"The crew of the doomed 1999 Learjet became incapacitated following a loss of cabin pressurization and failure to receive supplemental oxygen."
The NTSB investigated the 1999 Learjet accident and concluded that the crew became incapacitated after the aircraft lost cabin pressurization and they failed to receive supplemental oxygen. The report establishes the human-incapacitation scenario that makes autonomous emergency recovery an important aviation safety problem.
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