Nazi aircraft carrier Graf Zeppelin under construction

The Graf Zeppelin, the only German Aircraft carrier, never completed.

The German Navy started work on two aircraft carriers but only the Graf Zeppelin was launched, in December 1938. She was never completed, as the constant argument within the Nazi regime as to how best to allocate naval construction resources was to continue throughout the war. Construction was halted on 29 April 1940 because her naval guns were needed for shore based batteries in Norway, and it was believed that she would not be completed in time to play a useful part in the war. Construction recommenced in May 1942 after the potential value of aircraft carriers became more apparent following the sinking of the Bismarck and the assault on Pearl Harbour. However Hitler became disillusioned with the Kriegsmarine, and the value of capital ships compared with U-boats, and construction stopped again in January 1943.

Another view of the Graf Zeppelin

Earlier in the war:

Later in the war: