UC-Type U-Boats | Guide 469

As the first months of World War I progressed, the Imperial German Navy found itself facing what it believed to be a set of opportunities and limitations. The opportunity came in the form of the rapid advance of the German Army along the Belgian coast, which opened up a whole new set of ports that were considerably closer to the British and French coastlines than the existing German ones, and also happened to bypass much of the defensive measures that were being taken in the southwestern corner of the North Sea specifically to block German access to the Channel. The limitations came from the fact that it was believed at the time on both sides that this war wasn't going to last that long, maybe a year at the absolute most, and so building conventional U-boats to base from the new ports would clearly be foolish as they wouldn't be ready in time. The solution seemed to be the rapid construction of small coastal submarines whose limited range and payload wouldn't matter too much when they were so close to potential targets. At one point this went as far as considering a very small 80 ton submarine with a singled forward torpedo tube and only battery power. It would have to charge up alongside a pier and then carefully manage its battery if it wanted to come home again. That idea, fortunately for the German submarine crews, fell by the wayside and instead the slightly larger and more conventionally powered Type U-B coastal submarines were designed, with a specific element of the design being that they could be transported in sections by rail to then be put together at their new home port, thus bypassing any obstacles that might be encountered if they had to be built and sailed from German ports. With that design now under construction, the Navy also looked at adapting it to mine-laying purposes, resulting in the development of the Type U-C or as it would later be known the Type U-C1 submarine. This was essentially a U-B type but with practically everything forward of the conning tower replaced by six angled wet storage mine-launching tubes, each capable of holding two mines for a total of twelve. The redesign of the bow that was needed to accommodate this happened to increase drag somewhat and so the power plant and the motor were also increased in power to maintain overall speed. The new sub displaced a little bit under 170 tonnes on the surface and a little over 180 tonnes when submerged, and was initially fitted with a 90hp diesel engine and about 175hp available from the electrical motor. Speed hovered at around about 6 knots, with the sub being just faster than that when submerged, with a combined total range of around or just over 1000 miles, 80-90% of which would be accomplished on the surface and the rest would be made up of however many 50 mile dives the sub undertook. A single rifle calibre machine gun was all the armament that was available outside of the mines. By the middle of the following year though it was clear that the war wasn't going to be ending any time soon and there were a few issues with the Type UC-1 which had been identified in action. Its lack of any meaningful direct armament meant that some captains had watched targets sail merrily on past and been unable to do anything about it, and the fact they only had a single engine meant that any kind of mechanical or electrical issue left them stranded. It quickly became clear that solving either or both of these issues would result in a submarine that was far too large to be transported by rail even in sections, but with that requirement deleted the submarine could be made considerably larger, and as a result a requirement to be able to sail from German held ports all the way to Austro-Hungarian ones in the Mediterranean was added. This resulted in the Type UC-2, a much larger vessel of just over 400 tonnes on the surface and around 500 tonnes or so when submerged. While retaining the six mine launching tubes the larger size of the sub meant that each of these could carry three mines for a total of 18. It also had an 88mm deck gun fitted and three torpedo tubes were installed. Two were external tubes mounted outside the hull high up facing forward which could, at least in theory, were reloadable on the surface as there was a spare torpedo per tube mounted outside the pressure hull. There was also an internal rear-facing tube which had two reloads broken down in the aft section. The twin-shaft design meant that it could now hit 12 knots on the surface and just over 7 when submerged although the exact speed varied as the class was produced in a number of small batches with a frankly bewildering array of engines and motors that varied quite considerably in power output and combination. The UC-2 type can also be regarded as the distant grandfather of the Type 7 U-boat of WWII fame as, in a twist on the origins of the UC which was derived from the UB, the UC-2 was then adapted to become the UB-3 by reverting the bow back to a torpedo carrying version. The UB-3 would then provide much of the baseline design for the prototype Type 7 many years later. Both UC-1 and UC-2 type submarines would be modified as the war dragged on but the last in this particular line would be the UC-3 type. These were essentially modified UC-2s which had a few fixes for a few issues. The external forward tubes were moved considerably further back towards the conning tower, the 88mm deck gun was replaced by a heavier 105mm unit and the fuel tanks were made somewhat stronger. The outer casing was also changed in profile with a very pointed almost clipper style bow as had been fitted to some later UC-2s and the rest of the casing sloping downwards as it headed aft. All of these changes put together impinged on some of the minelaying tubes reducing overall capacity to 14 as only the forward two minelaying tubes could now hold three mines with the others having to revert to the shorter two mine types. Displacement rose by 100 tonnes compared to the UC-2s but otherwise performance remained fairly similar thanks to the engine and motor power also being increased. Although a lot of them were ordered only 16 would be ready before the war ended with another nine completed after the armistice. These would join 15 UC-1s and 64 UC-2s as the sum total of all small minelaying subs of the but operating these vessels came at a very high cost. Every single type UC-1 was lost with only UC-8 not actually sinking and that was because she went aground off the Dutch coast and was captured as a result. Another type UC-1 did go aground and was captured by the British but they then sank it afterwards. 72% of the UC-2s were also lost and although none of the UC-3s were lost in combat, that had more to do with the fact the first one was only commissioned in July 1918 and none of the type actually went out on an active war patrol. That's it for this video. Thanks for watching. If you have a comment or suggestion for a ship to review, let us know in the comments below. Don't forget to comment on the pinned post for drydock questions.