This early '80s clip shows a United States Air Force B-52 bomber and its crew rehearsing the steps involved in an emergency mission.

Begins with a B-52 in a hanger, getting inspected by its flight crew and technicians. 

A squad commander gives instructions to B-52 pilots in a classroom.

Pilots and crew hurriedly leave their unit headquarters to fly a mission. Trucks leave the headquarters in an orderly fashion, headed to the airstrip. 

Pilots and crew exit their vehicles and scramble to their B-52 planes and prep them for takeoff.

A B-52 takes off from the airstrip, cruising through the sky with lights on. The sun sets as a B-52 flies in the foreground. We eventually see the B-52 return to the airstrip for a landing; dark exhaust is seen in the plane's wake.