In lieu of an abstract, here is a brief excerpt of the content:

7 The Sorry Sasori 1-203, a Sen-Taka or high-speed submarine, was similar to the German Type XXI, both designed as ultramodern attack submarines capable of very high bursts of speed to break contact with the enemy. Completed in May 1945, 1-203 was 259 feet long and displaced thirteen hundred tons. The designed underwater speed was about twentyfive knots-almost three times that of the American fleet boat. She was about 50 feet shorter than a U.S. fleet submarine, and her draft three feet deeper. A very high length-to-beam ratio contributed to her high speed. After sea trials, bow planes, and huge stabilizer fins amidships were added to improve stability, and hydraulically operated valves for free-flooding the deck areas were eliminated. These changes reduced the top submerged speed to nineteen knots. Her two diesel engines produced 2,750 horsepower and sixteen knots on the surface; the enormous storage batteries produced 5,000 shaft horsepower for the nineteen-knot submerged speed. Oddly, the surface and submerged horsepower were almost exact opposites of the U.S. fleet sub with 5,500 surface and 2,740 submerged. The 1-200 class, the first Japanese submarines with all-welded hulls, had a test depth of 360 feet, deeper than Scorpion, less than Sterlet and Atule. Its cruising range of fifty-eight hundred miles was half that of our fleet boat. Externally, 1-203 was a thing of beauty. The deck gun, radio antenna , and bitts for securing lines all recessed into the deck before diving. The bridge contained fairing plates for each watchstander, sealing the openings before diving. Before submerging they "pulled the hole in after them," to perfect the underwater streamlining. Sacrificing safety for speed, the rounded main deck, without lifelines or handholds, appeared hazardous to walk on at sea. The underwater stabilizer fins, or "wings," extended about seventeen feet out from the pressure hull opposite the bridge. The fins created serious problems in shiphandling in close quarters. A slight miscalculation and they could slice through pilings or through the hull of the tender several feet below the waterline. The 1-200 boats were almost impos- 206 Submarine Commander sible to berth side by side without mutual interference. The Japanese moored them separately to buoys. We solved the problem by endfor -ending one of them and overlapping the forward sections as far as the fins would allow. The interior offered other surprises, mostly unpleasant. To get the power for the great underwater speed, almost the entire ship had been converted into a storage battery. Where our submarines carried 252 cells in the battery, the 1-203 carried 4,192 cells, somewhat smaller, every one plagued with problems. She had radar that couldn't tell a blip from blue cheese and a directional German-design radar receiver of high quality-far superior to the one Fred Oyhus designed on the Atule. The sonar, also German-made, was a Balkon array of fixed sound heads mounted around the bow. 1would not see this superb equipment equaled in the U.S. Navy for at least a decade to come. The engine rooms presented serious problems. Operating parts were poorly machined; many gaskets and gauges were missing. The engines were German HOR type, used in a few U.S. submarines with such poor success they required total replacement. 1-203 had a snorkel to allow engines to be used while the sub was submerged to periscope depth. Originally designed by the Dutch in the early 1930s, it was adopted by the Germans and Japanese in 1944. A poor design gave the Japanese fits, alternately pulling out the eardrums from excessive vacuum or poisoning the inside air with noxious exhaust fumes. The Americans, operating more and more on the surface late in the war, never needed the snorkel, adding it only in postwar construction. 1took special interest in the torpedo-firing system. The Japanese torpedo data computer was far simpler than ours, lacking a position keeper and much of the automation necessary for attacks in a rapidly changing situation, or against multiple targets. 1 worked with the Japanese TOC until 1 was able to make a full comparison with ours, meeting a few oddities-ours displayed a "correct solution" light when a torpedo could be fired, theirs the opposite, indicating when one could not be fired. Throughout the ship, a critical lack of spare parts, blueprints, and machinery histories immediately became obvious. Pieces of equipment were missing. These pre-electronic-era...

Share