[Jim727]

I can't speak with authority about bizjets, but for the bigger jets manufacturers are pretty determined to keep combustibles under control - for obvious reasons. It is possible to get some raw jet fuel overboard through tank vents, but that would most likely happen 1) full tanks, 2) rising temps, 3) takeoff. If the jet is 500' overhead the probability is very high that the small amount that could escape the tank vent would be fully vaporized.

Then, of course, there's "dumping fuel" to lighten the aircraft, but you'd have *no* doubts then.

Jim