Investigation Summary
The flight was a multi-stop charter picking up recruits across the Northeastern U.S. During earlier legs, the flight engineer noticed fuel pressure fluctuations in the number 3 engine and opened cross-feed valves to compensate. By leaving these valves open for extended periods, the crew inadvertently drained the number 4 fuel tank dry, causing both right-side engines (3 and 4) to fail while en route to Columbia. The crew diverted to Richmond, but the cockpit environment was characterized by confusion; both pilots were qualified captains, and their roles as pilot-in-command and co-pilot were poorly defined during the emergency. As they approached Richmond, the co-pilot (acting as the more senior officer) suddenly attempted to land on Runway 2 instead of the assigned Runway 33. Because the right-side engines were dead, hydraulic power to the landing gear was unavailable, and the gear failed to extend. The crew attempted a go-around on the two remaining left-side engines, but the number 1 engine failed due to overboosting during the maneuver. With only one engine functioning, the aircraft could not maintain altitude and crashed into a wooded area one mile short of the runway threshold and half a mile to the left of the extended runway centerline.
Final Conclusions
The Civil Aeronautics Board (CAB) determined the probable cause was the lack of command coordination and decision, lack of judgment, and lack of knowledge of the equipment. This resulted in the loss of power in three engines, creating an emergency situation the crew could not handle. The CAB was highly critical of Imperial Airlines, stating the crew was not capable of performing their functions and that management had condoned substandard maintenance and operational practices.
Video Analysis
No video analysis linked for this case file yet.
Airframe & Maintenance
Crew Experience
Captain
Ronald H. Conway; acted as Pilot-in-Command. Survived.
First Officer
James A. Greenlee; a qualified captain who acted as co-pilot. Fatal.
Flight Engineer
William F. Poythress. Survived.
Systems & Failure Modes
Fuel Cross-feed System
Mismanagement of the cross-feed valves allowed the No. 4 tank to be exhausted while other tanks still contained fuel, leading to starvation of both right-side engines.
Hydraulic System
On the L-049, hydraulic power for the landing gear was supplied by the two right-side engines; their failure rendered the normal gear extension system inoperative.
Wright R-3350 Cyclone Engines
The No. 1 engine failed during the emergency go-around because the crew exceeded its power limits (overboosting) while trying to maintain altitude on only two engines.
Interesting Facts
- 01All 74 passengers and 3 crew members died from carbon monoxide asphyxiation; only the Captain and Flight Engineer survived.
- 02The aircraft was a Lockheed L-049E Constellation manufactured in 1946.
- 03The flight was a 'nonsked' (non-scheduled) charter, a sector that was statistically 30 times more dangerous than scheduled airlines at the time.
- 04The two pilots had agreed before the flight that the more junior captain would act as Pilot-in-Command while the senior captain acted as First Officer.
- 05Captain Conway testified that student flight engineer Peter Clark was at the controls during the flight, while the surviving Flight Engineer Poythress denied this, claiming he was at the station during the final leg.
Safety Actions & Advisories
Supplemental Carrier Regulation
In 1962, Congress passed legislation requiring all supplemental carriers to re-apply for CAB certification, carry liability insurance, and demonstrate financial stability.
Military Charter Reform
The accident led to a sweeping probe of the 'nonsked' industry and changes in how the Pentagon bid for troop transport to prioritize safety over the lowest bidder.
Known Controversies & Unanswered Questions
Flight Engineer Station Occupancy
Captain Conway and Flight Engineer Poythress gave conflicting testimony regarding whether Poythress or the student engineer, Peter Clark, was at the controls during the critical phases of the flight.