Investigation Summary
The flight was a transport mission returning General Sikorski to London following an inspection of Polish forces in the Middle East. The aircraft, serial number AL523, was a Liberator C II operated by No. 511 Squadron of RAF Transport Command. According to the surviving pilot, Eduard Prchal, the takeoff run and initial climb were normal until the aircraft reached 150 feet. When Prchal pushed the nose down to gain airspeed, he found the elevator controls were jammed, preventing him from pulling back to resume the climb. The aircraft gradually lost altitude and impacted the sea approximately 1,200 yards from the end of the runway. Prchal managed to close the throttles and warn the occupants before impact. Rescue teams reached the site within six minutes, but only Prchal was recovered alive. The bodies of Sikorski and several others were recovered, but five victims, including Sikorski's daughter Zofia Lesniowska, were never found.
Final Conclusions
The British Court of Inquiry, which concluded its initial investigation on 25 July 1943, determined the cause was the jamming of the elevator controls for reasons that could not be established. While the court ruled out sabotage, Air Marshal Sir John Slessor expressed dissatisfaction with the lack of a specific mechanism for the jam and ordered further investigation, which remained inconclusive. A 2008 investigation by the Polish Institute of National Remembrance (IPN) involved the exhumation of Sikorski's remains; medical experts concluded he died of injuries consistent with a plane crash, ruling out theories that he was murdered prior to the flight. The IPN closed its investigation in 2013, stating there was insufficient evidence to either confirm or exclude sabotage.
Video Analysis
No video analysis linked for this case file yet.
Systems & Failure Modes
Elevator Controls
The primary flight control surfaces used to control the aircraft's pitch; the pilot reported these were physically jammed during the climb.
Autopilot
A system to automatically maintain flight path; later theories suggested its engagement during takeoff could mimic a control jam.
Interesting Facts
- 01General Wladyslaw Sikorski was the Prime Minister of Poland and Commander-in-Chief of the Polish Armed Forces.
- 02The pilot, Eduard Prchal, was the only person to survive the crash.
- 03The aircraft became airborne after a run of approximately 1,100 yards and struck the sea 1,200 yards after leaving the ground.
- 04The British Court of Inquiry ruled out sabotage in 1943, though the Polish government-in-exile refused to endorse the report.
- 05Post-war analysis by Jerzy Zieborak in 2012 suggested the aircraft may have been overloaded and the autopilot inadvertently engaged.
Known Controversies & Unanswered Questions
Sabotage and Assassination Theories
Reference ↗Due to Sikorski's strained relations with the Soviet Union following the discovery of the Katyn massacre, numerous theories suggest the crash was an assassination orchestrated by Soviet, British, or rival Polish factions.