…Late 1939 saw it become apparent to most powers that a major war was coming and thus the naval buildups that had been underway since the mid 1930’s went into a fever pitch…
…On September 1st 1939 Hitler gave the order that with war imminent no new vessels larger than a light cruiser be laid down, and then only those of the smaller type Germany had planned, rather than the pseudo heavy cruisers that were under consideration. Construction on larger vessels would continue, including the very recently laid down battleships Albrecht von Wallenstein and Dietrich von Bern. Instead construction of light units, the large torpedo boats/small destroyers of the Elbing class, their 700 ton coal powered minesweepers and especially their U-Boats increased. The latter had been deliberately held down to stay at the level of the French submarine force, with war imminent that requirement was discarded.
The new U-Boat construction was primarily of 5 types. The most numerous was the Type VI, a 650-800 ton design meant for mass production and operating in the approaches to the Irish Sea. Next most numerous was the Type III, a 450 ton vessel meant for coastal defense and shallow water offensive operations ala the WWI UB and UC boats. Thirdly were the 11-1200 ton Type VIII large submarines, meant for long range operations. Related were the 1800 ton Type IX long range minelaying boats, which were functionally stretched type VIII boats. Lasty and rarest were the 4800 ton Type X cruiser submarines, with 4 128mm guns for commerce raiding and a floatplane scout…
…The British saw the German increase in U-Boat production and took it with appropriate alarm. In December 20 1000 ton escort destroyers were ordered along with an addition 6 sloops. Furthermore design work started on a class of austere ASW escorts for covering coastal traffic on the east coast of England, something faster and more capable than a trawler but cheaper than a sloop or destroyer…
…Realizing that they may have to conduct large scale shore bombardment again the turrets from the scrapped large light cruiser Courageous were used to build a pair of new monitors. It was further proposed to use turrets from the scrapped battlecruiser Tiger and Battleships Iron Duke and Benbow for additional monitors, however given limitations in building capacity it was decided to wait for the completion of the first pair to do so…
…There was a brief proposal in 1939 to scrap the battleships Queen Elizabeth and Warspite and reuse their guns for new battleships. The ships of the King Edward VIII class were delayed by both a shortage of armor and guns, the newer Conqueror class would be built at a slower rate, only two ships a year, meaning that the armor shortage would be alleviated, but the gun issue would remain. By scrapping the older battleships their guns and mountings could be reused in new battleships, and allow an extra pair of battleships to be squeezed in before 1945. These ships would be at least as good as the Admiral class battlecruisers and would be adequate against all but the newest enemy vessels. The Queen Elizabeth and Warspite were considered to be only good for convoy escort and shore bombardment, something the less worn out R class ships could do more cheaply, thus their loss was considered acceptable.
However this proposal was killed before it could be implemented. It would produce ships that while of adequate speed and protection would lack firepower compared to the already second class King Edward VIII’s and thus be third class vessels in the long term. Secondly it would in the short term deny the Royal Navy a pair of heavy convoy escorts, not something they wanted with war on the horizon. Finally the Royal Navy preferred to use the slip ways that would be building these ships to build an extra pair of aircraft carriers instead and ordered such by the end of the year…
…With budgetary limitations being removed in the wake of the Vicenza Conference and the near war scare the French navy took the chance to try and decisively get ahead of the Italians. While unable to accelerate their capital ship program given infrastructure complaints, they were able to restart construction of Heavy cruisers. A pair of 15,000 ton vessels were ordered with 9 8” guns, 14 100mm AA guns and excellent armor. They would use the machinery plant from the 18,000 ton Montgolfier class carrier, the first unit of which was laid down the year prior, but would make 33.5 knots rather than the 33 of the carrier. Another trio of 9,000 ton light cruisers was further authorized to give the French a superiority over the Italians there as well
Supporting these were a new tranche of heavy destroyers, 3500 ton monsters with 8 138mm and 4 100mm guns and a 39 knot speed. These were as well armed as the newest Italain cruisers, if not as fast or well protected. A further set of 2,000 ton Avisos was ordered for convoy protection as well. The size of the Heavy cruisers and destroyers was a major deviation from the treaty system, but it was justified by the existence of the German Panzerschiffe and the large number of 4000 ton Italian cruisers being laid down…
…The Italain navy saw that war was imminent and began a crash program to build large torpedo boats for sea denial and a class of corvettes to escort convoys to Libya. The former were 1000 ton vessels, while the latter were 750 ton vessels, both featuring many common components for ease of production. The designs were quickly licensed to the Spanish, who were looking to restart naval construction to replace their civil war losses…
…As their first pair of Littorio class battleships was completed the Italians looked at would follow the second pair. A proposal for 16” guns had been considered, but it had been decided that while an improvement over their 15” guns, it would not be a significant enough one to justify developing a new gun in the absence of the Treaty system. It was then proposed that a 17” gun be developed, as that would be a significant enough improvement. It was also a small enough improvement over a 16” gun, that the British had and French were developing, that they would not feel compelled to counter with a larger gun of their own.
