Case Studies

How to Tune a High-Performance Jet Engine

by Alan Joch

November 2015

Performing core maintenance, repair, and overhaul (MRO) services on precision aircraft engines while also gathering important data for continuous improvements to engine designs begins with dismantling the engines. From there, it takes highly skilled technicians with years of experience just to determine which maintenance procedures are required when an engine arrives for service.


IHI Corporation

Location: Tokyo, Japan

Industry: Civilian and military aerospace and heavy equipment manufacturing, servicing, and repair

Employees: 27,562

Revenue: ¥1,455,844 million in FY 2014

Oracle products: Oracle Complex Maintenance, Repair, and Overhaul; Oracle E-Business Suite

Masa Yamashita

Director, Maintenance Division, Aero Engine and Space Operations

Length of tenure: 27 years

Education: Master’s degree in mechanical engineering, University of Tokyo


“When we receive an engine, we disassemble, clean, and closely inspect it to understand what it needs to perform reliably and safely once it returns to service,” says Masa Yamashita, director of IHI’s Maintenance Division, Aero Engine and Space Operations.

IHI Corporation

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Wear and tear of engine parts differs depending on a number of factors. For example, the life span of components is shorter when they’re used on short-haul routes with numerous takeoffs and landings, or on routes with harsh climates and high pollution levels.

The service staff pays particular attention to components known as life-limited parts, or LLPs. These units include rotating compressor and turbine hubs, shafts, and disks that must be replaced once they’ve operated for a set number of cycles/hours. Tracking and controlling LLPs is essential to ensure safety and regulatory compliance. The tracking data also helps IHI and engine manu-facturers calculate future demand for replacements and ongoing engine lifecycle costs. “LLP calculations yield important insights that help us understand the rate at which these types of parts degrade,” says Tsuyoshi Tagaya, general manager of IHI’s Civil Aero Engine Business Strategy Group, Aero Engine and Space Operations. “These are important considerations for making financial calculations.”

IHI staffers also check for relevant service bulletins and airworthiness directives to bring the engine in line with the latest performance requirements. Service technicians then document each step from when an engine arrives for service to when it’s returned to the fleet. “Sometimes, even 5 years or 10 years after we perform maintenance,” Tagaya says, “a customer asks us for detailed information if questions arise about the aircraft.”

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