Hellcats (6 page)

A branch of the equatorial current of the Pacific Ocean, the Kuroshio flows northeastward at a speed of approximately three knots along the coast of Formosa to Japan and thence into the Sea of Japan. The current continues northward until it reaches La Pérouse Strait, where it flows out into the Sea of Okhotsk. Voge pondered what hydrodynamic effect the inflowing or outflowing Kuroshio Current might have on a submerged submarine moving through the straits. Would it slow or speed up its passage?

The biggest drawback Voge saw to using the Tsushima Strait to enter the Sea of Japan was its minefields. Lockwood agreed. He believed that they posed a virtually impregnable barrier to penetration by submarines, surfaced or submerged, never mind the presence of antisubmarine air and surface patrols. Faced with having to penetrate an uncharted mine barrier, he and Voge focused instead on La Pérouse Strait. Intelligence reports indicated that it had a safe, unmined channel that the Japanese allowed neutral Soviet surface ships to use when sailing between the Sea of Okhotsk and the Russian naval base at Vladivostok on the Siberian coast. Intelligence indicated that the Japanese had sown mines in the La Pérouse channel at various depths between forty feet and seventy feet. This allowed Russian merchant ships—Japanese, too—to make safe passage, as very few ships in the world other than warships drew more than thirty-five feet of water. The mines, then, posed a danger only to submerged submarines, not surfaced ones.

Intelligence regarding the La Pérouse mine plants had been gleaned from various sources, including Japanese sailors picked up at sea from ships that had been sunk by subs operating close to Japan; from notices to mariners in the form of published bulletins distributed by the Japanese to local shippers, warning them of mined waters to be avoided; and from decrypted enemy radio broadcasts containing similar information transmitted to Japanese ships in the vicinity of the Sea of Japan. ICPOA had also picked up a few sketchy reports from spies who had made contact with Russian seamen familiar with La Pérouse Strait. Lockwood reasoned that if Russian ships could transit the strait via the safe channel, then so might surfaced American submarines. He also reasoned that even if a sub skipper didn't know exactly where the channel was he could always trail a Russian ship whose master knew what course to steer.

After sifting through these reports and weighing the pros and cons, Lockwood and Voge came to the same conclusion: It was high time that U.S. subs poked their bows into the Sea of Japan.

 

 

As Lockwood's plan to get
subs into the Sea of Japan began to jell, he took time out to undertake the West Coast inspection tour Admiral English's death had left unaccomplished. From Pearl Harbor Lockwood flew to Dutch Harbor, Alaska, then to San Francisco, ending his tour in San Diego. The submarine-repair facilities he toured were not as well equipped nor as efficient as Lockwood had hoped for. A lack of facilities and especially of trained civilian personnel hampered efforts to repair submarines and return them to the combat zone as fast as possible. Lockwood realized that it would take a special task force dedicated to the job of revamping the facilities and speeding up the workflow to accomplish what was needed.

While in San Diego Lockwood received an invitation from Dr. Gaylord P. Harnwell, director of the University of California Division of War Research (UCDWR), to visit the facilities Harnwell directed at the U.S. Navy Radio and Sound Laboratory (USNRSL) at Point Loma. UCDWR had been established in early 1941 to carry out research and development for the Navy under a contract let by the National Defense Research Committee (NDRC). Harnwell was a respected physicist and educator from Cambridge and Princeton universities. He had also taught physics at the California Institute of Technology and, before the war, had headed the physics department at the University of Pennsylvania. Steeped in advanced electronics and engineering concepts, he wanted to demonstrate for Lockwood some of the new prosubmarine gear, as it was called, undergoing development at UCDWR's labs. Because prosubmarine gear was high on Lockwood's list of priorities the sub force needed to counter Japanese antisubmarine measures, he eagerly accepted Harnwell's invitation to see what progress had been made in that area.

Earlier in the war Harnwell's efforts had been focused primarily on the problems associated with what was then called “subsurface warfare,” a discipline that encompassed not just antisubmarine weaponry but also mine detection. As the tempo of Pacific submarine operations increased, the need arose for devices to enhance the inherent stealth of U.S. submarines and to improve their survivability in combat. Harnwell and his staff of scientists had been working on such devices and were eager to demonstrate them for Lockwood's benefit. Not only did they have a rapt audience but also one who understood how difficult such specialized work was and how much time it had taken to develop the prototypes of the gear on display.

