- A.N. Other and NHSA Webmaster
- Early warships
- RAN Ships
- HMAS Platypus, HMAS Brisbane I, HMAS Sydney I
- June 1983 edition of the Naval Historical Review (all rights reserved)
- Displacement: 1,210 tons surfaced, 1,820 tons submerged.
- Length: 275½ feet.
- Beam: 23 feet.
- Draught: 14 feet.
- Machinery: Three Vickers solid injection diesel engines 3600hp/1400hp. Three screws.
- Speed: 19.5/9.5 kts.
- Radius: 5,000 miles at 12 kts surfaced.
- Armament: 6×18 inch torpedo tubes (4 Bow, 2 beam) 1 or 2-3 or 4′ gun.
- Complement: 44.
|Jl||Portsmouth Dy||1915||6/11/15||1916||Sold 26/2/24|
|J2||Portsmouth Dy.||1915||6/11/15||1916||Sold 26/2/24|
|J3||Pembroke Dy.||1915||4/12/15||1916||Sold 1/26|
|J4||Pembroke Dy.||1915||2/2/16||8/1916||Sold 26/2/26|
|J5||Devonport Dy.||1915||9/9/15||4/1916||Sold 26/2/26|
|J6||Devonport Dy.||1915||/15||/1916||Sunk 15/10/18|
|J7||Devonport Dy.||1916||21/2/17||11/1917||Sold 11/29|
The J class of submarines were designed and begun in 1915 when rumors began circulating around the Admiralty that the Germans were building a new large type of submarine with a surface speed of 22 knots. These rumors later proved false. Further Admiralty requirements called for a longer endurance and more powerful radio equipment than the E class submarines then operating, to enable the new class to operate in concert with the Grand Fleet.
The new J-Boats owed much to the experience gained with the experimental diesel driven ocean going submarine HMS Nautilus, which, however, never became operational. Nautilus was fitted with two 1,200hp diesels, 12 cylinder variants of the successful 8 cylinder 800hp diesels fitted to the E class. Nautilus had many teething problems but much valuable knowledge and experience was gained. The J class were nearly 100 feet longer than the E class and displaced twice as much. They were fitted with three each of the new 12 cylinder diesels, working on three screws and providing 3,600hp for a speed of 19½ knots when on the surface. When the first J-Boat was delivered in 1916 they were the fastest submarines then in existence. J7, the last of the class to be delivered, had a slightly different appearance to her sisters in that her conning tower was set further aft. There were also some minor hull form variations from boat to boat.
As each new submarine was commissioned she was assigned to the 11th Submarine Flotilla at Blyth, England, and the Flotilla was brought under the direct control of the C-in-C of the Grand Fleet, Admiral Jellicoe. Admiralty expectations of the new Fleet Submarines were high and the best and most experienced submarine commanders were recalled from the Baltic and the Dardanelles to captain them.
Martin Nasmith, VC, commanded J1, Courtney Boyle, VC commanded J5. The legendary Max Horton commanded J6 and other renowned officers either joined or replaced them, including Warburton, Noel Laurence, Goodhart and Ramsey. All these men, however, achieved fame while operating in the traditional submarine role alone, not hamstrung by the need to act as an intricate part of a large organised unit. In addition the J-Boats were said to be mechanically unreliable. Before long the 11th Flotilla ceased to be part of the Fleet and reverted to day to day submarine patrol work. Here they achieved some measure of success against their opponents on the other side of the North Sea.
On the 3rd November 1916 the German U-boat U30 was on her way back to base when suddenly, off the coast of Norway, both her diesel engines broke down. U20, of U-Flotilla III, the submarine which sunk RMS Lusitania, was also returning home under command of Kapitan-Leutnant Walther Schwieger and hurried to the assistance of U30. By 10pm on November 3rd they were making for Bovobjerg, Jutland, where they would be met by tugs. At about 7pm on November 4th a fog came up and at 8.20pm both boats ran aground. Apparently they had reckoned themselves more to the west than they actually were. After two hours U30 successfully worked clear but U20 remained hard aground. The High Sea Fleet Commander, Vice Admiral Scheer, immediately dispatched the Fourth Torpedo boat Half Flotilla under Korvetten Kapitan Dithmar to the scene, covered by battle-cruisers and part of the III Battle-squadron. The torpedo boats reached the stranded U-boat at 7.20am on November 5th but a strong swell was running from the south-west and three attempts to refloat U20 were unsuccessful. In spite of all efforts and the favourable high tide, she would not budge. Later, after her crew were taken off, U20 was blown up.
