Growing use of decoys   17-Feb-1989

Tricky Targets

'Smart' Arms Failure To Distinguish Decoys Has Pentagon Alarmed

It Is Developing New Systems That Sort Real From Fake In the Camp of the Enemy

Zeroing In on a Rubber Duck

By John J. Fialka

The pitched battle ended on a note of profound silence, to say nothing of embarrassment.

The U.S. Third Infantry Division had finally taken a hill after a day-long war game in the rolling farmland south of Nurnberg, West Germany.  The company of 11 enemy tanks just visible in the tree line had been strafed by aircraft, pounded by artillery and finally surrounded after four hours of simulated attack by an armored battalion five times its size.

Then the victors realized they had been had.  Only two of the tanks they had captured were real.  The rest were decoys, little more than plastic pictures tied to portable aluminum scaffolds.  Silence soon gave way to rage.  Soldiers began stomping on the decoys.

This mock battle, fought in the fall of 1984, was something of a watershed for the Pentagon.  Military planners began realizing that cheap, cleverly designed decoys can fool many of the armed forces' "smart weapons" arms that ferret out targets by using radar and other tracking mechanisms.

Arsenal at Risk?

The much-acclaimed smart weapons are grabbing a multibillion-dollar slice of the Pentagon's budget, and their share of the pie is growing.  Thus, the new concern about decoys.  The Pentagon is worried that the Soviet Union or other potential adversaries will use decoys to foil large parts of America's expensive, high-tech arsenal.  So the Pentagon has launched two campaigns: one to expand its own use of decoys to offset the proliferation of smart weapons abroad, the other to develop a family of "brilliant weapons."  Smarter than the mere smart weapons, these new arms will carry more sensors and possibly even a computer to distinguish enemy decoys from real targets.

The vulnerability of some current smart weapons will give the Bush Administration something to consider as it reviews the nation's defense, and looks for places to cut costs.  Much of the Army and Air Force's future battle planning is tied to a so-called Follow-On Forces Attack strategy that uses far-seeing sensors and smart weapons to destroy mere indications of enemy targets a blip on a radar screen or a blotch of heat many miles behind enemy lines.

On paper or at least in a recent computerized Pentagon war game the strategy works.  But one thing the simulation didn't take into account was the possibility of an enemy's abundant use of decoys.

'Seeing' With Sensors

"People will have to think all this through," given the growing use of deception, says Gen. Glenn K. Otis, recently retired commander of the U.S. Army in Europe.  Decoys "are important now, but they'll become even more important as we go to sensors rather than eyeballs."

Compared with the high-tech architecture of smart weapons, the anatomy of many decoys is startlingly simple.  Take, for example, the decoy tanks that duped the army in Bavaria.  The attacking tank commanders activated their new M-1 tanks' infrared sights, which measure heat, and saw familiar patterns of thermal blotches across the front of the "tanks" holding the hill.

But they saw the pattern only because TVI Corp., the Beltsville, Md., company that makes the decoys, laminated electrical heating devices into its life-size plastic pictures of tanks.  The devices were powered by small, portable generators humming away behind each scaffold.

Stephen P. Rosa, a TVI vice president, says he got the idea after watching Army tank gunners focus on the blotches during exercises on target ranges and in tank simulators.  "All we do is feed them back what they're trained to see."

Foiled by a Fowl

Some military minds have begun to warm to this simple idea:

The Navy is putting to sea a British device called the "Rubber Duck" to fool anti-ship missiles.  When a captain is threatened by a missile, he drops the bundle overboard and it rapidly inflates into two eight-sided, life-raft-sized objects tied together by a short rope.  The Duck is designed to mimic a ship's radar image, which consists of many corners and shifting patterns of reflection.  In theory, the decoy will cut in half the chances of a smart missile hitting the ship.

The Air Force and the Navy have commissioned a number of companies to develop an anti-missile decoy that is reeled out from the rear of a plane like a fishing lure.  Towed at some distance, it transmits a radar signal that mimics the image of a real plane, and thereby draws an incoming missile away from its actual target.

The Army Materiel Command is developing a small, field-portable radar with a computer memory and the capability to send out a variety of decoy signals on order.  The unit first identifies the incoming enemy radar signal for example, that of an attack helicopter scouting for tank convoys.  It then searches its memory and retrieves and sends out the radar reflection of a tank convoy.

