Narrative: Pan Am flight 843 experienced an explosive disintegration of the third stage turbine disk of the No. 4 engine. The accident occurred shortly after takeoff from San Francisco, at an altitude of about 800 feet above the ground. Disintegration of the turbine disk was followed by a fire in the No. 4 engine area and an explosion in the outboard reserve fuel tank. The No. 4 engine and approximately 25 feet of the right outer wing separated from the aircraft. The fire was extinguished and a successful emergency landing was accomplished at Travis Air Force Base, California, with no injuries to the 143 passengers or 10 crewmembers aboard the flight.
PROBABLE CAUSE: "The failure of the third stage turbine disk. This failure was caused by a transient loss of operating clearance between the third stage turbine disk and the third stage inner sealing ring. This loss of clearance resulted from a combination of improper turbine rotor positioning during engine assembly, the use of serviceable worn parts, and an operating clearance which was less than predicted in design analysis."
Taken from rear of right wing. Outboard pylon can be seen under wing.
Video, social media
This map shows the airport of departure and the intended destination of the flight. The line between the airports does not display the exact flight path. Distance from San Francisco International Airport, CA to Honolulu International Airport, HI as the crow flies is 3831 km (2395 miles).