Selfridge Airmen Train at Green Flag Published Sept. 8, 2011 NELLIS AIR FORCE BASE, Nev. -- Airmen and aircraft from Selfridge Air National Guard Base recently participated in the Green Flag-West exercise, which provides a realistic close air-support training environment for forces preparing to support worldwide combat operations. During the training air crews and support personnel from the 127th Air Refueling Group flew KC-135 Stratotankers, an air-to-air refueling platform with global reach. The exercise took place in August 2011 at Nellis Air Force Base, Nev.