In 1935, Erich von Manstein of the German Army General Staff, in a letter to General Ludwig Beck, described the idea of building assault artillery to support attacking infantry units. Five prototypes of the "zero" series were manufactured in 1937. Early modifications from Ausf.A to Ausf.F/8 were produced until December 1942.
Time for the successive autoreloading of each shell into the magazine.
The improved system allows the time to be decreased for autoreloading the next shell upon firing the loaded shell when the corresponding indicator is displayed
Characteristics are specified for Siege mode.
The technical characteristics are displayed for the charged turbine mode.
Characteristics are specified for Rapid mode.
Reload time of the first and second guns on double-barreled vehicles.
Characteristics are specified for vehicles with crews trained to 100%.