The 52nd and final Lockheed Martin C-5M Super Galaxy was delivered to the USAF on August 2, bringing to a close a comprehensive life-extension program for the venerable airlifter.
The Reliability Enhancement and Re-engining Program (RERP) was designed to extend the life of in-service C-5B until the 2040s, and involved 70 major modifications or upgrades of the aircraft’s airframe structure, environmental and pneumatic systems, hydraulic systems, electrical system, fuel system, landing gear, and flight controls.
Arguably the biggest upgrade was the replacement with the original GE TF39 engines with more modern, more powerful and more efficient GE F138s, the military designation of the commercial GE CF6-80C2L1F which is rated at 60,000lb thrust. For the C-5M, the F138 is de-rated to 50,000lbs but still provides 22 per cent more thrust than the TF39, while also allowing the C-5M to meet FAA Stage 4 noise reduction requirements.
Fifty C-5Bs were manufactured in the 1980s as a follow-up build run to the original run of 83 C-5As which were built in the late 1960s and early 1970s. The final C-5A was retired in November 2017, although two were modified to a specialised C-5C standard for the transport of outsized payloads such as military satellites, and these were also upgraded to C-5M standard under the RERP program.
The RERP program commenced in 2006 and followed the C-5 avionic modernization program (AMP) which ran from 1998 to 2002 and which saw the fleet fitted with Global Air Traffic Management compliant systems including improved communications and navigation equipment, new flat panel displays, and a new autopilot system.
The C-5M holds 89 FAI-certified world aviation records, more than any other aircraft type, including time-to-climb with payload, altitude with payload, and greatest payload carried.