Oct 24, 1947 In-flight fire caused the crash of a United Air Lines DC-6 at Bryce Canyon, Utah, with the loss of all 52 persons aboard. On Nov 11, another in-flight fire caused an American Airlines DC-6 to make an emergency landing at Gallup, N.M. Immediately following this second incident, the three airlines using DC-6 aircraft voluntarily withdrew them from service. The CAB determined that the fires had been caused by fuel leaking into the cabin heater system through an air intake scoop. After the problem had been remedied, the DC-6 returned to service in Mar 1948.
Medicine Bow Peak, Centennial, Wyoming,1955. DC-4.
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Possible incapacitation of crew by carbon monoxide emanating from a faulty cabin heater was speculated upon based on recovery crew observations that crew bodies appeared 'discoloured'. This theory was never proven.
Actors - Ricky Nelson
Ricky Nelson died in a DC3 crash in De Kalb, Texas in 1985. The crash was probably due to mechanical problems (including a faulty cabin heater).
An examination indicated the fire originated in the right hand side of the aft cabin area. The ignition and fuel sources could not be determined although many believe that the most likely cause was a defective cabin heater, a conclusion supported by records which showed that DC-3's in general, and this aircraft in particular, had a previous history of problems with the cabin heaters.