Plan Z - Nazi Shipbuilding Plans (2024)

Germany was permitted by terms of an agreement with the British on 18 June 1935 to build up to 35 percent of the latter's total naval tonnage and 45 percent of Britain's submarine tonnage. Following as it did on Hitler's denunciation of the military limitations imposed on the Reich by the Versailles Treaty, the naval agreement constituted tacit British consent to German rearmament. The British were temporarily reassured by the German agreement to limit the size of the Reich's new navy. However, the French were distressed by the increase in German naval power, and a wedge wras driven in the Allied front.

In May 1938 Hitler told the Commander-in-Chief, Naval Forces, of the strong possibility of war with Britain but that there was no immediate prospect of conflict. In September 1938 a naval committee was established to make recommendations for increased shipbuilding and reassessment of German naval strategy in the event of war with Britain. The Z-Plan, a nine year construction program for the period 1939-48, was the result. The Naval Building proposal, Plan Z, authored by Admiral Raedar, and approved by Hitler, an eventual force of thirteen battleships and battle cruisers, four aircraft carriers, fifteen panzerschiffe, twenty-three cruisers, and twenty-two large destroyers. The Z Plan envisioned envisioned a balanced fleet of both surface vessels andsubmarines (only 233), to accomplish the dual task of waging a campaign against both the British merchant fleet and the British naval vessels protecting them.

The modified Z Plan of 1939 would have seen the completion of the two battleships under construction (Bismarck and Tirpitz) to an interim design, as well as three heavy cruisers (Admiral Hipper, Blücher and Prinz Eugen), plus a further two launched in 1939, before the major construction work began. The plan was then to have the majority finished by 1945:

• Four aircraft carriers
• Six H Class battleships
• Three "O Class" battlecruisers
• Twelve "Kreuzer P Class" Panzerschiffe
• Two Hipper Class heavy cruisers (Seydlitz, and Lützow)
• Four "M Class" light cruisers
• Two "Improved M Class" light cruisers
• Six "Spähkreuzer Class" large destroyers

The first work saw construction begin on the aircraft carrier Graf Zeppelin in 1936, with a second planned to begin in 1938. In mid 1939, following the launch of both Bismarck and Tirpitz, the keels of the first three improved battleships were laid, while orders were placed for the modified Messerschmitt Bf 109 fighters and Junkers Ju87 dive bombers for the aircraft carriers. The concept of Plan Z was based on a classic guerre de course to achieve the strategic task of the navy-destruction of the British merchant navy. Under the "double-pole" approach two small but powerful battle groups, each formed around battleships plus a single aircraft carrier and screened by diesel-powered light cruisers and destroyers, maintained local sea control in the North and Norwegian seas. The proposed battle groups represented a major departure from conventional naval organization and operational concepts. Single high-endurance warships would engage in distant operations against British commerce. Aggressive and wide-ranging operations against shipping would force the British to implement a global scheme of convoys, in such numbers as to stretch Royal Navy escort forces to create exploitable opportunities for German surface forces. The force structure goals of the Z Plan, to have been reached in the mid-1940s, were preempted by the outbreak of war, and the Germans were accordingly unable to implement fully the double-pole strategy.

From the moment Raeder assumed command of the German navy, high endurance became a design goal for new Kriegsmarine warships. German warship endurance during the early interwar period was double that of the First World War. Warships designed after 1938, when planning centered on action against Great Britain, had even greater endurance.

In January 1939 Hitler approved the Z-Plan building program and subsequently abrogated the Anglo-German Naval Agreement, with the understanding that he would take all the necessary diplomatic actions to prevent war prior to 1944. The invasion of Poland on 1 September 1939, made Hitler's intentions for immediate war crystal clear and the Z-Plan was no longer a viable option. The naval building plan shifted focus to the rapid completion of the two battleships and cruiser already under construction. The submarine building program was accelerated to produce twenty to thirty U-boats per month.