Story highlights Air Force pilot backs up first officer during medical emergency last December

A United 737 from Iowa to Colorado diverted to Nebraska

Pilot handled radio communication with controllers while first officer landed the plane

He kept quiet about his story until recently when reporters asked the Air Force

(CNN) It sounds like the plot from an old movie: airline crew members make this passenger announcement, "Is anyone on board a pilot?"

That was the situation last December when Air Force Capt. Mark Gongol and his wife and daughter were traveling from Des Moines to Denver aboard a United Boeing 737.

"I looked at my wife and she looked back at me and she said, 'I think you should ring the call button,'" Gongol told CNN on Tuesday.

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Gongol, who pilots B1B Lancer bombers, already could tell something was wrong. Flight attendants were rushing to the front of the aircraft. One was carrying a first-aid kit.

When Gongol reached the cockpit, it was clear the captain was in trouble. Passengers and crew were helping him out of the cockpit. A cot had been set up. The captain looked pale and clammy from an apparent heart attack, Gongol remembered.

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