Still fiddling with the Cessna. I am quite happy that the battery seems to be behaving. We have a charger which has some intelligence and does a good job of charging and conditioning. Airplane batteries are expensive, about $250. I have a sealed Absorptive Glass Mat (AGM) which beats heck out of the conventional lead acid batteries which always managed to leak acid and destroy battery boxes. The reason they are so expensive is that they are "certified". That means expensive in any language.