Depot Maintenance (Non-IF)

The Depot Maintenance (NON-IF) Program Element (PE 0702207N) is a Navy Research, Development, Test & Evaluation (RDT&E) initiative focused on extending the operational life of critical naval aviation platforms through Service Life Assessment Programs (SLAP) and related engineering efforts. The primary objective of this program is to assess and address the structural and subsystem conditions of the F/A-18, EA-18G, T-45, and MH-60 aircraft fleets. This ensures these platforms can safely and effectively meet Chief of Naval Operations (CNO) inventory requirements until their planned end-of-service dates. The program supports the development of technical data, engineering change proposals, and modification strategies necessary for follow-on Service Life Extension Programs (SLEP).

The F/A-18 and EA-18G SLAP aims to determine the modifications required to extend the design life limits of the F/A-18E/F and EA-18G aircraft. The current service life limits for these aircraft are insufficient to meet Navy inventory needs, especially as the transition to the Joint Strike Fighter continues. The SLAP effort includes detailed structural investigations, such as main landing gear, wings, and fuselage, and subsystem assessments including hydraulics, wiring, and actuators. The program's goals are to increase service life and operational cycles, with assessments conducted through stress and fatigue analysis, finite element modeling, and aircraft teardown to validate findings and inform future SLEP modifications.

The T-45 SLAP focuses on extending the service life of the T-45 training aircraft. The program seeks to increase the current flight hour limit, supporting the Navy's Instructor Pilot Production and Naval Flight Officer Training Requirements through 2035. The T-45 SLAP includes a comprehensive assessment of critical subsystems, requiring further analysis, teardown, recertification, and testing. Funding supports the production contract for subsystem SLAP, engineering labor, and technical support at Fleet Readiness Center Southeast and NAWCAD Patuxent River. The objective is to ensure all critical subsystems can support extended usage and to develop redesigns or improvements where necessary.

The MH-60 SLAP is designed to evaluate and extend the service life of the MH-60S and MH-60R helicopter fleets, which are critical to multiple Navy missions including Combat Logistics, Surface Warfare, Combat Search and Rescue, and Airborne Mine Countermeasures. The MH-60S fleet is expected to reach its design life limit as early as 2027, and the MH-60R by 2034. The SLAP effort consists of investigative inspections and forward-looking analyses of both airframe structures, such as cockpit beams, gearbox frames, and landing gear, and subsystems including wiring, engines, and avionics. The findings will inform the technical requirements for a phased SLEP, ensuring continued operational availability until the transition to Future Vertical Lift-Maritime Strike platforms.

Each of these SLAP projects employs a combination of sole-source contracts with the respective aircraft prime manufacturers, as well as government engineering and logistics support from Naval Air Systems Command, NAWCAD Patuxent River, and various Fleet Readiness Centers. The assessments use structural fatigue testing, fleet usage data, and advanced modeling tools to identify life-limiting factors and develop actionable engineering solutions. The ultimate goal is to avoid inventory shortfalls and maintain mission readiness by safely extending aircraft service lives.

The Depot Maintenance (NON-IF) Program is justified under the Operational Systems Development budget activity because it supports the development and upgrade of fielded systems, ensuring they remain viable and effective in the fleet. Funding adjustments in FY 2026 reflect increased requirements for subsystem analysis and production contracts, particularly for the T-45, as well as efficiencies gained in the F/A-18 and EA-18G efforts due to commonality and reduced analysis needs. The program is structured to provide the engineering foundation for future SLEP efforts, which will be essential for bridging capability gaps until next-generation platforms are fully fielded.