Plans for a shipped-based air force started soon after Hitler became Chancellor in 1933. The first plans were limited to supplying the existing battleships and cruisers with reconnaissance seaplanes. On March 12th 1934 the first requirements the future aircraft carrier was given. Within a year the design study had been completed. The model used was the British Courageous class of carriers. On June 18th 1935 the signing of the British-German naval agreement set the future strength of the German Navy at 35% of the tonnage of the British fleet applied to all classes of ships. This opened the way for building the first German aircraft carrier. Based on British tonnage of the time, 38,500 tons, this allowed for two ships of 19,250 tons. Officials were sent to England to attend the Navy Week where HMS Furious was opened for visitors but little was learned. More successful was a German Commission allowed to visit the carrier Akagi in Japan where they were given 100 copies of the blueprints of the air deck facilities. However, the Japanese neglected to tell them that the carrier was about to be completely rebuilt and the plans were obsolete.
At the end of 1935, when the design of the carrier was mostly completed, it received the consent of the commander of the navy. On 16th November 1935 the order to build the ‘A’ carrier was given to the Deutsche Werke Kiel AG. At that time most of its resources were engaged in building other warships and its slipways were occupied by ships under construction. Therefore construction was delayed until 28th December 1936 when it was possible to lay the keel on Slipway 1, twenty days after Battleship ‘E’ – the Gneisenau – had been launched from the same slipway. The slipway construction stage took two years. The ship was launched by Countess Hella von Brandenstein-Zeppelin, daughter of Count Zeppelin, on 8th December 1938 in the presence of Adolf Hitler. Work progressed during 1939 and by August it was estimated that the first tests could be carried out in June 1940 and the ship ready for service by the end of that year. When war broke out the Graf Zeppelin was 85%-90% completed. The engines and boilers were in place, the auxiliary machinery prepared though not yet installed and the 15cm guns were in place as well but lacked armoured shields.
The order for carrier ‘B’ was placed on 16th November 1936 with the Friedrich Krupp-Germania shipyard. The laying of the keel could not have taken place until the second half of 1938, after the heavy cruiser ‘J’ had been launched, because only one slipway (VIII) could accommodate the carrier. The date, 30th September 1936, given in some sources is invalid and probably a misprint. 30th September 1938 seems the most likely date. The construction of the ‘B’ carrier was intentionally slow because of the possibility of using experience gained from trials of the Graf Zeppelin in the ‘B’ construction. The planned launching was 1st July 1940 which did not take place as the order was cancelled on 19th September 1939. The ship had been finished up to the armoured deck. On 28th February 1940 Admiral Raeder ordered the dismantling of the hull. The ‘B’ carrier was never given a name. Peter Strasser is ascribed to the carrier by some sources but is entirely speculative and it is questionable that Hitler would have approved it even if it were on the list of proposed names.
After the start of the war, works on the Graf Zeppelin continued as planned for a while, but soon delays were caused by the extensive U-Boat building programme. [Carriers were always last in construction priority. Until 19th September 1939 the priority was: battleships, submarines, destroyers, cruisers, aircraft carriers.] In October 1939 Hitler allowed only the building of small ships and the continuing construction of five large ships, the Graf Zeppelin among them. It was the German conquest of Denmark and Norway that had an adverse effect on the ship’s fate. Defence of the long the Norwegian coast required many small ships and their construction became the priority. During a conference with Hitler on the 29th April 1940, Admiral Raeder proposed stopping all work on the carrier. Even if the ship was commissioned as planned at the end of that year, equipping her with guns would take another ten months, if not longer, and the installation of the fire control system several more months. (The original fire control system had been sold to the Soviet Union. In the end the AA and 15cm guns were removed and sent to Norway to be incorporated in the coastal defence system.) During a conference in July, Hitler referred to aircraft carriers saying that Germany must have “a cruiser with a flight deck”. Ludicrous as it was to start a new project when the existing carrier was almost complete, it was Hitler’s remarks that stopped all work on the Graf Zeppelin on the 12th July 1940 and the Design Bureau to prepare a design of an ‘M’ cruiser that could carry 14 aircraft. On the same day the Graf Zeppelin left Kiel for Gdynia (called Gotenhafen by the Germans). The ship remained there almost a year until Hitler’s decision to attack the Soviet Union on 22nd June 1941. Because of the treat of Soviet air raids the Supreme Command of the Navy ordered Group North to tow the ship further west by 19th June. The carrier left at noon 19th June and reached Stettin on afternoon of 21st June. There she was moored at Hakenterasse, remaining until German forces had penetrated far enough to lift the threat of air attacks. On 10th November 1941 she left Stettin to arrive a week later back at Gdynia. She was then used as a floating warehouse for hardwood under the name Zugvogel.
