I built an old Pilot kit of a 42" Mustang. Converted it to electric and put in a 15 sized Astro geared cobalt. Have a 12 cell Nicads pack in it but have never tried flying it. I used Electricalc program to set it up and got it to come in at the original wet weight of 43/4 lbs. I would like to drop as much weight as possible and try to keep a duration time of 10 -12 minutes if possible. I appreciate any help as my brain trust hit full with Nimh info and I can not cram any more battery theory in. RobertV