Overview
On December 20th, 2021, an Emirates Boeing 777-300ER, registration A6-EQI, operating flight EK-231 from Dubai International Airport (DXB) to Washington Dulles International Airport (IAD), overran the runway on takeoff from runway 30R. The aircraft became airborne at the very end of the runway safety area and continued to Washington, where it landed without further incident.
Key Details
• Aircraft:
• Type: Boeing 777-300ER
• Registration: A6-EQI
• Engines: GE90
• Operator: Emirates Airlines
• Flight Information:
• Flight Number: EK-231
• Route: Dubai (DXB) to Washington Dulles (IAD)
• Date: December 20th, 2021
• Persons on Board: 354 passengers and 18 crew
Sequence of Events
1. Preflight Preparation:
• The commander (pilot flying) noticed the altitude selector on the Mode Control Panel (MCP) was set to 0000 feet.
• The commander adjusted the setting to 4,000 feet, aligning with the SENPA 2F Standard Instrument Departure (SID).
2. Takeoff Roll:
• The aircraft exceeded 216 knots over ground within 4,400 meters (14,400 feet) of runway 30R.
• The aircraft achieved lift-off only 90 meters short of the localizer antennas, exiting the runway end safety area at 234 knots.
3. Climb Performance:
• The flight director’s ALT mode caused incorrect pitch commands, leading to a shallow climb rate of approximately 800 feet per minute.
• The crew selected TOGA mode, which restored correct flight director commands and climb performance.
4. Continued Operation:
• Despite initial challenges, the flight proceeded uneventfully to Washington.
• The aircraft was grounded for four days upon its return to Dubai for inspection.
Investigation Findings
Probable Cause:
The incorrect activation of the autopilot flight director system (AFDS) in ALT mode, resulting in inappropriate pitch commands during the takeoff phase.
Contributing Factors:
1. System Design:
• The AFDS defaulted to ALT mode when the MCP altitude was within 20 feet of the airport elevation.
• No safeguards prevented takeoff with this incorrect setting.
2. Crew Actions:
• The commander failed to recognize the inappropriate flight director commands.
• The copilot, though aware, did not address the issue effectively.
3. Pressure to Perform:
• The commander may have been distracted or influenced by operational pressures to maintain an on-time departure.
4. Procedural Gaps:
• Emirates’ Flight Crew Operations Manual (FCOM) lacked explicit guidance on resetting flight director modes during takeoff preparation.
Safety Measures and Recommendations
1. Crew Alerts and Training:
• Emirates issued Crew Alerts reminding pilots not to set MCP altitude to airport elevation after landing or shutdown.
• Enhanced training for identifying and rectifying inappropriate flight director commands.
2. FCOM Updates:
• Inclusion of explicit instructions for resetting flight director modes during preflight checks.
3. System Design Review:
• Recommendations to Boeing for incorporating safeguards against inappropriate AFDS settings during critical flight phases.
Metar Weather Observations
• Weather at the time of the incident indicated calm conditions with light variable winds and no significant weather changes (CAVOK).
Conclusion
This incident underscores the importance of strict adherence to preflight procedures and highlights potential design limitations in automation systems. The corrective actions taken by Emirates aim to address both procedural and training deficiencies, ensuring the safety of future operations.
Disclaimer
This report is based on available information as of January 17th, 2025. If you are the rightful owner of any associated media or details and wish for them to be removed, please contact takedown@cockpitking.com.
