Strategic Air Command


Atlas Missile Technical Information

     The original Atlas was 90 feet long and 12 feet in diameter.   It used liquid-propellant.  Its first design was called a "stage and a half" because it had a single main engine with side by side booster engines, all powered by liquid oxygen and kerosene. All three engines fired at launch, but the two boosters dropped away during the first stage burn.  This Atlas had a takeoff thrust of 350,000 pounds.  Course corrections were performed using small vernier rockets. 
      The Atlas was essential a thin shell.  There was no internal structural.  It was essential that pressure be maintained in the liquid oxygen and fuel tanks because the pressured shell gave the missile its structural integrity.  There were several versions of the Atlas.

Diameter: 10 ft. (not including strap-on boosters)
Length: 75 ft. 10 in. (85 ft. 6 in. in ICBM configuration)
Weight: 260,000 lbs. maximum at launch
Armament: Nuclear warhead on ICBM, none on scientific or Mercury flights
Engines (ICBM/Atlas D): Two Rocketdyne LR105-NA strap-on boosters & One Rocketdyne LR89-NA-3 plus two small vernier rockets for attitude correction (steering)
Engine Thrust at Launch: 360,000 lbs.
Crew: None (One on Atlas Mercury)
Maximum speed: Orbital velocity of about 17,500 mph. (approximately 16,000 mph as an ICBM)
Range: over 6,300 miles as an ICBM (the Atlas D could achieve orbit)
Maximum altitude: varied by orbital track (approximately 900 miles as an ICBM