Investigation Summary
The aircraft was on the 14th day of a multi-city Asian tour chartered by the Tjæreborg travel agency. After a refueling stop in Tehran, the Caravelle was taxiing toward the runway for its final leg back to Copenhagen. The right main landing gear assembly collapsed while the aircraft was initiating a turn. The resulting impact between the wing and the taxiway surface breached the integral fuel tanks. The spilled fuel ignited immediately, engulfing the right side of the fuselage in flames. The investigation, conducted by Iranian authorities with assistance from the Danish Accident Investigation Board, focused on the mechanical integrity of the landing gear. Technicians identified a specific structural failure in the lower candelabra fitting of the undercarriage, which was unable to support the weight of the aircraft during the maneuver.
Final Conclusions
The accident was caused by the structural failure of the lower candelabra fitting in the right main landing gear. This failure led to the collapse of the gear, the rupture of the right wing fuel tank, and a subsequent ground fire that claimed 15 lives.
Video Analysis
Sterling Airways Flight 901 Aftermath Footage | 15 March 1974 — Historical footage and details regarding the landing gear failure and fire involving a Sterling Airways Caravelle in Tehran.
If playback is blocked, the owner has disabled embedding — use the link above.
Crew Experience
Captain
Leif Knud Jørgensen, age 38 (Danish)
Co-Pilot
Raimo Uski (Finnish)
Systems & Failure Modes
Main Landing Gear
The assembly responsible for supporting the aircraft weight on the ground; a failure in the 'candelabra' fitting caused the collapse.
Fuel System
Integral tanks located within the wings; the right tank was breached when the wing struck the ground following the gear collapse.
Interesting Facts
- 01The aircraft made its first flight on April 4, 1970, and was delivered to Sterling Airways on May 6, 1970.
- 02The fire killed 7 Danish and 8 Swedish passengers.
- 03The investigation ruled out pilot error, focusing entirely on the structural integrity of the undercarriage.
Safety Actions & Advisories
Landing Gear Fitting Inspection
Following the identification of the 'candelabra' fitting failure, investigators and the manufacturer focused on the propagation of fatigue cracks in the lower right-hand main gear assembly to prevent similar structural failures in the Caravelle fleet.