Firefighters extinguish an aircraft fire during training at the burn pit on Nellis Air Force Base, Nev., March 27, 2015. The firefighters are from the Merced County Fire Department’s Castle Fire Station 62, Atwater, Calif. The MCFD is responsible for responding to fires at Castle Airport, which was formerly Castle AFB, and trains at Nellis AFB every year to meet Federal Aviation Administration training requirements. (U.S. Air Force photo/Staff Sgt. Siuta B. Ika)