What if the Type 21 U-Boats became operational in 1940?

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JAG13
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Re: What if the Type 21 U-Boats became operational in 1940?

Post by JAG13 » 18 Dec 2019 18:27

T. A. Gardner wrote:
18 Dec 2019 17:47
JAG13 wrote:
18 Dec 2019 15:24

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.
Why? Because Courageous got sunk and Ark Royal almost did as well, the RN withdrew them from ASW work on top of having very few aircraft and even fewer radar sets.
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.

Image

The problem was their tactics were sloppy and everything was in short supply. They were simply fighting a war way in over their heads.
And? I didnt blame equipment, I simply said they were incompetent in ASW so the USN got away with using radar on subs which is outrageous.
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.
Do you have an actual concrete technological development to mention or just hand waving?
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.
Please quote the USN study that thereafter contradicted Adm. Nimitz conclusion.
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

Image

Now, that was a huge surprise to the Allies.
Not really an answer.
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.
You dont get a change without change... Germany led the world in radar technology, when Dönitz made his 1938 wargames against night convoys a junior Lt. noted that all was needed was for the Nüremberg to turn on its radar and the Uboats would have all been spotted, and KM ships were reluctant to use their radar for fear of broadcasting their position, even early war. The need for ESM should have been obvious, hence its inclusion in the "foresight" list.

The KM monopolized early radar development due to the LW feud and neglected anything they couldnt use, they even tried to prevent GEMA from selling anything to the LW... and since they had almost no aircarft they of course saw little point on putting much emphasis on airborne radar, just to add an example.
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.
Again, foresight, both air and naval industry would benefit from being incipient or almost dead had the Germans had the foresight to implement mass production technologies that were widely available.

Modular construction and dispersion was devised by Junkers pre-war in its takt-time process, it was not new even for the Germans, they simply failed to widely implement something they already had and could have enforced by threatening to withhold public loans.
Last edited by JAG13 on 18 Dec 2019 18:37, edited 1 time in total.

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Re: What if the Type 21 U-Boats became operational in 1940?

Post by glenn239 » 18 Dec 2019 18:37

TheMarcksPlan wrote:
17 Dec 2019 04:19

Upthread I've said that I doubt T21 would be more effective at sinking ships than historical Uboats were pre-May43. So we agree there.
But it's not the per ship stats that matter, it's the total tonnage. OTL Uboat production peaked just as the Uboats were becoming useless.
Type XXI's in numbers and with support bases nearby might have posed a considerable threat to Allied anchorages during amphibious operations.

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Re: What if the Type 21 U-Boats became operational in 1940?

Post by TheMarcksPlan » 23 Dec 2019 01:32

glenn239 wrote:
18 Dec 2019 18:37
TheMarcksPlan wrote:
17 Dec 2019 04:19

Upthread I've said that I doubt T21 would be more effective at sinking ships than historical Uboats were pre-May43. So we agree there.
But it's not the per ship stats that matter, it's the total tonnage. OTL Uboat production peaked just as the Uboats were becoming useless.
Type XXI's in numbers and with support bases nearby might have posed a considerable threat to Allied anchorages during amphibious operations.
Type 23 even more so. They're cheaper, harder to spot on sonar, and you're not risking as much by deploying them in tight waters. They could have wreaked havoc on Husky/Salerno in 43.

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Re: What if the Type 21 U-Boats became operational in 1940?

Post by glenn239 » 23 Dec 2019 18:50

Normandy as well, with the bomb proof U-boat pens nearby.

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Re: What if the Type 21 U-Boats became operational in 1940?

Post by Takao » 23 Dec 2019 20:20

glenn239 wrote:
23 Dec 2019 18:50
Normandy as well, with the bomb proof U-boat pens nearby.
Let me know when the German invent mine proof seas, bays, and water ways.

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Re: What if the Type 21 U-Boats became operational in 1940?

Post by Takao » 23 Dec 2019 20:25

TheMarcksPlan wrote:
23 Dec 2019 01:32
glenn239 wrote:
18 Dec 2019 18:37
TheMarcksPlan wrote:
17 Dec 2019 04:19

Upthread I've said that I doubt T21 would be more effective at sinking ships than historical Uboats were pre-May43. So we agree there.
But it's not the per ship stats that matter, it's the total tonnage. OTL Uboat production peaked just as the Uboats were becoming useless.
Type XXI's in numbers and with support bases nearby might have posed a considerable threat to Allied anchorages during amphibious operations.
Type 23 even more so. They're cheaper, harder to spot on sonar, and you're not risking as much by deploying them in tight waters. They could have wreaked havoc on Husky/Salerno in 43.
Because the U-Boats performed so well during Torch...The electroboats will never be able to catch the fast troop convoys(14 knots).

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Re: What if the Type 21 U-Boats became operational in 1940?

