JAG13 wrote: ↑18 Dec 2019, 16:24
If its 1940 forget about carrier ASW... specially radar equipped.
Why? Aircraft with ASV I or II sets were in use in 1940, that includes some Albacore on carriers. The USN had manufacturing of similar sets underway for their aircraft.
The USN had no ASW opposition, the IJN was utterly clueless in that regard, a point proven precisely by the fact that the USN could use radar with impunity, usually a no-no for submarines since it broadcasted its presence.
Not true. The Japanese tried to mount an effective ASW campaign and did equip many ships and aircraft with radar like this B5N.
The problem was their tactics were sloppy and everything was in short supply. They were simply fighting a war way in over their heads.
Which is why they were about to deploy the active Geier and even a wire-guided torpedo steered by the sonar operator.
For every measure, there's a counter-measure. The Germans were just as frustrated by Allied technological advances, and the Allies have the advantage of greater resources to come up with a counter-measure.
Lets see what Adm. Nimitz really thought of the type XXI and its effect, after extensive trials of course:
"These tests (...) have demonstrated that this particular submarine can with relative immunity attack a convoi or task group screened by the usual means and in deep water is virtually immune by any ship or aircraft or combination of both yet developed."
From a leter to Truman in June 1946.
That's at the time. Often the hindsight of history shows us a different picture. That's why we have these historical "what if's" for example. One of the most widely debunked is that Germany could have carried out Seelöwe successfully. At the time, Britain really believed they might manage it and took defense of England very seriously. Hindsight shows the British almost panic to get a defense in place was overblown.
So no, the Germans made a significant leap forward with the sub and the USN had a VERY hard time trying to detect the sub in tests, much less in actually setting up an attack.
Yes, the Type XXI did make a big advance in submarine technology, but not for high underwater speed. There were other fast underwater subs prior to it. The British R class in WW I. The Japanese I 201 and Ha 201 classes, as two examples. The GHG Balkon sonar
Now, that was a huge surprise to the Allies.
And that is the problem of this scenario, the Type XXI was a child of war, you simply cant get it without the 3 years of war development that molded it.
However you can wonder what aspects or elements of it you could have gotten with a bit more foresight, such as modular construction for mass production as the RN feared pre-war, working torpedoes, snorkel, ESM and that is it...which is quite a lot already.
The ESM you can't get without a need for it. The Germans were very slow to react to Allied developments in electronics and when they did it was often haphazard initially like the Naxos detector.
The Type XXI displaced twice as much and yet required 2/3 the man hours to build, apply such design considerations to an hypothetical Type VII designed for mass production and the KM can ramp up production in 1938 once the AGNA is scrapped, that alone would be a huge problem for the RN.
But without the impetus of war German companies are not going to look for such production methods. The meister system of skilled professionals and strong unions would have resisted this. Even the Nazis actively trying to undermine that system really never were able to. It was the wartime need to do production in the face of declining numbers of skilled craftsmen (often drafted for service a mistake the Japanese shared) and the use of semi- and unskilled labor that drove much of the process. Modular construction dispersed that making it less prone to being bombed out, a major reason the Germans adopted such measures.