US Air Force band stages flash mob performance at Smithsonian museum Emerging from behind airplanes and space capsules, the United States Air Force Band surprised visitors at the Smithsonian National Air and Space Museum with a flash mob performance involving 120 musicians. The four-minute show was started Friday when Technical Sgt. Edward Prevost, a cellist, began playing after sitting down in a chair in the museum's "Milestones of Flight" gallery, according to the Colorado Springs Gazette. The full band soon joined in, playing an arrangement of Bach's "Jesu" and "Joy of Man's Desiring," as well as "Joy to the World," while vocalists emerged from the museum's second-floor balcony. The performance was led by conductor Col. Larry H. Lang.