Task: Explanation
Input (English): NASA's Astronaut Group 5 was selected by NASA in April 1966. Of the six Lunar Module Pilots that walked on the Moon, three came from Group 5. The group as a whole is roughly split between the half who flew to the Moon (nine in all) and the other half who flew Skylab and Shuttle, providing the core of Shuttle Commanders early in that program. This group is also distinctive in being the only time when NASA hired a person into the astronaut corps who had already earned astronaut wings, X-15 pilot Joe Engle. John Young labelled the group the "Original Nineteen" in parody of the original seven Mercury astronauts. Question: NASA Astronaut Group 5 includes the last living pilot of which North American test flight program? Answer: X-15
Output (English):  This group is also distinctive in being the only time when NASA hired a person into the astronaut corps who had already earned astronaut wings, X15 pilot Joe Engle.