By Brian Brackens, Air Force Life Cycle Management Center / Published September 01, 2020
ROBINS AIR FORCE BASE, Ga. (AFLCMC) – Ensuring the Air Force’s largest plane is able to operate for years to come isn’t a small feat, but the Air Force Life Cycle Management Center’s C-5M Super Galaxy Program Office is successfully leading efforts to keep the plane relevant and in the fight.
Standing as tall as a six story building, nearly the length of a football field, and with a maximum takeoff weight of close to a million pounds, the C-5M Super Galaxy is massive, and plays an important role in operations around the world.
“The C-5 transports cargo and personnel for the entire U.S. Department of Defense,” said Janet Maddox, chief of the program office, and leader of a 300 person team responsible for the aircraft. “It can be emergency relief supplies, firetrucks, airplanes, vehicles, you name it, the C-5 has probably carried it at some point.”
In addition to supporting DOD operations, the C-5 also supports other federal agencies to include NASA, and has carried satellites, the Hubble Space Telescope and parts of the International Space Station.
So far, in Fiscal Year 2020, the C-5 fleet has flown more than 32,103 hours, 7,074 sorties, and 4,157 missions.
With a service life up through 2040, the fleet has a lot of miles left, and the program office is working a number of structural and mechanical modifications to keep it in flight.
Some of the work includes the BATMAN Fitting repair which ensures adequate structural strength in the tail section. This work is being accomplished on the entire C-5 Fleet and is expected to be complete by next year.
“This important repair ensures the C-5 will continue to fly safely for many years to come. The BATMAN fitting is so named due to the fittings appearance of the BATMAN character with arms and cloak extended…cool, huh?” said Clay Elliott, a C-5 Structures subject matter expert.
Additional modifications include the Pylon-to-Wing Interface (PWI) structural reinforcement to maintain necessary strength where the engine pylons attach to the wing, and upgrading defensive mechanisms and avionics components throughout the aircraft. These modifications allow the C-5 to operate in contested environments, ensuring its continued Global Reach.
Additive manufacturing (AM), more commonly known as 3D printing, is also playing a role in sustaining the fleet and cutting costs.
“We currently have 133 parts flying in the fleet that were made from additive manufacturing, to include panels, and handles,” said Maddox. “We are continuing to evaluate expanding that list to include more parts if we can.”
A great example of the benefits of additive manufacturing is the Ramp Bell Crank Assembly. The Air Force has been unable to find a supplier to produce the part and has been pulling replacements from retired aircraft when the part fails. With this supply almost depleted, the Air Force was able to use additive manufacturing to produce replacements in only two weeks and at a lower cost.
Another example is the C-5 pressure door handle.
“The C-5 pressure door handle is expensive, for what it is: basically a small bar of metal with a bolt in the middle of it that it pivots around,” said Matthew Harvey, C-5 structures engineer and AM lead. “A redesign of the legacy 4F41290-103A handle using additive manufacturing with an aluminum alloy generated around a nearly 95 percent cost savings for the Air Force.”
The program office is also working an initiative with the Georgia Tech Research Institute and the Rapid Sustainment Office to implement Conditions Based Maintenance Plus (CBM+) to predict when aircraft parts are going to fail so that they can be replaced prior to failure.
The main goal of CBM+ is to eliminate unscheduled maintenance, therefore ensuring aircraft are available to meet the flying schedule.
The Air Force is learning from Delta Airline’s 10-year CBM+ journey.
The C-5 Program Office developed sensor-based algorithms for the Engine Bleed Air System, Air Cycle Refrigeration System, and the Thrust Reversers that drove 14 predictive maintenance actions, thereby avoiding unscheduled breaks. Although this effort remains in the very early stages of implementation, it will fundamentally change the C-5 maintenance response and reliability posture in the future.
“The C-5 mission is an important one, and it doesn’t happen without the hard work of our personnel across the enterprise,” Maddox said. “The C-5 is unique and it’s a small fleet of only 52 aircraft. Everything we do is all about keeping the aircraft capable, affordable, safe, and flying.”