Subs Running ‘Blind’ Pose New Danger of the Deep

Carefully, deliberately and by the book, the crewmen maneuvered the U.S. Navy submarine up from the depths of the Mediterranean Sea.

They listened to the sonar for telltale noises. Nothing. All clear. The order was given to climb, but what happened next is the stuff of sweaty palms and sleepless nights.

As the periscope poked above the surface, the looming image of a 100,000-ton tanker came into focus, dead ahead.

“He was so big that even head-on, bow-on . . . we couldn’t hear his screws (propellers) through his hull, so we didn’t know he was there,” recalled retired Vice Adm. Patrick J. Hannifin. “We came up and went down in a hurry.”

Hannifin’s submarine got out of harm’s way. But last week off Los Angeles, the crew of the San Diego-based submarine Houston was not so fortunate. The crew of the tugboat Barcona was less fortunate still.

The nuclear-powered Houston, on standby for filming of the motion picture “The Hunt for Red October,” a fictional saga of a Soviet submarine skipper’s defection to the United States, snagged the Barcona’s steel tow cable and yanked the tugboat backwards and under in less than a minute. One crew member drowned and two others survived.

‘Mysterious’ Disappearances

A Navy spokeswoman in San Diego called the incident “freakish.” But only two days later, the Houston apparently sliced through a trawler’s fishing net outside the Port of Los Angeles. The Navy says it is investigating the incident.

And in recent years, the issue of submarine collisions has become a cause in the British Isles. Members of both the British and Irish parliaments are demanding to know what role submarines may have played in the “mysterious” disappearances,sinkings and close snaggings of several dozen fishing boats in the Irish Sea, resulting in the loss of more than 100 lives since 1980.

Officials with the U.S. and British navies have said that their submarines have not been involved in fatal incidents in the area. However, officials in both navies have confirmed details of several snaggings involving submarines and civilian vessels. In a Feb. 18, 1987, incident, a U.S. Navy submarine dragged

the Summer Morn, a British fishing boat, for three hours. The U.S. government settled a damage claim brought by the Summer Morn with a payment of 16,579 (roughly $25,000), a Navy spokesman said.

In 1982, the British Navy paid damages after the submarine H.M.S. Porpoise sank a fishing boat. All crew members were rescued.

“It’s quite extraordinary,” said Angus Peetz, a research aide to George Foulkes, a member of the British Parliament who has pressed for a full-scale investigation of the incidents. “They can hit targets 2,000 miles away, but they can’t spot a fishing boat above them.”

Preposterous as it may seem to the average civilian, Hannifin and other submarine experts say, highly sophisticated Navy submarines sometimes travel through the world’s oceans nearly blind to what is around them.

In fact, during some maneuvers, the submarine captain operates with a blind spot not unlike that of a driver changing lanes on a freeway.

Under Navy policy, submarines rarely use the sensitive “active” sonar systems on board because in order to do so they must emit signals that could reveal their location. Instead, they rely on “passive sonar,” which means carefully listening for engine noises, clanking chains or any other auditory clues.

But if a vessel is not making any noise, there is little chance that the submariners will detect it.

May Have Been in Blind Spot

Navy officials will not comment on the two recent accidents off the Southern California coast involving the Houston, a fast attack submarine, but evidence has emerged that at least one of the incidents occurred while the Houston was in a blind spot similar to the one described by Hannifin and other submarine experts interviewed last week.

The incident in the Mediterranean occurred more than a decade ago, but it illustrates a point that remains true today: surfacing from the deep is a maneuver that challenges even the most experienced skippers with the highest-tech gadgets on board.

“It’s that time when the submarine is most vulnerable,” Hannifin said. “He’s really blind.”

“The problem is that a submarine completely submerged can’t see anything,” said Hannifin, who was commander of all U.S. and NATO submarines in the Mediterranean from 1971 to 1973, then went on to become the director of the Office of the Joint Chiefs of Staff.

“It can hear, but it can’t see,” Hannifin said. “It can hear a fishing boat, for example, if the fishing boat is running its engines. What it can’t hear are fishing nets or barges being towed, because barges don’t make any noise.”

To minimize the chances of running into another vessel, submarines generally travel well below the surface. When it is time to ascend, they move swiftly to periscope depth.

“There is a period, truly, of uncertainty as you go through this transition from the deep submerged state to a shallow submerged state, and so you very carefully search around,” said Capt. Thomas C. Maloney, retired commanding officer of a nuclear-powered submarine of the same class as the Houston.

