Pictured is the crew of the "Question Mark," including, from left to right, Lieutenant Halvorsen, Capt. Ira Eaker, Staff Sgt. Roy Hooe, Maj. Carl Spaatz (mission commander), Lt. Elwood "Pete" Quesada, and an unidentified crewmember. During a 1929 operation dubbed "Question Mark," a 10,000-pound Fokker C-2A was refueled in flight by two modified Douglas C-1 transport aircraft.