"Go" wrote in message
oups.com...
So far my O2 experience has been up to FL180. Certainly going far above
that brings forth other serious considerations. I have thought I would
install a continuous flow system as a back-up to the EDS if, and when I
decide to fly at those altitudes. Then also a spare/emergency?

Do you have any special considerations for the glider primary batteries
when it gets that cold?


I think it depends on how long exposed as well as how cold. The ship's
lead-acid batteries have a fair amount of mass, so internal temperatures
will drop more slowly than some other stuff in the glider. Obviously,
battery location plays a role too, i.e. it's typically warmer in the cockpit
than elsewhere. Since the batteries are discharging and have some internal
resistance, the internal power dissipation also adds warmth. That said,
battery capacity at freezing will be down some 20% or more, and at -22F,
down 50%.

I understand Stemme insulated their battery installation for the wave
flights in S. America several years ago.

bumper
ZZ Minden, NV