“NORDENFELT II.” AT CONSTANTINOPLE.
During her trials Nordenfelt I. hardly did herself justice, but nevertheless in the beginning of 1886, she was bought by the Greek Government, and in April, 1886, trials took place in the Bay of Salamis, when Mr. Nordenfelt’s agent carried out the various conditions imposed.
Shortly after the first boat had been bought by Greece, Turkey ordered two submarine boats (Nordenfelt II. and III.) from the inventor. Both boats were sent to Turkey in sections, but only one was assembled and tested. In 1887 it underwent trials at Constantinople, which were witnessed by the Sultan himself, who expressed himself highly satisfied with the performance of the boat.
Nordenfelt IV.
Mr. Nordenfelt’s fourth vessel was built by the Barrow Ship Building Company, the machinery being supplied by Messrs. Plenty & Sons, Newbury.
The principal dimensions were: Length, 125 feet; diameter, 12 feet; displacement fully immersed, 245 tons; in light surface condition, 160 tons. The engines turning the main propeller were especially designed for using steam at varying pressures, and indicated 1,000 h.p. when working with steam at a pressure of 150 lbs. At that power her estimated speed was 15 knots. Submerged, her speed was 5 knots. Fourteen auxiliary engines were carried for driving air circulating and feed pumps for steering and sinking. In the middle was the entrance to the stokehole through a scuttle 4 feet in diameter. Fore and aft of this scuttle were two funnels, and about 30 feet from the stem and stern of the boat were the conning towers, 2 feet high and of the same diameter. They were of 1–inch steel and were considered perfectly impervious to any shot which in warfare would ever be directed against them. In the forward tower were placed at the hands of a commander means of controlling every motion of the vessel. The boat was divided into five compartments: (1) The torpedo chamber containing two tubes; (2) Quarters for four officers; (3) The boiler room; (4) The engine room; (5) The men’s quarters, cooking galley, stoves, &c. The crew consisted of nine men all told; 35 tons of cold water were carried in the tanks; and 27 tons of hot water in the boilers. These latter were expected to store sufficient heat for a run of 20 knots under water. The coal bunkers held stores of coal which, at a speed of 8–9 knots, could drive the boat a distance of 1,000 miles. Should it be necessary to transport her to a greater distance, her water tanks could be filled with coal, enabling her to steam 2,500 miles. Two vertical propellers, one forward and one aft, kept the vessel submerged and overcame the retained force of buoyancy (500 lbs.). The boat was lighted by candles; without any special provision of air it contained enough for a crew of nine men for about six hours.
Nordenfelt IV. made her passage from Barrow-in-Furness to Southampton through some heavy seas, and during the voyage she was tested by her commander in every wind and every condition of wave and sea, and she proved that she was capable of being manœuvred in any weather, however bad.
On the 26th of May, 1887, she underwent her first examination before a body of critics, composed for the most part of skilled, experienced scientific officers of both branches of the Service. She was first run with nothing above water save the two conning towers and a few inches of her back, at the rate of about six miles an hour. The time occupied by the trial in the awash condition was 1½ hours, and at the end of the time a sufficiency of steam was stored up in the boilers to drive her a distance of about 24 miles. On the pumps being put in motion, some 20 tons of water were pumped out in eight minutes. The funnels were then fixed, the fires relighted, and the Nordenfelt was soon making 15 knots on the surface.
On December 19, 1887, a semi-official trial of the Nordenfelt took place, when she manœuvred successfully both on the surface and submerged, but no attempt was made to fire the torpedoes.
“The neutral tint she was painted,” wrote the special correspondent of the Engineer, “rendered her almost invisible at the distance of even a few hundred yards, while as a target she presented nothing to attack save the two conning towers and a few inches of her turtle back, and as these were of great strength and rendered still more invulnerable by their shape, it is all but certain that no gun carried on any other torpedo boat would ever do her the slightest injury, while she at the same time possesses the enormous advantage of being able to attack without smoke, or fire, or noise. Indeed, given these advantages of a minimum of target and a total absence of noise and smoke, we fail to see what more could be desired in any vessel of war.”