I was supposed to be in a US Army training film once. It was to be on refueling tanks from the air: a tanker would drop a hose to the ground, and the tanks would be refueled as the plane circled above -- picture a cone standing on its point.

I wasn't among those who went out to try this, but the film was never made. Seems like they dumped a couple hundred gallons of gasoline (petrol) all over the Wisconsin woods, so the Army dumped not only the film but the whole idea.

I found out later that the Army also tried the aerial refueling idea by dumping fuel bladders off the rear loading ramp of a C-130. Picture a large water ballon dropped from a couple hundred feet up and you get the picture about why this, too, wasn't a Good Idea.