOWN