NAVAL AIR STATION NORTH ISLAND, Calif. –
Ordinarily recognized for its maintenance, repair and overhaul (MRO) work on naval aircraft, Fleet Readiness Center Southwest (FRCSW) also stands out as the Navy’s sole provider of MRO services to the gas turbine LM2500 engine.
For more than 45 years, FRCSW has worked on the two types of LM2500: single and twin shank, and low power turbine.
Production of the LM2500 began in 1969 by the General Electric Co. The engines were first used by the Navy to power Spruance and Kidd-class destroyers in the 1970s. A decade later, installation of the reliable engines expanded to include Oliver Hazard Perry-class frigates, Ticonderoga-class cruisers and Arleigh Burke-class destroyers.
The engines also power oil platforms and pipeline pumping stations.
About 20 FRCSW artisans that include mechanics and machinists handle the engine’s MRO requirements.
Unlike many aircraft platforms serviced at FRCSW, the LM2500 engines are not serviced under a planned maintenance interval. Instead, they are repaired for significant cause.
Many engines are overhauled because of degradation of the turbine blades and turbine nozzles. Excessive wear of the components is indicated by power loss and increased fuel consumption.
A typical engine overhaul requires about 3,000 man-hours.
During overhaul, engines are disassembled to their subassemblies that are comprised of nine components including two gearboxes, stator cases, the compressor and high pressure turbine nozzle.
Rebuilding of the engine’s compressor is key to a successful overhaul. The compressor is rebuilt in five stages, starting with the rear shaft. The component must be in strict specification, otherwise the engine can suffer potential vibrations, causing a rejection during the quality assurance portion of the overhaul process.
Approximately one-third of the MRO procedures to the engine are handled by the manufacturing program in Building 472 where cleaning, metal spray and non-destructive inspections are performed.
Meanwhile, in the fuel components shop in Building 379, pneudraulics systems mechanics test, repair and maintain LM2500 hydraulic and pneumatic systems and components that regulate fluid flow.
Four years ago, FRCSW installed a new vacuum furnace in Building 379 designed to “stress test” LM2500 parts. The custom-built, $1.9 million furnace may accommodate engine components up to 60 inches in height and diameter.
In addition to overhauls, the shop also handles service requests that cannot be completed in the fleet.
FRCSW customers include Naval Sea Systems Command (NAVSEA) and foreign navies.
The command’s LM2500 program schedules 15 to 20 engine overhauls annually.