Science: Missile Plane

After months of hesitation, the U.S. Air Force last week signed the orders for development and production of System 464-L, a manned, maneuverable space vehicle called Dyna-Soar. Reason for hesitation: the program will cost an estimated $700 million over the next ten years.

Dyna-Soar is the U.S.'s closest approach to a true spaceship. The X-15 rocket plane will only cruise along the shoreline of space (80 to 90 miles up) at about 4,000 m.p.h. The astronaut in the Project Mercury capsule will have virtually no control over his vehicle, will be able to...