Wasn't this movie the first time that two helicopters were able to hover inside a building?? A stunt that's easy to do with computers these days but exceptionally hard to do in real life in fact almost impossible.
shareWell, it looked like a very large hangar and it would have been dangerous. But one of the copters looked small and highly maneuverable, so possibly the director got the safety go-ahead to do the shots?
My votes:http://www.imdb.com/mymovies/list?l=9422378
I remember reading an article about this very thing back in the late 70s.
It was about the pilot and stunt coordinator James Gavin. Gavin was well know for being one of best helicopter pilots in Hollywood. He first started logging in many hours flying in Korea as a MASH helicopter pilot. When working in Hollywood if there was a helicopter being used, there was very good chance he was flying it.
As for the hanger shot, the article stated that Gavin was told by "experts" that the stunt was impossible to do. He was quoted to say "lets try it anyway."
The floor was watered down to prevent dust from kicking up and he was able to fly through hanger with no problem.
A similar movie to watch is Deadly Encounter, with Larry Hagman.
It's quite possible, as the hangar was a high-dome-roof type with no internal ceiling. The critical issue here is headspace over the rotors for air to flow from above and down through the rotors, as a helicopter can quickly suck itself right up to a ceiling if too close to it, with spectacular results.
Deadly Encounter, like Birds of Prey, was directed by William Graham and written by Robert Boris (he was co-writer for DE). Roger Gimbel was on both production teams.
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