The U.S. Air Force has recently received the first production version of the C-5M transport. This is a refurbishment program for 52 of its 111 C-5 transports. Earlier, three C-5s were converted to the C-5M standard and tested. The upgrades (new engines, cockpit and electronics) proved to be successful. The refurbishment costs nearly $100 million per aircraft. The new engines are cheaper to operate, and quieter (max sound is 105 decibels, versus 120 with the old engines.) The new cockpit and electronics make the aircraft easier and safer to operate. The C-5Ms are expected to operate until the 2030s.
The C-5 entered service in 1970. It is a 380 ton aircraft that can carry up to 122 tons (but usually carries 100 tons or less, to reduce metal fatigue.) Max speed is 930 kilometers an hour. It can fly 4,400 kilometers on internal fuel, and can refuel in the air. The C-5M refurbishment program will be completed in six years, and the updated aircraft should be able to operate for another three decades.