By Peter Weiss
Proponents of exotic aircraft engines called scramjets say the technology might eventually make it possible to reach any spot on Earth in a 2-hour flight (SN: 9/19/98, p. 182: http://sciencenews.org/sn_arc98/9_19_98/fob5.htm ). Yet, in more than 40 years of development, no scramjet-driven craft has ever made even a short hop under its own power.
Now one has—but just barely.
On Aug. 27, the Defense Advanced Research Projects Agency (DARPA) in Arlington, Va., announced that DARPA-funded researchers at the company GASL, in Ronkonkoma, N.Y., had achieved the milestone. A small scramjet-equipped projectile, somewhat like an artillery shell and fired from a cannon, generated enough thrust to overcome air resistance, the agency reported. Instead of slowing down, measurements showed, it maintained a speed of more than Mach 7—seven times the speed of sound.