H - class battleship proposals The H class was a series of battleship designs for the German " Kriegsmarine " , intended to fulfill the requirements of Plan Z in the late 1930s and early 1940s . The first variation , " H - 39 , " called for six ships to be built , essentially as enlarged s with guns . The " H - 41 " design improved the " H - 39 " ship with still larger main guns , with eight weapons . Two subsequent plans , " H - 42 " and " H - 43 " , increased the main battery yet again , with pieces , and the enormous " H - 44 " design ultimately resulted with guns . The ships ranged in size from the " H - 39 " , which was long on a displacement of , to the " H - 44 " , at on a displacement of . Most of the designs had a top speed in excess of . Due to the outbreak of World War II in September 1939 , none of the ships were ever built ; only the first two of the " H - 39 " ships were laid down . What work that had been accomplished was halted ; the assembled steel remained on the slipway until November 1941 , when the " Oberkommando der Marine " ordered it be scrapped for other purposes . Contracts for the other four " H - 39 " type ships had been awarded , but no work was begun on any of them before they were canceled . None of the subsequent designs progressed further than planning stages . Initial design . The earliest design studies for " " Schlachtschiff " H " ( " Battleship H " ) date to 1935 , and were near repeats of the early designs for the ships , armed with guns . Intelligence indicating that the Soviet Navy was planning the with guns prompted the Germans to increase the caliber of the ship ' s armament to 38 cm as well on 5 October 1936 . The " Oberkommando der Marine " ( OKM ) issued staff requirements at the end of October for a ship of armed with eight 38 cm guns with a speed of . The ship ' s radius of action was to be at least equal that of the s . Design work on the ship that came to be designated H - 39 began in 1937 . The design staff was instructed to improve upon the design for the preceding " Bismarck " class ; one of the requirements was a larger - caliber main battery to match any battleship built by a potential adversary . It appeared that Japan would not ratify the Second London Naval Treaty , which would bring an escalator clause that permitted signatories to arm battleships with guns of up to caliber . By virtue of the Anglo - German Naval Agreement , signed in 1935 , Germany was considered to be a party to the other international naval arms limitation treaties . In April , Japan refused to sign the treaty ; shortly thereafter , the United States Navy announced it would arm the new s with 40 . 6 cm guns . Admiral Werner Fuchs , responsible for the staff section in the OKM that determined the operating requirements for the ship , discussed the vessel ' s design with Adolf Hitler , the leader of Germany . Hitler demanded guns larger than any possible adversary , but guns of the caliber demanded by Hitler would have required displacements of over and drafts so deep as to prevent the use of Germany ' s ports without significant dredging . Fuchs eventually convinced Hitler that the 40 . 6 cm gun was the optimal choice for the H - 39 design . In 1938 , the OKM developed Plan Z , the projected construction program for the German navy . A force of six H - 39 class battleships was the centerpiece of the fleet . Plan Z was finalized by January 1939 , when Admiral Erich Raeder , the commander of the Kriegsmarine , presented it to Hitler . He approved the plan on 18 January and granted the Kriegsmarine unlimited power to bring the construction program to fruition . Only four shipyards in Germany had slipways large enough to build the six new battleships . The OKM issued orders for construction of the first two ships , " H " and " J " , on 14 April 1939 . The contracts for the other four ships , " K " , " L " , " M " , and " N " , followed on 25 May . The keels for the first two ships were laid at the Blohm & Voss dockyard in Hamburg and the Deschimag shipyard in Bremen on 15 July and 1 September 1939 , respectively . The outbreak of war in September 1939 interrupted the construction of the ships . Work on the first two was suspended and the other four were not laid down , as it was believed they would not be finished before the war was over . The keel for " H " had of steel installed , of steel had been machined , out of of steel supplied to Blohm & Voss by that point . Only of steel had been worked into the keel for " J " , out of of steel delivered . Steel for the other four ships had been ordered and partially machined for installation , though no assembly work had begun . It was expected to resume work on the ships after a German victory in the war . The ships neither received names nor were official name proposals published . The names , which appear in several publications ( " Hindenburg " , " Friedrich der Große " , " Großdeutschland " ) are pure speculation . Especially the often mentioned " Großdeutschland " ( = " Greater Germany " ) is highly unlikely , as Hitler always feared the loss of a vessel with name of Germany ( compare the renaming of " Deutschland " to " Lützow " ) . The only hint on the names of the units were given by Hitler himself , who mentioned during documented unofficial talks , that he would propose the names " Ulrich von Hutten " and " Götz von Berlichingen " for the ships , as these names are not connected with persons of the third Reich or the country itself , so