U.S. Air Force Capt. Joshua Fuller, 100th Operations Group instructor pilot, explains the headset to Spanish military firefighters prior to a flight, Oct. 23, 2015, at Son San Juan Air Base, Spain. The firefighters were given the opportunity to fly and watch air refueling conducted by the 100th Air Refueling Wing as part of Exercise Trident Juncture 2015. One of the primary objectives of the exercise is to demonstrate NATO’s visible assurance and NATO Force Response capabilities to tailor, plan, prepare, deploy and sustain forces. (U.S. Air Force photo by Senior Airman Christine Halan/Released)