An item referred to the German magazine Schiffbau dated 7 November 1928 which doubted the ufficient fighting value of the British O-class submarines. The German conclusion came to this conclusion based on what the The Engineer published. With a surfaced speed of 15 miles and just 1-10,2cm gun for submerged actions was the fighting value was just little if compared with modern submarines of other navies with a similar displacement of 1.345 (surfaced)-1.805 (submerged) tons, a minimum surfaced speed of 20 miles and an artillery armament of 2-5 15cm guns. The magazine calculated the total eight of the armament included the 8 torpedo tubes each with 2 torpedoes to be around 56 tons or around 4% of the displacement. This was regarded extreme little and hardly a reason for building such an expensive submarine. For modern submarines of other navies was that around 20% including armour for the conning tower/superstructure. The Dutch magazine did not fully accepted the criticism of the German magazine while nothing was said about stability, range, living accommodation, diving qualities and so on. But the limited surfaced speed was indeed a great disadvantage for a modern submarine. The Engineer protected against the German criticism although not able to refute the two major advantages which were also signalled by the Dutch editor.
