Slip Up

The action begins on an airplane. The two Pilots are doing two women in the cockpit. Near scenes end the plane loses control (from no one piloting) and they eject with parachutes. The head Pilot and his girl are still getting it on as they float down, and she says that he has to keep up his Johnson or she will fall. He of course ejaculates and she slips off.
The plot of this is about a Mad Scientist planning on turning his machine on full blast by the end, so everyone in the world will get hot. He has a young, blonde, Female assistant.
One scene involves a young, Black couple getting it on at a Radio Station.
The other is at a Restaurant where a guy and 2 girls go at it under their table. A snooty (French?) Waiter keeps interrupting them and acts casual about it. The Restaraunt parts have a Doo-Wop parody song playing throughout.
I'm under the impression that the title had the word 'BLAAAK!' or 'YAAAK!', something like those words, that popped up at the ending before the credits rolled.