Post by TheMarcksPlan » 23 Dec 2019 20:30

Takao wrote:
23 Dec 2019 20:20
glenn239 wrote:
23 Dec 2019 18:50
Normandy as well, with the bomb proof U-boat pens nearby.
Let me know when the German invent mine proof seas, bays, and water ways.
Let me know when you and your time machine change the fact that at least six T23's operated inshore around the British Isles, sinking 14k tons, without loss of a single vessel.

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Re: What if the Type 21 U-Boats became operational in 1940?

Post by Orwell1984 » 23 Dec 2019 20:50

TheMarcksPlan wrote:
23 Dec 2019 20:30
Takao wrote:
23 Dec 2019 20:20
glenn239 wrote:
23 Dec 2019 18:50
Normandy as well, with the bomb proof U-boat pens nearby.
Let me know when the German invent mine proof seas, bays, and water ways.
Let me know when you and your time machine change the fact that at least six T23's operated inshore around the British Isles, sinking 14k tons, without loss of a single vessel.
No they didn't.
Here's the wikipedia entry:
https://en.wikipedia.org/wiki/Type_XXIII_submarine
but they sank or damaged five ships for a total of 14,601 gross register tons (GRT).
Note use of the phrase "sank or damaged", not sunk.

Let's see what U-boat.net says, a site that has proven to be quite reliable in the past:
https://uboat.net/types/xxiii.htm
None of the 6 operational XXIII's (U-2321, U-2322, U-2324, U-2326, U-2329 and U-2336) was sunk by the allies during Jan - May 1945. 3 of these boats sank 4 ships for a total of 7,392 tons.
And as to losses:
U-2323 (mined on 26 July 1944), U-2331 (training accident on 10 Oct 1944), U-2338 (sunk by British aircraft east-northeast of Frederika on May 4, 1945, the only XXIII to be sunk by the enemy, 12 dead) U-2342 (mined on 26 Dec 1944), U-2344 (rammed by U-2336 on 18 Feb 1945), U-2351 (paid off in April 1945 after bomb damages) and U-2367 (rammed by U-boat on 5 May 1945).
3 own goals (doesn't say much about the state of crew training at the time)
2 by mines
2 by aircraft (one sunk, one damaged enough to be written off)

Another factor weighing against the XXIII
The XXIII was so crammed internally that she only carried two torpedoes and those had to be loaded externally in harbour, thus they lacked the offensive punch of their larger sister, the XXI Elektro boat.

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Re: What if the Type 21 U-Boats became operational in 1940?

Post by TheMarcksPlan » 23 Dec 2019 21:01

Orwell1984 wrote:
23 Dec 2019 20:50
TheMarcksPlan wrote:
23 Dec 2019 20:30
Takao wrote:
23 Dec 2019 20:20
glenn239 wrote:
23 Dec 2019 18:50
Normandy as well, with the bomb proof U-boat pens nearby.
Let me know when the German invent mine proof seas, bays, and water ways.
Let me know when you and your time machine change the fact that at least six T23's operated inshore around the British Isles, sinking 14k tons, without loss of a single vessel.
No they didn't.
Here's the wikipedia entry:
https://en.wikipedia.org/wiki/Type_XXIII_submarine
but they sank or damaged five ships for a total of 14,601 gross register tons (GRT).
Note use of the phrase "sank or damaged", not sunk.

Let's see what U-boat.net says, a site that has proven to be quite reliable in the past:
https://uboat.net/types/xxiii.htm
None of the 6 operational XXIII's (U-2321, U-2322, U-2324, U-2326, U-2329 and U-2336) was sunk by the allies during Jan - May 1945. 3 of these boats sank 4 ships for a total of 7,392 tons.
And as to losses:
U-2323 (mined on 26 July 1944), U-2331 (training accident on 10 Oct 1944), U-2338 (sunk by British aircraft east-northeast of Frederika on May 4, 1945, the only XXIII to be sunk by the enemy, 12 dead) U-2342 (mined on 26 Dec 1944), U-2344 (rammed by U-2336 on 18 Feb 1945), U-2351 (paid off in April 1945 after bomb damages) and U-2367 (rammed by U-boat on 5 May 1945).
3 own goals (doesn't say much about the crew training)
2 by mines
2 by aircraft (one sunk, one damaged enough to be written off)

Another factor weighing against the XXIII
The XXIII was so crammed internally that she only carried two torpedoes and those had to be loaded externally in harbour, thus they lacked the offensive punch of their larger sister, the XXI Elektro boat.
OK my last post was likely wrong about *0* losses but 2 losses among many boats operating/training for months doesn't augur well for mines being a magic bullet against T23. (Query whether the 2 losses to mines befell the 6 operational T23 or untrained, unlucky crews operating the far more numerous T23's that didnt become operational - for the purposes of this discussion I'll maintain my confession of error as well as the correctness of my original overall contention).

