Dave Darling, the “Cold Spray” site lead assigned to the 28th Maintenance Squadron, briefs Chief Master Sgt. Alan Boling, command chief for the 8th Air Force, on the “Cold Spray” technology initiative during a visit to Ellsworth Air Force Base, S.D., March 8, 2017. “Cold Spray” is the process in which small particles of the material are accelerated to achieve a mechanical bond upon impact, restoring the part back to the original specifications. (U.S. Air Force photo by Airman 1st Class Donald C. Knechtel)