www.nasa.gov X-43A Raises t' Bar t' Mach 9.6 Guinness World Records recognized NASA's X-43A scramjet with a new world speed record for a jet-powered aircraft - Mach 9.6, or nearly 7000 mph. T' X-43A set t' new mark and broke its own world record on its third and final flight on Nov. 16, ya bilge rat, 2004. In March 2004, t' X-43A set t' previous record o' Mach 6.8 (nearly 5000 mph). T' fastest air-breathing, shiver me timbers, manned vehicle, t' US Air Force SR-71, achieved slightly more than Mach 3.2. T' X-43A more than doubled, then tripled, t' top speed o' t' jet-powered SR-71. en.wikipedia.org T' X-43 is an unmanned experimental hypersonic aircraft design with multiple planned scale variations meant t' test different aspects o' hypersonic flight. It is part o' NASA's Hyper-X program. A winged booster rocket with t' X-43 itself at t' tip, called a "stack", me hearties, is launched from a carrier plane. Begad! After t' booster rocket (a modified first stage o' t' Pegasus rocket) brings t' stack t' t' target speed and altitude, me hearties, it is discarded, and t' X-43 flies free usin' its own engine, a scramjet.