Read this book years back about several men who were contract oil rig workers (Vietnam, but not sure)overseas- they get attacked and are approached by CIA to get payback and are recruited as assassins. Upon returning to US, one wants out and has to kill of his superiors as they won't leave him alone- he asks to meet them in motel and flies remote controlled plane w/bomb into their room- Help! Its driving me mad trying to think of this! I do remember it was paperback and on the cover it had a forearm holding a small machine gun