Shortly after the armistice, the author witnessed the surrender of the German submarine fleet and subsequently inspected 40 of the 170 submarines first surrendered. He also inspected 185 submarines in Germany. Practically all the engines were of the Machinenfabrik Ausburg-Nürnburg four-cycle Diesel type, of 300, 550, 1200 and 1750 hp. There were but five Krupp two-cycle engines. Brief comment is made regarding the design of these engines.
The author, who supervised the dismantling of the German submarine U-117 at the Philadelphia Navy Yard, gives a detailed description of its engines, which were of the 1200-hp. type. This includes comments regarding materials, design details, valve mechanism, starting and reversing gear, lubrication, cooling and accuracy of workmanship. The air-compression system and some of its auxiliaries are outlined.
In conclusion, the author believes that the Diesel engine is not a cheap product and cannot be made cheaply and run with any great success or reliability. He is confident that the Diesel engine is past the experimental stage and that it is a practical proposition.