United Airlines Flight 624

United Airlines Flight 624, a Douglas DC-6 airliner, registration NC37506, was a scheduled passenger flight that originated in San Diego, California with stops in Los Angeles and Chicago en route to LaGuardia Airport in New York City. The four-engine propeller-driven airplane crashed at 1:41 p.m. Eastern Daylight Time on June 17, 1948 outside of Aristes, Pennsylvania, killing all 4 crew members and 39 passengers on board.
Flight 624 from San Diego had just completed a routine initial descent as part of its approach into the New York area, when the forward cargo hold fire indicator light illuminated, leading the flight crew to believe there was a fire in that cargo hold. Although this later turned out to be a false alarm, the crew decided to discharge CO2 bottles into the forward cargo hold, to try to extinguish the possible fire.

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