“You maneuver the ship to see if there’s some target behind you, and then you very quickly try to bring the ship up so you can look out through the periscope.”

Maloney described the transition period as a tension-filled time and compared it to an automobile on a freeway.

“Once in a while, you get ready to change lanes and all of a sudden you find there’s somebody in your blind spot,” Maloney said, “even though you thought you’ve done a pretty careful search.

“And once in a while when you come to periscope depth, you find there was somebody in your blind spot, for whatever reason.”

Such events occur rarely, Maloney said, and the explanations vary. Sometimes another loud ship in the distance masks the sound of the closer ship, he said. Or sometimes it’s simply a sailboat that was making no detectable noise.

“I would feel much more comfortable bringing my submarine to periscope depth off San Francisco or off Los Angeles than I am at night trying to make an entry into the Washington Beltway,” he added.

“We submariners recognize that the transition from being deep to coming to periscope depth is somewhat of a tense period and we give it special precaution.”

Still, active sonar, which is capable of detecting silent objects, is rarely used. Using passive sonar, a submarine crew member simply listens for noises, but with active sonar, the operator can send out sound waves that will bounce back to the submarine with a “ping” if it strikes an object.

‘Clutter’ Gets in Way

The active system works best in detecting totally submerged objects, Maloney said, but is less reliable when aimed at the surface. Depth, water conditions, surface waves and other variables all can generate sonar “clutter” that cuts down on reliability, he said.

But the overriding reason that active sonar is rarely used is security.

“When you use active sonar, you give your position away,” said James Bush, a retired Navy captain and former submarine commander who now works with the Washington-based Center for Defense Information.

“The way submarines live is by avoiding people knowing where they are,” Bush said. “That’s just the way of life, even though you’re operating in your own waters.”

Active sonar is generally reserved for “battle situations,” Bush said. “You’re going to shoot a torpedo at him anyway, so why not make sure you know exactly where he is.”

In any case, Bush and others said, it is highly unlikely that any sonar system would detect a fishing net.

Navy officials confirm that fishermen worldwide have been reimbursed for nets and catches lost when submarines accidentally sliced through them, but precise figures were not made available last week.

Bernard Moffat, General Secretary of the Celtic League, an organization that fosters cooperation among the Celtic areas of the British Isles, has been monitoring military activity in the narrow strip of sea between Ireland and mainland Britain known to submarine crew members as “Rat’s Run.” Since 1980, he said, there have been 21 disappearances of civilian vessels and more than 100 civilian deaths. The incidents have occurred in calm-to-moderate sea conditions, and Moffat claims that at least some of them probably are linked to submarines.

“We can’t say they’re definitely linked to submarines, but we can say most occurred in good weather to relatively modern vessels,” said Moffat, also an officer of the Transport and General Workers Union. “And in almost all cases, the incidents occurred in what are listed on admiralty charts as designated submarine exercise areas.”

In one case, a British trawler called the Laurel was snagged and pulled around for two hours before it cut its nets and freed itself, according to Moffat. The U.S. Navy is investigating the incident, and says in a report that it has found minor paint scrapes on the submarine “which were assumed to be the result of the snagging.”

Most of the submarines in the area are British or American, Moffat said, but Soviet, French, German and Dutch submarines also pass through.

Regardless of the nation, navies are extremely guarded about divulging details of submarine operations. Secrecy is paramount in the cat-and-mouse games that Soviet and NATO submarines play beneath the waves.

But Moffat sees in the secretiveness a kind of official arrogance. He suspects that Navy officials view the “disappearances” of fishing boats as a small price to pay to protect these weapons of nuclear war. To acknowledge the accidents, Moffat suggests, is viewed as both a compromise of security and bad public relations.

Based on his experiences, Moffat suggests the sinking of the Barcona might still be a mystery, but for the fact there were survivors to tell the tale.

“If there were no survivors, they would have never owned up. They would have just gone on their way.”

“That might explain why they owned up after a couple of hours because there were survivors. They would have to own up anyway,” he said.

In the case of the Laurel, the fishermen found part of the American submarine’s sonar equipment in its nets after the Laurel was freed. The U.S. Navy denied involvement, Moffat said, until the Laurel came into port and showed its unusual catch to the British media.

Peetz, the aide to British Parliament member Foulkes, said: “The more serious cases, where there are no survivors, then it’s more difficult to prove a submarine was involved. There’s no witnesses. There’s nothing.”