The O-class ships were to be driven by three screws, two diesel powered and one steam. Eight MAN 24-cylinder V-configuration two-stroke diesel engines powered two Vulcan gearboxes, both of which drove the outer pair of diameter three-bladed screws. Aft of the diesel engines was a single boiler room with four Wagner high-pressure boilers that provided up to 55 atmospheres of pressure. These supplied steam for one set of Brown, Boveri & Cie turbines, which provided power for the center three-bladed screw. The O-class ships were designed to store 1,000 tons fuel oil for the high pressure boilers, and up to 4,610 tons of diesel oil for the diesel engines. This enabled a maximum range of 14,000 nautical miles at a cruising speed of 19 knots. They were designed to steam at a maximum of 33.5 knots, but were capable of up to 35 knots. The ships had two rudders each. Eight 920 kW diesel generators supplied electrical power for the ships, for a total of 7360 kW, at 220 V. The ships' main armament batteries were to have consisted of six L/47 SK C/34 quick-firing guns mounted in three twin turrets, the same Drh LC/38 gun turrets as were used on the "Bismarck"-class battleships. Two of the turrets were mounted in a superfiring pair forward, with the third turret placed aft of the main superstructure. The guns could depress to −8 degrees and elevate to 35 degrees. At maximum elevation, the guns could hit targets away. The guns had a designed supply of 630 shells, for a total of 105 rounds per gun. There were three types of shells: capped armor-penetrating, and two different high-explosive shells; all three shells weighed . The guns used a fore charge and a main charge in a brass case. This provided a muzzle velocity of 820 meters per second (2,690 feet per second). The secondary battery consisted of six L/48 SK C/28 quick-firing guns, also mounted in three twin turrets; two were placed on either side of the forward superstructure, the third was placed aft of the main superstructure, superfiring over the rear main battery turret. These guns were supplied with 900 rounds, for 150 shells per gun, and had a maximum range of .