Sherry Sontag;Christopher Drew (21 page)

Trieste made nine dives that year. Watching the first from monitors aboard the floating dry dock were Craven and Captain Harry Jackson, the engineer who had helped test Thresher and never stopped being haunted by his near-miss on that sub. They could see that there was no evidence of attack, and no evidence of an external torpedo hit. But there was also no conclusive evidence to show just what had sent Scorpion to the ocean bottom.

Craven would always struggle with the last piece of the puzzle. He was nearly certain a torpedo blew up inside Scorpion. But how)

It all seemed to end there, with the question left unanswered, with the families of the Scorpion men left to wander in nightmares of explosions and phantom battles and disbelief.

"All we ever wanted was an explanation," said Barbara Baar Gillum, who lost her twenty-one-year-old brother, Joseph Anthony Baar Jr. "After the disaster everything was covered up."

The Scorpion disaster quickly faded from the greater public conscience, which was already being battered by nightly images of bullets flying, soldiers bleeding, and a seemingly endless line of body bags in Vietnam. The Scorpion families might have been left alone to forever struggle with their own investigations had the Navy not decided to mark the grisly quarter-century anniversary of Scorpion's loss by releasing the court of inquiry's conclusions and videotapes of her sunken shell.

By then, Craven was sixty-nine years old and long gone from the Navy. He was, instead, intensely involved in developing a new form of agriculture in Hawaii. The Chicago Tribune printed a story about the documents and his role in using his torpedo theory to find Scorpion. It was only when that story ran that Craven was handed what he is convinced is the last piece of the puzzle.

It all played out in a scene reminiscent of the final chapter of a detective novel. The Tribune article reached the desk of Charles M. Thorne, who had been technical director of the Weapons Quality Engineering Center at the Naval Torpedo Station in Keyport, Washington. Seeing Craven's name in print, Thorne picked up the telephone and dialed.

The two men had never met. Neither had known anything about the other during the long Scorpion search and all the years after. Still, they had much in common. Thorne, too, had long had reason to fear that a torpedo had been the cause of Scorpion's death. Back in the summer of 1968, he had been a top engineer in the Keyport lab responsible for testing torpedoes and their components. He worked there for twenty-five years, and by the time he called Craven, lie had been retired for twelve years. All that time he had held information about Scorpion that he felt barred by classification rules from telling anyone. Now the engineer reached out to the scientist.

Thorne asked Craven whether he had seen a classified alert that had been mailed in mid-May 1968 to the department that had been renamed the Naval Ordnance Command. The letter described a test failure of an MK-46 battery that was designed to power the Mark 37 torpedo, a fastmoving warshot that had been deemed the primary weapon for use against Soviet subs. He was referring to an alert that the testing lab had sent to Rear Admiral Arthur Gralla who headed that command. Then Thorne went on to describe its contents. He knew them well since he had written the alert himself, although it had been reviewed and signed by Captain James L. Hunnicutt, the CO of the station and a decorated World War II submarine skipper, who has since died.

In the alert, the lab reported that a torpedo battery had exploded in flames during a vibration test because a tiny foil diaphragm, a part worth pennies, had failed. As Thorne related this to Craven, the news seemed to parallel the discovery that the failure of inexpensive rubber 0-rings had caused the space shuttle Challenger to explode. About a yard long and 17 inches wide, the batteries on Mark 37s were bolted within about an inch of the torpedo warheads. And each warhead carried 330 pounds of HBX explosive.

The lab's alert had recommended that all batteries from that production lot "be withdrawn from service at the earliest opportunity," and it said that sufficient heat was generated in the test sample "to risk warhead cook-off and loss of a submarine."

This alert was the strongest of any ever issued by the testing lab. It was the only time in the lab's twelve years of operation that it had ever warned of the possibility of a failure that could have life-threatening consequences. It was because the engineers were so deeply concerned, that they had their commanding officer sign the alert. They wanted the added emphasis.

Scorpion was carrying fourteen Mark 37 torpedoes, and she was lost days after the letter was sent. Horrified at the possible connection, lab engineers specifically asked the Naval Ordnance Command about the torpedoes Scorpion was carrying. The Navy keeps records and serial numbers of all torpedo components and where they are issued. One of the lab's engineers remembers being told verbally that one of the batteries powering a torpedo on Scorpion did indeed come from the same production lot as the torpedo battery that had exploded at Keyport. (Other former engineers there said they did not remember hearing this.)

Over the past several years, one of the engineers made requests for the battery records under the Freedom of Information Act, hoping they might answer that question once and for all. But the answer came back twice that no such records could be found.

Still, Thorne believes that a warhead cook-off initiated by a battery fire was the likely cause of Scorpion's loss, and he became all the more convinced of that when he read that Craven had concluded that Scorpion had suffered an internal torpedo explosion. He was stunned that Craven had never seen the lab's alert. Thorne had always assumed that the secret missive had been shown to the people involved in trying to make sense of the Scorpion disaster. Now it seemed that vital information had been withheld from Craven and the court of inquiry.

Thorne asked Craven for a copy of the videocassette of Scorpion's wreckage and the court of inquiry report. After viewing those, he wrote to Craven with his analysis.

"I have agonized for years over what more we might have done to have averted that tragedy," Thorne said in the letter. "The people that did the testing, the workman and other engineers, we all wondered. We asked questions."

Thorne then went on to tell Craven that his worst fears were borne out by Scorpion's wreckage. The videotape clearly shows that the upper hatch covers of the torpedo-loading hatch and the escape trunk hatch are gone. Both hatches lead into the torpedo room. Both, Thorne wrote, could have been blown away as a result of a violent explosion inside the torpedo room, and that could have resulted in massive and uncontrollable flooding of the submarine.

