U-27 class submarine may refer to:
The U-27 class was a class of eight submarines or U-boats built for and operated by the Austro-Hungarian Navy (German: Kaiserliche und Königliche Kriegsmarine or K.u.K. Kriegsmarine) during World War I. The class was based upon the German Type UB II design of the German Imperial Navy and was constructed under license in Austria-Hungary.
After the Austro-Hungarian Navy had filled its most urgent needs for submarines after the outbreak of World War I, they selected the German Type UB II design for its next group of submarines in mid 1915. Orders for the first six boats were placed in October 1915 with the Austrian firm of Cantiere Navale Triestino and the Hungarian firm of Ganz Danubius. Two more boats were ordered in 1916, bringing the class total to eight.
The boats were just over 121 feet (37 m) long and were armed with two bow torpedo tubes, a deck gun, and a machine gun. For propulsion they were equipped with twin diesel engines for surface running and twin electric motors for subsurface movement. Although the class was based on the German design, the Austro-Hungarian U-boats were heavier and slightly faster underwater, but less heavily armed than their German counterparts
U-27 may refer to one of the following German submarines:
German submarine U-27 was a Type VIIA U-boat of Nazi Germany's Kriegsmarine built for service in World War II. Her keel was laid down in November 1935 in Bremen. She was commissioned in August 1936 with Korvettenkapitän Hans Ibbeken in command. Ibbeken was relieved on 4 October 1937, by Johannes Franz, who commanded the boat until 6 June 1939 when Hans-Georg von Friedeburg assumed command for barely one month. He was relieved on 8 July again by Johannes Franz, who commanded the boat until her loss on 20 September 1939.
U-27 had a very short career, with only one war patrol and only two enemy ships sunk. Following the sinking of two British trawlers, Davara on 13 September and Rudyard Kipling on 16 September, U-27 was hunted down and sunk west of Lewis, Scotland, by depth charges from the British destroyers HMS Fortune, Faulknor and Forester. All 38 crewmen survived and were made prisoner for the remainder of the war.
U-27 was ordered by the Kriegsmarine on 1 April 1935 as part of Plan Z and in violation of the Treaty of Versailles. Her keel was laid down in the AG Weser shipyard in Bremen as yard number 908 on 11 November 1935. After about nine months of construction, she was launched on 24 June 1936 and commissioned into the Kriegsmarine as the second Type VIIA submarine, (after U-33, which was commissioned a few months earlier), on 12 August under the command of Korvettenkapitän Hans Ibbeken.
SM U-27 was a German Type U-27 U-boat built for service in the Imperial German Navy. She was launched on 14 July 1913, and commissioned on 8 May 1914 with Kapitänleutnant Bernd Wegener in command.
On 18 October 1914, the British submarine HMS E3 was torpedoed and sunk in the North Sea by U-27. This was the first action in which one submarine sank another.
HMS E3 had sailed from Harwich on 16 October to patrol off Borkum in the North Sea. On 18 October, E3 spotted some German destroyers ahead but was unable to get into a position to take a shot at them. Unable to pass them, Commander Cholmley retreated into the bay to wait for them to disperse. As he did so, he failed to see that the bay was also occupied by U-27, under Kapitänleutnant Bernd Wegener.
Wegener was surfaced and patrolling between the Ems and Borkum when at 11:25, an object resembling a buoy was spotted where no buoy should be. Suspecting a British submarine, U-27 immediately dived and closed the object. Although ‘conned down’, the number 83 was clearly visible on the conning tower of the British boat, now identified as such beyond reasonable doubt. Wegener tracked the submarine for two hours until able to approach ‘up sun’. He noted that the look-outs were staring intently in the other direction, towards the Ems. When the distance had closed to 656 yd (600 m), two G6 torpedoes were fired by U-27. Detonation followed 12 seconds later, and E3 sank immediately. The KTB records that men (probably the look-outs from the bridge) were visible in the water but fearing a second British submarine might have been lurking nearby, U-27 dived and withdrew. 30 minutes later, the U-boat returned to the scene to search for evidence and possible survivors but without success. All 28 members of E3's crew were lost.