Solar exhaust fan

[moparrob66]

I just closed on a 172 and it will have to be tied down here in SW Idaho. I'd like to keep it cool inside and I'll use reflective window shades when its parked, but does anyone use a solar exhaust fan to circulate air or is that a trivial pursuit? As a kid, my grandpa was fond of the JC Whitney catalog and ordered all kinds of questionable doodads from there, and one of them was a solar exhaust fan that seemed to work. If you walked past the car window while it was running, hotter than ambient-feeling air came out of the fan.

I also got to thinking about the reflective shades inside the window...would that reflect heat back onto the plastic windows and make the plastic hotter than if there were no shade in place? I dont want to roast my "glass" to save the upholstery.

 

[GeorgeC]

I used the reflective shades until my real cover from https://aircraftcovers.com/ arrived. I can't praise them enough. I had to send mine back for repairs and alterations once, and they made it easy. I recently washed and re-waterproofed mine, still looks new after five years outside.

Recirculating hot air inside the cabin won't do much. It doesn't get *that* hot anyway, since the cover largely prevents the greenhouse effect from happening in the first place.

I dunno about the 172, but water drips in through the piano hinges on my cowling; I should have gotten an engine cover, too.

I also don't have my wheel pants installed, and I have wondered if putting waterproof drawstring bags over the wheels would keep moisture off the guide pins and rotors and prevent rust... or trap moisture inside and promote rust.

 

[JOhnH]

I don't know if it's true, but I have heard that those shiny reflective shades cause the plexiglass to get too hot and causes problems. I have no details, but I'd look into it if I were going to be doing this on a regular basis.

 

[moparrob66]

I wouldnt just recirculate hot interior air, I'd want to blow it out. I'm imagining ducts that i could slip over the wing root vents that would either blow hot air out or draw it in. Maybe the juice aint worth the squeeze?

 

[moparrob66]

Do the exterior covers wiggle around in the wind and chafe the paint?

 

[GeorgeC]

I wouldnt just recirculate hot interior air, I'd want to blow it out. I'm imagining ducts that i could slip over the wing root vents that would either blow hot air out or draw it in. Maybe the juice aint worth the squeeze?

Doesn't sound worth it to me. Plus, it's not a bad idea to cover the vents from the outside. Had I done that, maybe I would not have had a mud dauber nest on the inside...

Do the exterior covers wiggle around in the wind and chafe the paint?

That hasn't been my experience.

 

[Lndwarrior]

I wouldnt just recirculate hot interior air, I'd want to blow it out. I'm imagining ducts that i could slip over the wing root vents that would either blow hot air out or draw it in. Maybe the juice aint worth the squeeze?

If you could jury rig a flex duct connected to one of the vents this could reduce cabin temps on hot days. A solar fan is low wattage so the motor won't add much heat. If you could get a fan that exhausted 5 or 6 air changes I think it would make a difference. The result would be to reduce the cabin heat to whatever the outside air temperature is. The cabin temps can be 10 to 20 degrees above the outside air temp. Or more depending on the outside air and ramp conditions (reflected heat radiation).
Duct the fan to one vent. Leave the other vent open to draw in outside air.

For the minimal cost involved I think this idea has value.