(TINKER AIR FORCE BASE, Okla) No. 8 Squadron members from Royal Air Force Waddington, United Kingdom, Master Aircrew Tony Farmer, left, and Flight Lt. Dave Smathers, right, perform their preflight oxygen mask checks while Sergeant Phil Linning conducts preflight station checks before a mission. Members of the E-3D Sentry squadron conducted a liaison visit to the 552nd Air Control Wing to open the doors for future mission training and partnership. (Photo by Staff Sgt. Stacy Fowler)