Unlike many of my courses in Naval Science, the classes on Naval Warfare were the most fascinating. With advancing science, the weapons of modern warfare were becoming technically interesting. The technology used in mines was also fascinating. Unlike older mines that detonated on contact, newer mines had sensors that could gauge the size or proximity of ships passing nearby, and detonate only when the proper signal configuration was achieved. Others mines might count the ships passing overhead, and detonate only after a predetermined number of passes had been recorded. These mines were all invisible from the surface without special detection devices.
In wartime, minefields could be laid out along coastal waters, harbors or rivers to discourage the passage of ships. Blockade of a harbor could be achieved with mines alone. As passive devices, mines remain submerged well after hostilities end, and pose serious threats to commerce until they are cleared from the waterways. Clearing mines was the task of the minesweepers, a small vessel tailored for the job.
The Hamilton County was a minesweeper tender designed to provide support for an assortment of minesweepers. By January 1956 when I reported aboard, the Navy had developed a minesweeper which had all the bells and whistles needed to sweep mines and avoid being blown up in the process. The following picture shows three sweepers, the Warbler (MSC-206), the Widgeon (MSC-208), and a third sweeper alongside the Hamilton County well prior to our deployment to the Western Pacific. The ships had only been in service for a few months, and had the latest in minesweeper warfare technology. Most of the sweepers and the Hamilton County were subsequently home-ported in Sasebo, where they served the Navy’s needs for the next 15 years. They were the cats whiskers in minesweepers at the time.
These sweepers originated the popular notion of wooden ships and iron men. The ships were designed to present a minimum magnetic signal, compared with metal hull ships. Their engines and associated equipment were built with nonmagnetic alloys wherever possible. Degaussing cable was used to neutralize the magnetic influence that could not be eliminated. For example, consumable goods in tin cans were stored in permanent places aboard ship. After they were used, the cans were washed, returned to the original boxes, and placed on the same storage shelves to avoid altering the ships magnetic characteristics. When the cooks failed to follow these rather explicit instructions, the result could blow the ship out of the water. This made the ships cooks extraordinarily attentive.
With their dangerous mission, it was essential that the ships, hulls, and all onboard equipment be tested for the ability to withstand water-born explosions, as may occur while actually sweeping for mines. As the flagship for minesweepers, the Hamilton County was to oversee the testing.
To prepare for testing, we loaded a dozen yellow mines on the main deck, ordered the helicopter to come aboard, and for the first and only time in a year and a half, the Admiral, Commander Mine Forces Pacific Fleet, came aboard with his staff to witness the testing. Once everything and everybody was aboard, we left for a remote island in the Catalina group off Southern California. As we were steaming into Catalina, the below picture shows the dozen yellow mines waiting to be used, the HUP-2 helicopter strapped to the deck, and Catalina Island dead ahead of the ships bow. We were about to find out exactly how sea worthy these little wooden ships and their iron men would be.
We anchored in a large protected cove to begin preparation for the testing. It was never quite clear exactly how the one minesweeper (MSC) designated for the testing was selected from among many. The admiral may well have asked for volunteers. Had they known that the crew would be aboard the ship as the mines were detonated, they might have had second thoughts about volunteering. As most MSC captains were Annapolis graduate JGs, they may have stood in line for the honor. In any event, one minesweeper and many of its crew were all aboard, at anchor a considerable distance from the admiral and the rest of us on the Hamilton County when the fireworks began.
The above is a schematic of the minesweeper (MSC) at anchor, while the yellow circles represent the mines placed at various distances and depths from the ship. Testing required the better part of a day, beginning early in the morning. Initially the most distant mine was detonated. Following each detonation, the crew on the minesweeper would check the ship for damage, making special note of anything that might be moved by the shock. The initial explosion may have been 150 yards from the ship and 30 feet below the surface.
After the ship was checked, the next nearer mine was detonated, and the routine was repeated. This went on throughout the day until all twelve mines had been detonated. The last few charges were designed to provide a lateral shock to the side (abeam) of the ship, and the final blast was almost below the ships hull, providing vertical thrust.
By and large, the remote explosions did little more than produce waves and a rocking motion commonly experienced by everything that floats. From about 50 yards and closer, items that were not securely fastened to the ship were moved by the jolt, but the little wooden ship was amazingly sturdy. The final few jolts were extraordinary in their impact on both the wooden ship and the iron men, with the men being the more resilient. On visual during the final explosion, the little ship appeared to be raised about four feet above its former waterline before settling back into the water.
There was no major damage to the wooden hull of the ship, although the main engines were reportedly knocked loose from their shipyard alignments. Virtually everything that could be moved, jostled, or knocked over, was moved, jostled, or knocked over. After a brief period of adjustment by the iron men, the little ship returned from the testing site on its own power. Their sea worthiness was beyond question following this brutal series of tests.
The test was not without its surprising outcome. The first detonations produced almost no visible consequences. The last few explosions produced hundreds of stunned fish in the cove. When the testing was over, the LCVP used to move men and equipment during the test was used to gather in the fish that had been stunned. For the better part of a half hour, the crew of the LCVP gathered fish until the bottom of the boat was covered with fish. Then it returned to the Hamilton County. The following picture shows the admiral on his only stay aboard the Hamilton County (left) and Captain Weatherby (right) struggling to hold two of the larger three fish which were captured in the exercise. The brightly colored black and orange fish, I was told, is a sheep’s head, while the larger gray-brown fish is a sea bass.
Because the cooks on the ship reported to me first, they asked if I would like some of the sea bass to take home. I said a small portion would be fine, enough for two meals. They filleted about two pounds and froze it for taking home. This was a fitting and delicious end of our testing. The fish was great and the wooden ships were amazing, but the iron men had earned their name and their reputation.