RE: WHAT IS THIS HOLE???????
DON,T TRY TO FIX IT!!!!!!!!!!!! I had one that did not seat right and when it runs out of batteries or fuel and sets dead for a few minutes IT WILL SINK making it much harder to retrieve and you run the risk of damaging electronics for no reason other than I ran out of gas no cool stories about the crash all ya got is ran out of gas need new reciever just change it it,s worth the five bucks.