Ok, I've come across a Nexstar Plane, it was damaged at one time or another. Question It came with 4) 9.6 volt NiMH batteries( they were no good) the ESC runs two in series, will the Plane still fly ok if I just run it off (one) 4s 3200 or 4500 Mah battery. As I noted these two 9.6 volt batteries were run in series for a total of 19.2 volts.

Also, it came with rimfire 32 plus 11 x5, 11 x7E props & I have on hand a 12 x 6 prop. NOTE: the ESC is wired to run two NiMH packs in SERIES,
I just want to make sure that a( 4s 4500) Mah alone will get this plane off the ground with no problem...

Hi Sidney, the 4S pack will probably get it off the ground just fine. A 5S pack would get you closer to the voltage that the plane was originally designed to fly on, but the LiPo pack should way significantly less. With either a 4S or 5S LiPo replacing the two NiMH packs, you'll want to double check you center of gravity closely to make sure the plane isn't tail heavy before trying to fly it. Good luck and good flying!