National Geographic : 1960 Jul
HIGH SPEED EKTACHROME(OPPOSITE) AND KODACHROMES( NATIONALGEOGRAPHICSOCIETY Plastic Bullet Streaks From a Gun Like a Fiery Missile Falling to Earth In their study of ablation, Ames scientists fire tiny plastic nose cones from powerful gas guns into the rarefied air of an altitude chamber. Photographer Conger bolted a camera inside the dark chamber and left the shutter open, obtaining the view above. Hot gas surrounds the gun muzzle (upper left). The cone, speeding 12,000 miles an hour, draws a white-hot track before shattering at the end of the tunnel. Four six-inch naval guns are linked in tandem in a similar device at Ames. Compressed helium in the barrels propels the "bullet." Guns also simulate meteor hits on space ships. These metal tubes represent radiator pipes. One at right, filled with water, exploded when struck by a nylon pellet. The other, empty, sustained a neat hole.