SALT LAKE CITY – On June 2, Members from the Utah Air National Guard's 151st Maintenance Group and the Kansas Air National Guard's 190th Maintenance Group took on the monumental task of removing the tail from a KC-135R due to a hairline crack.
It started when pilots from the 151st Operations Group had to declare an in-flight emergency due to un-commanded flight control movement. They were able to land safely.
A team began troubleshooting the problem and zeroed in on a bad rudder power control unit. The installation of the PCU calls for a specific inspection of the attach point from the PCU to the rudder. During the inspection, Master Sgt. Amy Gauger, 151st MXG Non-Destructive inspector, found a 30-thousandths of an inch crack on the PCU mount by using an eddy current machine.
"It was in an awkward location. Seeing the piece is difficult because there isn't a lot of room," said Gauger. "The way that the eddy current machine works is it sends electrical currents through a solid piece of metal, and if there are any disruptions in the solidarity of the metal, it will give a readout to the machine."
After the crack was found, the aircraft was turned over to the 151st MXG Repair and Reclamation shop. This mount is not repairable in the field, so the entire rudder had to be removed and replaced.
"We took it off due to convenience and safety reasons, but it doesn't have to come off to work on it," said Chief Master Sgt. Kelly Cummings, 151st MXG superintendent. "For this issue, it is easier to work with the rudder while it's on the ground. If it's up in the air, it will be difficult for maintainers to maneuver between the horizontal and vertical stabilizer."
Cummings said tails have only been removed four times at Roland R. Wright Air National Guard Base and once at Hill Air Force Base to transport Utah's last KC-135E model aircraft to their museum for static display.
"It's pretty unusual to have a crack in the tail," said Cummings. "This particular aircraft was made in 1957, and the rudder has never been replaced, so it was likely caused from age and fatigue."
Several years ago, retired Master Sgt. Dustin Pippen, from the 190th MXG, came to Utah to help assist and train 151st MXG members on a tail removal. To return the favor, two members from the 190th MXG, who had not completed the task before, were invited out to Roland R. Wright Air National Guard Base to train on how to accomplish the job.
Master Sgt. Landen White, 151st MXG Repair and Reclamation senior noncommissioned officer in charge, planned the project to remove the tail.
"We needed to coordinate with multiple shops in maintenance to help get ready to remove the tail, such as the hydraulic shop, communication and navigation shop, and the electro environmental shop," said White.
They rented a crane that could pick up and move the 2,304-pound tail, which is 25 feet wide and 21 feet high.
With a special cable assembly attached to the tail, safety observers, a crane operator, and those working on unbolting the four pins and bolts from the tail removed it and placed it on the padded ground.
The 130th Engineering Installation Squadron brought their crane over to help detach the 875-pound rudder from the vertical stab.
"The 130th EIS has been helping us out a lot, and it saves us money by using their crane as opposed to having to rent another one from an outside agency," said White. "They helped us pick up the rudder after we removed all the hardware from the tail fin, and they put the damaged rudder into the cribbing to ship to Tinker Air Force Base for repair."
Lastly, the 151st Logistics Readiness Squadron assisted with the delivery of the new rudder. The refurbished rudder came out of Tinker AFB, Oklahoma, and costs approximately $85,000. After the refurbished rudder arrived, members from MXG quickly began preparations to reattach the tail to the KC-135R and get it back up in the air.
"I am impressed with the 151st Maintenance Group. They are extremely hard working and will stop at nothing to accomplish any job put in front of them," said Col. Kurt R. Davis, 151st ARW commander.