An Air Force combat controller hammers a distance marker into place before the start of an austere landing exercise in Plovdiv, Bulgaria, Feb. 9, 2016. The airman is assigned to the 321st Special Tactics Squadron. Combat controllers participated in the training for multiple aircraft deployed to Bulgaria as part of Operation Atlantic Resolve, which demonstrates the commitment of the U.S. to the security and stability of Europe. Air Force photo by Airman 1st Class Luke Kitterman