I didn't intend on actually dropping them while there was still fuel in them. Auxilary fuel tank is a better term. I just wanted to see if other people have done it before with success and how to go about it. After Mr. Matt's post it does cause me to think about the saftey issues of an auxilary tank. It could come detached from the model in a high g turn and impact the ground. I'm not sure if it would explode or not, but it sure would be a concern. Maybe if there was a HDPE tank inside the kelvar, that would make it safer.