Re cramped conditions - what's the relevance? In analyzing potential losses inflicted by T23, do the Allies get some of their sunken ships back whenever a crewman elbows a comrade for lack of space?

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Re: What if the Type 21 U-Boats became operational in 1940?

Post by T. A. Gardner » 23 Dec 2019 21:22

One of the most serious problems with the Type XXIII was it had been designed with a very fast submerge rate. That is, it had a very small positive buoyancy to make it submerge quickly. The submerge time was just 20 seconds. When you couple that with the original low conning tower of the design, the problem becomes obvious. At least a couple were lost due to wave action where a wave washed over the sub and conning tower allowing some flooding to occur, which caused the boat to partially submerge, and well... you lose the boat.

According to Erwin Sieche in The German Type XXIII Submarine in Warship #19 (Conway 1981), U2331 sank this way in a training accident on 10/11/44 off Hela, and U2326 sank in a similar accident on 12/6/46 while being operated by the French Navy off Toulon. The Hai (S-170) of the W. German Navy sank in the same way on 9/14/66. In all three cases, the entire crew was lost.

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Re: What if the Type 21 U-Boats became operational in 1940?

Post by Orwell1984 » 23 Dec 2019 22:04

TheMarcksPlan wrote:
23 Dec 2019 21:01


OK my last post was likely wrong about *0* losses but 2 losses among many boats operating/training for months doesn't augur well for mines being a magic bullet against T23. (Query whether the 2 losses to mines befell the 6 operational T23 or untrained, unlucky crews operating the far more numerous T23's that didnt become operational - for the purposes of this discussion I'll maintain my confession of error as well as the correctness of my original overall contention).

Re cramped conditions - what's the relevance? In analyzing potential losses inflicted by T23, do the Allies get some of their sunken ships back whenever a crewman elbows a comrade for lack of space?
There's no likely about it. Your post was wrong. I notice you've failed to mention your incorrect claim for 14k tons of vessels sunk which is grossly over inflated as the actual tonnage sunk was closer to half that. (7,392 tons or 4 vessels in total).

Breaking it down further

6 operational type XXIIIs

Three boats sank 4 ships.

Three boats sank zero ships.


So for using basic reductive math as some are wont to do:
Only 50% of the operational boats sank a ship.
Of the ones that sank a ship, two had a 50% sinking rate from the torpedoes they carried
One, U-2336, sank two ships, a 100% hit rate for torpedoes. It also rammed and sank U-2344 so its service record can be considered checkered at least.

Over all break down:

7 lost u boats for 4 sunk ships
A loss ratio of 1.75 to 1 against the uboats.
Or tonnage wise 1 U-boat lost for every 1,056 tons sunk.

Of course just looking at the bare numbers without taking into account non-numerical data and using such base reductive reasoning is a fool's game.

Things that look great on the drawing board or on the balance sheet often do not work as well when subjected to real world experience.

As to the cramped conditions, the relevance is right there in the sentence quoted. Please re-read it.

Here's the key point:

Due to the cramped hull, each Type XXIII could only carry two torpedoes with no reload capacity without returning to port.

The type XXI could carry 23 torpedoes (ten times as much)
The type VIIC could carry approximately 14 torpedoes (7 times as much)

And both could reload at sea.

Even if we assume a 100% hit and sinking rate per sortie for each XXIII (which almost never happened), that's two ships at most for each XXIII per sortie. Then we add major issues in conducting a sustained campaign with the number of boats built, number of weapons carried, transit issues (having to run the gamut of Allied mine fields more often than other types of boats due to having to return to base to reload) and issues in crew training.

The XXIII's ROI is looking less and less promising.

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Re: What if the Type 21 U-Boats became operational in 1940?

Post by Takao » 24 Dec 2019 00:19

TheMarcksPlan wrote:
23 Dec 2019 20:30
Takao wrote:
23 Dec 2019 20:20
glenn239 wrote:
23 Dec 2019 18:50
Normandy as well, with the bomb proof U-boat pens nearby.
Let me know when the German invent mine proof seas, bays, and water ways.
Let me know when you and your time machine change the fact that at least six T23's operated inshore around the British Isles, sinking 14k tons, without loss of a single vessel.
The same time you let me know that the invasion fleet of Torch, Husky, Overlord, etc. Was composed of only 4 ships.

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Re: What if the Type 21 U-Boats became operational in 1940?

Post by TheMarcksPlan » 24 Dec 2019 00:47

Orwell1984 wrote:
23 Dec 2019 22:04
TheMarcksPlan wrote:
23 Dec 2019 21:01


OK my last post was likely wrong about *0* losses but 2 losses among many boats operating/training for months doesn't augur well for mines being a magic bullet against T23. (Query whether the 2 losses to mines befell the 6 operational T23 or untrained, unlucky crews operating the far more numerous T23's that didnt become operational - for the purposes of this discussion I'll maintain my confession of error as well as the correctness of my original overall contention).

