Type U 31 submarines were double-hulled ocean-going submarines similar to Type 23 and Type 27 subs in dimensions and differed only slightly in propulsion and speed. They were considered very good high sea boats with average manoeuvrability and good surface steering.[2]
U-37 had an overall length of 64.70 m (212 ft 3 in), her pressure hull was 52.36 m (171 ft 9 in) long. The boat's beam was 6.32 m (20 ft 9 in) (o/a), while the pressure hull measured 4.05 m (13 ft 3 in). Type 31s had a draught of 3.56 m (11 ft 8 in) with a total height of 7.68–8.04 m (25 ft 2 in – 26 ft 5 in). The boats displaced a total of 971 tonnes (956 long tons); 685 t (674 long tons) when surfaced and 878 t (864 long tons) when submerged.[2]
U-37 was fitted with two Germania 6-cylinder two-stroke diesel engines with a total of 1,850 metric horsepower (1,361 kW; 1,825 bhp) for use on the surface and two Siemens-Schuckert double-acting electric motors with a total of 1,200 PS (883 kW; 1,184 shp) for underwater use. These engines powered two shafts each with a 1.60 m (5 ft 3 in) propeller, which gave the boat a top surface speed of 16.4 knots (30.4 km/h; 18.9 mph), and 9.7 knots (18.0 km/h; 11.2 mph) when submerged. Cruising range was 8,790 nautical miles (16,280 km; 10,120 mi) at 8 knots (15 km/h; 9.2 mph) on the surface, and 80 nmi (150 km; 92 mi) at 5 knots (9.3 km/h; 5.8 mph) under water. Diving depth was 50 m (164 ft 1 in).[2]
^Helgason, Guðmundur. "WWI U-boat commanders: Erich Wilcke". German and Austrian U-boats of World War I - Kaiserliche Marine - Uboat.net. Retrieved 16 March 2015.