Development of that gun would take time, and therefore the Italians decided that for their 7th and 8th post WWI battleship they would simply stretch the Littorio class to add a fourth 15” turret. The new design would be 50,000 tons, reach 31 knots, have a slightly improved armor scheme and replace the mixed 152mm and 100mm battery with 16 135mm DP guns. These would be followed by a 17” armed class of battleships, projected to be 52,000 tons, later in the decade…
…In 1939 the United States restarted orders for Heavy Cruisers. The 15,000 ton Columbus class vessels broke the old Treaty limits, but were justified on the basis of the Japanese presumably lying on the size of their new heavy cruisers. Like most new vessels of the post treaty era the increase in tonnage came mainly from adding back stability, seaworthiness and growth room, though AA armament was increased heavily as well.
The Columbus class was intended as a stopgap for a future design. The failure of the Treaty System caused the US to reevaluate what it wanted in a future heavy cruiser. Armament in particular was reconsidered, with the Treaty having artificially limited it. Proposals were made for designs with 12 8” guns, or for various amounts of 10” or even 12” guns for a treaty unlimited cruiser. Analysis soon showed that regarding armament 12 8” guns were inferior to 9 10” guns which were themselves inferior to 6 12” guns. This suggested that a future heavy cruiser should be armed with 12” guns and the development of such a gun was authorized. Until that could be completed the 8” gun would remain the standard heavy cruiser weapon…
…In 1939 the United States restarted large scale submarine construction. There had been a serious argument on what shape that construction should be. Most experienced submarine officers wanted a 1600-1800 ton design, smaller than the large submarine of the 20’s, but still capable of long range operations in the Pacific theatre. The General Board however wanted to build 800 ton coastal submarines to replace the R and S class submarines leftover from WWI, arguing the smaller austere vessels would be cheaper, easier to build more maneuverable and better suited for shallow water operations. In the end the latter argument won out, mostly by pointing out that everybody else was building such submarines, though a limited number of larger boats would be built as well…
…In 1939 testing of the domestic 1.1” autocannon revealed that it was barely adequate as an AA weapon. It could not be used for terminal defense like the .30 and .50 caliber machine guns it replaced in American service, and lacked the range to truly cover the gap between the 5” guns and machine guns. It was furthermore proving highly unreliable.
Competition was thus started for replacements to the weapon, with both a long range heavy autocannon and a short range light autocannon being needed. For the former the USN tested 40mm Bofors, British 2 pounder, Breda 37mm and the Army’s 1.5” gun. For the latter the Swiss Solothurn ST-5, Swiss Oerlikon, Danish Madsen, Italian Breda and a domestic Colt design derivative of the M-2, all 20mm weapons…
…In 1939 three of the most important arms tests of the interwar period occurred. In Japan many old freighters and barges were targeted in a series of tests off Hokkaido to demonstrate the new oxygen fueled torpedoes and better refine their tactics. Against stationary targets it was found that while accuracy at 11km and 22km was expected, that at 33km and 41km was far less than expected. This resulted in a doctrinal shift to closer firing at higher speed, and a slight modification to the gyros to avoid nose wander at long range.
In the United States funding was finally found for a series of live fire tests of the magnetic exploder used in the teen series of torpedo. These tests, off Central California and North Carolina, showed that the magnetic exploder functioned as designed, at least in those locations. Most testing however was done with the destroyer launched version, only a single shot from a submarine was conducted, as well as only a handful of drops from aircraft, all done particularly low and slow.
Finally in Germany there was a demonstration of their newest submarine torpedo on old freighter by a submerged U-Boat in front of Hitler himself in the Jade Bight. This proved particularly significant when all torpedoes failed to detonate on time, if at all. With such a public failure the Kriegsmarine was forced to rapidly modify its standard torpedo to fix the now revealed flaws…
…In 1939 the Japanese ordered their fourth pair of fleet carriers. Functionally armored deck versions of the previous Soryu class, the new Unryu class vessels would be 30,000 ton ships and the first of eight planned armored fleet carriers, to supplement the six unarmored carriers they had built or building and the eight shadow carriers they could convert from subsidized liners or submarine tenders. A variant of the design, smaller, simpler, unarmored and more austere, was prepared at the same time as an emergency fleet carrier, that could be rapidly built to supplement the superior designs…
…To match the Japanese buildup the United States ordered three additional carriers in 1939. The first was a repeat of the preceding Intrepid class of 25,100 ton carriers. The latter pair were a new 30,000 ton design, the Bonhomme Richard class. It had been proposed to use the extra 4900 tons to armor the flight deck, but the General Board preferred to expand aircraft capacity instead. Additional armor was fitted, but at the hangar deck level so that it could trip bomb fuses and set them off before they could pierce the armor deck protecting the machinery spaces and magazines. The Bonhomme Richard class would be the first fleet carriers to feature deck edge aircraft elevators. The feature had been tested on the converted collier USS Wright after her rebuild following a 1932 collision and found to be extremely useful. A minimum of two additional members of the class were planned to be ordered in 1941…
-Excerpt from Naval History Between the Wars, Harper & Brothers, New York, 2007
I didn't mean to write this much, it just happened. Anyways there may not be an update for this TL next Sunday. I don't have a day off until then so that may require bumping Tomorrows Pen to Sunday, leaving this update cancelled