Trip
1943-JAN-21 · 7 miles SSW of Ukiah, Mendocino County, California

Pan American Airways — Flight Trip 62100 (Flight V-1104)

Pan Am Flight 1104, a Martin M-130 flying boat known as the Philippine Clipper, crashed into a mountain in Mendocino County during a storm, killing all 19 people on board. The aircraft was operating a military transport mission for the U.S. Navy, carrying high-ranking officers, including Rear Admiral Robert H. English, Commander of the U.S. Pacific Submarine Fleet. Aided by strong tailwinds, the flight arrived off the California coast hours ahead of schedule but encountered severe weather, including heavy rain and fog. The captain descended to a dangerously low altitude while off course, striking a mountain at approximately 2,500 feet.

Aircraft
Martin M-130
Registration
NC14715
Phase
Cause
Souls on Board
19
Fatalities
19
Origin → Dest
Pearl Harbor, Oahu, Hawaii → San Francisco Municipal Airport, California
Report

Investigation Summary

The Philippine Clipper was one of only three Martin M-130 flying boats ever built. During World War II, it was pressed into Navy service as Flight V-1104, though it remained operated by experienced Pan American personnel. The flight departed Pearl Harbor at 17:30 on January 20, 1943. Due to a powerful tailwind, the aircraft reached the California coast three and a half hours ahead of its expected arrival time. As the aircraft approached the San Francisco area, it encountered a severe winter storm with winds strong enough to blow over trees. A Civil Defense aircraft spotter reported seeing the plane flying very low with its lights on before it disappeared into the storm. The aircraft crashed at a 10 degree angle into a mountain ridge southwest of Ukiah, clipping trees before breaking up and burning. Because the flight carried the commander of the Pacific Submarine Fleet and potentially classified documents, the crash site was cordoned off by the military for over a week until the wreckage was fully processed.

Final Conclusions

The Civil Aeronautics Board (CAB) determined the probable cause was the failure of the captain to determine his position accurately before descending to a dangerously low altitude under extremely poor weather conditions during the hours of darkness. The investigation highlighted that the aircraft was significantly off course when the descent was initiated.

Video Analysis

No video analysis linked for this case file yet.

Airframe & Maintenance

Airframe Hours
14,628
Engines
4 Pratt & Whitney R-1830-S2A5G

Crew Experience

Captain

Total hours
4,941

Robert M. Elzey. Temple University graduate (1929) in Aeronautical Engineering. Trained at Naval Air Station Pensacola. 3,359 hours were with Pan American.

First Officer

Total hours
694

Orvan K. Judd. Completed five courses of the Civilian Pilot Training (CPT) Program. Employed by Pan American since November 1941.

Systems & Failure Modes

i

Martin M-130 Flying Boat

A large four-engine flying boat designed for trans-Pacific service; only three were ever produced. The Philippine Clipper entered service in 1936 and cost $417,000.

i

Pratt & Whitney R-1830-S2A5G

The four radial engines powering the aircraft, which had logged 14,628 total airframe hours as of the time of the accident.

Interesting Facts

  • 01The aircraft was the Philippine Clipper, which had survived the Japanese attack on Wake Island in December 1941.
  • 02All 10 passengers were U.S. Naval officers, including the Commander of the U.S. Pacific Submarine Fleet.
  • 03The flight was three and a half hours ahead of schedule due to strong tailwinds.
  • 04The crash site was located at an elevation of approximately 2,500 feet.
  • 05The aircraft struck the ground at a 10 degree angle after clipping trees.

Location

7 miles SSW of Ukiah, Mendocino County, California · 39.0667, -123.2833

Case File History

  1. New evidenceUpdated event timeline and systems analysis.

Related Cases

Case ID · pan-am-1104-1943Last updated · Filed

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