Emirates 777 Dubai wheels up
Posted: Wed Sep 07, 2016 8:32 amBelow is an article from the magazine 'Flight Global' and pretty much sums up what I thought probably happened.
It is one of the problems with automated flight systems, especially the Autothrottle on Boeings, and knowing which modes they will or not work in.
Asiana was the other example. Because they normally perform so well there is an increasing over reliance on them.
I wonder if they were ex Airbus pilots whereby the thrust levers don't move ...another trap with changing radically different aircraft types.
Flight Gobal magazine
David Kaminski-Morrow
Investigators have disclosed that the Emirates Boeing 777-300 destroyed in an accident at Dubai was attempting a go-around after a long landing.
The aircraft had touched down some 1,100m (3,600ft) from the threshold of runway 12L after a tailwind on approach started transitioning to a headwind.
General Civil Aviation Authority investigators state that, as the 777 touched down with its engines at idle power, the crew received an aural warning that the jet had landed long.
The crew opted to execute a go-around and the aircraft became airborne 4s after the warning.
Its flaps started to retract to the ‘20’ position – the normal go-around setting – some 4s after that, and the landing-gear lever was activated 2s later.
Crucially, the inquiry does not mention whether the take-off/go-around switch, normally used to command go-around thrust from the engines, was activated.
But the investigators point out that these switches on the 777 are inhibited once the aircraft’s landing-gear touches down. In this situation, the crew must manually advance the thrust levers to command go-around power.
The inquiry indicates that the Emirates aircraft was still operating with idle thrust, and decelerating, as it attempted to climb away.
It was subject to a headwind and reached a height of about 85ft before it began to sink back down to the runway.
Both pilots realised the airspeed was decreasing and the thrust levers were suddenly pushed from the idle setting to the fully-forward position.
But the thrust command was too late to arrest the 900ft/min sink and the aircraft – pitched 9.5° nose-up and travelling at 125kt – struck the runway with its aft fuselage about 1s after the engine power began to increase.
As the landing-gear was still undergoing retraction, the 777 contacted the runway with its Rolls-Royce Trent 800 engines, one of which detached as the aircraft slid to a halt.
The landing-gear would normally only be retracted during a go-around once the crew had confirmed that the aircraft had achieved positive climb.
Investigators have not disclosed the pilots’ communications in this regard, nor indicated whether they might have misinterpreted the initial climb away from the runway before retracting the landing-gear.
The aircraft, which was arriving from Thiruvananthapuram as flight EK521, was destroyed by fire but all 282 passengers and 18 crew members escaped.
General Civil Aviation Authority investigators, who have released the initial details of the crash in a preliminary bulletin, are continuing their inquiries to establish the cause of the accident.
It is one of the problems with automated flight systems, especially the Autothrottle on Boeings, and knowing which modes they will or not work in.
Asiana was the other example. Because they normally perform so well there is an increasing over reliance on them.
I wonder if they were ex Airbus pilots whereby the thrust levers don't move ...another trap with changing radically different aircraft types.
Flight Gobal magazine
David Kaminski-Morrow
Investigators have disclosed that the Emirates Boeing 777-300 destroyed in an accident at Dubai was attempting a go-around after a long landing.
The aircraft had touched down some 1,100m (3,600ft) from the threshold of runway 12L after a tailwind on approach started transitioning to a headwind.
General Civil Aviation Authority investigators state that, as the 777 touched down with its engines at idle power, the crew received an aural warning that the jet had landed long.
The crew opted to execute a go-around and the aircraft became airborne 4s after the warning.
Its flaps started to retract to the ‘20’ position – the normal go-around setting – some 4s after that, and the landing-gear lever was activated 2s later.
Crucially, the inquiry does not mention whether the take-off/go-around switch, normally used to command go-around thrust from the engines, was activated.
But the investigators point out that these switches on the 777 are inhibited once the aircraft’s landing-gear touches down. In this situation, the crew must manually advance the thrust levers to command go-around power.
The inquiry indicates that the Emirates aircraft was still operating with idle thrust, and decelerating, as it attempted to climb away.
It was subject to a headwind and reached a height of about 85ft before it began to sink back down to the runway.
Both pilots realised the airspeed was decreasing and the thrust levers were suddenly pushed from the idle setting to the fully-forward position.
But the thrust command was too late to arrest the 900ft/min sink and the aircraft – pitched 9.5° nose-up and travelling at 125kt – struck the runway with its aft fuselage about 1s after the engine power began to increase.
As the landing-gear was still undergoing retraction, the 777 contacted the runway with its Rolls-Royce Trent 800 engines, one of which detached as the aircraft slid to a halt.
The landing-gear would normally only be retracted during a go-around once the crew had confirmed that the aircraft had achieved positive climb.
Investigators have not disclosed the pilots’ communications in this regard, nor indicated whether they might have misinterpreted the initial climb away from the runway before retracting the landing-gear.
The aircraft, which was arriving from Thiruvananthapuram as flight EK521, was destroyed by fire but all 282 passengers and 18 crew members escaped.
General Civil Aviation Authority investigators, who have released the initial details of the crash in a preliminary bulletin, are continuing their inquiries to establish the cause of the accident.
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