aMilitary designations shown. Designations in parentheses are commercial engine equivalents where they exist.
bEntries corrected after release of the January 31, 2007, prepublication version of the report. An entry for the C-17 was also deleted at that time.
Nonrecurring costs include any costs of the research and development (R&D), testing and evaluation efforts associated with airframe modification, engine modification, nacelle redesign, pylon redesign, other subsystems redesign, flight testing, weapons separation design efforts related to new tooling requirements, and all systems engineering and program management by contractors and the government.
The recurring costs would include the unit cost of new engines, of installation kits (engine and airframe modifications), of logistical support, of training, tooling, and test equipment, of spares, data, etc.
Costs and Benefits to Operations and Support
The benefits to operations and support (O&S) would include the impact of fuel savings attributed to more fuel-efficient engines. They also include the impact of improvements in engine reliability and maintainability on cost of mission maintenance personnel, consumables, depot-level reparables (DLRs), and engine overhaul. These elements are defined by the Cost Analysis Improvement Group (CAIG) in the Office of the Secretary of Defense (OSD) as follows:
Maintenance personnel cost reflects the pay and allowances of military and civilian personnel who support and perform maintenance on the engine. Depending on the maintenance concept and the organizational structure, this element will include maintenance personnel at the organizational level and, possibly, the intermediate level.
Consumables are materials and bits-and-pieces repair parts that are used up or consumed during maintenance.
DLRs are the unit-level cost of reimbursing the stock fund for purchases of the DLR spares (also referred to as exchangeables) used to replace initial stocks. DLRs may include repairable