US AFRL addresses C-5 aircraft cracking issues


C-5 Galaxy aircraft


US Air Force Research Laboratory (AFRL) engineers have developed new structural technologies to solve the cracking and corrosion issues related with the Lockheed Martin-built C-5 Galaxy cargo aircraft, in a bid to expand its serviceability.

Under the Durable C-5 Structural Improvements Program, a more stress and corrosion-resistant aluminium alloy and a new die forging process has been developed to eliminate the cracks at the C-5 cargo floor's bulkhead end fittings, which restricted its cargo carrying capabilities to a maximum of 80%.

According to the AFRL, the new procedures will help in the development of all 92 fitting shapes required for the C-5 bulkhead floor, using only two separate forging dies.

The reshaped end fittings provide an optimised design that is less prone to cracks, and also offers multiple benefits for the revamped C-5 aircraft, which includes a 25% overall cost savings, an 80% reduction in fabrication time, and a 60% increase in service life of the fittings.

A number of C-5 Galaxy aircraft were recently equipped with the new structural fittings at the Warner Robins Air Logistics Center in Georgia, US.

The traditional methods employed earlier for repairing proved to be insufficient, as the replacement fittings provided to the aircraft often cracked during the machining process, and also had a shorter lifespan than the original parts.

The AFRL is also planning to apply the forging process to other aircraft that experience similar cracking problems.

The C-5 Galaxy is a large military transport aircraft built with a heavy intercontinental-range strategic airlift capability, to carry oversize cargos, including all 100% air-certifiable cargo.

Since 1970, the airlifter served as the global direct delivery weapons system for the US.


Image: The C-5 Galaxy is equipped with new structural fittings to increase its cargo carrying capability. Photo: courtesy of AFRL.