Airwolf (a.k.a. Shadow of the Hawke) - S1-E1
Revealing mistake: As the camera has a closeup on Moffet driving the jeep, the shadow of the camera rig plays across the windshield.
Proof Through the Night - S1-E4
Revealing mistake: As Airwolf flies at high speed across the countryside to get away from Russia, the shadow of the camera chopper can be seen on the ground, rather than the Bell 222 Airwolf.
Proof Through the Night - S1-E4
Revealing mistake: As Hawke uses the Star Light Amplification System to see where he's flying, the readout shows what he's looking at. The electronic compass readout at the top of the display doesn't move, even though the picture shows that he's constantly twisting and turning, following the terrain.
Proof Through the Night - S1-E4
Revealing mistake: As the camera flies over the ranch and house (simulating Airwolf's flight), the camera chopper's left skid is visible in the lower left corner of the shot. Airwolf is a Bell 222 with added features, and doesn't have skids.
Chosen answer: Archangel and the Firm provided fuel and armaments. Dom and Hawke would have had to transport them to the lair to refuel and rearm.
Grumpy Scot