Goofs

During the jet boat sequence, Barney (Ken Wahl) is shown in close-up sitting upright in the back of the boat leaning back with arms up on the seat backs beside him, but in the distance shots showing the boat racing around, everyone is hunched over supposedly ducking the shots being fired at them, but also conveniently hiding their faces and disguising the fact that they are all stunt doubles.

During the jet boat chase, after one shooter falls out of the pursuing jet boat and it circles back to pick him up, immediately afterward they are suddenly right back behind the other jet boat with both running at full speed.

When Brown's goons confront Barney at the farm, the chopper is running. He even throttles it up to make his point clear. However, when Brown and his goons drive away, Barney jumps into the chopper, which is no longer running.

There were apparently two different chopper/tractor hybrids made. The one used for most of filming had exposed drive wheels between the tank-type tread and the hull of the vehicle. However, the vehicle that Brown stops on the road has narrow treads with no inner wheels, and the wheel rims inside of the tread are totally different from those on the vehicle in other scenes. The cockpit plexiglas on the vehicles differs between the scene where Brown stops them and every other scene involving the hybrid vehicle.

The Yankee Zephyr is called a DC-3 by the news announcer at the beginning, however it's a military version which is called a C-47.

There could never be an aircraft with the call sign "Yankee Zephyr". If it was an American aircraft of World War 2 vintage it would be "Yankee Zulu". If it was British, it would be "Yoke Zephyr". The two phonetic alphabets were distinct entities until the establishment of NATO, well after the end of World War Two.

When Brown's goons are trying to pull Gib out of the hybrid vehicle, the treads on the vehicle are clearly not moving, even though the vehicle is moving forwards. The hull of the vehicle is different, with the frame extending well in front of the helicopter cabin, giving away the fact that this was a model on rails.

When Sally (Lesley Ann Warren) is driving the jet boat she yells at the others, "Gotta turn around. Hang on! Look out!" But her mouth isn't speaking those words.

When Gilbert Carson first finds the whiskey in the Yankee Zephyr, he laughs and wheezes constantly for a while without stopping, but a couple shots of his face while he's laughing only show him smiling, and once he even appears to be saying something, but you can only hear him laughing and wheezing.