WI:Krigesmarine type xxI

Honestly I don't think the Walther system could have enough of the bugs worked out of it to make it operational. Not to mention supplying the hydrogen peroxide, which was also needed for the Me-163 "Komet" and other rocket projects...
And it never was made practical. Walter and his research was taken to the UK after the war where the work was picked up where it left off, resulting in experimental hydrogen peroxide torpedoes and 2 boats (similar to the Type XVIII) of the Explorer class. Despite peacetime schedules and resources to solve problems better, the hydrogen peroxide torpedoes were abandoned after an explosion on a submarine, and the Explorers were abandoned after numerous reliability and teething issues occurred during their short service life(though never any real accidents) that could not be solved.

The Soviets independently developed hydrogen peroxide torpedoes post-war, and used them up until an accident sank the submarine Kursk in 2000, following which Russia phased out such torpedoes (they apparently never were considered very safe). The US developed hydrogen peroxide torpedoes as well during WWII (I can't remember the name of the engineer that came up with the idea), and used them in the Cold War, but like the others they were very dangerous to use (though they were lucky to never suffer an accident like everyone else). In the end hydrogen peroxide was (and is) even more dangerous than compressed oxygen, though it tripled the range of otherwise air-fueled torpedoes rather than merely doubled them like liquid oxygen did, so countries developed and used them before realizing they were too dangerous.
 
1. Just one thing to note. There was no room in the Type VII for more battery cells. In the Type IX, the Germans would have to sacrifice an engine. Since German tactics dictated surface torpedo boat like attack in a swarm or a pack and then dive to escape, that would not exactly be "smart" to rob an U-boat of its surface tactical speed. There is something called aggregate tactical speed of U-boat, torpedo and target. As an average in the battle of the Atlantic, this was about 5-6 m/s or 10-12 knots. Angle solutions for the typical German torpedo yielded aspect differences of no more than 140 degrees and run times of no more than 200 seconds off set run time on a rather average family of weapons rated at no more than 15-20 m/s (30-40 knots) and with run times at 800 seconds at 15 m/s or 400 seconds at 20 m/s. Note that the slow setting was for aggregate merchant vessel/U-boat tactical speed at (6 m/s) 12 knots, and the expected aggregate escort/U-boat tactical speed at about 6-7 m/s (16-18 knots).

2. There is a flaw in the thinking that suggests one needs a faster U-boat with a snort. The snort is useful as a battery recharge feature in an LRMP dense environment, One might like a quiet muffled and rafted Stirling cycle engine as the recharge engine though instead of a diesel: that is a quieter U-boat. In addition one might like to have a torpedo with a seeker in it that uses target noise or wake to home in on aforesaid target. The Germans develop pattern runners and they (1933 onward) try to develop an acoustic [self guided weapon] torpedo (one of the reasons for the G7e), but...

3. They are not very successful because they scatter their efforts, and do not understand what they try to accomplish. They are not very good systems analysis engineers. As has been known since the first WW I about guided weapons. (UK and France op-research in the 1920s.) If you want to improve chances in PH (hit) or PK (kill) and do that function most economically, then the solution is not the launcher, it is the projectile or missile. This is kind of obvious. No-one, except the Germans, despite knowing the solution, even tries for an acoustic or wake homing torpedo. The reasoning was simple at the time. The torpedoes possible (or so it was thought) were too noisy to make hydrophones work and with the vacuum tube technology available, it was not likely to work as the electronics would fail.

4. The Germans, British and Americans did get excited about maybe using magnetic influence to set off torpedoes. Mining effect. Close enough is good enough. Break keels, yoah! This was based off WW I German magnetic influence mines. Should have worked, but the short version is that Earth is a lumpy irregular magnet, and all three navies leaped to the wrong solution about how to use that magnet to set off their fusing mechanisms. Later in 1945, too late to do any of them any good, they all figure out self generated magnetic influence features and a rheostat is the way to make a magnetic influence feature work, but if you want to read about it in detail, (...Those Marvelous Tin Fish: The Great Torpedo Scandal Avoided)…

5. Meanwhile, there is the acoustic torpedo and the wake homer. The Germans have been working on the acoustic torpedo for quite a while. They finally get it to work around 1944-45 and start turning British escorts into "banana boats" with T-4 G7es that prang British escorts in the props and artificially hog the British ships by raising sterns. There is some question whether these are contact fuse hits or if the German magnetic influence feature sets off the fish early and the bubble lifts the frigate's stern. My guess is that the influence feature is at work because a lot of these banana boats survive. Not too smart. Wake homer (active sonar pings off the bubbles formed in a ship's wake flow and the fish follows the echoes) is a bust for the Germans. Note that all the fancy wonder weapon torpedoes are finicky, the electronics involved is fragile and the weapons are expensive? The seeking guided torpedoes are "rare" with a MFR of about 50% for the Germans.

6. Enter the United States. Worst torpedoes in the world. Circle back on you, run wild nose wander right, run deep, impact hammer fuses do not work, magnetic influence circuits go off early. Lots of clangers, target run unders or miss rights and prematures. Wrong tactics too, but the point is that the torpedoes MISS even when angle solutions and depths are correct. Enter HUSL. (I love puns.) Harvard Underwater Sound Laboratory. They are the sound version of the MIT Rad Lab. These guys include systems analysts. Despite US Navy and Congressional politics which impede solutions on the current weapons in use, these boys and girls figure out how to make an acoustic torpedo work in mere months. Thanks to the BRITISH who capturfed it and the Germans who supplied the weapon by accident, a complete U-boat with working electric torpedoes is also provided. OOPS. The Mark XVIII copied from the G7e is cheap and plentiful, and with a working warhead and able to gyro steer into a ship is good enough to kill freighters. The CUTIE, the submarine version of FIDO, (1944) starts killing Japanese escorts (as in SINKING them) about the same time the Germans turn British frigates into banana boats. 24 months for that one. CUTIE is not plentiful, but it is not all that rare either. The Mark XVIII with an acoustic seeker a true heavyweight guided weapon is 1945.

7. The upshot, primarily, is that the Americans develop FIDO (independent of German or British influence) in about 12 months, and the Allies start to kill U-boats with it around 18 August 1943 or 6 months later. It would not have mattered if the Type XXI had come into service. As I noted earlier, the Germans screwed up the Type XXI's screws. The FIDO is still just fast enough to catch it on battery in a hammer and anvil attack profile. And its faster cousin, the Mark 32, (postwar deployed) is on its way (1946?).

The Type XXI without an abundant source of guided weapons and still stuck with wrong tactics is not going to be the convoy killer the Germans hope it is. That is the whole point. The Americans were confronted with the same exact problems the Germans had. The Japanese merchant fleet had to be killed and the American subs were not getting it done. Design a new kind of sub as the Japanese ASW improved? (Oh yes; it improved.). No. The Americans had 20 different torpedo programs going. Not submarines... torpedoes.

Post-war these were rationalized down to fewer different types, including the finally debugged Mark XIV (freighter killer with a now working magnetic fuse), FIDO (sub-killer), the Mark XVIII and her anti-ship cousin the Mark 26 (CUTIE), and the Mark 28. But the US still worked on that wake homer, and more cousins to FIDO.

When the US did make her radical break with submarine design, (rather sedately in 1955) it was to obtain an atomic powered submarine for tactical offensive speed and true submerged operations. GUPPY and the Tenches were just stopgaps and were always so seen. The urgent effort was still in the torpedoes.

The Germans just never saw it. Maybe it was because their torpedoes were just good enough at the start that they did not see the urgent need in the right place?

seems like there would have been enough reason to revamp their near constant messaging by then? @McPherson suggested messaging buoys (IIRC, cannot find exact post

It is in the that storyline I manage, where I sank the USS Mudskipper after she kills Shokaku (#701?). In the mid 1930s, the USN developed an automated weather buoy which was dumped over the side of a destroyer or cruiser to radio back to a shore station or a weather ship, local sea conditions. From this contraption, complete with something called a wire loop repeater/recorder, they developed it into a sonobuoy that could be air dropped from a Sunderland or a Liberator and which could radio its findings to a destroyer or an airplane. That was about 1944 in OTL. The same technology was designed into a float line buoy that could mark the position of a downed submarine (SQUALUS disaster 1935.). The free float messenger buoy is just an extension of the available technology. Nothing fancy. The Germans or the British could have done the same. Why they did not (or why the US OTL did not) is curious. I suspect it is because they would have to give up a torpedo space in the racks to stow one and use it. I ITTL did it because it seems kind of necessary to mark the passing of a submarine. The ARA San Juan could have used one.
 
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[snip] The Soviets independently developed hydrogen peroxide torpedoes post-war, and used them up until an accident sank the submarine Kursk in 2000, following which Russia phased out such torpedoes (they apparently never were considered very safe).

The small QUEBEC-class Coastal Submarine used a similar system that caused continuous problems, the class was eventually abandoned as they were just too unsafe...
 
The small QUEBEC-class Coastal Submarine used a similar system that caused continuous problems, the class was eventually abandoned as they were just too unsafe...

Post war decision cycles are always difficult to compare to war time decisions. In most cases KM vessel is exposed to far more threat than some safety issues. If it allowed them to survive where they could not before, then that was an improvement!
 
And it never was made practical. Walter and his research was taken to the UK after the war where the work was picked up where it left off, resulting in experimental hydrogen peroxide torpedoes and 2 boats (similar to the Type XVIII) of the Explorer class. Despite peacetime schedules and resources to solve problems better, the hydrogen peroxide torpedoes were abandoned after an explosion on a submarine, and the Explorers were abandoned after numerous reliability and teething issues occurred during their short service life(though never any real accidents) that could not be solved.

The Soviets independently developed hydrogen peroxide torpedoes post-war, and used them up until an accident sank the submarine Kursk in 2000, following which Russia phased out such torpedoes (they apparently never were considered very safe). The US developed hydrogen peroxide torpedoes as well during WWII (I can't remember the name of the engineer that came up with the idea), and used them in the Cold War, but like the others they were very dangerous to use (though they were lucky to never suffer an accident like everyone else). In the end hydrogen peroxide was (and is) even more dangerous than compressed oxygen, though it tripled the range of otherwise air-fueled torpedoes rather than merely doubled them like liquid oxygen did, so countries developed and used them before realizing they were too dangerous.

Not sure that one can say NAVOL is more dangerous than oxygen in a torpedo. The Japanese IJN were far more careful than the Red Navy. It is true that NAVOL is more corrosive than doped pressurized oxygen, but then that is why torpedoes are supposed to be safety inspected. Does one think the Mark XVIII or the G7e were safe? Those were acid disasters waiting to explode, too.

The US engineer who developed the prototype NAVOL torpedo (~1935) was CDR (later RADM) Ralph Christie.

Post war decision cycles are always difficult to compare to war time decisions. In most cases KM vessel is exposed to far more threat than some safety issues. If it allowed them to survive where they could not before, then that was an improvement!

Yet; they decided to NOT use the Walther closed cycle engines. And it was for the reason the British belatedly discovered; maintenance nightmares and non-deployability issues. You cannot use a sub that spends 80% of its time under repair or maintenance at pier-side. Plus, where is one supposed to manufacture and store all that hydrogen peroxide fuel?
 
Not sure that one can say NAVOL is more dangerous than oxygen in a torpedo. The Japanese IJN were far more careful than the Red Navy. It is true that NAVOL is more corrosive than doped pressurized oxygen, but then that is why torpedoes are supposed to be safety inspected. Does one think the Mark XVIII or the G7e were safe? Those were acid disasters waiting to explode, too.
Compressed oxygen will only explode if it is hit by open sparks, flame, or suffers impact (i.e. it gets shot at). NAVOL will explode if a moderate-sized leak occurs and dissolve nearly anything, in addition to the open sparks/flame/impact that sets off compressed oxygen. Even today the safety hazards sheet/required warning labels for highly concentrated hydrogen peroxide are longer and more strict than those for compressed oxygen because of the instability of hydrogen peroxide. Which would explain comments like this on the Navweaps forum:
I'm trying to find the reference but somebody in the USN said they would rather use wound up rubber bands than hydrogen peroxide to propel torpedoes. I'll keep looking.
 
