READY FOR PREFLIGHT Air Force Staff Sgt. Christopher Collins signals he is ready to perform preflight procedures during the Big Country Airfest on Dyess Air Force Base, Texas, May 2, 2015. Collins is a tactical aircraft maintenance technician assigned to the Thunderbirds, the Air Force Air Demonstration Squadron. SHARE: Download: Full Size (0.05 MB) Credit: VIRIN: 855550-M-KTI14-549.jpg Photo Gallery