I saw a show this weekend on the Son Tay raid to rescue POW's in Vietnam.  It was really a pretty good show.   One thing stood out as just jaw-dropping.

When they were planning the raid, they realized that Huey's were not fast enough.  Their solution was to fly directly behind the wing of a C-130, and I mean directly!  They would get the choppers so close that the main rotor blades were over the wings of the plane, and they would draft off of the 130, like a race car.  What kind of balls does that take?  I mean, jeez!  They could fly longer and faster like that.
They wound up scrapping the hueys because they were too cramped.  Still, I thought that was pretty damn cool.

Didn't they end up using CH-53's? Better suited for their purpose, even the "A" models.