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Hi Bob,

Chemistry was not my big point in studies, so I have no doubt that you are correct But, all the literature I have read on the two different formulas for aircraft brake fluid appears to make a point that the fluid with the higher flash point requires more energy (heat?) to ignite it. Less prone to ignition? In fact, the military is the one who specified the new brake fluid with a higher flash point due to the combination of military operations and downside of a flammable brake/hydraulic fluid.

So am I wrong in assuming that a fluid with twice is high a flash point as a similar fluid requires more heat to ignite it??

Ed A

----- Original Message -----

From: Bob Darrah

To: Rotary motors in aircraft

Sent: Thursday, December 01, 2005 10:46 PM

Subject: [FlyRotary] Brake fluid flash point

Ed,

Me thinks that maybe you have a misunderstanding of the term "flash point". It is not what most people assume it is. I say this because the flash point of the gas in your tank is something like 60 degrees BELOW 0. That means that on a hot day, the temperature could exceed the flash point by 160 degrees and you don't see too many people concerned about that.

Bob Darrah

----- Original Message -----

From: Ed Anderson

To: Rotary motors in aircraft

Sent: Thursday, December 01, 2005 7:43 PM

Subject: [FlyRotary] Re: fuel/brake lines

Rusty,

I went with the new high flash point aircraft brake fluid (MIL-H-83282)- flash point is 450F vs 240F for the old stuff. I had to get a gallon of the stuff (enough to probably last me for years and years and years), but after the fire, I feel a bit more comfortable that it won't go up with the temp a little over the boiling point of water. I considered some of the auto brake fluids - but have heard some horror stories about incompatibility with aircraft seals - I know there is some DOT formulas that supposedly are compatible - but did not feel like experimenting {:>)

Ed