On Mon, 2 Oct 1995, Joel Walker wrote:

> - private aviation:
>     what the heck do small two and four-place aircraft do for heat? cause
>     it is gonna get really cold at 10,000 feet! and their engines aren't
>     really any bigger than ours. (admittedly, their interior volume ... to
>     be heated ... is much smaller).
> 
> anybody got any other ideas? small, not-necessarily-mobile, places of
> habitation that need heating for their human (or animal!?) occupants??
> 
> surely somewhere, somebody has solved this problem ... cheaply.
> 
> joel
> 

As soon as I saw this I called my little brother to find out just how
his airplane heater works.  He's got a '67 Alon AirCoupe, two place, 4-cyl.
1st we don't usually fly at 10,000 feet, but yes, go up on a fall or 
winter night, even here in Florida, and the outside air temp. at 3,000 -
4,000 feet may well be around 35F plus the fact that your doing 100mph
and the AirCoupe is NOT airtight.

Actually the airplane has two heating systems, one for the carburetor (to 
keep ice out) and the other for the cockpit (to give occupants idea that 
they have heat).  I believe the former is more effective.  

When you  turn on cabin heat, a fresh air tube is opened, this tube coils 
through a box that surrounds an exhaust manifold (temps reaching 600F, i 
think). Inside the box the air in the tube is heated and passed on into 
the cabin.  At best it takes the chill off.

Then again airplanes don't usually have to worry about heat at rest.

Trace Choulat
tchoul@unf6.cis.unf.edu