hangar icing

How to keep the Cessna 170 flying and airworthy.

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N2625U
Posts: 187
Joined: Mon Jul 07, 2008 2:21 pm

hangar icing

Post by N2625U »

A few weeks ago we had the January thaw so a good time to change oil in the plane. Flew for an hour or so warming it up landed and pulled cowling and drained the oil. Warm day good for checking everything out. Let it drain overnight the next day it was warm again but so humid condensation was dripping off the wings and overhead rafters in the hangar. Got the new oil in & filter on, pulled it out of the hangar fired it up found no leaks, drips, runs or errors. So foggy I couldn’t see the runway a hundred yards away so back into the hangar she goes and put the cowling back on. That night the temp dropped into the single digits and the next day it didn’t warm up much from that but was a clear day. To the airport I go opened the small hangar door (unheated hangar with no insulation) seeing some icicles hanging from the plane with frozen spots of water on the floor under the overhead beams the size of dinner plates. Tried moving some control surfaces and they were frozen! Same with the elevator trim. Figured that was a no fly day. A few days later it warmed up enough melted the ice and dried out then checked it out thoroughly and went up to share the airspace with seagulls and crows. Our resident red tailed hawk remained in his tree…
Keep your speed up, Blackhawk on final behind you.
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cessna170bdriver
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Re: hangar icing

Post by cessna170bdriver »

A friend of mine with an as-yet unheated hangar runs a vent fan when the OAT warms up and it seems to keep the condensation down fairly well.

I haven’t opened the big door in about 2 months (98C has been in Mena for some touchup work) but I keep it about 50F inside, so condensation hasn’t been a problem.
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Miles

“I envy no man that knows more than myself, but pity them that know less.”
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GAHorn
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Re: hangar icing

Post by GAHorn »

One BIG difference will likely be whether or not the hangar is insulated. The vapor-barrier of most insulation will prevent condensation.

Down here in (relatively) warm Texas... my friends told me I was silly to insulate my hangar since it was neither heated nor air-conditioned. But I was convinced that the hot sun bearing down on a metal hangar wall/roof would radiate that heat into the interior, and I was correct... local hangars whose owners thought they were saving money and I made same-day comparisons and the difference was very noticeable.

Now that I've added an overhead heater to my hangar I am glad to have insulated it. Last night the temp got down to 28F and the heater easily kept the inside at the selected 58F by running the heater about 50% cycle.

My hangar is 50 X 50 X 18 eaves with ridge-vents at 20' height. Although the manual says the Mr Heater "Big Maxx" MHU80 will heat a 2,000 sq ft garage... it seems to have no trouble at all keeping it comfortable inside the much larger hangar. (2500 sq ft plus high roofline.) It was converted to LP/propane with the included kit so it runs a little less efficient according to the manual, but it's such an improvement! (The unit is rated at 80K BTUs InPut which equates to about 67K BTU output on NG and about 61K Output on LP.) It runs surprisingly quiet and gently blows warm air across my hangar from one corner toward the opposite. It's mounted 10' above the floor.
I can actually WORK out there now in cold wx. It got down to 12F two weeks ago and that, in conjunction with Northern Tool's sale of this unit for $469 convinced me.
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I realize someone is going to be curious about why the 2" sq. tubing is patched together like that... It's because the idiot who had never built a hangar previously positioned the C-purlin/girts on the first wall constructed (the east wall) open-side-up thinking it was better for storage...but the professionals who volunteered to help their idiot-buddy finish the job educated m...errrr... the idiot and convinced m...errr., him...to install the other 3 sides of the hangar with the girts open-side-down...(simpler/stronger/easier to keep clean and makes for better use as shelving)...which means the corner where they meet.... one wall has girts facing up and the other facing down...which required the square tubing to be staggered to allow the heater to be level. I know....TMI. :?
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
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