Marc Auslander wrote in
:

Common knowledge is that we should top up our fuel tank for the winter
sleep. Argument is that otherwise the temp changes will continuously
condense water into the tank, as moist air is pulled in, condensed,
and then expelled.

I have no doubt that the effect is real, but wonder how big it
actually is. How much water per gallon (or liter) of air would
condense in one cycle of some plausible temperature range and some
plausible outside dew point?

(I think I know how to calculate this, but wonder if its already been
done?)


You can't calculate it because you can't calculate the humidity of the air
from hour to hour, an immense variable.

It doesn't matter how much....it happens. EVERY airplane at the airport
hangar has tanks filled to the lip because of it. Water in their fuel
spells disaster.