By the end of 1941, the crippling of the Italian fleet in Taranto, the Home Fleet’s interception of the Bismarck and especially the Japanese attack on Pearl Harbor had proved that ship-based aircraft were a fully developed and dangerous weapon. The Seekreigsleitung pressed for completion and putting into service of the Graf Zeppelin as soon as possible. The final discussion took place on 16th April 1942 at Hitler’s Wolfschanze headquarters. The results were as follows:
- Works on the hull and engines were to be completed by summer 1943.
- The only available aircraft types, adapted Bf 109 and Ju 87, required upgrading of the air facilities, especially installation of stronger catapults. Design, production and testing of these would take not less than two years so it was decided to modernize and adapt the existing catapults which would take six months. This gave the earliest possible time to complete the carrier as the winter of 1943/44. From the point of view of the Luftwaffe constructing a new carrier-based aircraft was impossible before 1946.
- The Luftwaffe would provide the Kriegsmarine ten fighters and twenty-two bombers to be used in the reconnaissance role. Designing a torpedo-bomber was opposed by Hitler who thought such aircraft were not useful.
On May 13th 1942 the decision was made to resume the construction of the Graf Zeppelin. Along with changes to the air facilities there were other alterations considered necessary as early as 1938/39 because of the developments in naval technology. The superstructure was obsolete. The existing mast had to be replaced with a heavier one fitted with a fighter command post and radars. The bridge and fire control centre covered with fragment-proof armour. A higher funnel shield was necessary to protect the fighter command post from smoke. The alterations resulted in a significant increase in weight that needed to neutralised to keep the ship stable. Bulges were added to keep the ship upright. The secondary role was to protect the ship’s interior from torpedoes. Parts of the bulges served as oil tanks. These additions improved the manoeuvrability and range of the ship. AA protection was also upgraded. The planned air component was composed of 28 Ju 87s and 12 Bf 109s.
The Supreme Command of the Navy expected that work would be completed by April 1943 with the first sea test performed in August. However, the last twelve months of construction were to be carried out at the cost of cancelling VVIIC U-boats at Deutsche Werk AG Kiel. As well as the Graf Zeppelin, five other ships were to be converted to aircraft carriers. Due to the shortage of workers and lack of material, especially steel, Hitler decided to cancel the conversion of existing warships and put the workers and material into building the aircraft carriers Graf Zeppelin, Seydlitz and Potsdam. Meanwhile, due to increasing air threat, the operation to move the Graf Zeppelin to Kiel was delayed. She finally left Gdynia on 30th November 1942. On 3rd December the convoy reached Kieler Forde and the Graf Zeppelin anchored to the Heikendorf roadstead. On 5th December she was put into the Deutsche Werk floating dock where work on the bulges started immediately. At the same time work on the engines room was started to make the two inner shafts and their propulsion system operational allowing the ship to make a top speed of 25 to 26 knots. The objective was to finish the carrier in the autumn of 1943. On 30th January 1943 Hitler ordered all capital ships to be put out of service and cancel the construction of those not yet completed. Grand Admiral Raeder described it as “the cheapest sea victory England ever won” and was the direct reason for him being relieved from duty. On 2nd February 1943 the construction of the Graf Zeppelin, on which the bulges were still being installed, was stopped for good. On April 15th Deutsche Werk shipyard were ordered to prepare the ship to be moved to Gdynia. After these preparations the carrier was towed out on 20th April, its destination now Stettin. There she was anchored on one of the forks of the Odra River and camouflaged to look like a small island. The initial plan of moving the ship to Pillau was abandoned because of a lack of adequate anchor ground. The end of the carrier came soon after the Red Army entered the territory of the Reich. First all the Kingston valves were opened and the ship settled on the bottom. Then a ten-man squad prepared the ship for blowing up with depth charges. On the 25th April 1945 at 6pm the order was given. Thick smoke issued from the funnel, proof that the charges had gone off as planned.