ERA13IA006

While maneuvering at 3,000 feet over the Atlantic Ocean, three of the airplane's four engines experienced compressor stalls and associated tailpipe fires. The flight crew was able to extinguish the three tailpipe fires and eventually restart the three engines. The airplane subsequently proceeded to its departure airport and landed uneventfully. Postaccident examination of the airplane revealed extreme salt buildup in all four engines. After the salt was rinsed away with water, the engine efficiencies improved greatly and no other anomalies were noted.

On February 09, 2007 at 2212 universal time coordinated (UTC), a Lockheed WP-3D Orion, N42RF, registered to and operated by the National Oceanic and Atmospheric Administration (NOAA), experienced a loss of power on three of the four engines while maneuvering over the Atlantic Ocean 540 nautical miles east of St. John’s International Airport (CYYT), St. John’s, Newfoundland, Canada. Night instrument meteorological conditions prevailed, and an instrument flight rules flight plan had been filed for the public use. The airplane was not damaged and there were no injuries to the airline transport pilot aircraft commander (AC), co-pilot (CP), flight engineer (FE), or three other crew members. The flight originated from CYYT at 1823 UTC.

The incident was investigated by the National Oceanic and Atmospheric Administration and they reported their findings to NTSB. A copy of the NOAA report is contained in the NTSB docket for this incident.

According to the AC, the majority of the flight was flown at 3000 feet mean sea level (msl) and below. About 2212 UTC, while flying over the Atlantic Ocean, the crew in the rear of the airplane declared a fire on the No. 3 engine while the cockpit crew simultaneously heard "popping" sounds. The AC ordered the shutdown of the No. 3 engine. The CP was completing the emergency checklist, when the aft crewmembers observed flames coming from the No. 4 engine, and the AC directed the shutdown of the No. 4 engine.

About 5 minutes later, the aft crewmembers announced "fire on No. 1." The AC and FE noted a power loss and turbine inlet over-temperature on the No. 1 engine, without the associated fire light and warning horn. The AC directed the FE to pull back power on the No. 1 engine in an attempt to extinguish the flames. Believing that he heard the order to shut down the No. 1 engine, the FE pulled the emergency shutdown handle for the No. 1 engine. While operating single engine at 800 feet msl and 140 knots, the AC called for the immediate restart of the No. 1 engine. With the successful restart of the No. 1 engine, the airplane began a slow climb on two engines. The Nos. 3 and 4 engines were then successfully restarted, and the flight climbed to 14,000 feet msl. The flight ultimately landed uneventfully at CYYT.

Post-flight inspection of the airplane by NOAA personnel revealed significant salt buildup on all engine intakes, and first stage compressors. The No. 2 engine appeared to exhibit the most buildup of the four engines. The airplane fuselage and windows were also heavily covered with salt.

The next morning, engine efficiency tests were conducted on the engines. This was a process in which the engines are run at high and low power for an allotted amount of time. The results from the tests revealed the engines at the following efficiencies:

Engine No. 1 – 87 percent

Engine No. 2 – 88.9 percent

Engine No. 3 – 90.3 percent

Engine No. 4 – 91.3 percent

This represented a drop in performance as the engines were normally in the 98 to 102 percent range. The engines were then rinsed and engine efficiency tests were conducted again with the following results:

Engine No. 1 – 102.1 percent

Engine No. 2 – 104.9 percent

Engine No. 3 – 101.7 percent

Engine No. 4 – 103.1 percent