I saw an interview with him once where he was telling a story about flying with the real Pappy Boyington. Robert Conrad had earned his Private Pilot Certificate in order to prepare for the roll. He said he later bought a Bonanza (I think) and used to fly it back and forth to the set. One time he said he flew with the real Pappy Boyington, who convinced him to let him try landing the plane. I guess they ended up clipping a fence as they came in a little low and Robert Conrad had to do a little explaining about that. It was pretty funny the way he told the story.