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THE ‘K’ BOATS – ‘K’ as in Calamity

This  is  a  story about a  class  of steam driven submarines   the British laid down in 1915.Seventeen of the “K” class were commissioned. At that time and for long after the first world war the existence of this class was a closely held secret. They were by far the largest, the fastest, and the most technologically advanced submarine of that time.

The “K” boats were almost equal to our Fleet boats of WW II, but the “K” boats could make 24 knots on the surface while the top speed of the Fleet boats was about four knots less.

This speed was made possible by a power plant of 10,000 horsepower,about half again that of any submarine until the Nautilus, some forty years later.

The “K” boat had two steam boilers, two geared turbines, a large battery and four electric motors. As a most fortunate afterthought. a small diesel engine was added which enabled many of the boats to get home when the boiler room was flooded. This power plant was a brilliant design for a surface ship. But for a submarine there were just “too damned many holes”. There were two funnels, each five feet high, two feet in diameter and hinged to lie flat when submerged. In addition there were four air intake boles of over three feet in diameter.

The valves for these holes were operated mechanically, a tremendous advance in the “state of the art”, but one for which there had been no operational experience.

Admiral Jackie Fisher, the First Sea Lord at the time the “K” boats were being considered, wrote “The most fatal error imaginable would be to put steam engines in a submarine.” But technology was in the driver’s seat at the Admiralty. The apparent need for a fast submarine to support the fleet overcame all arguments Jackie Fisher and the submariners could muster.

Prior to 1910 the French had built thirteen steam submarines with reciprocating engines. Jane’s Fighting Ships commented on this class: “Their great defect is that a great deal of inconvenient beat is given out when they submerge and the actual time of submergence is rarely under ” The diving time of the later “K” boat was just under 5 minutes in contrast to one minute or less for diesel submarines.

No one was more convinced that a steam submarine was a stupid idea than the stoker in the boiler room. He stood watch no further than a few feet from the boiler. The heat and the noise were a taste of hell.

In any kind of sea the stoker wore oilskins to protect himself from the great quantities of water that poured down the ventilators. Often this water caused flarebacks which killed several stokers and singed eyebrows on most of the others and flooded boiler rooms caused many unexpected dives. Several “K” boats had boiler room fires from the oil that floated on top of the water.

At the sound of the diving hooter the stoker shut off the oil to the boilers, stopped the fans and pumps, and lastly clambered over the boiler to shut off the steam. Then, in a state of collapse from the beat, be staggered through the twin doors or the airlock and sealed off the boiler room.

The large flat foredeck of the K-boat tended to cause it to dive unexpectedly when at high speeds in heavy seas. It also caused a loss of control when diving.

As a boy or 18, the future King George V was taken for a dive in K-3 soon after it was commissioned.   Control  was lost as  the boat submerged in 150 feet or water. The bow dug into the bottom and the tail rested well out of the water with the screws spinning. After 20 minutes the boat was able to free itself and come to the surface. Luckily the water in the North Sea was shallow. Otherwise the K-3, as well as many other K-boats would have been lost in uncontrolled dives.

Soon afterwards, K-3 was again embarrassed. While steaming at ten knots with a fresh breeze on her beam she shipped water down the funnel. This extinguished both boilers and before the vents could be closed the boiler room was filled with water. She returned to port on her diesel engine.

The Admiralty attributed this casualty to “personnel error” and stated that repetitions would be prevented with “experience gained.” The Admiralty was so committed to the “K” class that design faults were never admitted — it was always human failure. Correction of critical weaknesses were not considered, while many boats and lives were lost in repeated but correctable casualties.

However,    there      was    one  instance where         the Captain was  not  considered  at  fault. The K-~ was on an anti-submarine patrol in the Orkneys. To protect his boat from the heavy seas the Captain took refuge in a cove. The awkwardness of the K-boat caused it to go aground. But the Captain later testified that a rat bad eaten the relevant part of ~is chart — and he got away with this excuse.

The “K” boats were classified as “submersible destroyers.” They were fitted with depth charges which were never used. In addition to depth charges they carried four bow and four amidship torpedo tubes with two more tubes topside in the superstructure. On the main deck were two four-inch guns and one three-inch gun for anti-aircraft firing — a respectable armament even for a destroyer of that time.

The “K” boat was designed to be a tactical unit of the Fleet. In a battle between two fleets the K-boat was to use its high speed to get ahead of the enemy fleet and dive for attack.

This appeared practical for war games, but in the real world the limitations of the “K” boat made this an expensive non-solution. In fact the only time a “K” boat engaged the enemy in World War I was in an attack on a “U” boat when its torpedo hit but did not explode.

The “K” boats were said to “have the turning radius of a battleship, the speed of a destroyer, and the bridge of a picket boat.”

Towards the end of the war, the misfit between the K-boat and other units of the Fleet was illustrated in living color in what was to be known to the submariners as “The Battle of Hay Island.”

