The A2A Simulations Community

Noticed that at higher altitude, the available brake pressure (when brake applied to left and right) gets lesser the higher one goes. This means one gets less braking ability at higher airport?

I am just guessing,but i supose this has to do with thinner air at higher altitudes,the same reason why your indicated airspeed varies from true airspeed.I guess the Pitot tube and any manomether have the same air density problem.And since it is a pneumatic and not hydraulic system,it is being topped off using external thinner air.But i think this really isn't a problem since you wouldn't be needing your brakes at 15000 and you shouldn't have that significant drop at lower altitudes.

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Владимир Левков/Vladimir Levkov

Aviation is proof that,given the will,we have the capacity to achieve the impossible

Indeed my thought too that the low hydro brake value is due to the thin air. But that being the case, it would also mean weaker braking power, meaning extra landing roll is going to be needed at higher altitude.

Dûh

Sorry, could not resist with that one

Yeah it would mean less braking power.

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Lukas

At higher altitude, if the pneumatics are supplied by an air cylinder, then the pressure relative to ambient would actually be greater so better braking would be expected.
However, if supplied by pumping from the surrounds, I dunno what the result would be.
The fluids popup makes it look like a cylinder filled on the ground.

The pneumatic system uses an engine driven pump, which I would assume draws air from the outside air. I woudn't have thought that the pump would automatically increase its output to compensate for thinner air density. Therefore, I think we can assume that as the air gets thinner, pneumatic pressure output from the pump is reduced.

Regards
Matt

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- G.K. Chesterton.

i7 2600K, 8GB Vengeance RAM, Asus P67, GTX 580.

It shouldnt reall effect it that much.

In trucks and lorries, In normal operation once the maximum pneumatic pressure is reached a relief vave blows off and will continue to until the system has demand placed on it.
I imagine this would be the same in the Spitfire, so at higher alt the maximum pressure should still be reached if no demand is placed on it.
It will however take longer to fill up from nothing with less ambiant air pressure, however this length of time can be reduced by higher engine RPM.

In other words, if your sat at an airport with no demand being placed on the pneumatic system then the airpressue should the be the same at any alt.

I guess there's some clarification needed here ... so is it prior cylinder-filled on ground?

Give it a try -- at high altitude, squeeze the brake and you can see the pressure is way much lower than when on low ground.

So the question is:
is it simulated correctly?