SM UB-16 was a German Type UB I submarine or U-boat in the German Imperial Navy () during World War I. The submarine was sunk by a British submarine in May 1918.
UB-16 was ordered in November 1914 and was laid down at the AG Weser shipyard in Bremen in February 1915. UB-16 was a little under in length and displaced between , depending on whether surfaced or submerged. She carried two torpedoes for her two bow torpedo tubes and was also armed with a deck-mounted machine gun. UB-16 was broken into sections and shipped by rail to Antwerp for reassembly. She was launched in April 1915 and commissioned as SM UB-16 in May."SM" stands for "Seiner Majestät" () and combined with the U for Unterseeboot would be translated as His Majesty's Submarine.
UB-16 spent her entire career in the Flanders Flotilla and sank 24 merchant ships, about half of them British fishing vessels. The U-boat was also responsible for sinking the new British destroyer in 1917. In 1918, UB-16 was converted into a minelayer with the replacement of her torpedo tubes with four mine chutes. On 10 May 1918, UB-16 was torpedoed by the British submarine off the British east coast. Of the 16 men on board, only UB-16s commander survived the attack.
Design and construction After the German Army's rapid advance along the North Sea coast in the earliest stages of World War I, the German Imperial Navy found itself without suitable submarines that could be operated in the narrow and shallow seas off Flanders.Miller, pp. 46–47.Karau, p. 48. Project 34, a design effort begun in mid-August 1914, produced the Type UB I design: a small submarine that could be shipped by rail to a port of operations and quickly assembled. Constrained by railroad size limitations, the UB I design called for a boat about long and displacing about with two torpedo tubes.A further refinement of the design—replacing the torpedo tubes with mine chutes but changing little else—evolved into the Type UC I coastal minelaying submarine. See: Miller, p. 458.
UB-16 and sister boat comprised an order of two submarines placed on 25 November from AG Weser of Bremen, a little more than three months after planning for the class began.Williamson, p. 12. UB-16 was laid down by Weser in Bremen on 21 February 1915. As built, UB-16 was long, abeam, and had a draught of . She had a single Körting 4-cylinder diesel engine for surface travel, and a single Siemens-Schuckert electric motor for underwater travel, both attached to a single propeller shaft. Her top speeds were , surfaced, and , submerged. At more moderate speeds, she could sail up to on the surface before refueling, and up to submerged before recharging her batteries. Like all boats of the class, UB-16 was rated to a diving depth of , and could completely submerge in 33 seconds.
UB-16 was armed with two torpedoes in two bow torpedo tubes. She was also outfitted for a single machine gun on deck. UB-16s standard complement consisted of one officer and thirteen enlisted men.Karau, p. 49.
After work on UB-16 was complete at the Weser yard, she was readied for rail shipment. The process of shipping a UB I boat involved breaking the submarine down into what was essentially a knock down kit. Each boat was broken into approximately fifteen pieces and loaded onto eight railway flatcars. In early 1915, the sections of UB-16 were shipped to Antwerp for assembly in what was typically a two- to three-week process. After UB-16 was assembled and launched on 26 April, she was loaded on a barge and taken through canals to Bruges where she underwent trials.
Early career The submarine was commissioned into the German Imperial Navy as SM UB-16 on 12 May 1915 under the command of Oberleutnant zur See (Oblt.) Hans Valentiner, a 26-year-old first-time U-boat commander.Valentiner was in the Navy's April 1907 cadet class with 34 other future U-boat captains, including Werner Fürbringer, Heino von Heimburg, Hans Howaldt, Otto Steinbrinck, and Ralph Wenninger. See: On 1 June, UB-16 joined the Flanders Flotilla (), which had been organized on 29 March. When UB-16 joined the flotilla, Germany was in the midst of its first submarine offensive, begun in February. During this campaign, enemy vessels in the German-defined war zone (), which encompassed all waters around the United Kingdom, were to be sunk. Vessels of neutral countries were not to be attacked unless they definitively could be identified as enemy vessels operating under a false flag.Tarrant, p. 14.
On 3 June, two days after joining the flotilla, Valentiner and UB-16 stopped and sunk three British smacks — small sailing fishing vessels traditionally rigged with red ochre sails -while patrolling off Lowestoft.Helgason, Guðmundur. , , Retrieved 12 March 2009.—which were stopped, boarded by crewmen from UB-16, and sunk with explosives. The information on the website is extracted from On 12 June, UB-16 torpedoed and sank the 3,027 GRT British cargo ship Leuctra from the Shipwash Lightship. The information on the website is extracted from Nine days later, the U-boat torpedoed the British steamer Tunisiana off Lowestoft. After being hit, the 4,220 GRT ship's master beached her on Barnard Sands to save the cargo of wheat shipped from Montreal, but the ship was a complete loss. Tunisiana was the largest ship sunk by UB-16. In her first month of action, UB-16s totals were five ships sunk of 7,432 GRT, more than half of the flotilla's June total of 14,080 tons.Tarrant, p. 148. There were no deaths on any of UB-16s June victims.
