"Rick" wrote in message
ink.net...
Steven Shelikoff wrote:

aircraft brakes are in many cases under engineered since they
depend so much on engine braking to slow down.

Incorrect. The brakes on transport category aircraft are certified to
stop the aircraft on the runway remaining after a rejected takeoff at
the highest speed it would still be on the ground (V1) without using
thrust reversers. Thrust reversers provide little braking at high speeds
anyway.

Rick

The brakes *will* stop the plane at V1. Other than that, there may be
problems. The company I work for sells parts for "retriever kits." They use
these kits to recover aircraft after they deploy the brakes during an
aborted takeoff. The heat from the brakes soak into the tires and cause
various problems.

See:
http://www.maxwell.af.mil/msd/pubs/maxins/32-2004.pdf

Note 4.3.4, time to tire failure after emergency braking operation is about
12 to 15 minutes.

Mark Browne

Mark Browne wrote:


The brakes *will* stop the plane at V1. Other than that, there may be
problems. The company I work for sells parts for "retriever kits." They use
these kits to recover aircraft after they deploy the brakes during an
aborted takeoff. The heat from the brakes soak into the tires and cause
various problems.


For you and Steve, please go back and read where I posted"

Many aircraft tire failures are due to overheated brakes, heating the
wheels to the point of causing the tires to blow out or burn, not from
heat generated by the tires themselves.

That was in reponse to a post that claimed the wheels would provide
sufficient heat sinking to cool the tires.

As an ATP and former airline captain I am very familiar with aircraft
braking limitations.

Rick

On Tue, 04 Nov 2003 05:18:29 GMT, Rick wrote:

Mark Browne wrote:


The brakes *will* stop the plane at V1. Other than that, there may be
problems. The company I work for sells parts for "retriever kits." They use
these kits to recover aircraft after they deploy the brakes during an
aborted takeoff. The heat from the brakes soak into the tires and cause
various problems.


For you and Steve, please go back and read where I posted"

Many aircraft tire failures are due to overheated brakes, heating the
wheels to the point of causing the tires to blow out or burn, not from
heat generated by the tires themselves.

That was in reponse to a post that claimed the wheels would provide
sufficient heat sinking to cool the tires.

Yes, I saw that and agree that when airliner brakes are used excessively
they can cause tire blowouts. But again, the braking requirements and
capabilities and the heating of the tires of an airliner vs. a race car
couldn't be more different. To suggest that because airliner tire
failures due to the brakes generating too much heat mean that race cars
also can't dissapate their braking heat fast enough to prevent tire
problems is a non sequitur.

As an ATP and former airline captain I am very familiar with aircraft
braking limitations.

I'm surprised then to hear you say that thrust reversers provide little
braking at high speeds when in reality, they provide most of their
braking at high speeds and much less at low speeds. That's why, when an
airliner lands, they'll use the thrust reversers first, while the plane
is going fast. Then once it slows down sufficiently, they'll use more
of the brakes.

Steve