167th Airlift Wing’s aircraft structural maintenance shop marks milestone with field repair of C-5A’s crown skin

Published May 7, 2013
By Staff Sgt. Sherree Grebenstein
167AW/PA

MARTINSBURG, W.Va. -- The 167th Airlift Wing's aircraft structural maintenance shop is undertaking the painstaking repair of two panels on the upper fuselage crown skin of aircraft 68-0212 and marking a milestone in the process.
According to Chuck LaFaver, a field representative with Lockheed Martin assigned to the 167th AW, this is the first time a field unit has replaced the crown skin of a C-5 aircraft.
Normally those types of repairs are done at depot level.
But Master Sgt. Brad Teter, shop chief of the wing's aircraft structural maintenance shop, said Airmen assigned to the wing could do it in less time and that they were up to the challenge.
During a magneto optical imaging inspection (MOI) - a part of the major isochronal inspection (ISO) at Dover Air Force Base this spring - inspectors found a number of cracks in the C-5A's crown skin on 68-0212. The aircraft's skin which is normally 0.047 inches thick is designed to keep the C-5 pressurized during flight.
"Dover AFB determined that the cracks were so severe (that engineering assistance was needed)," Teter said.
Engineers from Robins Air Force Base in Warner Robins, Ga., determined last month that before the aircraft could be put back into service two 48 x 96 inch panels would need to be replaced.
"To our knowledge the process that we are doing has never been done in the field," Teter explained. "It's a depot-level repair."
Officials at Dover Air Force Base estimated it would take 30 to 35 days to replace the two panels.
"Due to time, they really didn't want to do this job so we said that we would do it at home station because it is our aircraft," Teter noted.
"The biggest problem that we had is trying to find the material to do the job," he said.
Teter said his shop was able to secure six sheets of material - 7475-T761 material - from the depot facility in Warner Robins, Ga.
"The material is on its way here," he noted. "We are in the process of taking the old (panels) off right now."
Teter believes the wing's Airmen can do the job in 15 days.
Work on the project is being done 24/7 with two airmen assigned during each of the three shifts. Airmen working on the project were handpicked due to their expertise.
"It's very precise. A lot of close tolerances," he noted of the work.
Translation: "Nothing can be sloppy." All of the holes in the panel must be precise in diameter.
"You can't have any slop to speak of in any of the holes. It's just a very tedious process," Teter said. "The airplane is unserviceable until these skins are changed out. When the airplane is unserviceable we can't supply materials to the warfighter down range."
Adding: "This is not a job that you train somebody on. You need to utilize your very skilled technicians on this particular job."
Whether on the phone or attending conference calls, Teter deals with the engineers in Warner Robins, Ga., on a daily basis due to the job's intricate nature,
"The phone lines are very hot," he said with a smile.
Teter said the ability to do this type of high-level maintenance work on an aircraft "in house" reflects the skills mastered by the wing's aircraft structural maintainers.
"It shows how far we have come in the last five years since the C-5 conversion to where we are today. Actually doing depot-level maintenance in the field," he noted.
Adding: "It shows the level of people that we have retained and the people that we have here in Martinsburg."
In addition, all of the work is being documented and will be provided to the Air Mobility Command as well as the National Guard Bureau.
"They can see how this process is done," Teter said.
Tech Sgt. Ron Glazer Jr., an aerospace mechanic, is one of the wing's Airmen assigned to replace the two panels of crown skin.
"It's going well so far," Glazer said. "I love working these big jobs."
Asked what was the most difficult aspect of the project? The young airman noted that it is "very time consuming."
And when unexpected problems arise, Glazer said LaFaver is the go to guy.
"If we have a question we go to Chuck," he said.
In turn LaFaver is impressed with the caliber of Airmen tapped to work on the project.
"You ask them to do it and they lean forward and get it done," he said of the 167th Airmen tapped to work on the aircraft structural maintenance project.
Adding: "One way or another the aircraft will be back in the sky."