Other mistake: During the big chase scene, a car hits a camera right after it passes a blue '68 GTO.

Other mistake: Just before the Charger crashes, a tow bar connecting both vehicles is visible on the Mustang's front bumper.
Other mistake: When we get a front shot of the two cars jumping the hills, watch when the Mustang lands on all four wheels. It gives out a tremendous amount of smoke and steam from underneath. (Slow it down on DVD for the full effect.) This is because the car landed too heavily and shattered the sump (oil pan). The other Mustang had to be used while the mechanics repaired the damage.
Answer: Airport security in the late 1960's was not nearly as thorough as it is in present day. Metal detectors didn't become commonplace at airports until the early 1970's.
BaconIsMyBFFIt was the D.B. Cooper hijacking of a Boeing 727 commercial jet in 1971 that radically changed how airport security was handled. Before that, there was virtually little to no pre-boarding security checks.
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