overboard. Machinery The Deutschland-class ships were equipped with two sets of four 9-cylinder, double-acting, two-stroke diesel engines built by MAN. The adoption of an all-diesel propulsion system was a radical innovation at the time and contributed to significant savings in weight. Each set was controlled by transmissions built by AG Vulcan. The engines were paired on two propeller shafts, which were attached to three-bladed screws that were in diameter. Deutschland was initially fitted with diameter screws, before they were replaced with the larger screws. The engines were rated at and a top speed of . They did not meet the expected shaft-horsepower on trials, though they did exceed their design speeds. Deutschlands engines reached and , and Admiral Scheers engines reached and . Horsepower figures for Admiral Graf Spee are not recorded, though her top speed on trials was . Deutschland could carry up to of fuel oil, which provided a maximum range of at a speed of . An increase in speed by one knot reduced the range slightly to . At a higher speed of , the range fell to . Admiral Scheer carried and had a correspondingly shorter range of at 20 kn. Admiral Graf Spee stored of fuel, which enabled a range of . Electricity was supplied by four electric generators powered by two diesel engines. Their total output was 2,160 kW for Deutschland, 2,800 kW for Admiral Scheer, and 3,360 kW for Admiral Graf Spee, all at 220 volts. Steering was controlled by a single rudder. Armament The three Deutschland-class ships were armed with a main battery of six 28 cm SK C/28 guns mounted in two triple turrets, one on either end of the superstructure. The turrets were the Drh LC/28 type and allowed elevation to 40 degrees, and depression to −8 degrees. This provided the guns with a maximum range of . They fired a projectile at a muzzle velocity of . The guns were initially supplied with a total 630 rounds of ammunition, and this was later increased to 720 shells. The secondary battery comprised eight 15 cm SK C/28 guns, each in single MPLC/28 mountings arranged amidships. These mountings allowed elevation to 35 degrees and depression to −10 degrees, for a range of . They were supplied with a total of 800 rounds of ammunition, though later in their careers this was increased to 1,200 rounds. These shells weighed and had