The shuttle: too many eggs in one basket

THERE is no room for complacency in the US space program. Despite the technological achievements of a quarter century of exploration, space remains a frontier. Operating there will continue to involve high risks and costs. A serious review of whether American interests are served by staking so much on the shuttle is long overdue. The disaster that befell the shuttle Challenger and its crew adds urgency to this issue. I don't intend to build analysis upon tragedy. But when America's most important space launch capability is cut by a quarter in a microsecond, we should ask whether we are relying too much on the shuttle.

The shuttle's $2.2 billion price tag makes it a very limited resource. What makes it worth the cost are the unique functions it can perform. But placing satellites in orbit is not one of them. No computer has been built that can compete with man in making observations and taking on-the-spot decisions. This human edge may be vital for conducting experiments and retrieving and repairing wayward satellites. But for launching payloads into orbit, man is a liability.

Manned systems are of necessity extremely complex. The human factor adds significantly to the cost of construction, operation, and maintenance. In the shuttle program, concern for crew safety has been a key factor in the frequent launch delays. In consequence, even before the Challenger disaster, the National Aeronautics and Space Administration could not keep up with the demands of its civilian and military customers.

The United States is the leader in space technology. As more nations and businesses learn that satellites can often do things better, cheaper, and faster than land-based systems, space commerce may provide a way to strengthen the US international trade position.

But as the opportunities for profit have grown, the competition in space services has intensified. Europe offers launch services with its Ariane rocket. And, the Soviets are in the business of launching commerical payloads into space.

While America's track record leads many customers to favor US launch services, the failure to fill orders in a timely fashion could erode this position.

But even if the shuttle could keep pace with customer demands, the economics of the manned orbiter means we lose by winning. Empty, the shuttle weighs 165,000 pounds. It can carry 65,000 pounds of cargo into orbit. When launch costs run at thousands of dollars per pound, where is the profit in lifting 3.5 pounds into space for each pound permanently placed in orbit?

For the time being, the advantage will lie with expendable space boosters. If the US is to retain its commercial position and make money at the same time, it should use its technological know-how to build a dependable unmanned system. The shuttle would have an important place in such a mix of capabilities. With satellites costing upward of $100 million a copy, the shuttle's ability to provide customers with on-orbit repairs and retrieval would give the US an edge over foreign competition.

The importance of military space operations has grown in recent years. Here, we do not need to look to futuristic ``star wars'' plans. Satellites that are vital to US security are in space today.

Satellites monitor arms control agreements and watch Soviet military activities that are free of controls. In event of nuclear attack, satellites would sound the alarm. Space systems have a dominant role in command and control of US forces overseas. Already, 70 percent of military communications pass through space. Military use of these systems is growing. Satellites will soon provide precise navigation and targeting information. Platforms in space may act as gunsights for weapons on the ground.

This dependence makes the military space network an increasingly attractive target for attack. The advent of antisatellite (ASAT) weapons is one result.

Proliferating satellites in peacetime and the ability to quickly deploy backups in war would cut vulnerability and reduce incentives for attack. It could also create conditions in which ASAT arms control is possible.

A robust space launch capability is key to this approach. But with the shuttle's capabilities already stretched, there is little chance that it can contribute to a proliferation strategy. And the shuttle's one-month recycle time would make it unsuitable for rapid replacement missions.

Nuclear deterrence is built on an insurance policy, known as the ``triad.'' In the event that one force element fails, there are others to take up the slack. Shouldn't the same logic apply to space launch?

The space shuttles are a national asset. Recognizing that their capabilities are special but not unlimited is the way to get the most out of them.

Alex Gliksman, director of strategic defense studies at the United Nations Association of the USA, formerly directed the US Senate Foreign Relations Arms Control Subcommittee staff.