Harnwell demonstrated just about everything in UCDWR's inventory. It included a device that could detect an incoming torpedo's range and bearing; a sonar decoy similar to that of the German U-boat “pillenwerfer,” a cartridge filled with calcium hydride that when mixed with seawater produced huge quantities of hydrogen gas that bubbled like an out-of-control Alka-Seltzer tablet to confuse enemy sonar; ultrasensitive long-range passive—listening only—sonar for the detection of enemy ships; a bathythermograph, a device that recorded the varying temperature layers in seawater, which, because it had a masking effect on sonar, made submarine detection more difficult than it already was; depth-charge direction and range indicators; and, to help reduce a submarine's self-generated noise signature, a propeller cavitation warning device. Amazed at what he saw, Lockwood lamented that the sub force still lacked these “Alice in Wonderland” gadgets, which he believed would have vastly increased sinkings of Japanese ships and no doubt have saved hundreds of American lives. All he could do was put the devices on his wish list; he knew that despite the best efforts of Harnwell's scientists, it would take many more months of testing and refinement before the advanced prosubmarine gear reached the submarine fleet—if it ever did.

After conducting a tour of the lab, Harnwell sprang a surprise on Lockwood. Harnwell and his assistant, Dr. Malcolm Henderson, who, like Harnwell, was a brilliant, dedicated physicist, took their guest for a cruise off Point Loma in San Diego Harbor to demonstrate an experimental sonar device capable of detecting underwater mines and which was slated for installation in navy minesweepers. Henderson had led the group of scientists responsible for creating the device and was eager to demonstrate its abilities. Despite being a prototype with a spaghettilike breadboard electrical layout, the thing performed well enough to give Lockwood a peek into the future, even though, he admitted later, he failed to grasp its significance.

 

 

The device Harnwell had demonstrated
for Lockwood was called FAM-PAS, or Frequency and Mechanically Plotted Area Scan. Its name would soon be changed to Frequency Modulated Sonar and later shortened to FM sonar, then just FMS. The device used a then-new audio technique designed for commercial radio broadcasting called frequency modulation. Unlike AM, or amplitude modulation broadcasts, in which the audio carrier wave frequency is constant, the FM audio carrier wave varies in frequency. Conventional sonar units of the 1940s used a short pulse of sound transmitted on a constant frequency followed by a long silence as the return echo from a detected object was converted into an audible sound on the same frequency. By contrast, FM sonar emitted a steady, continuous signal modulated to avoid interference between the outgoing signal and the returning echo from a detected object, thus ending the requirement for a time lag. The experimental unit Harnwell demonstrated could locate submerged objects of every description, including shoals, sandbars, kelp, steel submarine nets, and even steel-hulled ships. In an earlier test it had even detected dummy mines. Realizing that such a device would interest Lockwood, Dr. Henderson explained that though FM sonar was originally developed for use by minesweepers, it could also be used by submerged submarines to plot a course into a defended enemy harbor.

Though Lockwood was impressed with Harnwell's and Henderson's Alice in Wonderland invention, he didn't see how the device could be used by a submarine. At that time submarine targets were concentrated in deep-ocean areas of the Pacific where an attacking sub had room to maneuver and to evade Japanese escort vessels. The harbors where Japanese ships sometimes took refuge from attack were in most cases too shallow for submarines to enter without being detected, even if they had a device that could plot a course into and out of a harbor, so it wouldn't make any difference. For Lockwood, FM sonar was an interesting gadget that not only proved the scientists at UCDWR were inventive, but also that the Navy's substantial financial investment in the lab was starting to pay off.

 

 

Lockwood returned to Pearl Harbor
buoyed by what he saw at UCDWR but disappointed by the long gestation period needed to develop the devices and to manufacture them in quantity for use by the sub force. Nevertheless, he reckoned that with his visit to UCDWR the force had established one of its most valuable contacts with the scientific world, and with Harnwell and Henderson, who would later play major roles in future submarine operations. After writing a report on his trip for distribution to Admiral King, Admiral Nimitz, and his own immediate staff, Lockwood put aside what he'd learned in San Diego for more pressing matters. At the top of his list was the get-acquainted look-see patrol of the Sea of Japan by a task force of submarines.

