Cold spray could bring AF 10-1 investment return

  • Published
  • By Airman 1st Class Ashley J. Thum
  • 28th Bomb Wing Public Affairs
ELLSWORTH AIR FORCE BASE, S.D. --  Ellsworth's fleet of four-engine, swing-wing B-1 bombers continues to age, but a cutting-edge repair process may prove to be its fountain of youth.

Cold spray - a revolutionary technology used to fix surfaces such as worn fastener holes on aircraft skin panels - is expected to provide a 10-1 return on investment, and could save the Department of Defense approximately $100 million if implemented throughout the entire DOD.

Refined over the last 15 years, with successful applications by the Army and Navy, cold spray is now being looked at by Air Force maintainers as a method to make low-cost repairs on B-1 forward equipment bay panels - each costing between $150,000 and $225,000. Rob Hrabe, H.F. Webster Engineering Services chief executive officer, said the use of cold spray on B-1s will be a unique approach.

"Repairs are usually developed during a weapon systems' development," Hrabe explained. "In this case, we are applying a new technology to an older weapons system to keep it operationally viable longer, and to save precious maintenance and sustainment dollars."

Col. James Katrenak, 28th Maintenance Group commander, said the cold spray process will allow B-1 maintainers to save FEB panels that were previously not repairable.

"This is great technology to introduce to our B-1 fleet," Katrenak emphasized. "It could also be applied to other weapons systems."

Cold spray is the product of a partnership between base representatives, the Army Research Laboratory, the South Dakota School of Mines and Technology, H.F. Webster Engineering Services, MOOG Integrated Support Solutions, the Oklahoma City Air Logistics Complex, and other state and federal organizations. The prototype repair was developed at the SDSMT.

"The process involves spraying panels with powdered metal, using a carrier gas to accelerate the particles through a supersonic nozzle," said Dr. Christian Widener, SDSMT associate professor. "The metal particles impact the substrate at such a high velocity that they bond with the surface, allowing us to build up a worn surface without imparting the damaging heat of a normal welding process."

Victor Champagne, ARL Weapons and Material Research Directorate ARL Cold Spray Center director, has been instrumental in the development of this technology. He said cold spray could have a wide range of uses in the Department of Defense.

"This year, we are expecting the transition of cold spray into the first structural applications for rotorcraft," Champagne predicted. "We will be able to not only restore the dimensions of a part that has been taken out of service, but also the mechanical properties - such as hardness and strength - and bring it back to its original form. This will save the Department of Defense tens of millions of dollars per year."

F-16s and B-52s are also in line to benefit from cold spray, according to Brian James, Air Force Engineering and Technical Services representative.

Eventually, portable cold spray machines will be used at the base level to fix panels on-site. Katrenak stressed the importance of having cold spray as a repair option, adding it will greatly improve the base's ability to support contingency missions world-wide.

"One of the greatest challenges we face is aircraft availability," Katrenak said. "Having one B-1 out of the fight can impact our ability to do the mission."

Hrabe added that while the process is still a relatively new technology, it has unlimited potential.

"Cold spray is a way to tie Airmen on the flightline to research lab technology," Hrabe said. "I'm very hopeful that this will be a pathfinder event that will truly change the way we implement new technology on legacy weapons systems."

James noted it is often difficult to move forward with any new technology when a large number of people are involved and want to contribute their ideas, but in the case of cold spray, that system proved to be necessary.

"We couldn't have done it without everyone's help," James added. "Cold spray is going to take off."