Old Craft a New Idea in Air Defense : Blimps Could Still Have Role in Age of High Tech

It’s a throwback to the World War I generation of doughboys, Springfield rifles and Sopwith Camel aircraft.

As a flying machine, its reputation was permanently sullied by the spectacular 1937 explosion of the Hindenburg, and, in the new age of stealth bombers and space shuttles, it is as modern as the pterodactyl.

Be that as it may, the lighter-than-air ship, the old veteran of the world wars that never quite made it as a civilian, is making a comeback.

Old-time admirers of dirigibles (ships with a rigid inner structure) and blimps (bags with no internal framework) have long contended that they could be profitably used to transport huge cargoes or lift logs from remote timber-cutting operations.

But, until recently, modern blimps had only limited uses. The familiar Goodyear gas bags hover above championship sports events, carrying advertising and televising aerial views. In London, sightseers make reservations and patiently wait to plunk down 100 pounds for slow rides above the city.

Now, the federal government plans to test a blimp as a radar-interceptor of drug smugglers in the waters south of San Diego. Potential private customers are expressing new interest. One oil sheik, shopping for personal transportation, found the $5-million price tag on a comfortably appointed blimp reasonable. He decided not to buy only after learning that he would require a crew of 15 waiting to moor him wherever he wished to land.

The most significant new user, however, is the U.S. Navy. Spurred on by Secretary John F. Lehman Jr., it is about to award a contract for a new high-tech prototype blimp. It will be able to fly for a month at a time with a crew of nearly two-dozen, hovering low enough to refuel about once every three days.

This will be the first step toward a return to military service since the Navy phased out its blimps 25 years ago, and perhaps even be a renaissance for the majestic and maligned airship, which is still haunted by the newsreels of the hydrogen-filled dirigible Hindenburg’s burning like a blowtorch nearly 50 years ago.

At the end of World War II, the Navy had 168 blimps escorting convoys, hunting submarines and patrolling coasts. Some stayed in duty through the 1950s, and the Navy ordered a new model in 1960 to watch for enemy bombers approaching the northeastern United States.

But, once a string of radar stations was built across Alaska, Canada and Greenland to provide early warning, there was not much use for the blimp anymore. And, besides that, the Soviet threat to the United States had shifted from its lumbering bombers to intercontinental ballistic missiles capable of striking from the fringe of space.

Missiles Nearly Invisible

Now, the prospect of high-speed Soviet cruise missiles made of materials that make them nearly invisible to radar poses an unprecedented danger for the Navy and, ironically, may bring back the blimp.

Cost Put at $3.3 Billion

If the test blimp is effective, the Navy foresees spending as much as $3.3 billion for 50 ships and sending them to sea with naval convoys, carrying computers and giant radar transmitters to give early warning of enemy planes or cruise missiles. As they accompanied battle groups at an altitude of 5,000 to 10,000 feet, they would be able to see over the horizon, detecting sea-skimming missiles or planes at a distance of more than 150 miles.

“Our great concern is that they are going to get harder and harder to see,” Melvyn R. Paisley, assistant secretary of the Navy for research, engineering and systems, said of modern cruise missiles. “But the threat is not just the cruise missile. We also need to see fighters at higher altitudes. If we had this vehicle in the air today, it would be a definite improvement over what we have. It would surely increase our survivability right now.”

“In the 1990s,” another source said, “the Navy will face Soviet cruise missiles that can be launched from aircraft, submarines or surface ships and travel at two or three times the speed of sound just above the water. There isn’t any easy way to look over the horizon. Planes don’t carry big enough radar or enough data-processing equipment for this.”

If Congress can be persuaded that blimps would not be sitting ducks, the Navy would like to deploy them on both coasts, and perhaps even from NATO bases. Because there would be no crew changes at sea, the plan would be for a blimp to fly out of its base to join the fleet, relieving a previous ship after a 30-day tour.

According to Paisley, the first could be operational in six years.

Although the Navy is far from developing deployment plans, the first blimps would be likely to go to sea with battleship groups that would be operating without the radar aircraft that accompany carrier task forces.

But Navy officials see the further possibility that radar-equipped blimps may one day be deployed with carrier groups as well, to complement planes that establish radar pickets and provide battle management.

And Paisley further suggests a return to a former role in anti-submarine warfare. “Missions of all sorts could evolve,” he said.

The Air Force, for example, is considering the possibility of using new blimps to fly into radar sites in Alaska, Canada and Greenland, where weather conditions make helicopter and aircraft operations hazardous.

Role of Technology Cited

As much as the perception of new missions, the revived interest in the airship was brought about by vast, if inconspicuous, technological improvements--nearly indestructible fabrics, new composite materials as light as balsa and as strong as steel, compact engines that provide 100-m.p.h. dash speeds and controls providing maneuverability undreamed of when blimps last flew for the Navy.

The assignment to build the prototype will go either to Goodyear Aerospace Co. or to a partnership of Westinghouse Electric Corp. and Airship Industries Inc., a British firm with a fleet of five blimps operating in the United States, three of them scheduled to spend the winter in Southern California.

Goodyear has proposed a modern version of its venerable ZPG-3W, the last blimp it built for the Navy around 1960 and the largest non-rigid airship ever flown, containing 1.5 million cubic feet of helium.

Airship Industries and Westinghouse have proposed an even larger one--2.2 million cubic feet--a scaled-up version of the ships the British company has built for advertisers on four continents in the last few years.

“Although the emphasis right now is heavily on anti-air warfare,” said Westinghouse’s J. W. Phipps, “the potential for secondary missions such as coastal surveillance is immense. The applications have been around, waiting for the technology to catch up.”

Even after two years of testing, the Navy may decide that an operational airship must be bigger than either of the blimps it is now studying. To carry the necessary radar and equipment, Phipps predicted, an operational blimp will probably have a huge capacity of 3 million cubic feet of helium, making it twice the size of anything flown before.

Indeed, the Boeing Co. concluded that the Navy may need something that exceeds the prudent size of a blimp, even considering new super-strength fabrics available for the gas bags. It has proposed that the Navy consider a dirigible. Boeing engineers contend the time is at hand for the reincarnation of the rigid-frame ships with strong new composite materials for their shells.

Technological improvements have also stirred new interest in aerostats, or tethered balloons.

In the Bahamas, off Key West, Fla., and at Cape Canaveral, Fla., blimp-shaped aerostats with radar slung beneath them keep watch for drug smugglers, and six more are to be deployed along the border with Mexico.

Aerostat Use Weighed

Saudi Arabia is looking at the possibility of using the aerostat to keep an eye on the Persian Gulf.

After a bruising battle with Congress, the Reagan Administration sold the Saudi government sophisticated AWACS planes, including some of the country’s most sophisticated radar and data-processing equipment, for gulf surveillance and protection of its oil fields and ports.

But sources said the Saudis are now looking longingly at the possibility of aerostats along its gulf coast because it costs $1 million a week to keep AWACS planes airborne and the constant use rapidly ages the aircraft.