Exhaust Heat and On-Board Electronics

[brownj]

Does anyone have an opinion on the possible reduced longevity or premature failures caused by running our exhaust systems (cans / pipes) inside the fuse in close proximity to the on-board electronics. I'm not talking about a hot part coming in contact with wires or components, etc. Just the high heat environment we've created for the electronics by running the exhaust systems enclosed in the fuse.
I've spoken to numerous pilots with this type of installation and have yet to have a problem reported or any negative comments.
Any thoughts out there?

[Jamieman]

As far as i know lots of people know about it and have been concerned about it at one time or another.
Some have heat shielded the pipes, some have added extra cooling vents to the fuse.
I personally haven't had any dealings with in fuse pipes yet so have no first hand experience.
However, most electronic components perform better at cooler temps.

[madmax]

Hiya Mr. Brown! Welcome if I missed ya before!

Interesting question, anyone ever got the inflight ambient temp through Eagletree or similar?

[adrian]

been bothering us all for a while - i make sure that my box is well vented and the mountings isolated - but there is still heat and i am sure it affects regulator performance and the rest??

[The Flyin Hawaiian]

Heat sheilds, and plenty of venting is a must. Myself i try and isolate the electronics by heat sheild and some type of barrier. My new project I will be running ES Composite tuned pipes, and the one thing I know is that Carbon Fiber pipes retain heat instead of dissapating heat. So my goal is to do all three, Heat barrier, isolating, and plenty of venting.

[brownj]

Thanks Max, just shy.
Flyin Hawaiian, good point and solution, just need a mfg. to make CF cans.
I like the idea of shielding also. Unfortunately some plane designs make it pretty difficult to install shielding to isolate the heat. With pipes, I venture to say it may be impossible?
I'm going to speak to Smart Fly at the Ontario show and see what they have to say. If we had some telemetry on the actual in-fuse temperature, that would be important for the manufacturers to know I'll bet.

[Pittsflyboy]

On aluminum cans it is possible to have them ceramic coated and that dose help reduce the heat they emit. Could also coat CF, it just would not look so hi tech.

Tom

[adrian]

now we have heat and weight - two bad enemies for sure - venting is the best solution i think??

[brownj]

OK, here's some info from Robert at Smart Fly.
He indicates the Smart Fly electronics can safely operate in temperatures of 75C, or 167F. I haven't measured the temp inside the fuse with a thermometer, but I'm going to venture to say the temp is no where near 167F unless you have your PD box sitting on top of the headers....NOT
While my instinct tells me this isn't a good situation, I think we're safe. And a little baffeling, shielding, venting seems to be the answer.
Thanks for all your inputs.
Jim,

[Colonel Klank]

	Quote: Originally Posted by adrian
	now we have heat and weight - two bad enemies for sure - venting is the best solution i think??

Not that I have any valid opinions, but I just wanted you to see how ridiculous my plane looks after having 4 engines installed in it. (3W140, Hacker Quad, Evo150, DA150)
It looks like someone used a chainsaw on it and I don't think I will have any heat related issues because of pipes and not enough ventilation!

[pbrantuas]

I know that Ryan Archer doesn't have any shield between his Greeves Pipes and the rest of the plane in his Comp Arf 260. My 3W Yak also has no shield between the canisters and the rest of the plane.
I do have some good vent holes where the exhaust exits, and every time I check the temp on my headers, it is around 150 degrees.
I predict the inside of the plane is around 100 degrees tops.

I will check the temp inside the plane next time I'm out flying.

[alec taylor]

all my planes have the cannisters boxed in so no heat goes near the radio gear. good size air outlets with air dams. also 1 at rear of fuse. alex