Investigators probing the Emirates Boeing 777-300 landing accident at Dubai have yet to explain why the aircraft apparently failed to climb away during a go-around attempt.
But the inquiry is likely to consider whether the event has parallels with an incident involving a 777-300ER which suffered a runway excursion while landing at Munich in 2011.
Preliminary evidence from radio communications indicates that the crew of Emirates flight EK521 acknowledged a go-around instruction after being cleared to land on runway 12L.
This go-around attempt has yet to be confirmed by accident investigators looking into the 3 August crash, which destroyed the jet but from which everyone on board escaped.
The aircraft came to rest on its fuselage underside.
Images of the debris recovery effort show both sets of nose-gear doors on the 777 in the open position, which occurs when the gear is raised or lowered. The reason has not been confirmed but the doors might suggest the landing gear had been in transition at the time.
During a go-around the crew would normally select take-off/go-around thrust, reduce the flap setting, and place the aircraft in a climb attitude, checking that it is gaining height before retracting the landing gear.
Go-around thrust would normally be selected by activating switches mounted on the thrust levers, and would spool up the engines from their low-power setting on approach to the high power needed to climb away.
But according to Boeing flight manuals the take-off/go-around switches on the 777 are designed to be inhibited just at the point of touchdown, and a go-around in these circumstances would require manually advancing the thrust levers.
German investigators looking into a Singapore Airlines 777-300ER excursion at Munich in November 2011 said the crew had attempted a go-around, after the jet drifted just before touchdown.
But this attempt was unsuccessful, despite evidence that the crew had tried activating the take-off/go-around switches and had called for the go-around flap setting. The inquiry has yet to reach conclusions on the incident.
The Emirates 777 came to rest at the far end of runway 12L which – if the approach was otherwise normal – might indicate that the aircraft managed to stay airborne for a period before sinking onto the runway.
Investigators have not given any details about the status of the engines or the landing gear at the time of the accident. The accident occurred in particularly hot summer conditions, at around 12:45, when the air temperature was around 49°C.
Source: Cirium Dashboard