I got this slip-up from watching the Airplane! DVD with the audio commentary on from the producers where they explained it. Go to the part where Ted is in the bar and is disco dancing. Ted puts his legs up on Elaine and she spins him around. After she lets go, his legs fly off the screen and he does a backflip. Now pay attention. Look at when he does a backflip (stuntman). He is supposed to crash in the crowd and disappear for a second. He then jumps out do the dance floor and you hear that diving-board sound. Righ after he does the origional backflip, the stuntman goes into the crowd. You can actually see the actual Ted Striker (Robert Hays) in the background crouching over ready do jump into the crowd. It migh take a minute to know what I mean but look at it, it's hilarious! Just a commmon placement slip-up.