Schlachtschiff "J" (Grossdeutschland)
An H-39 with more logical aircraft facilities and better AA.
The H-39 design was a type of battleship proposed by Nazi Germany before the outbreak of World War II. This was basically an enlarged version of the Bismarck class, and was designed as part of the proposed Plan Z fleet.
The Bismarck class
The F - G design, a 35,000-ton battleship program started in 1932, was laid down before the Anglo-German Naval Treaty of 1935. These would become the Bismarck class, the largest battleships built by Germany, and the heaviest battleships in any European navy. Despite this they had a number of design flaws, which the admirals of the Kriegsmarine were determined to correct in their next design, the H class. In 1937, Germany's Oberkommando der Kriegsmarine (OKM) ordered a study for a new battleship class to succeed the Bismarck design.
From the beginning Adolf Hitler insisted on 50.8 cm (20.0 in) guns, instead of a 40.6 cm (16.0 in) caliber. The naval staff had difficulties in persuading him that any design mounting guns larger than 16 in was not practical. Any battleship which mounted 20 in guns would have to weigh 80,000-120,000 tons, with a length of 1,000 ft (300 m). This would also mean reconstructing German ports so as to service such a ship. Additionally a German 16 in gun design had already been developed in conjunction with the 38.0 cm (15.0 in) design. Any new design for a much larger gun would dramatically lengthen the design and construction process. Finally Hitler agreed with the H-39 design as proposed.
The H-39 class design was basically an enlarged version of the Bismarck class. The most noticeable difference was the use of two smokestacks on the H-39 class, instead of one on Bismarck. The Bismarck also used steam turbines for propulsion, while the H-39 class was designed for diesel engines, and had a 60% increase in operating range over the earlier ships. The twelve propulsion diesels would also provide a top speed of 30 kn (56 km/h), about the same performance as the battleships in other navies. The space requirements for the engines and stacks also prevented a hangar/catapult arrangement amidships as in Bismarck. The hangars for four Arado Ar 196 floatplanes were placed in the aft superstructure with rails running on either side of the aft turrets to a centerline catapult aft of turret D.
The H-class ships would have compared more favorably than Bismarck class to other battleships of the time, being superior to the older design in both armament and armor. They would have out-classed every British battleship afloat. However, the proposed British Lion class battleships, armed with nine 16 in (406 mm) guns would likely have outgunned them, and sporting an extra 85 mm of belt armor (380 mm), would have enjoyed greater protection than the H-class.
During 1941 the "H class" was redesigned ("H-41") and it was proposed to bore out the existing guns to 42 cm (16.5 in) caliber. One of the reasons behind this conversion was to give these ships a larger caliber weapon than those planned for any known Allied battleship. This and the later "H-42" never got off the drawing board. Then in late 1943, Hitler's original idea of a huge 50.8 cm (20.0 in) gunned battleship was drawn up. This was designated "H-44", but with the stress on German war production at a high level it was decided by late 1944 to abandon the project. The assembled steel was later used to make U-boats.
In 1938 OKM developed Plan Z which would enlarge the Kriegsmarine by 1945. Part of this called required a total of six H class battleships to be laid down. In August Hitler ordered that the Bismarck class be completed by late 1940 and that the construction of the H class would begin in 1939. In January 1939 the Plan Z was adopted and the order for the six H class battleships was placed.
Construction contracts were with the following Naval yards:
* Schlachtschiff "H" to Blohm + Voss at Hamburg
* Schlachtschiff "J" to Deutsche Schiff- und Maschinenbau AG at Bremen
* Schlachtschiff "K" to Deutsche Werke at Kiel
* Schlachtschiff "L" to the Kriegsmarinewerft at Wilhelmshaven
* Schlachtschiff "M" to Blohm + Voss at Hamburg
* Schlachtschiff "N" to Deutsche Schiff- und Maschinenbau AG at Bremen
Schlachtschiff "H" (Friedrich der Grosse) was laid down on July 15, 1939 and Schlachtschiff "J" (Grossdeutschland) on September 1, 1939. "K" was scheduled to be laid down on September 15 but this was postponed because of the outbreak of World War II. A hold was also placed on construction of the two ships already started. At the time that construction was frozen "H" had 14,055-tons of material ordered, 5,800-tons delivered but only 766-tons worked into the keel. There had been less work on the "J". 3,531-tons of material had been ordered but only 40-tons put into the keel.
While only ten of the four-dozen main gun barrels needed for the ships were completed, without the ships it was decided to use the guns constructed for coastal artillery. Four guns were emplaced at Battery Trondenes outside Harstad, Norway. A twin battery was built on the island of Engeløy further south, as Batterie Dietl. Three guns were set up in Hel near Danzig, as Battery Schleswig Holstein.
After extensive testing the guns were transported from Hel to Sangatte, France and set up as Battery Lindemann, from where they fired across the English Channel at Dover. Today, the Adolf Gun at Battery Trondenes is open as a museum during the summer season.
Friedrich der Grosse
Even though the H class was never completed the first ship in the class, Friedrich der Grosse remains a part of naval fiction. Several alternate history books have been written using Friedrich der Grosse, and she has appeared in several naval wargames as well.
During World War II itself Time Magazine featured several articles in 1940 and 1942 about German capital ships. Friedrich der Grosse is mentioned as one of these ships.