Compressed oxygen will only explode if it is hit by open sparks, flame, or suffers impact (i.e. it gets shot at). NAVOL will explode if a moderate-sized leak occurs and dissolve nearly anything, in addition to the open sparks/flame/impact that sets off compressed oxygen. Even today the safety hazards sheet/required warning labels for highly concentrated hydrogen peroxide are longer and more strict than those for compressed oxygen because of the instability of hydrogen peroxide. Which would explain comments like this on the Navweaps forum:

That is not how pure oxygen works or why it is dangerous in a torpedo. If you get the even the slightest amount of oil or dirt in a pressurized gas line that feeds oxygen under pressure to a combustion pot in a torpedo it sets off a fire that travels along the gas path which the oxygen sustains from pot to tank and bursts the torpedo. It is not that PURE oxygen is explosive or that it is corrosive (though it will eat through non chemically stabilized oxidizable (note the word?) alloys faster than even hydrogen peroxide). It supports combustion radically even in IRON in the process of drop from high pressure to low pressure gas in a pressurized system unless the feed is controlled. It is so incredibly dangerous that the Japanese after several accidents discovered that the only safe way to use oxygen in a torpedo was to employ a small flask of normal pressurized air to start the wet heater engine and when it exhausted then open the feed to the oxygen bottle and let the oxygen feed into a controlled burn, and then dope the oxygen with a small amount of inert gas to allow a gas feed without the rapid almost instantaneous oxidation of the feed lines. Not only that, but the Japanese in the manufacture of the torpedo insisted on virtual NASA clean room conditions to assemble the power unit on their torpedo with special emphasis on making sure that there was no kinking or sharp bends in the feed lines from tanks to pot. No weak spots for oxidation burn through, no oil or dirt to support combustion anywhere except in the combustion pot. Otherwise... BOOM. 100% guaranteed.
 
Another spoiler to the wonder-U-boat is the allied reaction to intelligence regarding the building of this new threat. Once the allies accept that the convoys are at serious risk the tasking of the bomber force will change and every effort will be made to impede the U boat production cycle.
 
Was under the impression that the US used Mark-14 from WWII and then Mark-37 electric until changing over to the Mark-48 around 1972. Then the Mark-48 ADCAP came out in mid to late 80s due to the Alfa. Mark-48 uses Otto Fuel II.
 
Was under the impression that the US used Mark-14 from WWII and then Mark-37 electric until changing over to the Mark-48 around 1972. Then the Mark-48 ADCAP came out in mid to late 80s due to the Alfa. Mark-48 uses Otto Fuel II.

Here.

US torpedoes from subs in WW II; were CUTIE, Mark XIV, Mark XVIII, Mark 26. Mark 16 was supposed to be in service, but arrived too late.
 
Here.

US torpedoes from subs in WW II; were CUTIE, Mark XIV, Mark XVIII, Mark 26. Mark 16 was supposed to be in service, but arrived too late.

My mistake. Was responding to this;
“The US developed hydrogen peroxide torpedoes as well during WWII (I can't remember the name of the engineer that came up with the idea), and used them in the Cold War, but like the others they were very dangerous to use (though they were lucky to never suffer an accident like everyone else). In the end hydrogen peroxide was (and is) even more dangerous than compressed oxygen, though it tripled the range of otherwise air-fueled torpedoes rather than merely doubled them like liquid oxygen did, so countries developed and used them before realizing they were too dangerous.”

I listed torpedoes that the US used during the post WWII period/Cold War. Didn’t know the US had used a hydrogen peroxide one. Never heard about or saw one on any of the boats I was on.
 
My mistake. Was responding to this;
“The US developed hydrogen peroxide torpedoes as well during WWII (I can't remember the name of the engineer that came up with the idea), and used them in the Cold War, but like the others they were very dangerous to use (though they were lucky to never suffer an accident like everyone else). In the end hydrogen peroxide was (and is) even more dangerous than compressed oxygen, though it tripled the range of otherwise air-fueled torpedoes rather than merely doubled them like liquid oxygen did, so countries developed and used them before realizing they were too dangerous.”

