Boeing 777 loses all power, electronics and crashlands at Heathrow

[Q Classic]

Trust the man with the beard. He looks like he knows his ****.

(Sounds reasonable, too.)

[Asher]

It's my understanding that you need to be at a sufficient speed for the turbine prop to power sufficiently, which the plane may not be if it slowed down for landing.

[BlackCat]

Nah, speed at landing is probably enough, but one thing is activating such a device at 3 km altitude, another is at 50 m while landing.

[Asher]

Originally posted by BlackCat
Nah, speed at landing is probably enough, but one thing is activating such a device at 3 km altitude, another is at 50 m while landing.

What difference does altitude make when the whole reason the device works is velocity?

[BlackCat]

Originally posted by Asher

What difference does altitude make when the whole reason the device works is velocity?

No offense, but there could be that slight difference that at high altitude, the device might be activated before the situation becomes "interesting" wich might not be the case seconds before a landing.

[Proteus_MST]

Originally posted by Asher

What difference does altitude make when the whole reason the device works is velocity?

One thing might be the amount of remaining time.
At FL 100 you will remain in the air for a long time. Enough time to activate the device and have it running to supply your plane with energy.
At 150 ft however you are only seconds from Touchdown. I don´t know how many seconds pass between activation of this secondary power generator and the time when it really produces power, but I suspect that at this altitude it might come too late to produce power before the plane hits earth

[Asher]

A witness on the BBC reported seeing the ram air turbine deployed as it came in to land...

I don't know why you guys think it takes more than a few seconds for a ram air turbine to be deployed.

[Asher]

This also backs that up: http://www.flightglobal.com/articles...-heathrow.html

The crew managed to control the descent to a touchdown with wings level, on grass just over the perimeter fence at Heathrow, on the 27L extended centreline. The gear was down, flaps were set at about 20°, and the indications are that the crew had started the auxiliary power unit.

[Proteus_MST]

We don´t doubt that it only takes a few seconds.
We just say that depending on your altitude these few seconds might be more than the time you have to execute the touchdown in a controlled manner. Especially if you make your approach via ILS.

But sounds like the power failed already at an early time of the approach if they even managed to get the APU running in flight.

Will get interesting to know wether the powerloss was caused by failures in construction or by bad maintenance.

[Heraclitus]

I wonder how this thread would have turned out if it was an Airbus plane that nearly avoided disaster.

[Asher]

Originally posted by Proteus_MST
We don´t doubt that it only takes a few seconds.
We just say that depending on your altitude these few seconds might be more than the time you have to execute the touchdown in a controlled manner. Especially if you make your approach via ILS.

But sounds like the power failed already at an early time of the approach if they even managed to get the APU running in flight.

Will get interesting to know wether the powerloss was caused by failures in construction or by bad maintenance.

Or lack of fuel?

[OneFootInTheGrave]

seen this now, and WHOA... that was as close as it gets... the pilot was pale I bet , but he needs to be made a sir by the Queen

[Asher]

Originally posted by OneFootInTheGrave
seen this now, and WHOA... that was as close as it gets... the pilot was pale I bet , but he needs to be made a sir by the Queen

Strangely enough, BBC reports the pilot was extremely pale...

[Proteus_MST]

Originally posted by Asher


Or lack of fuel?

Doesn´t sound like this:

An airport worker told the BBC the Boeing 777 pilot, named later as Peter Burkill, 43, said he had lost all power and had to glide the plane in to land.

...

The worker also said the pilot had told him all the electronics had also failed.

"He said he had no warning - it just went," the worker added.

"It's a miracle. The man deserves a medal as big as a frying pan."

One would assume that the pilots would know in advance when they´re running low on fuel and would also inform the tower, so that they get a higher priority in the list of planes waiting to land.

[dannubis]

Did Asher find a way to utter his inferiority complex on European engineers again ?

OTOH, no cusualties