Investigation Summary
The incident occurred during the final stages of the Iran-Iraq War. The USS Vincennes had entered Iranian territorial waters while pursuing Iranian gunboats that had reportedly fired upon its helicopter. During this surface engagement, Flight 655 took off from Bandar Abbas, a dual-use civilian and military airport. The Vincennes' Aegis Combat System tracked the airliner, but human operators misinterpreted the data. Despite the aircraft transmitting a civilian Mode III transponder code and steadily climbing, crew members reported it was descending and squawking a military Mode II code. The Vincennes issued several warnings on military and international distress frequencies, but the airliner, not equipped for military radio and following its assigned civilian path, did not respond. The U.S. Navy's Fogarty Report later attributed the error to 'scenario fulfillment,' where the crew's high-stress environment led them to ignore data that contradicted their belief that an attack was imminent.
Final Conclusions
The ICAO investigation concluded that the aircraft was flying within the established Amber 59 airway and was transmitting civilian identification codes. The U.S. Navy's internal investigation (the Fogarty Report) concluded that the commanding officer acted based on information he believed to be correct at the time, though it acknowledged significant human factor errors in the Combat Information Center. In 1996, the United States and Iran reached a settlement at the International Court of Justice. The U.S. agreed to pay a total of $131.8 million, which included $61.8 million in compensation to the families of the 248 Iranian victims ($300,000 per wage-earner and $150,000 per non-wage-earner). While expressing 'deep regret,' the U.S. never formally apologized or admitted legal liability.
Photographic Evidence (1)
Video Analysis
The Shooting down of Iran Air Flight 655 in the Persian Gulf — A detailed look at the events leading to the USS Vincennes shooting down a civilian Airbus A300 during the Iran-Iraq War.
If playback is blocked, the owner has disabled embedding — use the link above.
Airframe & Maintenance
Crew Experience
Captain
Mohsen Rezaian, 38 years old, US-educated veteran.
First Officer
31 years old. Had at least 2,000 flight hours.
Flight Engineer
33 years old. Had at least 2,000 flight hours.
Systems & Failure Modes
Aegis Combat System
An advanced integrated naval weapons system that correctly tracked the aircraft's altitude and speed, though its data was misinterpreted by the crew.
IFF (Identification Friend or Foe)
The transponder system used to identify aircraft; the Vincennes crew incorrectly believed the aircraft was transmitting a military squawk.
SM-2MR Missile
The medium-range surface-to-air missiles used by the USS Vincennes to destroy the airliner.
Interesting Facts
- 01The aircraft was within the 20-mile-wide Amber 59 civilian air corridor at the time of the shootdown.
- 02The USS Vincennes was inside Iranian territorial waters when it fired the missiles.
- 03The airliner was squawking a civilian Mode III transponder code, not a military Mode II code.
- 04The crew of the Vincennes misidentified the aircraft as an F-14 Tomcat.
- 05Seven of the ten warnings issued by the Vincennes were on a military frequency the airliner could not receive.
Safety Actions & Advisories
IFF Procedure Revision
The U.S. Navy revised procedures for identifying civilian aircraft in combat zones to prevent 'scenario fulfillment' errors.
Civil-Military Coordination
Improved communication protocols were established between military vessels and regional Air Traffic Control to verify civilian flight schedules.
Known Controversies & Unanswered Questions
Disputed Identification Data
Reference ↗While the Vincennes crew claimed the aircraft was descending and squawking military codes, data from the ship's own Aegis system and the nearby USS Sides confirmed the plane was climbing and squawking civilian codes.