The Theory: The sky is so vast and your aircraft so small, there's almost no chance of a “midair” encounter
Of course we all know this theory is invalid and would never embrace such a blind course of aircraft avoidance. And yet so many of our actions validate the theory that we needn't look outside our aluminum tubes to see others that might share our airspace.
The classic “beak-to-beak” midair collision scenario came from the U.S. Air Force in the 1970s. It featured an F-4 Phantom II heading right at you, the closure speed was on the order of 900 kt. and you didn't stand a chance.
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