The 558th Aircraft Maintenance Support Squadron’s Corrosion Control Team, part of the Warner Robins Air Logistics Complex at Robins Air Force Base, Georgia (Houston County, Georgia, USA) recently completed a corrosion control mission with the goal of extending the service life of aircraft that could develop corrosion related issues.
Although extreme flight conditions are a pressing problem, Air Force personnel claim that corrosion has more costly effects, such as decreased service life of both the aircraft itself and their parts.
“The mission of corrosion control is to protect the aircraft,” says Todd Lavender, 558th AMXSS process engineer and squadron‘s corrosion control process manager. “It’s not for looks. It’s mainly for us to make sure there is not any corrosion associated with the aircraft so it can continue to fly longer.”
According to Lavender, the aircraft that arrive at Robins for scheduled programmed depot maintenance are processed and transferred to the corrosion control team for paint removal. “We masked the aircraft to begin the de-paint process,” he says. “Once that is completed, we apply a chemical mixture of benzyl-alcohol and peroxide onto the aircraft that takes the paint off of the aircraft.”
A key step in the product data management (PDM) process is removing the paint from the aircraft. “It is important to de-paint the aircraft so you can make sure you see all the areas that have potential to corrosion,” says Lavender. “There are specific areas on the aircraft that are more prone to corrosion than others. De-painting the aircraft uncovers and exposes the surface so they can make repairs as needed to the aircraft.”
Once the craft is de-painted, it undergoes PDM and, in the final stage of the process, is returned to corrosion control to be painted. “The paint gate is 7-12 days depending on the aircraft,” says Lavender. “It takes approximately four hours to add primer and topcoat. All the other days are surface preparation for masking and sealing the aircraft.”
As Lavender details, the first step is masking critical areas of the aircraft, followed by an application of non-chrome containing surface pretreatment over the surface that helps the primer adhere to the aircraft. About 189 gallons of primer, which contains hexavalent chromium that protects the aircraft from future corrosion, is applied, followed by approximately 200 gallons of topcoat.
Lavender estimates that about 3,000 man hours were required to coat each C-5 aircraft, along with approximately 35 people per craft. In addition, COVID-19 presented his team with a unique challenge.
“Throughout the pandemic, there were often times that manpower was reduced due to quarantine and isolation,” he says. “Many times, we had to combine painters from different areas within the support squadron. When you are accustomed to painting a specific airframe, it is sometimes difficult to quickly learn the techniques required to paint another airframe.”
Virtual reality (VR) technology was one solution employed by Lavender’s team and could be an option going forward by the Department of Defense in training its painting work force. Lavender says that the plan is to roll out VR aircraft paint training by mid-summer.
On the whole, Lavender is pleased with his team’s work. “It is a good feeling to know that we produced a quality product that is helping to get boots on the ground,” he says. “The corrosion control mission extends the lifecycle of our aged aircraft that fly missions worldwide in support of the Air Force and the warfighter.”
Source: Robins Air Force Base, www.robins.af.mi.