A practice deployment of the  Fleet was   ordered on   31  January,  1918.Part  of  the  fleet  was  to deploy  from  the  Firth of Forth.This   detachment consisted of three battleships, four battle cruisers, some 25 destroyers, and two Flotillas of “K” boats. In all there were forty ships in a line ahead formation that stretched for 30 miles. There were four boats in one submarine flotilla and  five  in the other.Each flotilla  had  a  light cruiser as its flotilla leader. Ships were stationed 400 yards apart and speed in the channel was   16  knots.The flag was  in  the  lead  ship,   a cruiser. Astern was a flotilla of submarines which was followed by a squadron of battle-cruisers, then another flotilla of submarines and finally a squadron of battleships. The larger ships were surrounded by destroyers.

Deployment started after dark. That afternoon a seaplane had sighted a submarine off Hay Island which was at the harbor entrance. The flag ordered speed to be increased to 22 knots after leaving the harbor defenses.

All ships were darkened except for a blue stern light — to be shone at half brilliance. Soon after departure a light mist decreased visibility to a point where seeing these blue lights was a sometime thing.

As the first flotilla of submarines left the harbor defenses their speed was increased to 22 knots. Immediately afterwards the navigation lights of several unknown ships were suddenly seen dead ahead of the leading “K” boat. These unknown ships were actually a formation of mine-sweepers which had not been informed of the fleet deployment.

The K-17 went ‘hard a starboard.’ The rudder jammed and remained jammed for 6 minutes. Navigation lights were lighted and after the rudder was free the K-17 attempted to rejoin the unseen formation, However in the mist K-17’s running lights were not seen by K-22 until too late and she rammed the 17.

Both    ships flooded  forward,  A message was sent  out and signal  flares were  fired continuously. But with no effect. Fifteen minutes later the battle-cruiser squadron roared down on  the  two sinking boats,  One   destroyer passed but 10 feet from the 22. That was soon followed by a battle-cruiser which swung to avoid but hit K-22 with her stern. Thirty feet of tanks were swept off the K-22 but she was able to remain afloat.

Twenty minutes after the first collision, their flotilla leader, the cruiser ITHURIEL, had finally decoded their distress message and, with the remaining three subs following, turned back to the area of the collision. A message was sent to the oncoming battle-cruisers — but for some reason this was never received,

ITHURIEL  and  her  subs  actually  steered head- on to the battle-cruiser formation. Eventhough the ships were passing each other at forty knots in low visibility, by some miracle and much weaving there were no collisions.

Following the battle-cruisers came the other submarine flotilla led by the cruiser FEARLESS. They also had no knowledge of the situation. FEARLESS saw navigation lights of unidentified ships ahead but these indicated that FEARLESS bad the right-of-way.FEARLESS kept  her course and speed until it was too late. K-17 was trying to change course but her sluggish turning circle was just not adequate. At the last minute FEARLESS tried to avoid but her bow went deep into the K-17 just forward of the conning tower. K-17 sank seven minutes later. FEARLESS was followed by K’s 4, 3, 6 and 7 in that order. Each was unaware of what was happening. When FEARLESS stopped, K-4 slowed, turned on navigation lights and swung to port.  The  next ship, K-3, also came left  and barely missed K-4. The third ship astern, K-6, turned right to avoid K-3 and rammed the unseen K-4 with such force that her bow was locked in K-4’s hull. As K-4  sank  it was carrying K-6  down with her. At the  last  moment  K-6     wrenched    herself free. (Serving on board K-6 was Midshipman Lord Louis Montbatten who later had other experiences with sinking ships.) Next in line, K-7, swung right to miss K-6 but ran over the spot where K-4 was sinking. K-7 was able to miss the conning tower, the only part of K-4 still showing, but scraped over the sinking bow.

As the battleships and their destroyers went through this area at 22 knots there were several near misses but no more collisions. However many lives were lost as ships ploughed over the spot where survivors were in the water.

The Court of Inquiry placed total blame on five of the submarine captains. The Captain of K-22 was held responsible for being rammed by INFLEXIBLE because the K-22 lay on INFLEXIBLE’s track. This in spite of the K-22 being partially flooded and standing by the K-14. At  this  point, work was  stopped  on  the eight remaining   K-boats. But  technology was still  in the driver’s seat. Three of the hulls were completed with diesel engines and each was fitted with a 12-inch battleship gun. They were named the “M” class and called “submersible monitors.”

Jane’s Fighting Ships  reported:  The  gun  is loaded and  laid  to a high angle. The  boat  is  then dived to 20 feet leaving the muzzle above water. There is a bead on the gun’s muzzle so that the gun can be sighted by periscope and fired. Reports are not available on M-1’s operations so that its performance is a matter of conjecture.”

Of the 20 “K” boats, which includes the three converted to “M” boats, one sank on trials, four were lost in collisions, two disappeared and one sank alongside a pier. There were sixteen major and countless smaller accidents. The loss of life was appalling.

In  summary: No opportunity came  to test these ships as a tactical unit in war. Many were the times they went to sea with the Fleet and as tar as keeping up with the big ships and taking tactical positions they were an unqualified success. But it must be remembered that the K’s were asked tor by the Grand Fleet; they were not a product or the submarine branch nor were they the submariner’s idea or what a submarine should be.

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