In June 1958, Armstrong was selected for the U.S. Air Force's Man In Space Soonest program, but the Advanced Research Projects Agency (ARPA) canceled its funding on August 1, 1958, and on November 5, 1958, it was superseded by Project Mercury, a civilian project run by NASA. As a NASA civilian test pilot, Armstrong was ineligible to become one of its astronauts at this time, as selection was restricted to military test pilots. In November 1960, he was chosen as part of the pilot consultant group for the X-20 Dyna-Soar, a military space plane under development by Boeing for the U.S. Air Force, and on March 15, 1962, he was selected by the U.S. Air Force as one of seven pilot-engineers who would fly the X-20 when it got off the design board.