Incident Description
During climb after takeoff, the first officer (FO) was flying the aircraft when the cabin failed to pressurize. The FO began leveling off at 16,000 feet, but the captain ordered him to continue climbing to the assigned flight level of FL 330 while the captain went aft to find the problem. The FO disliked the order but complied rather than confront the captain. The captain left the cockpit with a portable 'on demand' oxygen system, which had a 15-minute supply of oxygen.
When the captain did not return, the FO tried signaling him. Although reluctant to countermand the captain's order, the FO made a series of descents to 13,000 feet. After about 30 minutes, the FO left the cockpit and found the captain unconscious and unresponsive in the forward cargo area with the oxygen mask on his face. The captain's foot was entangled in a cargo net covering a pallet. The FO tried to revive the captain to no avail, then declared an emergency and landed at Lubbock.
The captain was rushed to a hospital but was dead on arrival.
Investigation Findings
Examination revealed that the aft pressure bulkhead was not installed; it had been removed for maintenance before the flight. The portable oxygen system was still full, indicating the captain had little or no use of it. The system was tested and functioned normally. A group of eight forensic pathologists concluded that the captain died from hypoxic hypoxia.