Investigation Summary
The investigation into Flight 816 was severely hampered by the depth of the crash site. The Boeing 707 struck the water approximately 3 kilometers northeast of the airport and sank into a trench 700 meters (2,300 feet) deep. At the time, recovery technology was insufficient to retrieve the Cockpit Voice Recorder (CVR) and Flight Data Recorder (FDR). Investigators were forced to rely on eyewitness accounts from the terminal and the limited maintenance history of the airframe. Two primary mechanical theories were explored: an asymmetric flap retraction or a catastrophic failure of the windshield that had been reported as cracked earlier that day. However, the lack of physical evidence meant neither could be proven. Human factors also played a significant role in the analysis, specifically the 'black hole' effect of taking off over a featureless ocean at night, which is a known trigger for spatial disorientation.
Final Conclusions
The French Bureau d'Enquêtes et d'Analyses (BEA) concluded the cause was undetermined. The report noted it was possible that an instrument failure diverted the crew's attention during the turn. Given the lack of visual references over the dark sea, the crew may have succumbed to spatial disorientation, leading to an excessive bank angle and descent that went unnoticed until impact.
Photographic Evidence (1)
Video Analysis
No video analysis linked for this case file yet.
Airframe & Maintenance
Crew Experience
Captain
Robert M. Evarts, age 59.
First Officer
Lyle C. Havens, age 59.
Flight Engineer
Isaac N. Lambert, age 34.
Navigator
Frederick W. Fischer, age 32.
Systems & Failure Modes
Cockpit Windshield
A crack was reported after the first leg; though deemed minor, it may have failed or distracted the crew during climb.
Wing Flaps
Investigators considered a possible asymmetric retraction which could cause an uncommanded roll.
Flight Recorders
Both the CVR and FDR were lost in deep water and never recovered, preventing a definitive cause from being found.
Interesting Facts
- 01The aircraft was named Clipper Winged Racer.
- 02Only one passenger survived the crash; all 10 crew members and 68 other passengers perished.
- 03The flight was delayed 90 minutes due to a reported crack in the cockpit windshield.
- 04The aircraft was significantly heavier than planned, carrying 156,220 pounds of fuel instead of 121,000 pounds because the crew planned a lower altitude flight due to the windshield crack.
- 05The crash occurred in total darkness over the ocean with no visible horizon.
- 06The crew did not acknowledge the final takeoff clearance from the controller, which may indicate early cockpit distraction or a radio issue.
Safety Actions & Advisories
CRM Culture Reform
The accident was one of several in a period that led Pan Am to eventually overhaul its Crew Resource Management (CRM) training and cockpit culture.