I've used Red Dragons and several other types of combustion heaters over the years.
If electricity is available, don't even think about it. There is a device that couples to a cell phone that will turn on the electricity to a device remotely, but a phone call. A couple hours before flight time, call the "by the minute" cell phone ($10 at Walmart), and it turns on the heater. Someone on this forum gave specs for such a setup earlier.
The Red Dragon works okay, but there are a couple of issues:
1) You have to monitor them pretty closely. That does NOT include doing a thorough pre-flight while its' running, in my opinion. It means you WATCH it. If they go up, they go enthusiastically, and you need to be quick about shutting it off. Not very likely, but only takes one...
2) Let's say the temp is 20 above. You put the Dragon on the engine for 20 minutes. Now, what you REALLY need to do is to cover the engine with an ENGINE COVER (read NOT a sleeping bag, or??) to seal it up and let that entire engine normalize in temperature. The idea is to heat for a while, then shut off the heater with the engine covered tightly, do your preflight THEN, and after another 20 minutes or so, the engine parts and oil should all be about the same temperature. Go fly. The key is NOT to do quick pre-heats with these things, but to heat, then allow the engine temperatures to normalize.
3) Propane makes a LOT of moisture. All that moisture is going to reside in your engine compartment. That's not a huge deal, but just be aware that things will be dripping after a preheat with a Dragon.
4) Finally, it's just a lot of stuff to lug around, or store.
They work fine, just take your time.
BUT, if I had electric service, I'd get a cell phone setup as previously described, and turn on the Tanis or REiff system remotely.
MTV
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