AFMC Command News

Tinker to refurbish F-22 air turbines

  • Published
  • By Howdy Stout
  • 72nd Air Base Wing Public Affairs
TINKER AIR FORCE BASE, Okla., --  Air turbines used in the F-22 Raptor are now being serviced by Tinker's 550th Commodities Maintenance Squadron as part of a new cooperative agreement that will see more than 30 components from the high-tech air superiority fighter undergo maintenance here.

In a joint agreement between private manufacturers Lockheed Martin, Honeywell and the Air Force, workers from the 550th CMMXS are refurbishing the air turbines that provide air from the aircraft's engines for the cooling of avionics and aircrews. An estimated 19 turbines will be repaired for the final quarter for 2009, with the number increasing as the aircraft reaches operational maturity. Work on the new turbines officially began June 30.

Under the agreement, Lockheed Martin is providing the parts and spares to refurbish the turbines while Honeywell provides the tools and training. The 550th provides the skilled labor.

"It's kind of a new way of doing business here at Tinker," said Mark Chenevey, turbine shop supervisor.

The turbines are relatively new technology, being developed in the late 1990s. They are used in the F-22 and several other aircraft in the Air Force inventory. Many older technology turbines are being replaced with the new turbines, meaning Tinker technicians will likely be seeing more of this type of work in the future.

Tinker was selected for this work because of its experience in turbine maintenance and testing. The unit repairs and tests turbines not only for the F-22, but for many legacy aircraft systems used by the U.S. and other air forces around the world.

"Most of the stuff we build in this building goes all over the world," says Tom Gallaway, a turbine tester for the 550th. The new air turbines are unique. The turbines take hot bleed air from an aircraft's engines and, through a combination of compression and expansion, cool the air for use in cooling avionics, aircrew and other equipment.

"It'll be 300 degrees when it comes in and 0 degrees when it comes out," explains turbine tester Rickey Nussbaum.

But, unlike traditional compressor turbines that use metal or ceramic bearings to reduce friction, the air turbines use nothing but air. With no touching metal parts, there is little heat generated and little wear among the moving parts.

"It's new technology," says Ken Kieltyka, program manager. "Where bearings produce friction, this one doesn't. There's no surface friction."

Like a hovercraft, the turbine rotates at up to 90,000 RPMs on a cushion of air.

Without surface friction, the new air turbines do away with lubricating oil. But gloves must be worn to keep skin oil from corroding the parts.

The 550th's testing facilities are relatively new, highly computerized and state-of-the-art. Turbine testers helped develop testing techniques for the new turbines in cooperation with Honeywell. Initial test results of turbines at Tinker mirrored those of newly-manufacturing turbines.