the loss would not have a significant negative psychological and propaganda effect on the German people . H - 39 specifications . Characteristics and machinery As finalized , the H - 39 design called for a ship long at the waterline and long overall . The beam was to have been with a designed draft of . At standard displacement , which was , the draft was slightly under the limit , at . With the ship fully loaded , at , draft rose significantly , to . The hull was constructed from transverse and longitudinal steel frames and featured over 90 percent welding . The hull contained twenty - one large watertight compartments and a double bottom that extended for 89 percent of the length of the keel . Four bilge keels were fitted to improve stability . The ships had an estimated complement of 2 , 600 officers and enlisted men . The ships were to be powered by twelve MAN 9 - cylinder double acting 2 - stroke diesel engines . The engines were arranged in groups of four , on three shafts , and drove three - bladed screws in diameter . Four auxiliary boilers were installed to provide backup power ; two were oil - fired and were located between the central transmission rooms . The other two , a pair of exhaust gas boilers , were placed above them . The power - plant was rated at and 260 rpm ; it provided a top speed of as designed . The vessels could have carried up to of diesel oil , which enabled a range of at , or at a cruising speed of . Armament The main armament was to consist of eight 40 . 6 cm SK C / 34 gun s in four twin gun turret s . The 40 . 6 cm ( 16 in ) gun was 50 calibers long and fired at a muzzle velocity of 810 meters per second ( 2 , 657 ft / s ) . The guns were supplied with a total of 960 rounds of ammunition or 120 shells per gun ; each shell weighed . The guns used a sliding breech block , as was typical for German naval guns of the period ; the breech was fully sealed with a brass cartridge that contained the main propellant charge . A fore charge weighing supplemented the main charge . The turrets allowed for elevation to 30 degrees , which provided a maximum range of approximately . Rate of fire was expected to be two rounds per minute per gun . Fire control radar was unspecified , but the ships , which were to have been completed by 1944 , presumably would have been equipped with an arrangement similar to that of " Tirpitz " as she was outfitted in 1943 – 44 . Several of the 40 . 6 cm guns were constructed before work on the ships was halted ; these were later employed as coastal guns , including at Battery Lindemann in France . Twelve L / 55 C28 guns mounted in six twin turrets comprised the ships ' secondary battery . These were the same secondaries employed on the and es . The turrets allowed 40 degrees of elevation and had a maximum range of . They fired a shell at a muzzle velocity of 875 m / s ( 2 , 871 ft / s ) , and were primarily intended for defense against surface threats . The ships were also to be armed with six torpedo tubes , all submerged . They were all mounted in the bow , diverging from the centerline by 10 degrees . Sixteen dual - mounted L / 65 C33 Flak guns provided long - range defense against aircraft . Unlike those mounted on the " Scharnhorst " and " Bismarck " classes , these guns were armored to protect their crews from shrapnel , debris , and strafing attacks . The new turrets also provided faster rates of training and elevation as compared to the earlier open mounts . Close - range air defense was provided by a battery of sixteen L / 83 C33 and twenty - four C38 guns . The 3 . 7 cm guns were placed in eight twin mounts while the 2 cm guns were arrayed in six " Flakvierling " quadruple mountings . The 3 . 7 cm guns were closely grouped amidships and had a single , common ammunition hoist . Historians William Dulin and Robert Garzke note that the anti - aircraft battery as designed was too weak to effectively defend against the high - performance aircraft that came into service in the late 1930s and 1940s , and speculate that " it would have been augmented before the ships were completed . " Armor The design team envisioned the H - class ships fighting at relatively close range , and therefore selected the armor system that had been used by German battleship constructors since the of 1907 . The side belt was vertical and was attached directly to the side of the hull , in contrast with the inclined armor belt placed inboard of the side wall used by American and French designers . The side belt , which consisted of Krupp cemented steel armor ( KCA ) , was thick in the central section that covered the ammunition magazines and machinery spaces . The belt was reduced to on either end of the main section ; the stern and bow were unprotected by the main belt . The upper side belt was thick . The German Navy did not preserve official estimates for the immunity zone , though Garzke and Dulin created an estimate based on the performance of the US 45 caliber gun firing a shell . The ships ' main armor would have rendered them proof against the 16 in shell at ranges between . The 16 in shell could penetrate the upper side belt at any range , however , which left the ships exposed above the waterline . The underwater protection system was broadly similar to the system employed on the . A thick torpedo bulkhead composed of " Wotan Weich " steel backed the side armor and provided defense against underwater weapons . The bulkhead was placed from the side of the hull , though abreast