My Dad served in the US Navy during WW2. He liked to say, "I served with Nimitz... (pause) ...along with a couple million other guys." He was an Electrician's Mate, tasked with servicing the radars and radar altimiters of the new night fighters such as the F6FN Hellcat and F7F Tigercat. Most of his time in service was spent in Florida. He never saw combat. (His older brothers and in-laws saw their share, though. One was a paratrooper at Normandy and The Bulge, another lost a finger to a Howitzer breech mechanism somewhere in France, another had several ships torpedoed out from under him in the Merchant Marine.) Dad had some good stories, though. Here's one:
Dad was training new F6F pilots (excuse me - Naval Aviators) how to use their radar altimiters.
He explained how the unit shot a radio pulse (traveling at the speed of light) down to the water's surface, and measured the time until the reflected pulse was received. The altimeter automatically converted the travel time of the radio pulse into altitude above the water. (The unit had a toggle switch that would set its sensitivity to +/-50 ft or +/-500 ft. Quite a few pilots died in training until it was realized that they'd left the switch at "+/-500" while flying below 100 feet. They figured it out after fishing a few of the birds out of the drink and noticing the switch position.)
During one training session, one hotshot Naval Aviator was lounging back and clearly not paying much attention. Dad said, "Hey - you don't think this is important?" The flyboy replied, "Man, I'm cruising at three hundred miles per hour. By the time your little ray-di-oh blip bounces off the water, I'm looong gone!"