I listed torpedoes that the US used during the post WWII period/Cold War. Didn’t know the US had used a hydrogen peroxide one. Never heard about or saw one on any of the boats I was on.

The USN was never happy with NAVOL. Only the Oxygen Torpedo (酸素魚雷) forced the USN to reconsider Christie's crazy prototype. In the end, the debugged Mark XIV was good enough. The horror show Mark XVIII electric happens because the Mark XIV was not amenable to mass production and the US did not have enough watchmakers to hand make those fish in the numbers needed. It is one of the few poor industrial decisions American war-planners make. The Mark 26 is the simplified Mark XIV, with the fast speed setting. The CUTIE is the destroyer killer version of FIDO. OTTO fuel is what the USN really wanted for torpedo propellant. It is only mildly hazardous, but still needs some careful handling.
 
Another spoiler to the wonder-U-boat is the allied reaction to intelligence regarding the building of this new threat. Once the allies accept that the convoys are at serious risk the tasking of the bomber force will change and every effort will be made to impede the U boat production cycle.


This was already being done with very limited success.
 
The Type XXI without an abundant source of guided weapons and still stuck with wrong tactics is not going to be the convoy killer the Germans hope it is. That is the whole point. The Americans were confronted with the same exact problems the Germans had. The Japanese merchant fleet had to be killed and the American subs were not getting it done. Design a new kind of sub as the Japanese ASW improved? (Oh yes; it improved.). No. The Americans had 20 different torpedo programs going. Not submarines... torpedoes.

When the US did make her radical break with submarine design, (rather sedately in 1955) it was to obtain an atomic powered submarine for tactical offensive speed and true submerged operations. GUPPY and the Tenches were just stopgaps and were always so seen. The urgent effort was still in the torpedoes.

The Germans just never saw it. Maybe it was because their torpedoes were just good enough at the start that they did not see the urgent need in the right place?

thanks for highlighting this aspect! the torpedo research might have to be driven by Luftwaffe? although KM was charged with coastal defense to some extent and might have wanted to develop long range torpedo batteries.

my understanding the u-boat commanders, if not entire KM leadership shied away from minelaying duties in favor of using deck guns and torpedoes, but they had fairly developed magnetic mines?

was there something else to be developed? paravane or towed mines? or some changes to deck guns?
 
thanks for highlighting this aspect! the torpedo research might have to be driven by Luftwaffe? although KM was charged with coastal defense to some extent and might have wanted to develop long range torpedo batteries.

Oddly enough FIDO, the American anti-submarine warfare air dropped torpedo, started out as an Army air forces project that was snapped up by the Navy as soon as the Harvard Underwater Sound Laboratory showed how it could be done.

my understanding the u-boat commanders, if not entire KM leadership shied away from minelaying duties in favor of using deck guns and torpedoes, but they had fairly developed magnetic mines?

That is an interesting comment. Charleston, South Carolina, had its harbor shut down for almost a half year by one U-boat using submarine laid magnetic mines. It took about forty vessels of various kinds and several teams of scarce USN dive/salvage experts to clear the mines out.

This leads to the question of why not use this as standard practice if it is so effective?

Well, there is a long answer and a short answer. The short answer is that it depends on harbor entrance geography, approach depths, currents and tides, how good the ASW local patrols are, the psychology of the opposing navies and whether or not the minelaying submarine has a crew with nerves of steel. U-455 had an easy harbor to plug. A U-boat using the existing German mines would be a guaranteed Himmelfahrtskommando off the Thames estuary by contrast. The preferred method to lay mines is via aircraft. That is another whole set of problems. The modern submarine solution is something called a mobile mine. The submarine launches it at the harbor entrance like a torpedo, it moves out and at some point depending on its guidance it deposits itself Murphy knows where. NASTY and effective.

was there something else to be developed? paravane or towed mines? or some changes to deck guns?

I play around with some notions, but the WW II RTL boys were fairly sharp. They knew what could and could not be done. My guess is that if you refer to those ideas as ASW weapons, those were tried. Noisemaker paravanes and tow decoys might have / were developed for ships or subs by several navies. Banzai Bob^1, assigned noisemaker station and duty, will be very unhappy about it for obvious reasons. Deck guns have an upper limit in size due to mass and recoil forces. Subs roll, boy do they roll, in a seaway.