UB-16s next two successes came on consecutive days in late July. On the 27th, Westward Ho!, a 47 GRT smack was boarded and sunk by UB-16s crew southeast of Lowestoft. The following day, the 1,821 GRT Mangara was torpedoed without warning one-quarter nautical mile (500 m) from the Sizewell Buoy at Aldeburgh. Eleven men died when the ship and her cargo of iron ore were sent to the bottom.
Although the Flanders Flotilla sank 31 ships in August, UB-16 did not add to that total. In a four-day span in September, however, she accounted for three of the eight ships sunk by the flotilla during the month. On the 7th, she sank two more fishing smacks, Emblem and Victorious, from Lowestoft.UB-16 was probably patrolling with sister boat during this time. UB-2 is credited with sinking two fishing smacks on 7 September in the same location. See: Helgason, Guðmundur. , Retrieved 12 March 2009. On 10 September, UB-16 sank the 51 GRT Nimrod in the same vicinity.
Germany's submarine offensive was suspended on 18 September by the chief of the Admiralstab, Admiral Henning von Holtzendorff, in response to American demands after German submarines had sunk the Cunard Line steamer in May 1915 and other high-profile sinkings in August and September. Holtzendorff's directive from ordered all U-boats out of the English Channel and the South-Western Approaches and required that all submarine activity in the North Sea be conducted strictly along prize regulations.Tarrant, pp. 21–22. UB-16 did not sink any vessels over the next four months, but resumed attacks on 18 January 1916, sinking three more smacks—Evelyn, Foam Crest, and Sunshine—between from Lowestoft.Helgason, Guðmundur. , , Retrieved 12 March 2009.
Second submarine offensive By early 1916, the British blockade of Germany was beginning to have an effect on Germany and her imports. The Royal Navy had stopped and seized more cargo destined for Germany than the quantity of cargo sunk by German U-boats in the first submarine offensive.Tarrant, p. 25. As a result, the German Imperial Navy began a second offensive against merchant shipping on 29 February.Tarrant, p. 26. The final ground rules agreed upon by the German Admiralstab were that all enemy vessels in Germany's self-proclaimed war zone would be destroyed without warning, that enemy vessels outside the war zone would be destroyed only if armed, and—to avoid antagonizing the United States—that enemy passenger steamers were not to be attacked, regardless of whether in the war zone or not.
UB-16s first successes in the new offensive came on 6 March when she sank the smacks Springflower and Young Harry about east of Lowestoft.Helgason, Guðmundur. , Retrieved 12 March 2009. Valentiner and UB-16 attacked another pair of ships in early April. The 653 GRT British ship Perth was torpedoed and sunk near Yarmouth on the 1st, while the Dutch sailing vessel Elziena Helena was sunk in an attack two days later east of Southwold.
On 5 April, Valentiner was succeeded by Kapitänleutnant Paul Hundius, a 27-year-old, first-time U-boat skipper.Hundius was in the Navy's April 1909 cadet class with 60 other future U-boat captains, including Johannes Lohs. Three of UB-16s later commanders—Hugo Thielmann, Günther Bachmann, and Rudolf Stier—were also members of this cadet class. See: In the first two weeks under Hundius' command, UB-16 sank two British steamers: the 2,978 GRT Robert Adamson on the 10th, and the 3,091 GRT Tregantle on the 22nd. Robert Adamson was sunk from the Shipwash Lightship while en route from Dundee to Le Havre with a cargo of props. Tregantle had sailed from Galveston, Texas, via Norfolk, Virginia, with a load of wheat for Hull, but was sunk off Lowestoft.
Near the end of April 1916, Admiral Reinhardt Scheer, the newest commander-in-chief of the German High Seas Fleet, called off the merchant shipping offensive and ordered all boats at sea to return, and all boats in port to remain there.Tarrant, p. 30. UB-16 did not sink any more ships for the next eight months.
Grand Fleet ambush attempts
In mid-May, Scheer completed plans to draw out part of the British Grand Fleet.Gibson and Prendergast, p. 97. The German High Seas Fleet would sortie for a raid on Sunderland,Tarrant, p. 32. luring the British fleet across nests' of submarines and mine-fields". In support of the operation, UB-16 and five other Flanders boats set out at midnight 30/31 May to form a line east of Lowestoft.The other five boats for the May action were , , , UB-17, and . This group was to intercept and attack the British light forces from Harwich, should they sortie north to join the battle. Unfortunately for the Germans, the British Admiralty had intelligence reports of the departure of the submarines which, coupled with an absence of attacks on shipping, aroused British suspicions.
A delayed departure of the German High Seas Fleet for its sortie (which had been redirected to the Skagerrak) and the failure of several of the U-boats stationed to the north to receive the coded message warning of the British advance caused Scheer's anticipated ambush to be a "complete and disappointing failure". In UB-16s group, only UB-10 sighted the Harwich forces, and they were too far away to mount an attack. The failure of the submarine ambush to sink any British capital ships allowed the full Grand Fleet to engage the numerically inferior High Seas Fleet in the Battle of Jutland, which took place 31 May – 1 June.Tarrant, pp. 32–33.