Last year's resumption of Soviet tests of a hunter-killer satellite in earth orbit has moved the United States to draw up its own plans to wage war in space.

With White House approval, the Pentagon has begun development of satellites that can sound an alarm if they're approached, a second alarm if they come under attack, and even fire a blast at an enemy satellite if it draws too close. Contracts to study all three methods of defense from enemy attack were given to six defense contractors last year.

"It's like 1914 or 1915 all over again," said a source close to the Pentagon, "when the pilots started carrying revolvers and shooting at each other out of the cockpits."

The Pentagon has also begun to study the need to give the spy, communications and navigation satellites more maneuverability so they can take evasive action in orbit if they are threatened. Also under the study is the need to have on standbt reconnaisaance satellites at Vandenberg Air Force Base in California that can be launched into orbit at a moment's notice.

At present the United States has only one Big Bird reconnaissance satellite at the same time in orbit, where it stays four or five months before being replaced. If the Big Bird in orbit were destroyed by surprise attack, it might be months before the Air Force could replace it.

"This is a very worrisome problem," a knowledgeable source said. "At the moment, we have no redundancy in our reconnaissance satellite system."

The Pentagon began to express concern last February when the Soviet Union resumed tests of its hunter-killer satellite, an unmanned spacecraft that blows itself up and destroys its opponent in the blast.

The Soviet had conducted 16 tests of the killer satellite from 1967 to 1971. Since resuming them in February, it has conducted at least six. The most recent test was done last month with a spacecraft called Cosmos 860 as the "target" vehicle and another called Cosmos 866 as the "killer" satellite. [TEXT OMITTED FROM SOURCE] exercises in which the killer [TEXT OMITTED FROM SOURCE]

Most of the tests have been ellite merely hunts its prey, drawing close enough to claim a kill. But at least one of the tests involved a real kill in which the interceptor drew alongside the target satellite and exploded both.

Concern over the threat of war in space has grown at the Pentagon as its reliance on satellites has grown. At least a dozen communications satellites in orbit link all U.S. military bases, ships and aircraft around the world. Another dozen navigation satellites guide the Navy's surface ships and submarines.

Particularly vulnerable to attack are the communications satellites, strung out like beads around the globe. These satellites are in what is known as synchronous orbit 22,400 miles high, where they match the rotation speed of the earth and stay in the same position above the earth at all times.

"They're up there like sitting ducks," is the way it was put by an intelligence source.

A killer satellite carrying a laser weapon could be flown into orbit 22,400 miles above the earth and move around the globe knocking out the Pentagon's communications satellites one by one. It could destroy the entire communications system of the Pentagon in about one week.

Because such satellites are so vulnerable, the Pentagon is thinking of positioning an entire array of communications satellites in orbit and then turning their radios off until needed.

"With their radios off," a source said, "the opposition couldn't track their radio beacons. And if they can't track them they can't find them."

Less vulnerable are the navigation and reconnaissance satellites, which fly in low orbit 100 to 200 miles above the earth and move around the globe at great speed. Their closeness to the earth makes them difficult to track from great distance in orbit because the curvature of the earth gets in the way of any killer satellite tracking its prey.

The Pentagon's precise plans to counter the threat of war in space are still secret, but sources said that among the first things to be done are to equip the next "generation" of military satellites with electronic alarm systems that warn of approaching satellites and more maneuverable rockets to evade the approaching satellites.

Some satellites will also be fitted with "impact warning" devices that radio they are attack even as they are being destroyed. The devices will enable the Pentagon to tell whether one of its satellites is missing because of a attack or whether it has suffered an accidental explosion or failure of its power supply.

No on thinks wars will be fought in space in the next 10 years, but the Pentagon plans to be prepared for it after that. When asked if the United States could fight a war on earth today if it lost its satellites in space, a highly placed source said succinctly: "Not successfully."