CHARLESTON AIR FORCE BASE, S.C. –
When the strength of aircraft metals failed recently, Charleston AFB structural and metals technology maintainers seized a chance to show their determination and teamwork was stronger.
The opportunity resulted from an overseas mission, involving the loading of a helicopter into a Charleston-based C-17, where a crack was sustained in the airplane's cargo floor.
Repairing a large crack in the floor of a C-17 isn't the normal sort of task the maintainers at Charleston encounter, especially when the crack occurs in the vicinity of a load bearing tie down ring, which is designed to secure heavy cargo onboard, said Kim Patterson, an element chief with the 437th Maintenance Squadron structural maintenance shop.
Tyrone Venning, a structural maintenance technician with the 437 MXS who works with Mr. Patterson, was one of four maintainers assigned to remove the damaged section and reinstall a new section of cargo flooring, milled from a solid block of raw, unformed aluminum by Charleston's metals technology shop.
Just finishing up a four-day stint of 12-hour shifts to complete a different task, Mr. Venning was a bit worn out when he was assigned to the job, but said after being "in the zone", there was no stopping him.
"Structural maintainers like a challenge," he said. "Sometimes we get a lot of smaller jobs, so when something like this comes along, we like it."
The removal of the damaged flooring section was only the first step in a tedious repair process. To replace the five-inch-thick piece being removed, a precise match was required.
Producing an identical section of flooring from raw metal was a challenge to be approached with caution, said Tech. Sgt. Stephen Sarkany, the swing shift supervisor for the 437 MXS metals technology shop. When working with metal, one false move can cause the entire project to be scrapped, he said.
"Nothing's simple when you are working with aircraft," he said. "Even figuring out ways to clamp down the piece you are working on is a challenge."
Sergeant Sarkany didn't waste any time after receiving word about the damaged floor section. Before the official work order was even placed, he got right down to business creating a computerized, three-dimensional design of a new piece from paper, two-dimensional mechanical drawings.
By the time the decision was made to move forward with the fabrication, initial drafts for the part were already completed, he said.
The process of turning a orindary hunk of aluminum into a useful C-17 aircraft component began by using a cutting machine that produces a powerful jet of water firing from between 20,000 to 30,000 pounds per square inch, slicing through anything in its path.
After a rough shape was formed, the next portion of metalwork was accomplished on a machine using various sizes of drill bits to mill a desired shape into the metal. By using a series of passes across the surface of the metal, a usable object slowly emerges.
The process is painstaking, but Sergeant Sarkany said his job is very rewarding.
"I like to make things," he said. "I think I have the best job in the Air Force. I told one of our commanders that a couple years ago, and he said, 'No, I have the best job in the Air Force.'"
Out of respect, Sergeant Sarkany said he wasn't one to disagree.
While the maintainers in the metals technology shop were busy constructing the new part, the structural maintenance section was hard at work in the base corrosion control hangar removing the old section of the cargo floor.
From the surface, the damage looked illusively simple to repair, said Mr. Venning, but one look under the deck offered a whole new perspective. The piece was actually part of a single continuous rail running from the front of the plane to the back.
"The angles we had to cut at were really difficult. Just trying to get your hands into the right place was hard," he said. "We couldn't tell what we were cutting in some places, so we slid pieces of stainless steel between overlapping aluminum, and when we saw sparks from the steel, we knew we had cut far enough."
More than 20 custom-fit pieces of sheet metal were fabricated to secure the newly manufactured section of flooring in place. Pieced together around its edges, they formed an exterior skeletal structure mating it perfectly into place.
The complete repair process was finished in record time, two hours ahead of schedule, said Mr. Venning, and the entire job went amazingly well. He said the success of the job revolved around the skill, patience and dedication of all the maintainers involved from start to finish.
"What these guys did wasn't short of miraculous," said Tech. Sgt. Robert Pellam, a quality assurance inspector with the 437th Maintenance Group. "It was impressive."
Sergeant Pellam was assigned to the structural maintenance shop prior to holding a QA position, and Mr. Venning said he is an expert in structural repairs.
"There's no fooling Sergeant Pellam," he said.
With a total cost of more than 200 man-hours and $15,000, the damage came with a price tag, and it is a lesson to always remain vigilant in one's work, said Mr. Venning.
"If people could see the kind of work we go though to repair something that for them seems small, they might try to be more careful," he said.