A small white plane has no registration number on its side on the ground, but the registration number is clearly visible in flight.
A boat at the lake changes completely between shots.
Near the beginning of the film, the airplane speeds down the runway. When Harry arrives, the plane is standing still.
During a jump, one skydiver wears a white jumpsuit in closeup shots, but in long shots and when they land, both wear dark jumpsuits.
When Tony makes his first jump, he puts on a small white helmet with no markings on it. Then when he is airborne and about to make his jump from the plane there is a small label with "61" on his helmet, then after he jumps and is floating to the ground the label disappears.
At dinner, Beth's hair slips forward, revealing itself to be a wig.
As a car pulls up to the plane the passenger door comes open and the driver never bothers to close it.
The name "Suzy" on Suzy's boat has the Z on backwards.
After Beth brings the sputtering plane to a stop, a large group of people appears in the upper right corner of the screen.