Investigation Summary
The flight departed into a 'pitch black' sky over the Red Sea, providing no external visual references. Shortly after takeoff, while performing a climbing turn, the aircraft began to bank to the right instead of following the intended flight path. The Captain, who had significant experience in military aircraft but relatively low hours on the Boeing 737, appears to have suffered from spatial disorientation. The First Officer's attempts to intervene were delayed and hesitant, likely due to the steep hierarchy in the cockpit. By the time the crew recognized the extreme bank angle (which reached 111 degrees), the aircraft was in a high-speed dive from which recovery was impossible.
Final Conclusions
The Egyptian Ministry of Civil Aviation concluded the cause was undetermined but suggested several technical possibilities including a temporary spoiler jam. However, the NTSB and BEA strongly favored spatial disorientation (the 'dark hole' effect) and poor Crew Resource Management (CRM) as the primary factors, noting that the aircraft's flight path was consistent with a pilot following a false sensation of bank.
Video Analysis
Flight 604's Mysterious Crash Over the Red Sea | Mayday: Air Disaster — An investigation into the crash of Flash Airlines Flight 604, exploring the conflicting theories between international investigators regarding mechanical failure versus pilot error.
Watch on YouTube ↗If playback is blocked, the owner has disabled embedding — use the link above.
Systems & Failure Modes
Autopilot (Flight Management Computer)
Investigators disputed whether the autopilot failed to engage properly or if it disconnected due to pilot input.
Aileron/Spoiler Actuators
Egyptian investigators suggested a potential 'hardover' or jam in the lateral control system, though no physical evidence supported this.
Attitude Indicator
The primary instrument for determining aircraft orientation, which the NTSB believed the pilots failed to monitor effectively.
Interesting Facts
- 01The accident remains the deadliest involving a Boeing 737 Classic aircraft.
- 02The majority of the passengers (132) were French tourists returning from vacation.
- 03The wreckage was located at a depth of approximately 1,000 meters (3,300 feet).
- 04The Captain was a highly decorated former Egyptian Air Force pilot.
- 05Flash Airlines was banned from Swiss airspace prior to the accident due to safety concerns.
Safety Actions & Advisories
Enhanced CRM Training
Recommendations were made to improve Crew Resource Management, specifically addressing the authority gradient between senior captains and junior first officers.
Spatial Disorientation Awareness
Increased emphasis on training for 'dark hole' takeoffs where lack of ground lighting can lead to sensory illusions.
Known Controversies & Unanswered Questions
Disagreement on Probable Cause
Reference ↗The Egyptian Ministry of Civil Aviation (MCA) did not conclude a definitive cause, while the American NTSB and French BEA issued separate comments attributing the crash to pilot spatial disorientation and lack of CRM.