of the turrets and further in the bow and stern , this distance could not be maintained . The distance between the bulkhead and the side of the ship was reduced to in these areas ; the designers compensated for the reduced space by increasing the thickness of the bulkhead to in these areas . Two armored decks composed of " Wotan Hart " steel protected the ships from plunging fire and aerial weapons . The upper deck was thick above the magazines and over the machinery spaces . The main armored deck was and thick , respectively , though on the outboard sloped sections , thickness was increased to augment the protection over the ships ' vitals . Over the magazines , the sloped armor was thick ; over the machinery spaces it was 120 mm thick . Concerned with the fate of the battlecruiser at the Battle of Jutland , the designers opted to provide relatively heavy bow armor for the H - class ships . A thick splinter belt protected the bow from shell fragments . It was reasoned that direct shell hits would cause localized damage that could be better isolated than damage from splinters , which could cause extensive flooding . The main battery gun turrets were armored with thick faces , thick sides , and roofs . The rear side of the turret was thick ; in addition to the protection offered by the greater thickness , it also moved the center of gravity of the mounting to the rear , which helped balance the turret and improve its operation . The barbettes upon which the turrets sat were armored with face - hardened steel above the upper armor deck and non - cemented steel below the deck . The 15 cm gun turrets had thick faces , thick sides , and thick roofs . Their barbettes had thick armor protection . The 10 . 5 cm mounts were protected by thick gun shields . The forward conning tower had thick sides composed of KCA and thick roof composed of non - cemented steel . The rear conning tower had 100 mm thick sides and roof , KCA and non - cemented steel , respectively . Design escalation . In early July 1940 , Hitler ordered the Navy to examine new battleship designs and how wartime experience might be incorporated . A study was completed on 15 July , and contained several recommendations for the H - class ships , including increasing the freeboard and strengthening the horizontal protection . In order to maintain displacement and speed and accommodate the increased weight of the additional armor protection , the design staff drew up an informal design , known as " Scheme A . " The design removed one of the main battery turrets to save weight ; the propulsion system was also increased in power to keep the same speed as the original design . The original diesel - only system was replaced by a hybrid diesel and steam turbine arrangement . The staff also prepared a second design , " Scheme B " , which retained the fourth turret and accepted a much higher displacement . This design also incorporated the mixed propulsion system . These studies were abandoned in 1941 after Hitler decided to halt further battleship construction until after the end of the war . The design staff therefore attempted to improve the armor protection for the H - class . The 1940 designs did not form part of the design chain that resulted in the H - 41 through H - 44 designs . H - 41 . Bomb damage sustained by " Scharnhorst " in July 1941 provided the impetus for the effort to increase the horizontal protection for the H - class . The designers were confronted with a significant problem : any increase in armor could correspondingly increase the displacement and more importantly , the draft . It was necessary to maintain the full - load draft of 11 . 5 m of the H - 39 design for operations in the relatively shallow North Sea . The only option that allowed the displacement to be maintained while armor thicknesses to be increased was to reduce the ships ' fuel supplies . A 25 percent cut in range was required , which was deemed unacceptable by the OKM . It was eventually determined that since deep - water anchorages on the Atlantic coast were available , it would be permissible to allow the draft to increase . The initial redesign called for an increase of only , 40 percent of which was additional deck armor , the remainder being used for a larger - caliber main battery . One of the most significant changes was the decision to bore out the over - sized 40 . 6 cm guns to 42 cm caliber for the H - 41 design . The design staff determined that modifications to the ammunition hoists and loading equipment would be easily effected and that the original turrets could be retained . The OKM was aware that the British had settled on a 40 . 6 cm gun for the proposed ; the 42 cm gun would grant the H - 41 design a significant advantage over these new adversaries . The ships ' armament was otherwise unchanged , apart from an increased number of 2 cm anti - aircraft guns , of which there were now to be 34 . The ships ' main armor decks were substantially strengthened : the deck was increased in thickness from to and the sloped armor at the edges was thickened from to . Wartime experience with the " Scharnhorst " class indicated that the torpedo - defense system was insufficiently strong to protect the H - 39 design from underwater damage . Beam was therefore increased , with greater width added at the ends of the armored citadel to allow a greater distance between the side wall and the torpedo bulkhead . The stern section of the torpedo bulkhead was also strengthened