The first of 52 US Air Force C-5 Galaxy strategic transport aircraft has entered the reliability enhancement and re-engining programme (RERP) phase of modifications.

The Galaxy is US air force’s largest airlifter and can carry a cargo payload of six mine-resistant ambush-protected vehicles (MRAPs) or up to five helicopters as well as troops.

The RERP modifications, conducted by Lockheed Martin, involve over 70 improvements and upgrades to the C-5 airframe and aircraft systems including the installation of new higher-thrust, more reliable GE F138-GE-100 turbofan engines replacing the existing GE TF39s.

The RERP will also include work on wing and wing components, cargo compartment, flight station and landing gear and aircraft systems.

The modified transport aircraft called the C-5M Super Galaxy will be able to climb higher and faster than current C5s while carrying more cargo over longer distances and requiring less tanker support.

The RERP is the second phase of the two part modernisation programme, the first phase of which was avionics modernisation, which has been completed on half of the C-5 fleet.

Lockheed will deliver 52 C-5Ms that will consist of modifications on 49 C-5Bs, two C-5Cs, and one C-5A by 2016. Lockheed and the USAF will then perform functional check flights of the Super Galaxy before its scheduled redelivery.

The first production C-5M is scheduled for redelivery to Dover AFB in September 2010.

Two of the three C-5M test fleet has already been delivered to USAF.