Flight Background
On 24 April 2004, a Boeing 747-132, registration N481EV, departed from Ramstein Airport in Germany at 0905 hrs on a cargo flight to Wright Field in New York State. The aircraft was powered by four Pratt & Whitney JT9D-7F turbofan engines. The crew consisted of two pilots and a flight engineer, with a second flight engineer carried as a passenger. The aircraft's gross mass was 290 tonnes. The weather was clear with no forecast precipitation.
Engine Failure
Shortly after reaching cruising level FL360, the crew noticed an anomaly on the Engine Instrument Display System (EIDS). The No 1 engine (left outboard) Engine Pressure Ratio (EPR) began to reduce, and the fuel flow increased. The commander instructed the flight engineer to check the engine indications, which confirmed the engine had failed. The engine shutdown drill was performed per the abnormal checklist. The London Area Control Centre (LACC) was informed, and a descent to FL310 was requested and approved.
Descent and Attempted Restart
At FL310, the flight engineer attempted to restart the No 1 engine, but it was unsuccessful. The flight engineer then contacted the operator's Maintenance Control, who advised returning to Ramstein. A 180° left turn was approved with a descent to FL210. During the descent, the commander noticed the thrust levers were well forward of the normal position for the descent, yet the EPR indications were at idle.
Low Thrust Issue
After leveling at FL210, the airspeed began to decrease significantly. The crew recorded the engine EPRs: No 1 at 0.704, No 2 at 1.124, No 3 at 1.206, and No 4 at 1.149. The commander asked the flight engineer to check igniters and fuel heat, which were normal. Maintenance Control offered no solutions. The crew agreed that if normal thrust were not available, an immediate diversion to London Heathrow was the safest option.
Diversion and Approach
The crew declared an emergency and requested diversion to Heathrow. Transponder code 7700 was set. The commander advanced the No 2 and No 4 thrust levers, but EPRs remained unchanged while EGTs increased to approximately 890°C. The commander decided to manage the descent visually. The aircraft was radar vectored, and although initially high for the approach, the crew performed S-turns and a 270° right turn to lose height. The approach charts for Heathrow were not available, so the ILS frequency for Runway 27R and its length were obtained from ATC.
Landing
The commander used turning maneuvers, flap, and gear selections to control speed and height. In the final stages with flaps at 30°, thrust was added and the engines responded. The aircraft touched down at 145 kt CAS within the normal touchdown zone. Medium autobrake, spoilers, and reverse thrust were used. After a discussion with airport rescue and fire services, the aircraft taxied under its own power to a parking stand. No damage occurred, and no injuries were reported.