Lockwood wasn't sure what to expect from such a mission. He knew that Japanese ships were plying their routes in the Sea of Japan, carrying essential cargoes of food and raw materials back to mainland Japan. The big question was, How many ships were actively involved in this work, given that the bulk of the empire's merchant marine was busy elsewhere in the Pacific? How plentiful would targets be in the Sea of Japan? Would there be enough to justify the risks entailed in sending a couple of subs up there on a raid? He and Voge wouldn't know until they tried it. Furthermore, if submarines suddenly showed up in the emperor's sea, would the Japanese rush to block its exits, trapping the subs inside until they ran out of food and fuel, to be hunted down and sunk? Lockwood mulled these questions over for a time, then decided that the risk was worth taking, if for no other reason than it would provide the Navy's high command with vital information on the state of Japanese resupply operations at home. That information might influence future planning for an invasion of Japan, which would likely be necessary to end the war.

To avoid a prolonged operation in the Sea of Japan that would give the Japanese time to mount an aggressive defense, the plan Lockwood and Voge devised called for only a four-day hit-and-run raid that might just catch the Japanese napping and that would end before they could rouse their antisubmarine forces in strength. In May, Lockwood submitted his plan to Admiral King and Admiral Chester W. Nimitz, Commander in Chief, United States Pacific Fleet (CinCPac), for approval. A week later it came back with just one word over the admirals' signatures: “Approved.”

 

 

In early July 1943, three
submarines departed from Pearl Harbor bound for what some observers believed was a suicide mission into virtually unknown territory. Lockwood didn't agree, though the uncertainty of it all stoked his three-pack-a-day habit. Two of the three subs were the older prewar-built USS
Plunger
(SS-179), commanded by Lieutenant Commander Raymond H. Bass, and the USS
Permit
(SS-178), commanded by Commander Wreford G. “Moon” Chapple. The third sub was the new-construction USS
Lapon
(SS-260), making her first war patrol under Lieutenant Commander Oliver G. Kirk. Bass and Chapple were seasoned skippers with exemplary combat records; Kirk, also a veteran, had less combat experience than either Bass or Chapple. Another submarine, the big, old prewar USS
Narwhal
(SS-167), skippered by Commander Frank D. Latta, was dispatched to create a diversion by bombarding the island of Matsuwa To in the Kurile Islands northeast of La Pérouse Strait. Shells lobbed ashore from her twin six-inch guns would keep the Japanese busy and help the three subs make their getaway after completing their mission.

The Sea of Okhotsk, even in summer, is cold and fogbound. The subs groped their way west through the Kuriles for La Pérouse Strait, where they made their run-in on the surface at night at full speed, dodging fishing craft and navigating the safe channel by sheer guesswork. Most but not all of the Russian ships they saw had their running lights on to identify themselves as neutrals. Since none of the subs hit a mine, they and Lockwood had evidently guessed right about the location of the safe channel and the depth of sown mines. Bass, Chapple, and Kirk agreed that it was a hair-raising trip.

The submarines took up their assigned areas and at the appointed hour (Chapple in the
Permit
jumped the gun) began looking for ships to torpedo. As it turned out bad weather and intermittent problems with the raiders' vital SJ radar spoiled any chances they may have had to wreak havoc on the Japanese. Not only that, targets worthy of torpedoes proved scarce: Lockwood's suspicion that the bulk of the Japanese merchant marine was busy in the greater Pacific turned out to be correct. The
Permit
and the
Plunger
sank only three ships totaling roughly five thousand tons; the
Lapon
, already bedeviled by SJ radar problems, suffered from an inoperative Fathometer, which impeded skipper Kirk's determination to hunt for targets in foggy coastal waters off the coast of Korea. As it was, the
Lapon
encountered only sampans. Complicating matters, the
Permit
shot up a Russian trawler by mistake off Karafuto. Chapple, realizing his error, pulled thirteen survivors, including five women, from the frigid water. He considered landing them on Russian Kamchatka, but after a flurry of radio messages to Pearl Harbor, Chapple was ordered instead to off-load his passengers in Dutch Harbor, Alaska, to avoid a direct confrontation with angry Soviet authorities.