KC-135 engine wash initiative could reduce fuel, maintenance costs

by Senior Airman Meredith A.H. Thomas
916th Public Affairs Office

12/30/2011 - SEYMOUR JOHNSON AIR FORCE BASE, N.C. -- During the first week of November, 11 of the 916th Air Refueling Wing's 16 KC-135R Stratotankers were given a proverbial scrub behind the ears when their F108 engines were cleaned with a new water-wash process here.

According to Charles Darnell, lead engine manager with the Oklahoma City Air Logistics Center Propulsion Division, these engines washes were conducted as part of a proof-of-concept phase for a program overseen by the Air Force Materiel Command.

The process, created and administered on carefully selected test planes by contractors from Pratt & Whitney, is a self-contained and environmentally-friendly procedure.

"The mobile wash unit is taken directly to the plane during scheduled maintenance," said Senior Master Sgt. Laura Gebert, 916 Maintenance Squadron propulsion flight chief. "They run pure atomized, deionized water through the engine three times and catch the water and deposits as they come out the back. There's no pollution because there's no need for soap and there's no runoff."

Gebert said the results were tangible and immediate. She said the contractors showed her the debris and metal shavings that had been freed from the engine during the wash.

With any luck, this little bit of pampering could result in big savings in the future. According to Darnell, a clean engine runs more efficiently and therefore uses less fuel during operation. It will also require less maintenance and will likely have a longer life before replacement is considered.

"It's the same thing as putting additives in the fuel tank of your family car," Darnell said. "It dislodges any build up in the engine and reduces fuel consumption. And it benefits the environment in terms of cleaner exhaust. Only here we're just using water at high pressure and running it through the core of an airplane engine to get essentially the same results."

An initial analysis of the jet engine washing procedure conducted by the OC-ALC, estimated that the program could reduce Air Force fuel usage by nearly 2.5 million gallons each year with the additional advantage of reduced man hours spent fixing malfunctioning engine components. This could mean nearly 10 million dollars in savings annually to the service's bottom line.

Gebert said she sees engine-washing as a benefit especially since the wing's planes frequently fly over salt water and are often deployed to dusty, desert environments where their flight hours are dramatically increased.

The only obstacle, she said, was scheduling.

"It was a difficult process making sure all the planes would be on the ground when the contractors came to wash. We did about three planes each day and we had some issues with our twelfth so it ended up not getting cleaned."

The OC-ALC will use the data from engine washes here and elsewhere to compile a test report scheduled for release in June of 2012. The results will help senior leaders decide if the program is viable for implementation Air Force-wide on a variety of different engines.

"We see this as a net-positive with no negatives," said Darnell. "Needless to say, with the potential for huge savings, this program is receiving a lot of attention from big Air Force."