Banzai Bob is my name for the suicide bodyguard ship assigned her suicide mission and station to protect the rest of the fleet or in many cases one very valuable ship.

Examples:
1. Radar picket destroyer. Her station is to stand guard as the outside picket / sentry on the threat axis. Her job is to radiate and warn the other ships (silent) of an incoming air raid and to draw the attackers on to herself. Guaranteed Presidential Unit Citation if she does her job right.
2. Aircraft carrier close bodyguard. The destroyer is to listen for enemy torpedoes and put herself between the torpedoes and her aircraft carrier charge. I have used this in the Timeline to which I contribute. That is how the USS Hammann gets it. Guaranteed Presidential Unit Citation. It is a tough gig being a US destroyer and that is for real.
 
Banzai Bob is my name for the suicide bodyguard ship assigned her suicide mission and station to protect the rest of the fleet or in many cases one very valuable ship.
.

I have always claimed that you should not join the military if you cannot take a joke.....
 
was there something else to be developed? paravane or towed mines? or some changes to deck guns?

The preferred method to lay mines is via aircraft. That is another whole set of problems. The modern submarine solution is something called a mobile mine. The submarine launches it at the harbor entrance like a torpedo, it moves out and at some point depending on its guidance it deposits itself Murphy knows where. NASTY and effective.

Noisemaker paravanes and tow decoys might have / were developed for ships or subs by several navies. Banzai Bob^1, assigned noisemaker station and duty, will be very unhappy about it for obvious reasons. Deck guns have an upper limit in size due to mass and recoil forces. Subs roll, boy do they roll, in a seaway.

thanks for the info!

mobile mines were what I had in mind, wasn't certain about the international law on where they could be launched? and the towed paravane or mine to defend against pursuing ship?
 
McPherson wrote:
Banzai Bob is my name for the suicide bodyguard ship assigned her suicide mission and station to protect the rest of the fleet or in many cases one very valuable ship.

Examples:
1. Radar picket destroyer. Her station is to stand guard as the outside picket / sentry on the threat axis. Her job is to radiate and warn the other ships (silent) of an incoming air raid and to draw the attackers on to herself. Guaranteed Presidential Unit Citation if she does her job right.
2. Aircraft carrier close bodyguard. The destroyer is to listen for enemy torpedoes and put herself between the torpedoes and her aircraft carrier charge. I have used this in the Timeline to which I contribute. That is how the USS Hammann gets it. Guaranteed Presidential Unit Citation. It is a tough gig being a US destroyer and that is for real.

Really? In my AF career we simply called it by its official title drawn directly from out “Job Description” of duties:
“Other Duties as assigned by Competent Authority or Command”

Which is why I laugh so long and hard when a ‘grunt’ in a movie says “I didn’t sign up for this sh*t!” because YES in fact you DID sign up for this sh*t and you had better believe this is likely NOT the worst you signed up for either :)

Cryhavoc101 wrote:
I have always claimed that you should not join the military if you cannot take a joke.....

It’s a fair assessment actually. Also funny to note a few years ago an informal survey of military veterans found that when ranking “motivational” speeches from military movies one of the top 5 was Bill Murray from “Stripes” :)

Randy
 
Really? In my AF career we simply called it by its official title drawn directly from out “Job Description” of duties:
“Other Duties as assigned by Competent Authority or Command”

You could shorten it to ODAA loop, you know?

mobile mines were what I had in mind, wasn't certain about the international law on where they could be launched? and the towed paravane or mine to defend against pursuing ship?

A mobile mine is in a grey area in international law. Certainly a drift mine is illegal as it is a terrorist weapon. What do you mean by defend against a pursuing ship? Usually paravanes are cable cutters for chain moored mines to pop them to the surface where they can be destroyed. If you mean a towed decoy, that is a seducer to draw a seeking weapon off a likely high value target. The problem is that once the decoy attracts the weapon, the weapon usually drives through the decoy and heads for what tows it, hence the Presidential Unit Citation that follows the result.
 
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