Three civilian NASA pilots who flew the X-15 rocket plane to the edge of space in the 1960s have received their astronaut wings, an honor originally given only to military pilots.
Bill Dana, John Jack McKay and Joe Walker were among eight pilots who took the research aircraft above the 50-mile altitude boundary that the military considers the edge of space.
While the other five were Air Force pilots and recognized as astronauts by their service, at the time NASA did not award wings of any kind to its own pilots. Today, the wings are given to space shuttle astronauts.
"Time and again, we asked them to risk their lives for our highest calling, the advancement of human knowledge, and they never let us down," said Kevin Petersen, director of NASA Dryden Flight Research Center at Edwards.
Dana was the only pilot to receive his wings in person Tuesday. Walker and McKay were awarded theirs posthumously.
The ceremony also reunited four of the five living X-15 pilots, with Dana joining Neil Armstrong, Joe Engle and Robert White.