You may want to supply us with a few more details on what you are wanting to do. As mentioned attaching anything to a plane that fires anything is not a good plan at all. The AMA frowns on it, and since 9/11, there are a lot of other law enforcement agencies that might be interested in what you are doing and why. If you are refering to shooting at an RC plane with a paint ball gun, do a search here on RCU as that has been done.  Good Luck, Dave