Plot hole: Apart from the impressive pyrotechnics, what is the point of destroying the Blue Thunder helicopter? By far the most expensive, time consuming and technically complex part of producing any aircraft is the design and development phase - once the prototype is in the air production is relatively straightforward. The bad guys can make new Blue Thunders any time they like, and Murphy has destroyed the only evidence he has that there was a criminal conspiracy behind the whole programme - the 'videotape' he has of blurry, false coloured characters will convince nobody. Without the helicopter to back him up that tape is of no value to him.
Factual error: Cochrane chases Murphy in a Hughes 500 which has a top speed of 147 mph and easily keeps up with him, demonstrating that Blue Thunder's top speed is less than 150 mph. The F-16s sent after Blue Thunder have a stall speed of 175 mph. They would have to slow down to the point of falling out of the sky to have a shot at Murphy. Its utterly impractical and far more likely that the military would have sent AH-1 Cobra attack helicopters after him.