"David Lesher" wrote in message
...
"Dave Stadt" writes:


That's not exactly what could happen in a brake circuit. We are talking
brake circuits not crankcase. Leave oil exposed to the atmosphere and it
does not absorb air.

Nope, just water..... but in any case the key issue is having a
fluid that has very low compressibility even at high temperatures.
(Look at the NOVA series on the 777; the rejected-takeoff test has
the solid carbon rotors glowiing bright orange as the rims melt...now
THAT'S hot....). Even a small amount of suspended air makes it
compressable. And oil, unlike brake fluid, does not err ?stratify?
well.

Automotive brake fluid was, ISTM, the very first federal
automotive safety standard. It must have:

Traditional automotive brake fluid is alcohol based and is hydroscopic. A
can will become useless in a matter of hours if not tightly capped. It is
not oil based.

Ahem.. it's not alcohol-based; it's glycol based. (Except DOT-5 which is
silicon..)

Ahem..glycol is.....well why don't you look it up.