What happened
On July 7, 2007, a Boeing 767-432-ER, registration N834MH, was scheduled for a flight from Rome Fiumicino to Atlanta. Following technical delays, the aircraft commenced its takeoff roll for runway 16R at approximately 15:24 UTC. During the acceleration phase, specifically near V1 speed, the aircraft ingested approximately 30 young seagulls into both engines.
Shortly after takeoff, the crew observed excessive vibration levels on both engines, with the right engine also showing elevated temperatures. The commander decided to execute an immediate return to the airport. To ensure a safe landing weight, the crew performed a fuel dump at 4,000 feet. The aircraft landed at Rome Fiumicino at 15:37 UTC. The landing was performed at an overweight condition, with the aircraft mass at 427,000 lbs, significantly exceeding the maximum landing mass of 350,000 lbs. During deceleration, the left thrust reverser failed to operate, leading to heavy brake usage and subsequent brake overheating, which required cooling by emergency services.
The investigation
The ANSV investigation examined the flight data recorder, cockpit voice recorder, and physical wreckage. The inspection of the engines revealed damage to the fan blades, fan cases, and nose cowls on both powerplants. The investigation also reviewed airport bird control procedures and the crew's observations of wildlife prior to takeoff. Notably, the co-pilot had observed a large number of gulls near the taxiway and suggested clearing the runway, but the takeoff proceeded immediately after the controller re-issued the takeoff clearance.
Findings
- The primary cause of the event was a bird strike involving the ingestion of approximately 30 gulls into both engines.
- The crew underestimated the risk posed by the visible presence of numerous birds near the departure runway.
- Inadequacies were identified in the bird prevention and habitat management systems at Rome Fiumicino, specifically regarding the management of standing water and drainage areas that attract wildlife.
- There were deficiencies in the airport's bird control and prevention measures.