Pan American’s Flight 1-10, originating in San Francisco, April 10, 1948, was scheduled to fly around the world to New York. In accordance with company practice the flight changed to a different aircraft, NC88858 “Clipper Empress of the Skies”, in Calcutta, India. The flight took off from Calcutta, April 13, 1948. Intermediate stops were made at Damascus, Istanbul, Brussels. During a night landing approach at Brussels the fluorescent lighting on the left side of the cockpit went out. Since the only other lighting immediately available was a chart light which was focused on the automatic direction finder indicator, the flight instruments could not be read, and the remainder of the landing approach was accomplished without visual reference to the flight instruments. After landing, the lights appeared to operate normally so the flight departed for London. On final approach to London, the lights again went out. On the ground at London the defect was detected, but could not be repaired because of a lack of a spare part. At 00:35 the Constellation departed London for a flight to Shannon. At 01:59, the flight reported being at an altitude of 4,500 feet over the Limerick Junction fan marker and requested permission to make a practice ILS approach. At 02:10, while the flight was over the outer marker, Shannon Tower advised the flight that the weather over the field was “fog patches, 3 miles visibility, cloud base 400 feet, sky 6/10 covered, wind from 325 degrees at 4 miles per hour.” Clearance was given to land at runway 23. Ten minutes later the flight reported a missed approach. The flight crew positioned the plane for a second approach. While on final approach, the Constellation struck a stone fence, located short of the runway. The undercarriage was destroyed upon impact and all four engines were torn from the wing. The fuselage broke in three and came to rest about 600 feet further on. PROBABLE CAUSE: “The Board determines that the probable cause of this accident was the continuation of an instrument approach to an altitude insufficient to clear the terrain. Failure of the fluorescent instrument light may have been a contributing cause.”