Penciled Warning: How a Suppressed Report Killed 43 on DC‑6

Penciled Warning: How a Suppressed Report Killed 43 on DC‑6

A suppressed safety report marked with four penciled words - "Do not discuss with CAA" - preceded a crash that killed 43 people fourteen days later, raising the chilling question: how did documented knowledge about a CO2 hazard vanish before it could save lives? What exactly was buried, and who decided it should stay hidden?

In this episode, we lay out the sequence of events recorded in the report, the technical details of the Douglas DC-6 fire-suppression system, and who was on United Air Lines Flight 600 when the warning light came on - and then the CO2 was discharged. How did a finding that a test pilot was "almost completely out" after a CO2 release fail to reach the crews who needed to know?

Person: Earl Carroll Person: Beryl Wallace Person: Henry L. Jackson Event: United Air Lines Flight 600 crash Aircraft: Douglas DC-6 (registration NC-37506)

- The report was dated February 1948 and stamped with the instruction "Do not discuss with CAA." - The crash occurred fourteen days after the report was suppressed. - Forty-three people died on a hillside near Mount Carmel, Pennsylvania. - The DC-6 entered commercial service in 1947 and was grounded by the CAB in November 1947 after two in-flight fires. - During a company test, a pilot who discharged the DC-6 CO2 system was described in the report as being "almost completely out" due to CO2 migration into the flight deck.

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