Lieutenant-Commander Noel Laurence had been cruising in J1 off Horns Reef when intercepted German radio signals revealed the U-boat’s plight to the British. J1 hurried to the scene and about 1pm on the 5th November he sighted the four battleships of Squadron III at a range of about 4,000 yards. Due to the heavy swell depth keeping was difficult but Laurence did not hesitate to take J1 into the attack. At one point J1 actually broke surface but due to the heavy seas she was not sighted from the German vessels. Laurence drove for the bottom at full power but at that moment the battleships came into his sights. It was now or never and Laurence fired all four bow tubes with a spread angle of five degrees. At 1.05pm SMS Grosser Kurfurst and immediately afterwards SMS Kronprinz were each struck by an 18 inch torpedo as they were executing a turn. Due to the heavy seas the torpedoes were not sighted until it was impossible to escape.
Grosser Kurfurst was hit far aft beneath her armoured belt and her port helm rendered useless. Her hull was only slightly damaged but due to steering difficulties she had to fall out of line. A short time later she rejoined the squadron at a speed of nineteen knots.
Kronprinz was struck below her belt underneath the bridge and a fairly large hole torn in her side. Because of the protection afforded by her torpedo bulkhead, though, damage was confined to her bunkers and gangway and she held her place in line steaming at seventeen knots. This was no mean achievement by Laurence and was the only occasion during the war a submarine torpedoed two capital ships in a single attack. The Kaiser initially rebuked Admiral Scheer for exposing a Battle Squadron to rescue two U-boats, but later that month when they met at Pless to discuss the U-boat campaign, the Kaiser agreed with Scheer that every step possible must be taken to maintain the initiatives gained in the naval war.
On the 12th June 1917, Kapitan-Leutnant Eitester took his U99, of U-Flotilla II, out of Heligoland bound for the waters between the Shetlands and Norway. On July 6th U99 encountered a convoy about 70 miles east of Pentland Firth. Eitester attacked and managed to torpedo and sink one of the escorting destroyers, HMS Itchen, of the River class. The next morning U99 was running on the surface some 115 miles to the east of the scene when she was sighted by the submarine J2 at a range of some 5,000 yards. J2 launched four torpedoes from her bow tubes at the U-boat and a short time later an explosion was heard. No trace, however, was found of the missing U-boat.
In April 1918 Admiral Scheer took the High Sea Fleet to sea to attack one of the Scandinavian convoys then running between Lerwick and Bergen in the hope of bringing an isolated British, or perhaps even American, Battle-squadron to action. As they proceeded through the German Bight in heavy mists on the morning of the 23rd they were sighted by J6.
Lieutenant-Commander Warburton, her commander, was unsure as to the identity of the German vessels and apparently, for reasons unknown, presumed them British. He made no attack but worse still he inexplicably failed to radio a report of what he had seen to the Admiralty. Scheer continued north as far as the latitude of Bergen without further detection. Had J6 correctly identified the Germans not only may she have torpedoed one of them but there also may have occurred another full scale sea battle in the North Sea. It was a fantastic opportunity missed. J4 was also patrolling the German Bight but sighted nothing at all.
On October 15th 1918 the J6 was running surfaced and approached a merchant vessel. The vessel, however, was the British ‘Q Ship’ Cymric and moreover she had mistaken J6 for a U-boat. At a later court of inquiry the Cymric’s Captain explained that something hanging down the side of J6’s conning tower made her letter ‘J’ look like a ‘U’, and so believing they had ‘U6’ cornered the ‘Q Ship’ opened fire. The hapless crew of J6 waved a large white table cloth from the after-hatch and from her conning tower a Morse lamp flashed ‘help . . . help’, but the misdirected fire did not slacken and more than a dozen holes were rent in the hull of J6. Only after the submarine drifted off into the mist in sinking condition was the order to cease fire given. Only fifteen of the crew of thirty-four were rescued by Cymric and only then was the tragic mistake realised.