it should be fine, cycle it to be sure. i wouldnt bother with trickle charge but that is just me, no reason to fry a battery when its already fully charged.
if your that worried about it buy another one for your expensive plane and use the fried one for a inexpensive one.
all-battery.com has some good batteries
http://www.all-battery.com/6v2000mah...ctor11106.aspx
for 9 bucks + shipping i would buy a few of them anyways.