Science: MISSILE FAMILIES

Each of the armed services has a big family of missiles in operation or development. Outstanding items:

AIR FORCE

Falcon. Probably the most sophisticated missile now in large production is the small, graceful, air-to-air Falcon (Hughes Aircraft Co.). It is 6½ ft. long, 6 in. in diameter, weighs 120 Ibs. Its guidance system contains as many electronic elements as four television sets, all crammed into the space of a 2-lb. coffee can. The Falcon is a good example of the complication of missiles. The fighter plane that carries them is guided by ground radar until it is 20 miles from an invading bomber. Then the fighter's own radar picks up the target, locks onto it, and analyzes its relative motion. During this phase, the slim Falcons under the fighter plane's wing are quiet and lifeless. When the target approaches the Falcons' range, the pilot throws a switch, and the Falcons wake up. Their little gyros spin; the antennae in their noses search for the enemy. What the Falcons' delicate senses are looking for is a stream of radar pulses reflected from the target. When they "see" it, their radars lock into place.

At the proper moment, a Falcon takes off with a great stab of flame. In seconds it reaches high supersonic speed. The nose strikes through the target's wing or body, and a charge of explosive detonates inside. When tested against a drone F-80 jet fighter, one of them flew up its tailpipe.

Bomarc (Boeing) is a supersonic, long-range antiaircraft missile launched from the ground. Boosted into the air by an Aerojet rocket motor, it flies during most of its course on two ram-jets (Marquardt Aircraft Co.). It carries a warhead whose fireball is capable of knocking out more than one bomber of an invading fleet. When in operation, the Bomarc will be stationed in sheds on likely tracks of enemy bombers. Designed to be fired at a moment's notice, it can cover several hundred miles while a manned interceptor is getting clear of the ground.

Navako (North American) still has high priority. A long-range missile, it has wings, flies in the atmosphere much more slowly than a ballistic missile in dragless space, is therefore more vulnerable to enemy attack. But it has advantages. Carrying a thermonuclear warhead, it steers by the stars. An amazing little instrument picks out a succession of stars, even in daytime, and navigates by them like a ship at sea. Unlike the ICBM, the Navaho can be instructed to zigzag and feint. When the Navaho nears its target, it can feel for the warmth of a darkened city.

ARMY

The Army's territory is ground-based antiaircraft weapons and surface-to-surface missiles of anything except extreme range. Army doctrine is that missiles are fine things, but they must be rugged, transportable, and easily concealed. Most important of all, they must be "G.I.-proof"; they will be under the care of plain soldiers, who will drop them, kick them, neglect them, spill ketchup on them. If made like laboratory instruments, they will not perform on the battlefield worth a G.I. damn.