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bobnoffs

Well Known Member
anyone know the rating differences between blue and red sleeve? acs is very descript about the red but not the blue.
thanks
 
Interesting reading

is available at the following link:http://www.wmtonline.eu/fileadmin/Downloads/FIRERESISTANCE.pdf

Mostly, it seems, the 5 minute and 15 minute ratings apply to hose/tubing with fluid running through it. Fire sleeve does not keep heat from getting to whatever it protects, it just increases the time that the protected article will continue to function. Fire sleeve does not "fire proof" anything, it just limits the rate of heat gain to allow longer function without failure.
 
My $.02 worth---"Firesleeve" is probably a misconceived name. Heat sleeve is probably more proper. Lets face it---if you have an inflight under cowling fire, WITH FLAMES, then the blow torch effect of the air passing through the cowling---OR what might have been the cowling, is probably enough to destroy whatever lines you have, no matter what precautions you take.
BUT---effectively insulating the hoses and fluid medium from heat is a major help in reducing the possibility of fire. And---if you can keep the hose intact, the the fluids won't get on a hot exhaust, and that helps the situation.

"Fire-proof" hose assemblies, as defined by the FAA, must withstand a direct flame for 15 minutes under specific flow conditions without failure. Fire-resistant lines must withstand a 5 minute exposure under these conditions." Again---I think "fire proof" is not the 'right' term for this.

WE know of a fuel hose (with firesleeve) that was resting ON the exhaust for +-150 hours of flight time with no damage, over than some abrasion and discoloration. (VAF member with ALOT of posts.) We surmised that without the sleeve, the teflon hose liner would have been damaged, and most probably created a fuel leak that would have been catastrophic.

I personally have NOT seen the aftermath of fire on engine hoses after catastrophic inflight fires, nor do I want to. The norm is to "firesleeve" hoses firewall forward that carry fluids, and thats what we do.
Tom
 
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Bob----we know that there are different grades of silicone RTV that is used, so I'd venture to say that there are different temperature ratings of "fire sleeve" .
Red RTV is rated at 650*, and blue is generally 500*. But---I'd defer to the manufacturer of the 'fire sleeve' for their rating.
Tom
 
Are we to fire sleeve the oil lines to the cooler? there are none on the lines from vans?
 
Bret - when I had mine made by Tom's business partner, Steve, at Aircraft Specialties, he insisted on the oil cooler lines being sleeved. In retrospect, I'm very glad he did. Just think, they are full of oil, and often run very near the engine-driven fuel pump and its associated fuel lines. That's a whole lot of combustibles in a small area. Sleeving the oil cooler lines is cheep insurance.
 
Bret we do. Vans doesnt unless its really close to exhaust, like the RV14. Generally because the coolers are away from the exhaust, you 'could' delete the sleeve. My theory is that we need to protect the teflon liner from excessive heat, so we sleeve the hoses. (Picture a teflon tube with .040 wall. Get it 'warm', and it will begin to distort, and could possibly leak under pressure.)

Tom
 
tom,
i was under the impression firesleeve only delays the intense heat to the line giving the pilot a chance to change the situation. firesleeving a line to protect a line from a muffler doesn't seem to be a solution . pretty soon the temp inside the firesleeve would be the same as outside. the liquid in the line would have some effect lowering the temp but then a better ''r'' value insulation would be more effective for that wouldn't it? just a little confused about the purpose of firesleeve now.
 
Bob---obviously fluid getting on a hot exhaust is a bad deal. So---Yes, firesleeving does insulate the hose, and with that 'probably' does lower the fluid temperature. I say 'probably" because we havent put probes in to measure the temps.
I do know for sure the the hose I mentioned in a previous post on a well known VAF member----if he wants to comment here thats cool--would have failed and a probable fire would have happened. In Flight or otherwise, but I'm certain that the combination of firesleeve and teflon hose kept a disaster from happening.

Whether guys want to use firesleeving is their choice, since they are the manufacturer of their planes. We make recommendations based on experience, and generally accepted standards. In the building process, if routing a hose close to a muffler, or exhaust close to the cylinders is necessary, I'd sleeve them, AND add heat shields to protect the hose. If at all possible, I'd re-route to help the situation.
Lets face it, in a fire, having firesleeve or not may be a moot point. But, if it delays exposure of the hose, and its fluids, then its worth it to me.


Tom
 
Been on soap box for a while

concerning fire sleeve. I am thrilled that the word is getting out. Tom is exactly right.
Our incident came so very close to disaster that I obsess about it, I suppose. It is a detail that is often overlooked, easy to miss and very important to safety.
 
Is everyone using steel fittings FWF? I have a lot of aluminum fittings that came with the EFII kit, including the fuel pressure regulator?
 
Bret

I advocate using steel fittings on the hot side of the firewall... everywhere.
I think it is good practice and does not cost much anyway.
 
Bret, again a matter of preference. We try to use steel wherever possible, especially on engines. Exceptions are on -10 and larger hoses (inverted oil, etc). BUT----many OE's use aluminum AN fittings. I advise you to check the aluminum fittings you are using to make sure they are "AN" grade, and not imposter fittings, that may or may not be aircraft grade.
 
Scott---want to share about "Our incident came so very close to disaster that I obsess about it"? Might be something that we can all learn from.
Tom
 
Tom

"our incident" was on a radial engine. New to me aircraft. At that time knew nothing about how it should be plumbed. Someone installed a soft line from the oil cooler to pump, with fire sleeve. It should have been a hard line. On the first flight away from home the heat from the exhaust cooked the soft hose causing an oil leak.
When the oil line finally gave up I was over a field in SoCal. Power back, very fast decent to a downwind and landing. No damage.
Fire sleeve only showed a minor indication of temperature, hose was toast.
Just very fortunate that a fire did not ensue, and a lesson was learned.
 
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