The MD500 Airwolf shoots down is black, but the exploding wreckage is a red and white MD500.
Marilyn reports to Hawke, while he's in the hospital, that the bullet that hit him nicked an artery. It takes only minutes for a person to die if an artery is cut, and Hawke had been running around for much longer than that.
Mr. Santini removes a bug from the mouthpiece of a telephone. However, this would only prevent a listener from hearing what Mr. Santini said, as a telephone bugging of this sort would also have a bug in the earpiece.
The tunnel that Mr. Hawke takes the helicopter into has a different design in the close up shot of it entering and leaving the tunnel.