The battery failure that prompted Thorne to pen the alert was easily the most severe the lab had ever experienced. The test failure happened on a Saturday afternoon as three engineers-John Holman, John Grobler, and Robert Trieschel-subjected one of the 250-pound batteries to strong vibration. They had just walked out of the room where the tests were conducted when there was a tremendous explosion, strong enough to rattle the 2-inch solid wooden door. Holman threw the door open and ran in. The mechanism meant to shake and vibrate the battery was all but obscured by blue-green flames shooting 10 feet to the ceiling.

"Fire!" he yelled as he grabbed an extinguisher. The room began to fill with black smoke and flames. Two technicians were missing. Holman got on his hands and knees and began looking for them as fire trucks screamed up to the laboratory.

Chemical extinguishers failed to put the fire out. The men slipped rags over their faces and began unbolting the still-burning battery from the shaker. The battery exploded a second time, drenching them in the potassium hydroxide solution that served as the batteries' electrolyte. Shrapnel was embedded in the ceiling and walls.

The engineers took the burning battery out of the building. Its 16gauge steel case was peeled open like foil and the silver plating on the battery was partially melted. As soon as they could they raced back inside to drench themselves in the laboratory's emergency showers. Then the three lab employees and three firemen were rushed to the hospital to be treated for smoke inhalation and chemical burns. The lab called for the recall within two or three days of the incident.

A similar battery failure on Scorpion could have been enough to cause a warhead to explode, but the alert was sent too late to save the sub and crew. The phrase "withdrawn from service at the earliest opportunity" was usually construed to mean that a recall should be conducted as each boat reached port. When the recommendation reached the ordnance command, Scorpion was either already lost or still en route to Norfolk, where the recall would have been implemented.

Had the alert been made available to Craven right after the accident, months might have been shaved off the search for Scorpion. But instead of sharing the information, the ordnance command continued to insist that such an explosion was impossible. Had the court of inquiry been given the information, it might have done much more to solve the mystery. But the court in its report clearly relied heavily on Naval Ordnance's statements about the impossibility of an onboard detonation.

That the lab's alert made it to the ordnance command seems certain. It was specially coded to be routed from the mail room straight to the commander's desk. In addition, some weeks after Scorpion's wreckage was found, a representative of the ordnance command showed up at the Keyport lab, called Thorne into a private office in another building, and castigated him for including warnings of warhead cook-off and loss of a submarine in the alert.

The command had good reason to he deeply concerned by what Thorne wrote-Naval Ordnance had created the potential for catastrophe by bypassing its own safety procedures. In its effort to keep up with the sub fleet's demands for the torpedoes, it had rushed the weapons into production. The fleet desperately needed torpedoes that could go fast enough to catch the new classes of Soviet nuclear subs, but manufacturers were having a terrible time building components that could pass safety tests. There was such a backlog caused by repeated battery failures that the Keyport lab was at least two months behind in its quality assurance tests. Rather than slow down production, the ordnance command had been issuing torpedoes with components from lots that had never been safety tested at all. That was a clear violation of regulations that required that three samples from every lot of one hundred batteries be tested before any battery from the lot was issued to the fleet. The samples were supposed to be subjected to two or three weeks of tests measuring their resilience to shock, heat, vibration, and any other condition that could be expected to occur on a submarine. Only after the samples passed muster was the ordnance command supposed to allow any of the components on hoard any submarine.

Two companies had originally contracted to manufacture the batteries and suffered so many failures that the Navy brought in a third company to try to make up for the production problems. That company never managed to produce any batteries that passed quality assurance tests, but because of the shortages, the contractor was allowed to ship as many as 250 of its batteries to the fleets. It was one of the third company's batteries that exploded in the lab.

All three companies were having problems because the basic design of the batteries was dangerously flawed. Engineers had warned of this from the first failures back in 1966, well over a year before the catastrophic explosion that resulted in that last and strongest alert. Throughout that time, they had said the batteries had no margin of safety and recommended a redesign. The ordnance command was unwilling to do that.

The problem existed in how the batteries were activated. A sliver of foil that governed the flow of electrolyte into the power cells was etched to be only one seven-thousandth of an inch thick. That was because it was supposed to break with pressure, allowing the battery to power the torpedo's propulsion motor when the weapon was activated.

In a typical hot run, the kind Craven imagined had occurred, a torpedo receives an inadvertent start-up charge, fully activating the battery and also turning on the motor. That condition is easily detected as a spinning propeller on the torpedo alerts crews to the need for an immediate 180-degree turn.

The kind of failure experienced in the lab was far more insidious because there never would have been enough power in the battery to turn on a motor, or cause the torpedo propeller to spin. Instead, what happened to the batteries in the testing lab, and what caused the explosion of the test sample, was more difficult to detect. The lab discovered that when the batteries were subjected to vibrations, the electrolyte was pushed against that thin diaphragm with enough force to only partially rupture the foil. This allowed just enough electrolyte to slowly leak into the batteries' power cells to cause them to begin to spark and overheat. It was precisely because the diaphragms broke so easily, and the overheating condition could remain hidden until a fire or explosion that the lab determined that the design had almost no margin of safety.

During the vibration test that Thorne described in his letter, there was no hint of a problem until the battery exploded into flames. If the same thing had happened on a submarine, it was entirely possible that no one would have noticed anything was wrong unless they smelled insulation burning or touched the torpedo and felt heat. By then, the battery could have been only minutes away from exploding.