National Geographic : 1950 Sep
S; National UGoglraplic Society 302 Ektachroine from U.S.Air Force In the Rocket Ship Called the Bell X-l, Men Have Flown Hundreds ofMiles Faster than Sound First to penetrate the sonic wall-weird region of superspeed where air ceases to flow smoothly and piles up inbuffeting shock waves was Air ForceCapt. Charles E.Yeager (left), father ofthree. He named the bulletlike plane Glamorous Glennis after his wife. Since that historic date, October 14,1947, theAir Force's Glamorous Glennis and herNational Advisory Committee for Aeronautics twin, above, have punched repeated holes inthe barrier, with asuccession of pilots at thecontrols. Powered byfour liquid oxygen and alcohol rockets, theX-1 usually is launched bydropping from aB-29. and was designed tohit1,000 miles an hour initstwo and ahalf minutes offull-power flight. The Air Force hasannounced that "many times" theBell X-1 hasflown "hundreds of miles" anhour faster than thespeed ofsound, which varies with temperature from 760.5 miles anhour at59° Fahrenheit to 661.6 miles an hour inthe cold, thin airabove 35,000 feet. This is not a military airplane, but aflying laboratory for high-speed research. All supersonicflights of theX-1 and the Navy's Iouglas Skyrocket research plane have been made above Muroc Dry Lake, Edwards Air Force Base, California. There ahelmeted pilot squeezes into thetiny X-1 cockpit while his companion holds thedoor.