Brake temperature lower with harder breaking?
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Hello,
I've had some trouble with my brake temperature. I always overheated the brakes. I tried to use less braking and it made the issue worse. I can use the whole 3km runway with minimal braking and I'm easily creating a raging inferno.
I now tried to brake harder and I noticed that the brake temperature stays much lower. If I come to a stop within a km, the brakes stay nice and cool.
Is this behavior realistic or does the brake temperature simulation only look at the time the brakes are applied and not at the pressure? -
ITRW the carbon brakes start to operate and do their job better as they warm up. Brakes should be used evenly - don’t ride a brake against steering, and don’t ride (drag) brakes with light pressure generally - if you do, temps will quickly rise. Temps should be less than 300C for take-off (200C with the low pressure tyres). It’s regarded as poor airmanship to use light braking simply because of a long runway; don’t try to judge it like that. When landing and the nose wheel is down and spoilers are deployed, start braking and reduce speed smoothly. Nothing more embarrassing and career terminating that coming off the end of the runway at low speed because you’ve misjudged things or you suddenly discover the brakes are not working. After engines have been below flight idle for 2 minutes and APU stable, consider shutting down engines 1 and 4 if there is prolonged taxi to stand.
Select brake fans to AUTO during the after start checks and leave them in that position - even through a turnaround if temps are still warm.
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I have the same issue. Brakes are unrealistically hot after a landing with light to moderate braking application. Even when letting the aircraft roll down a long runway, barely feathering the brake will lead to hot temps.
Perhaps this is something to do with slight spiking in the controller axis? Not sure.
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The question is whether the temps are too high or the brake fans too weak...
Are the brake fans really cooling the brakes at a realistic rate or is there a bug?
I find 25 minute turn-arounds pretty tight in terms of brake temps at higher weights WITH brake fans in AUTO. -
General advice, landing and taxi in, typically achieves 450-550C. Brake fans running on chocks after shutdown and before engine start must be for a minimum of 15 minutes. Typically, if you start up and taxi after a minimum of 20 minutes and can start the takeoff with brake temps at a maximum of 200C, all OK.
There are tables within the aircraft manuals for calculating the required cooling period if brake fans or BTI are unserviceable. In service, on a hot day with a 30 to 40 minutes turnaround after a max weight landing on a 6,000’ runway, the brakes would be usually be found cool enough to start up and taxi out.