Re cramped conditions - what's the relevance? In analyzing potential losses inflicted by T23, do the Allies get some of their sunken ships back whenever a crewman elbows a comrade for lack of space?
There's no likely about it. Your post was wrong.
Bro next time you try to flex based on a single short online source, at least read your source correctly:
None of the 6 operational XXIII's (U-2321, U-2322, U-2324, U-2326, U-2329 and U-2336) was sunk by the allies during Jan - May 1945. 3 of these boats sank 4 ships for a total of 7,392 tons.

The following 7 boats were lost to various causes;

U-2323 (mined on 26 July 1944), U-2331 (training accident on 10 Oct 1944), U-2338 (sunk by British aircraft east-northeast of Frederika on May 4, 1945, the only XXIII to be sunk by the enemy, 12 dead) U-2342 (mined on 26 Dec 1944), U-2344 (rammed by U-2336 on 18 Feb 1945), U-2351 (paid off in April 1945 after bomb damages) and U-2367 (rammed by U-boat on 5 May 1945
https://uboat.net/types/xxiii.htm

So my "query" point is exactly right: none of the losses were operational T23's. I retract my earlier confession of error.

I conceded error incorrectly because I trusted that you read your own citation (except on sunk vs. (Sunk+damaged)- there I was wrong). I am sure you will be as committed to truth as I am, considering your member name. I am sure you will reissue your math framed against the 61 T23's that were training in narrow Baltic waters, only ~10% of which were destroyed.

To do otherwise, to pretend you weren't wrong and deceptive in in your analysis would be like double-speak. Surely Orwell1984 wouldn't subject us to that.

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Re: What if the Type 21 U-Boats became operational in 1940?

Post by Takao » 24 Dec 2019 01:21

TheMarcksPlan wrote:
24 Dec 2019 00:47
Orwell1984 wrote:
23 Dec 2019 22:04
TheMarcksPlan wrote:
23 Dec 2019 21:01


OK my last post was likely wrong about *0* losses but 2 losses among many boats operating/training for months doesn't augur well for mines being a magic bullet against T23. (Query whether the 2 losses to mines befell the 6 operational T23 or untrained, unlucky crews operating the far more numerous T23's that didnt become operational - for the purposes of this discussion I'll maintain my confession of error as well as the correctness of my original overall contention).

Re cramped conditions - what's the relevance? In analyzing potential losses inflicted by T23, do the Allies get some of their sunken ships back whenever a crewman elbows a comrade for lack of space?
There's no likely about it. Your post was wrong.
Bro next time you try to flex based on a single short online source, at least read your source correctly:
None of the 6 operational XXIII's (U-2321, U-2322, U-2324, U-2326, U-2329 and U-2336) was sunk by the allies during Jan - May 1945. 3 of these boats sank 4 ships for a total of 7,392 tons.

The following 7 boats were lost to various causes;

U-2323 (mined on 26 July 1944), U-2331 (training accident on 10 Oct 1944), U-2338 (sunk by British aircraft east-northeast of Frederika on May 4, 1945, the only XXIII to be sunk by the enemy, 12 dead) U-2342 (mined on 26 Dec 1944), U-2344 (rammed by U-2336 on 18 Feb 1945), U-2351 (paid off in April 1945 after bomb damages) and U-2367 (rammed by U-boat on 5 May 1945
https://uboat.net/types/xxiii.htm

So my "query" point is exactly right: none of the losses were operational T23's. I retract my earlier confession of error.

I conceded error incorrectly because I trusted that you read your own citation (except on sunk vs. (Sunk+damaged)- there I was wrong). I am sure you will be as committed to truth as I am, considering your member name. I am sure you will reissue your math framed against the 61 T23's that were training in narrow Baltic waters, only ~10% of which were destroyed.

To do otherwise, to pretend you weren't wrong and deceptive in in your analysis would be like double-speak. Surely Orwell1984 wouldn't subject us to that.
Bro, it was your own poorly worded statement that started this...

Let's also not forget that the Type XXIIIs were also operating in far off Norway. Kinda hard to defend the shores of France from Norway. Also, keeps the safe and away from all the action.

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Re: What if the Type 21 U-Boats became operational in 1940?

Post by Takao » 24 Dec 2019 01:59

For Overlord,
The Allies scuttled over 50 merchant vessels of about 300,000 gross tons in constructing the artificial ports that were used so successfully during the invasion.
Says a lot about how successful these Type XXIIIs will need to be...If the Allies are intentionally sinking 50 merchant vessels. Right there is 75 Type XXIIIs worth of sunken ships.

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