Near miss compilation - worth a watch

[calypso]

Some interesting pucker factor moments here.
Love to know what is going on in the Airbus undercarriage clip.
Bizarre!

http://www.youtube.com/watch?v=bM4G1Toe3h0

[Motormouse]

Love to know what is going on in the Airbus undercarriage clip.

Part of the certification tests require a maximum weight V1 abort using brake action only (reversers are not allowed), they know the tyres will fail and brakes start a fire, its part of the test.
The tyres blow-out as their temperature (heated by the now red-hot brakes) increases beyond the limit of the temperature fusible plugs installed in each wheel. In the video the situation is compounded by the fire numpty spraying cold water on hot components, so you get a thermal shock explosion.
IIRC there is a time limit before which the fire brigade are not allowed to interfere or attempt to put out the fire, to simulate the time it would take an average airport fire brigade to respond.

ttfn

Pete

[calypso]

Thank you Pete.
I suspected as much. It's just that the crew did not seem to have that cool and professional approach I normally associate with test pilots.

[Chris Trott]

Actually, they're not supposed to catch fire like that. The plane failed the test, had to have serious structural repairs, and 2 additional attempts before it passed. The point where it failed was when the first tire exploded on the central gear after the thermal plug on the wheel failed to release the air in a controlled manner. It broke the brake, 2 wheel hubs (that's the part that rolls away), and fractured the brake lines that started the fire. At that point, the test was supposed to be over. Unfortunately, the test crew, even knowing this, tried to make it sound like it was nothing, told the fire crew to not attack the fire, but eventually the Fire Captain told the crew to disregard the Airbus crew's directions and put out the fire.

[Motormouse]

Just to explain a bit more, a brake fire after the test is permitted if the manufacturer can demonstrate it is contained,
and the amount of fluid released is limited. FAA AC 25.735 is the US certification requirement for aircraft brakes, over here in EU we have EASA equivalent.

As Mr T says,

they're not supposed to catch firelike that

Ttfn

Pete

[NigelC]

777 RTO test

http://www.youtube.com/watch?v=wXpjBxD0Rhg