What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

That time of year: improving cabin heat

Dugaru

Well Known Member
I've had some modest success improving the cabin warmth of my RV-9A, and I owe it all to the various posts here. So I thought I would list what I've done, in the hope that some other freezing RVer might find this info useful in the future.

1. Sealed up the eyeball vents. I was getting a ton of wind through my plastic eyeball vents, even when they were "closed." Two vinyl caps, suggested by someone here on the forums, were a quick solution and a huge win in the "bang for the buck" category:

https://www.amazon.com/gp/product/B075WWJP7N/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1

I'm sure someday I'll bite the bullet and get decent aluminum eyeball vents, but for now, these worked wonders.

2. Wrapped the exhaust muff. I got some exhaust wrap from the aviation department of Autozone and wrapped it around my heat muff. My hangar neighbor A&P signed off on this approach, while cautioning that it's important not to wrap the actual exhaust pipes. I also stuffed a copper scouring pad into the muff to give the air some more hot metal to flow around before entering the cabin (another suggestion I picked up here). The improvement from these changes was noticeable.

3. Heated clothing. There's a lot to be said for solving this problem with clothing, since it's bound to be cold getting in and out of the airplane as well.

I got a battery-heated vest for my intrepid copilot, and she raved about it so much that I got one as well. This is one of those rare "yeah right" gadgets that actually turns out to be super useful in real life:

https://www.ventureheat.com/130-heated-puffer-vest-for-men.html

Prices appear to have gone up since I got ours, so you may want to hunt for an equivalent by another brand. I'm guessing there's all sorts of heated clothing pitched at motorcycle folks.

4. Hideous hat. The reason Elmer Fudd wears an Elmer Fudd hat is because those things are..... AWESOME.

https://www.duluthtrading.com/mens-...MIm7zT3M_h4AIVRFqGCh3UQAOdEAQYASABEgJVXPD_BwE

I use in-ear Halos for my headset, so I can fold down the ear flaps on a Fudd hat and be super comfy while flying. The long bill on this one is a big plus under an RV canopy, especially because you'll likely be stowing the overhead shade in order to soak up sun.

I got a 2XL and amazingly it was just on the verge of being too large (my head is so huge, I don't have a forehead, I have an eighthead....)

Key thing to keep in mind: nobody can see your fashion up there. Just remember to take the Fudd hat off before landing or crashing, so that you aren't caught alive or dead wearing it.

My next projects:

1. Tackling the gale blowing up from the stick well.

2. Sealing the rear of the canopy. I'm still getting a bracing little breeze hitting the back of my head. Starting to think about how I can do this cheaply and easily, and in a way that might be removable during the summer, when having the breeze might be nice.
 
My next projects:

1. Tackling the gale blowing up from the stick well.

2. Sealing the rear of the canopy. I'm still getting a bracing little breeze hitting the back of my head. Starting to think about how I can do this cheaply and easily, and in a way that might be removable during the summer, when having the breeze might be nice.

1. Seal the aileron tubes with something like a sleeve from a wind-breaker jacket.

2. If your -9A is a slider, then you want to stop the air from going OUT by your elbow. That is what draws the air in from the back.
 
Last edited:
"8 head" - now thats funny!

Thanks for the suggestions. I was thinking about going with heated seat pads - 12v cigarette lighter style, so I put two of those receptacles in my plane (one for each seat) and a 15a breaker.....hadnt even thought about heated (motorcycle) clothing, but thats a great idea. Probably too late for you, but I have a slider vent in the tail of my canopy, cheap bowden cable operated. Plagiarized the idea from another owner....lol
 
You can reduce the heater flow by adding a restrictor to about 1" dia. at the firewall baffle.

Use the search function and find some posts by Alex Peterson, he had a comprehensive list of improvements. Make your search range back 10 yr ago.
 
My next projects:

1. Tackling the gale blowing up from the stick well.

2. Sealing the rear of the canopy. I'm still getting a bracing little breeze hitting the back of my head. Starting to think about how I can do this cheaply and easily, and in a way that might be removable during the summer, when having the breeze might be nice.

These two will have the biggest influence on improving your heater performance.

If much cold air is coming in, it will overwhelm even the best performing heat muff.
 
My next projects:

1. Tackling the gale blowing up from the stick well.

2. Sealing the rear of the canopy. I'm still getting a bracing little breeze hitting the back of my head. Starting to think about how I can do this cheaply and easily, and in a way that might be removable during the summer, when having the breeze might be nice.

