NASA’s 2017 astronaut candidates (L to R) Raja Chari, Bob Hines, Joshua Kutryk, Jasmin Moghbeli, Jonny Kim, and Jessica Watkins toured aircraft hangar at Armstrong Flight Research Center, in Southern California. On the left, NASA’s, X-59 pilot, briefs them on use of F-15 for studying sonic booms during the development of the low-boom X-59 aircraft that is planned to fly supersonically over land. Low-level supersonic flight is not allowed at this time because of the loud noise levels generated when flying beyond the speed of sound.