Are wheel brakes on most commercial jet airliners capable of holding the jet stationary on a dry surface, if all the engines are given full thrust? Could doing this be potentially unsafe or damaging to any of the aircrafts other structures, such as pylons, wings, etc.
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$\begingroup$ All vehicles usually have at least one braking system that exceeds engine HP, usually by least several times. Otherwise the braking effect wouldn't be effective and in some cases useless. This is a general rule that applies to anything that is braked. $\endgroup$– jCiscoNov 13, 2015 at 10:43
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Yes they are. In fact this is required for a static takeoff. A static take-off means setting the brakes and running up the engines to takeoff power then when ready they release the brakes and start the takeoff roll.
Besides that one of the test Airliners have to withstand is a worst-case V1 abort.
This means starting a takeoff and at the last second slam the brakes, come to a stop and then taxi around for 5 minutes. This all needs to happen fully-loaded and with worn brakes that are still certified safe to use.
Between hitting the brakes and coming to a stop the engines will not have time to spool down and stop providing takeoff power.
Airliner mechanics also do engine run-up tests essentially powering up the engine and going through the power range and making sure it works as specified. This is usually 1 engine at a time.
In these run-up tests loose debris (including cars) can be thrown around by the engine blast. So it's important to keep the area clear.
answered May 3, 2015 at 1:45
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4$\begingroup$ Not if its icy though. Wintertime in the emb145 during crossbleed starts or ice tests we would slide. $\endgroup$– caseyMay 3, 2015 at 2:42
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3$\begingroup$ @casey the question did specify a dry surface. $\endgroup$ May 3, 2015 at 2:48
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2$\begingroup$ For your last paragraph it might be good to mention some layman-friendly demonstrations of the power of jet blast, like the Mythbusters "Jet Taxi" experiment, youtube.com/watch?v=CpX1riSTeJc, and the Jackass 3D jet engine bit, youtube.com/watch?v=Ui3KoDIhnSA (NSFW for a few bits of language but visually pretty clean unlike most of the rest of the movie). Both bits are good illustrations of both a static engine runup with brakes in place, and the awesome power behind a jet engine. $\endgroup$– KeithSMay 4, 2015 at 18:32
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2$\begingroup$ Note that when holding stationary, the brakes only have to withstand the force of the engine, but they do not dissipate any power. The brakes could hold stationary any duration without wear and without heating up. This is very different from braking at speed. $\endgroup$– boglNov 7, 2016 at 14:50
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1$\begingroup$ Mythbusters 'Jet Taxi' link in Keith's comment seems to be dead now, but here's a working one. $\endgroup$– reirabJan 12, 2017 at 7:56