1. For sealing around the aileron push tubes, I followed an idea I either saw here or on a builder's website which worked very well. I bought a tyvek paint suit and cut off a portion of each sleeve. Disconnected the push tube, slipped the sleeve over the push tube, reconnected the push tube to the stick, tie-wrapped one end of the sleeve to the push tube, made an aluminum ring to match the opening in the lower fuselage for the push tube, and secured the sleeve between ring and the fuselage wall with screws. Make sure the sleeve is long enough so it will flex left and right as the stick moves.

2. For the back of the canopy on my slider, I've tried a couple of thin weatherstripping products that worked well on the curving sides of the fuselage. One had a kind of D profile with self-stick tape which is attached to the fuselage that reduces the backdraft quite a bit. I haven't solved the draft from the doghouse area, yet.

Overall, those mods warmed it up quite a bit, just using one heat muff, especially with no more cold draft between my legs.
 
I installed a seat bottom and seat back heater in my RV3. I bought the set from Flyboy Accessories. I can?t believe how well it works. It has a two position switch and I find myself switching to the low setting by the time I?m finished with my run up.

I noticed today that I still have a fair bit of air leaking around the stick boot. I?ll probably solve that with some foam and a zip tie.

I also have a pretty decent sized gap on the aft end of my slider canopy. I?ll probably solve this with some weather channel from the Home Depot aviation aisle. I?ll probably remove it in the summer because airflow is welcome in warm temps.
 
These are all solutions that incrementally help but the better solution would be recirculating heat fed with a centrifugal blower, like your car, with the ability to mix in some fresh air to keep humidity in check. Also heat muffs used on RVs are generally too small to work effectively. I fly a Beech Musketeer occasionally and it has plenty of heat at -10F. It has a large heat exchanger.
 
These are all solutions that incrementally help but the better solution would be recirculating heat fed with a centrifugal blower, like your car, with the ability to mix in some fresh air to keep humidity in check. Also heat muffs used on RVs are generally too small to work effectively. I fly a Beech Musketeer occasionally and it has plenty of heat at -10F. It has a large heat exchanger.

If my cowling was the size of a Beech Musketeer cowling, I?d probably have room for a larger heat muff and a more extensive air recirculation system.

It?s kinda like saying ?If I was taller, I wouldn?t be so overweight.?

:D
 
The Heat is on...

My next projects:

1. Tackling the gale blowing up from the stick well.

2. Sealing the rear of the canopy. I'm still getting a bracing little breeze hitting the back of my head. Starting to think about how I can do this cheaply and easily, and in a way that might be removable during the summer, when having the breeze might be nice.

Dug,
All great ideas above.
RE above: For the stick well gale put silicone around any wing root leaks including fuel line holes. Find an auto upholsterer to make you a set of stick well boots using a gear shift lever boot as a guide or order standard ones from Amazon. Search MTC Shifter Boot.

For the rear canopy find the leak and mark area with a sharpie, buy some felt at Home Depot and contact cement it under the canopy skirt one thin layer at a time till it seals.
Trial and error and patience will pay off.

Additionally, I flew my T-Craft with minimal cabin heat and my RV4 all winter with no cabin heat down to minus OAT temps in South Dakota.
My stay warm techniques included (as others mentioned) A Carhart work suit and "Commisar" hat in my T-Craft. I added a bed spring inside my T-Craft heat muff and used 3M lightweight alum duct tape for air leaks in both airplanes and cheap (like me) seat heaters in my RV4.

https://www.amazon.com/Russian-Sovi...ocphy=9027240&hvtargid=pla-579462963733&psc=1
шляпа комиссара

https://www.walmart.com/ip/Car-Heat...0735&wl11=online&wl12=331471151&wl13=&veh=sem
The Hot seat

A cold butt isn't cool...:)
V/R
Smokey

PS: I once nursed my RV4 to 20,000' wearing the same suit and hat with seat heaters cooking and was comfy until the descent where I actually started sweating. My RV3 hangar mate wore a fully heated motorcycle suit all winter with no heater and stayed toasty.

 
Last edited:
A cold butt isn't cool...:)
V/R
Smokey

One thing you can be sure of with a nice drafty cockpit....youre not gonna die of carbon monoxide poisoning.......and you'll never have any fogged up inside windows.

Sometimes, its good to leave things well enough alone.

Just a thought.
 
Back
Top