Keeping plane outside / charging battery

[sedatedokc]

After 2 years of a warm hangar, I am now mostly having my DA42 parked outside. Typical daily temperatures over the winter are a little above freezing (1 - 4 degrees C). Of course some days below freezing. Additionally I am flying a less often than I used to. I have the diamond canopy and engine covers and I will be ordering the bruce wing covers.

My primary question is about the battery. Is there any recommendation on how often I should be going to the airport to start the engines to keep the battery from going flat? If I got some very long extention cord (20 meters?) and some kind of APU, I might be able to go to the airport and plug it in while I wait and then pack it up, if that is a superior option. (How long would that kind of charging take?)

Any other long term outdoor storage tips, particularly for cold areas, are welcome. For example, I am not convinced if using concrete-tire tie downs is a good idea or not.

[michael.g.miller]

The battery is cheap, relatively speaking, around $1k plus an hour of labor to replace.

What's not cheap is your engines! If you don't take them for an extended flight at least every week, you risk corrosion. That will be $80k per side for a new engine.

Fly often, and if you're not flying for an extended period of time, pickle your engines or get a partner.

[Mjwatlanta]

I use a small generator from Amazon and a $450 charger from Sportys to load data bases and fiddle with avionics to avoid drainage of battery. If you buy a generator make sure it has enough Amps for the charger. Not that I would make that mistake myself…. I bought a solar trickle charger and got the inputs/connector for the battery, (the plan was to strap it to the wing) but I’ve been flying so much I’ve not tried it out.