structurally to allow it to better contain the force of an underwater explosion . A triple bottom was also included in the design , the first time a feature was used in a German warship design . The loss of " Bismarck " in May 1941 also influenced the design ; two large skeg s were added to the outboard shafts to protect them and increase support for the stern while in drydock . The rudder system was also designed with an explosive charge to detach the rudders in the event they became jammed . The finalized design was approved by Admiral Raeder on 15 November 1941 . The new design measured long at the waterline , had a beam of , and a draft of up to at full load . The increase in weight , while engine power remained constant , reduced speed to . The OKM planned to begin construction six to nine months after demobilization , initially at Blohm & Voss and the Deutsche Werke shipyard in Kiel . Deschimag , which had been awarded the contract for " J " , could no longer be used due to the increase in draft , which precluded travel through the shallow Weser . Following the completion of a new , larger dock at the " Kriegsmarinewerft " in Wilhelmshaven , work would also be done there . The increased size of the ships would have lengthened the building time from four to five years . H - 42 through H - 44 . On 8 February 1942 , Albert Speer became the " Reichsminister " for Armaments and Munitions and gained influence over the Navy ' s construction programs . Speer reassigned some members of the H class design staff to work on new U - boat s and other tasks deemed critical to the war effort . The " Schiffsneubaukommission " ( New Ships Construction Commission ) , intended to liaise with Speer and the OKM , was created and placed under the direction of Admiral Karl Topp . This group was responsible for the design work that resulted in the H - 42 type , as well as the subsequent designs . The Construction Office of the OKM formally concluded their work on new battleships with the H - 41 type and played no further role in battleship development . After the completion of the H - 41 design , Hitler issued a request for a larger battleship and placed no restrictions on gun caliber or displacement . The only requirements were a speed of , horizontal and underwater protection sufficiently strong enough to protect the vessel from all attacks , and a main battery properly balanced with the size of the ship . The results were purely study projects intended to determine the size of a ship with strong enough armor to counter the rapidly increasing power of bombs deployed by the Allies during the war . The Commission did not discuss its activities with Raeder or his successor , Admiral Karl Dönitz , or with other branches in the OKM . As the designs for the H - 42 , H - 43 , and H - 44 battleships were purely conjectural , no actual work was begun . The German Navy did not seriously consider construction on any of the designs , which were so large that they could not have been built in a traditional slipway . Indeed , the Construction Office of the OKM sought to disassociate itself from the projects , which they found to be of doubtful merit and unnecessary for German victory . The first design , H - 42 , was long between perpendiculars and had a beam of and a draft of designed and at full load . The designed displacement was and at full load rose to . The dimensions for the second , H - 43 , increased to between perpendiculars , a beam of , and design and full load drafts of and , respectively . Design displacement was and estimated at at full load . For the final design , H - 44 , the length rose to between perpendiculars , the beam increased to , and draft rose to as designed and at full load . The displacement for H - 44 was as designed and up to at full load . Details on the propulsion systems for these designs are fragmentary and in some cases contradictory . Erich Gröner notes that " some [ had ] pure [ diesel ] engine propulsion , others [ had ] hybrid engine / turbine propulsion systems , " but does not record the type and performance for these propulsion systems . William Garzke and Robert Dulin state that all three designs featured hybrid diesel / steam turbine plants , each supplying for top speeds of , , and for H - 42 , H - 43 , and H - 44 , respectively . According to Garzke and Dulin , the designs had a speed of , , and , respectively , on just diesel engine power . Both sources agree on a maximum range of at a cruising speed of . Information on the armament outfits for the designs is equally contradictory . Both sources agree on the armament for H - 44 , which was to have been eight guns . Gröner indicates that H - 42 and H - 43 were to be armed with eight 48 cm guns , while Garzke and Dulin state that the H - 42 design was to have retained the 42 cm guns from the H - 41 design and H - 43 would have also been armed with 50 . 8 cm pieces . Both works agree that the secondary armament was to have consisted of twelve 15 cm L / 55 guns and sixteen 10 . 5 cm L / 65 guns as in the previous designs , though the lighter weapons are disputed . Gröner states that all three designs were to be equipped with twenty - eight 3 . 7 cm and forty 2 cm anti - aircraft guns , while Garzke and Dulin report only sixteen 3 . 7 cm guns and forty 2 cm guns for H - 43 and H - 44 only ; H - 42 was to have twenty - four 2 cm guns . Both sources concur that six submerged 53 . 3 cm torpedo tubes were included in each design . Notes . Footnotes Citations