The payoff from decoys is huge.  The TVI decoy "tank," for example, costs a little more than $3,000; yet, in addition to saving lives, it could attract enemy missiles and artillery shells worth hundreds of times that.  The tank decoy weighs 40 pounds and can be carried by one man in a dufflebag.  During his campaign to sell it to the military, Mr. Rosa set one up in the foyer outside a Pentagon official's office in 10 minutes.

So far, the Army has bought 1,400 of the tank decoys.  Martin E. Falk, the Army's project officer in charge of battlefield deception, would like to buy more of them, but he says many Army commanders are still dubious.  They would rather spend their money on real weapons.  "Heck," argues Mr. Falk, "if you save one M-1 tank [at 3 million apiece], you've just about paid for the cost of my entire program."

The U.S., of course, has used deception and decoys in the past.  Before invading Normandy during World War II, the U.S. fooled the Germans into thinking the real landing would be at Calais.  The deception involved faking whole bases, and making it seem that Allied forces were massing in a certain part of England.  The trick ultimately kept 10 German divisions diverted for a week.

After that, however, the Pentagon's interest in decoys waned.  Eugene G. Fubini, a member of the Pentagon's board of science advisors, recalls that when he was an assistant secretary of defense in the 1960s, he tried to earmark several million dollars for the study of deceptive tactics.  He later discovered the money had been re-budgeted to buy weapons.

Drumming Up Interest

He says, "So I put the money in again and the money disappeared again.  I concluded that the feeling around the building was that deception was un-American."  Mr. Fubini, a physicist who is familiar with many high technology weapons systems, continues to worry that the U.S. doesn't have any coherent strategies to use deception or defend against it.

"If you say that very many of our weapons can be [deceived], you are right," he says.  "The money being spent on decoys is a ridiculously small amount."

The money at risk, on the other hand, is significant.  Consider the consequences of launching the Army's new, $1 million Tactical Missile System at a relatively cheap black box generating a spurious radar reflection of a Soviet tank column.  Consider also as Tom Clancy did in his book, "Red Storm Rising" Navy fighters firing off radar-guided, $875,000 Phoenix missiles at obsolete Soviet missiles used by the Russians to mimic bombers.

Daniel Goure, an analyst of Soviet military systems for SRS Technologies, a Newport-Beach, Calif., research firm, says the Russians are well along in their consideration of decoys.  He says there is a large amount of new Soviet military literature devoted to the subject of deceiving smart weapons through "Maskirovka," or deceptive tactics that are a tradition in the Soviet military.  A Navy official adds that recent Soviet articles discuss how to "seduce" incoming missiles with false virtual and radar targets.

Enter "brilliant weapons."  Dr. Thomas P. Rona, who was President Reagan's deputy science adviser, endorsed the need for these weapons in recent article he wrote entitled "Will Smart Weapons Become Decisive in Military Engagements?"

Finding the Target

In the article, Mr. Rona calls for the development of a "brilliant precursor missile" that flies into enemy territory, distinguishes between real and decoy targets, and then drops signal beacons in the vicinity of the real targets.  Smart missiles then home in on the beacons.  Mr. Rona couldn't be reached for comment.  An aide noted that many of the details concerning the subject were secret.

Cost will be one of the biggest hurdles in developing these systems.  Cramming sensors, a memory and computing capability onto a rocket to make it a brilliant missile raises problems with miniaturization that are very expensive to solve, according to Tom Baranauskas, an electronics analyst for Forecast Associates, a Newton, Conn., market research firm.  Moreover, future smart missiles will be supersonic (current ones are nearly all subsonic), so they will have less time to distinguish the real target from the fake ones, he notes.

For now, though, military contractors are busy improving the intelligence of what were once simple decoy systems.  Since pilots have little time to evaluate and react to incoming missiles, Tracor Inc., an Austin, Texas, company, is developing a smart decoy dispenser that decides what type of decoy to use.  If the system determines a heat-seeking missile is chasing the plane, it may drop flares to confuse it.  If it senses a radar-guided missile closing in, it may throw out cartridges of tinsel-like aluminum chaff to fool the radar.

Pilots used to use onboard instruments to jam radar-guided missiles.  The newest smart missiles overcome this defense by simply homing in on the jamming device.  So Tracor and other decoy companies are developing jammers that reel out from the back of the plane, so they are several hundred feet behind the aircraft.

The result: the aircraft escapes, and a new problem is created for a brilliant missile to solve.