Grading the guardians: NORAD evaluations a vital requirement
They’re heard before they’re ever seen. Even over the engines of an Airbus A310, a distinct roar causes a vibration a person can feel in their chest, prompting them to look out the window and find that the airplane they’re sitting in is now sharing airspace with an F-16 fighter jet. Close enough to see that, even as they’ve turned to look at the fighter’s helmeted pilot, that pilot has turned to look at them.
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