On 28 Dec 2004 06:51:30 -0800, wrote:

My EDM700 (Arrow 200) has shown 13.5-13.7 in flight for a couple of
years. It recently dropped to 12.1, which I've interpreted to mean the
4-year old battery is shot. Just replaced the battery but haven't done
test flight yet.


This may be an alternator problem. The output reading is what is
coming off the alternator, not what is being held by the battery.
This happened to me, and I ended up re-building the alternator. The
good news is a re-build is about the same as the cost of a new
battery!

Good Luck.
z