It has had some small grass crashes nothing that really hurt it much.But it is possible.This plane is very tuff and crashing it in the grass going 10 Mph shouldnt do much i would think.The batteries are brand new and the exact same thing happens with the stock battery.Its the stock Prop also,no mods have been this to this plane at all.I still havent cut it open because i know little about this stuff as im still new to the hobby.I need to hook up with one of the old schoolers at the park this weekend and see if he has a voltmeter to help out.I hate waiting days and days to see someone who may not even know what the problem is.I hope that if the esc or the motor is broke that they are cheep and easy to replace.I will buy the replacement stuff from Hobbycity if i have too as thats the cheepest place i know of so far.