PTC Motor Boat - Subchaser
By the spring of 1915 the submarine situation had become so grave that the Lords of the Admiralty decided that something had to be done and done quickly. From the frequent and audacious sinkings, some of them at the very mouths of English harbors, and the toll already taken from the British fleet itself, it was plain that a large and powerful Navy was not the solution of the problem. Neither were the thousands of trawlers, and other auxiliary craft patrolling the waters of the British Isles, able to check the growing menace.
80-Foot Submarine Chaser - M.L. Motor Launch
The earlier patrol boats for England - the five hundred and fifty 80-footers, known as the M.L.'s, did varied and valiant service during the later years of the war. These boats were the forerunners of our American Chasers and it was upon the results of their performance, to some extent, that American boats were designed. The submarine chaser is simply a boat whose success depends on four factors, and these are (a) how fast she can go; (b) how light her draft is; (c) how well she is armed , and (d) how fast she can be built. Two kinds of these chasers have been built, and both have shown their real worth. The first is known as the 80-foot submarine chaser. Over 550 of these craft were built for England and sent over to operate against the U-boat in British waters.
The British Admiralty ordered five hundred additional Chasers, the whole lot to be delivered complete and in running order by November 15, 1916. Five hundred fifty boats in as many days.
The first consideration was the speed, which was to be 19 knots minimum when fully loaded. The second consideration was the large cruising radius specified, to attain which the fuel capacity had to be over 2000 gallons, which meant a weight of 12,000 pounds for fuel alone. Besides this, it was necessary to allow for a deadweight of 20,000 pounds, the equivalent of the weight of the guns, ammunition, water and supplies. The next consideration was seaworthiness, for it was specified that the boat should be able to maintain station in any sort of weather. And finally there was the problem of rapid construction which eliminated at the start any possibility of the use of such features as double planking and the like. A type of construction had to be decided on which would be within the limits of complete standardization. Further to limit the designer, the size had to be such that the boats could be carried on the decks of steamships and for this reason 75 feet at first was decided on as the length of the boats.
They were powered with gasoline engines and were built just about like the high-speed pleasure boats that were common on the American side of the Atlantic, that is, they had a three-quarter cruising cabin and cockpit. They are very seaworthy, and the powerful gasoline engines installed in them give them speed enough to outrun the fastest submarines that had yet been built. Each one carried a rapid-fire gun of the 3-inch type.
It was calculated that the cruising radius at full speed with 2000 gallons of gasoline would be 800 miles, although at 15 knots it would be possible to cover 1000 miles and at 11 knots, 2100 miles. When the order for 500 boats came in shortly after the completion of the first sample from which the rest were standardized, it was decided to lengthen out the boat from 75 to 80 feet. The body plan was kept the same but it was found that by loosening up the interior arrangement more comfortable quarters were obtained without the slightest reduction in speed.
Crowding 500 horsepower into even an 80-footer means that there was not going to be able to treat the crew very generously in the matter of living quarters with what space is left. Up forward, in a length of twenty feet, seven men lived and slept in a fo'c's'le considerably smaller than that of a Gloucester fisherman. The officers' quarters in the stern were divided into a ward room "where two can turn around and three becomes a crush" and a pretty decent sized stateroom with two bunks.
The fighting equipment of the M. L. consisted of a short calibre 3-inch gun using a shell weighing in the neighborhood of 13 pounds. It was a short gun with a long recoil and while the range was much less than that of a standard Navy gun of the same bore, it required a smaller gun crew and was successful for these small quick-acting vessels on which the ability to shoot a large shell was more to be desired than range.
But more important than the deck gun was the depth bomb with which the little fighters put the fear of Gott into the biggest U-boats. This highly-revered shipmate known as the ashcan, contained 250 pounds of T. N. T. and could be set to explode at any predetermined depth. It was the depth bomb that sealed the fate of the submarine. With it, it was not necessary actually to hit the submerged target; merely to explode the can within 30 or 40 yards of the sub frequently was sufficient to cause the starting of a seam or the disarrangement of the storage battery or other interial mechanism.
In order to fight the submarine at close range the early boats carried what were known as lance bombs - 14 pound bombs on the end of 40-foot handles. These were designed to be thrown much as an athlete would throw a hammer and, needless to say, they were handled and treated with the utmost reverence. Later they were omitted from the equipment.
The M. L.'s made good. Not only in the actual work of patrolling for submarines but in countless other ways as well - sweeping for mines in the channels ahead of ships, convoying merchant vessels, towing the deadly Q type paravane for lurking subs, laying mines, co-operating with air craft - in the Channel, in the North Sea, in the Mediterranean, at the Dardanelles and in the Adriatic. The ubiquitous M. L.'s did what the other ships could not do and did it well. Their work attracted the attention of the French and Italians, and large orders were placed for Standard motors and in many cases for completed boats which brought the total number of M. L.'s up to 720.
90-Foot Submarine Chaser
The only fault with the 80-footer was that its small size made it impossible to store away enough fuel to give it a large cruising radius, and so a new type of submarine chaser was built which was 90 feet long. Its had a speed of 25 knots. The craft was armed with a battery of two 3-inch guns mounted on the fore and aft decks. The larger size of this chaser makes it easy for it to cruise for long distances, while its speed is 8 knots faster than that of the fleetest submarine and this made it a foe that was truly to be feared.
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