When Grossman reads aloud the address of the war museum, he says the street number is 3456, yet when Ponch and Jon go to the museum the next day to investigate, the number above the door is 645.
When Gatrear and Harlan are playing chess, Gatrear is elated when he puts Harlan in check. Harlan responds by moving a piece and putting Gatrear into checkmate. Harlan would have to get himself out of check before he could make his checkmate move.
The jet pack was said to have a maximum of 20 seconds of use time, yet during his escape Rascoe uses it for 38 seconds. At 20 seconds, he was high in the air and would have fallen once it cut off, likely resulting in injury and his escape failing.
The wires that hold the jet pack in the air are visible when it flies in the sun's glare.
While visiting the war museum, Darla overhears the crooks' plan; she then makes a noise and disguises herself just to serve one of the crooks. Since she already saw the man she's planning to serve enter the building, it's unclear why she goes to all the trouble to dress up and not just serve him.