Assigned to the 86th Fighter Wing at Neubiberg Air Base, West Germany where he flew the F-84 Thunderjet and was among the first generation of Air Force pilots to successfully make the transition from propeller-driven craft to jets.
Served in the Korean War with the 69th Fighter Squadron and flew 20 combat missions in the Republic F-84.
Was a test pilot and instructor for the F-104 Starfighter at Lockheed Corporation.
Joined Lockheed’s Advanced Development Program in 1962, a top-secret program known as the “Skunk Works.” Gilliland became their Chief Test Pilot and was the first to fly the SR-71 Blackbird and test flew every Blackbird that came off the production line before it was turned over to the Air Force.
Logged over 6,500 flight hours and has more experimental supersonic flight test time above Mach 2 and Mach 3 than any other pilot.