Investigation Summary
The accident was the result of a combination of poor Crew Resource Management (CRM) and a technical vulnerability in the Fokker 50's propeller control system. During the flight, the Captain pressured the First Officer into performing the landing despite the First Officer's lack of confidence. This led to an unstable approach where the aircraft was 50 knots faster and significantly higher than the standard profile. In an attempt to salvage the landing, the Captain took control and pulled the thrust levers into the ground range. Technically, the Fokker 50 was equipped with secondary stops to prevent in-flight reverse thrust. However, a design flaw existed where electromagnetic interference from the anti-skid control unit, triggered by landing gear extension, could falsely energize the flight solenoids for approximately 16 seconds. This glitch tricked the system into 'thinking' the aircraft was on the ground. Although Fokker had issued a mandatory modification to fix this after a similar crash in 2002 (Luxair Flight 9642), the accident aircraft was not scheduled for the update until May 2004. When the Captain manually lifted the ground range selectors during this 16-second window, the safety locks (solenoids) failed to provide resistance because they were already energized by the glitch, allowing the propellers to move into full reverse and causing an irrecoverable pitch-down and roll.
Final Conclusions
The primary cause was the pilot's unauthorized use of the ground range of the thrust levers while in flight. Contributing factors included the unstable approach caused by poor cockpit coordination, the Captain's decision to switch roles late in the flight, and the failure to implement a mandatory modification to the anti-skid control unit that would have prevented electromagnetic interference from disabling the propeller safety locks.
Video Analysis
How A Scared Pilot Ended Up Killing 46 People | Kish Air Flight 7170 — A detailed breakdown of the unstable approach and the technical failure of the propeller pitch locks that led to the crash of Kish Air 7170 in Sharjah.
If playback is blocked, the owner has disabled embedding — use the link above.
Airframe & Maintenance
Crew Experience
Captain
Ahmed Hosseini, a former military pilot.
First Officer
Nemat Panahian.
Systems & Failure Modes
Thrust Lever Ground Range Selector
A manual lock that must be lifted to move thrust levers into the reverse/ground range, intended to be used only on the ground.
Anti-Skid Control Unit
A system that prevents wheel lock-up during braking; a flaw in its wiring caused electromagnetic interference that disabled propeller safety stops.
Secondary Flight Stop Solenoids
Electromagnetic locks designed to prevent the propellers from entering a low-pitch or reverse range while the aircraft is airborne.
Interesting Facts
- 01The aircraft was a Fokker 50 registered EP-LCA, powered by Pratt & Whitney Canada engines.
- 02The crash was nearly identical in mechanics to the 2002 Luxair Flight 9642 accident.
- 03Three passengers survived the initial impact and fire: one Egyptian, one Filipino, and one Iranian.
- 04The anti-skid control unit was in an unmodified state, allowing electromagnetic interference to bypass safety solenoids.
- 05Most passengers were migrant workers traveling to renew their UAE visas.
Safety Actions & Advisories
Visa Policy Reform
Following the crash, the UAE government abolished the requirement for migrant workers to exit the country to renew their visas, a policy that had created the high demand for 'visa runs' to Kish Island.
Mandatory Anti-Skid Modification
Aviation authorities reinforced the urgency of Fokker Service Bulletins regarding the modification of anti-skid units to prevent electromagnetic interference with propeller pitch controls.