NEW CASTLE AIR NATIONAL GUARD BASE, Del. – The fuel system of a C-130H2 is one of the most complex and critical systems on the aircraft. To keep the aircraft mission-ready, fuel cell maintainers work in dark, grimy and difficult-to-access places. They perch on top of the wings while clipped to a safety harness, or inside the tanks wearing a full-face respirator.
Working on an aircraft fuel system poses many risks. Jet fuel and its fumes are highly toxic and combustible. Though fuel is pumped out before maintainers enter the tanks, noxious vapors can displace oxygen, so respirators must be donned and safety protocols strictly followed. There is also a risk of getting injured or trapped inside the tank, which is a very confined space. Brackets and other structural components become obstacles, and there is a very real potential for injury.
“The first thing I ask anyone who is interested in working in the fuel cell is, ‘Are you claustrophobic or afraid of high places?’” said Master Sgt. Eugene Jackson, 166th Maintenance Squadron aircraft fuel systems repair section supervisor. “If they say ‘yes’ to either, they’re not suited to this job. Most of our training is hands-on. Until you actually go in tank and get eyes on the components and see what you actually have to do to gain access to the components, you won’t be able to perform the job efficiently.”
Finally, there are environmental considerations.
“We see more fuel venting from wings in the summer and more leaks from access doors and fasteners in the winter,” explained Jackson.
Venting issues are common in the summer due to rapid expansion of the fuel in a warm environment. If the tank is full during a cool summer morning, there’s the potential for fuel venting when the ambient temperature increases later in the day.
“Conversely, access doors will leak as seals can stiffen and shrink when the weather gets cold,” said Jackson. “To fix those issues, we’ll either change out the door seals or repair any sealant that might be behind the access door.”
Besides sealing leaky tanks, maintainers remove and replace boost pumps (which supply fuel to the engines), dump pumps (which expel fuel from the aircraft in emergency situations), various valves, pressure switches, manifolds, access doors, bladder cells and other components. They also assist Guidance and Control (GAC) with wiring harnesses for probes and compensators for the fuel quantity system.
“Our fuel cell technicians are one of the finest examples of the silent unsung heroes that keep these machines flying. The fuel cell technicians of the 166th Maintenance Squadron are the best in the business,” said Col. William Roche, 166th Maintenance Group commander.
Technical training, proficiency in rescue procedures and attention to detail are requisite for safe fuel cell maintenance. The Airmen of the 166th Maintenance Squadron do what it takes to keep C-130H2s airworthy, safe and ready to complete the mission.