Don”t get too excited that you might be able to reach Australia in just two hours. Reports over the weekend that NASA had broken to the world air speed record were a little premature. That the X-43A scramjet prototype had flown at seven times the speed of sound was true, but projectile was unpiloted. Dropped from a B52 (shown here taking off) it flew for 10 seconds on its own power over California, then glided for six minutes before falling into the ocean.