RE: ParkZone P-51 Mustang RTF
VR6,
The problem is that the battery (NIMH) is shorter than the battery box. The battery slides up and down gaining enough momentum to knock open the cap. So what I did is out of balsa I made a rectangle peice with the corners knotched out. This allows me to slide it in and push it to one side and it locks into place. Between the balsa peice I put foam to keep the battery from sliding up and down. It is an extra step every time you fly but it looks a lot better in the air!
I will have to take a pic and send it.