WI:Krigesmarine type xxI

[Cryhavoc101]

McPherson wrote:


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:


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

I was being flown all over Salisbury plains once in a Blue Eagles Helicopter display team piloted Lynx - interesting experience - often looking at things like Stonehenge etc at some very odd angles - but I digress - one of the passengers asked if the altitude we were at is the same height paratroopers would jump at - the Pilot considered the question and then said yes.....but if they had done better at school they could have stayed with the aircraft.....

 

[RanulfC]

You could shorten it to ODAA loop, you know?

Could but we did love to "quote" that "Competent or Command Authority" part as it was obvious a way to get around defining the former by pointing out the latter

I was being flown all over Salisbury plains once in a Blue Eagles Helicopter display team piloted Lynx - interesting experience - often looking at things like Stonehenge etc at some very odd angles - but I digress - one of the passengers asked if the altitude we were at is the same height paratroopers would jump at - the Pilot considered the question and then said yes.....but if they had done better at school they could have stayed with the aircraft.....

Well to continue the digression, (because we all love them so anyway ) I will never forget being in an AC-130 doing "penetration flying" practice where I was strapped into a seat looking DOWN through the door port at the hunter in the forest looking UP at me...

Good times

Randy

 

[gatordad699]

Could but we did love to "quote" that "Competent or Command Authority" part as it was obvious a way to get around defining the former by pointing out the latter



Well to continue the digression, (because we all love them so anyway ) I will never forget being in an AC-130 doing "penetration flying" practice where I was strapped into a seat looking DOWN through the door port at the hunter in the forest looking UP at me...

Good times

Randy

No fun here. We would just “conduct oceanographic research and the ability of the sub to stay deployed for long periods of time.”

 

[RanulfC]

No fun here. We would just “conduct oceanographic research and the ability of the sub to stay deployed for long periods of time.”

I have watched "Down Periscope" and I don't believe your assertion of "No fun"... Besides I know a bunch of Navy and Seebee's so I'm also aware that "no fun" is not an option because you DO get bored...

Randy

 

[thaddeus]

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?

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.

if a number of mobile mines launched in front of convoy they could be timed to explode as well so as not to drift in open Atlantic?

my understanding a paravane or towed mine if released would (or could) rise very rapidly? (layman's understanding) so it could have dual purpose, noisemaker for decoy and once released bring a torpedo after it to the surface? and/or decoy itself a weapon that could strike pursuing ship?

(but have no idea the difficulty of turning RN torpedoes back on them?)

 

[Astrodragon]

if a number of mobile mines launched in front of convoy they could be timed to explode as well so as not to drift in open Atlantic?

my understanding a paravane or towed mine if released would (or could) rise very rapidly? (layman's understanding) so it could have dual purpose, noisemaker for decoy and once released bring a torpedo after it to the surface? and/or decoy itself a weapon that could strike pursuing ship?

(but have no idea the difficulty of turning RN torpedoes back on them?)

Why do this when you already have the pattern-running and acoustic homing torpedoes?

Paravanes are something you usually stream close to harbour to cut moored mines, they don't really work well in bad weather. Especially not North Atlantic Winter sort of bad weather. In any case, you really can't moor a mine in the mid-Atlantic.

 

[McPherson]

if a number of mobile mines launched in front of convoy they could be timed to explode as well so as not to drift in open Atlantic?

In the thread to which I contribute; (See tag) I duplicate a report for a submarine (USS Moondragon) where they encounter a "mobile mine". They easily destroy it, because the mine is observed and blown up by the deck gun. The problem with a mobile mine based on WW II technology is that it is a contact device that has to float.. Torpedoes are devices that swim submerged; that is they use something called "cylinder lift" and power to "fly" through the water. They will actually usually sink once the thrust from the propeller and the lift they get from forward motion stops. The modern mobile mine is a torpedo that drops to the sea floor when it cuts power and becomes a bottom mine set off by a ship that passes close to it to either set it off by wake pressure difference or magnetics or noise or all three influences.

my understanding a paravane or towed mine if released would (or could) rise very rapidly? (layman's understanding) so it could have dual purpose, noisemaker for decoy and once released bring a torpedo after it to the surface? and/or decoy itself a weapon that could strike pursuing ship?

A paravane is an underwater kite towed by a cable. It can act as the control drag for cutting wires as I mentioned or for a special underwater "trumpet" that contains either baffles or free spinning screws that mimic a ship's propeller and engine noise as water flows through the barrel of the noise maker. Some of the devices could carry the equivalent of a small mine designed to explode if a torpedo sets it off by contact or some other influence, but these "active" defenses in noise makers rarely work as intended.

(but have no idea the difficulty of turning RN torpedoes back on them?)

That is sort of confusing. If you mean could a submarine use a paravane? I do not think so. Noisemakers? The submarine, even in world war Ii, used a series of devices called noisemakers. These usually were simple cans ejected out a small tube or series of tubes that contained a chemical compound that reacts with seawater to fizz and produce bubbles. The bubbles did two things. They popped producing lots of noise which could blank sonar in a surprising similar way to the effect a lot of noisy sex starved shrimp could, that is create background noise inside which a quiet sub could hide its own noise; or, create a barrier that reflected sound waves, a kind of mirror similar to the effect that aluminum Chaffe does for aircraft to prevent them from being spotted by a radio beam reflected off of them to radar. IN BOTH CASES, the frequency of the enemy search gear has to be known so that the bubbles' generated or the length of the aluminum strips can be matched to best reflect either the sound waves or the radio beam in the "active defense" mode.

Here's a trick. Did one know that German U-boaters would use something called a "knuckle" to throw off British destroyers' sonars? This was an early dodge. The U-boat if it was fast enough (about eight knots or faster) would make a series of sharp turns to produce lots of hull cavitation and bubbles to create that "bubble curtain" using the sub as the masking method instead of the later "soda cans".

Then there is the underwater version of the rainstorm. Just as a rainstorm made a mess of WW II radar and masked aircraft within, so there is a phenomenon in the ocean called the "thermocline". This is a sharp temperature boundary layer that occurs when different underwater ocean currents flow past each other. US submariners discovered it in the mid 1930s and used it in fleet exercises to "hide" from US "Orange" forces in late fleet problems. How it works is that sound waves like light in certain physical conditions refracts or bends when in the case of sound it passes from warm to cold water. When there is a sharp boundary (like the one produced in the North Atlantic by the Gulf Stream or in the North Pacific by the Japan Current), that bend or refraction is predictable and by comparison to usual ocean condition current boundary layers is sharp. A submarine that knows where the current is and where the boundary is, can hide under the boundary with "relative" safety and use the layer's sound refraction quality to throw off a pursuing destroyer's ranging accuracy with the sonars then in use. It can even creep away under power and pass outside the destroyer signal pickup threshold if the sub captain and tactical plotters have good enough bathythermograph underwater "weather gear" to chart an escape route. Their "cloud" to hide behind, so to speak. It is not perfect. Experienced destroyer skippers know the same trick and can adjust for it, and once things like FIDO come into service, the layer trick becomes less effective. But it is another defense and it is used often. German U-boaters knew about it, the British did and so did the Italians. The Japanese also knew, but both on offense and defense they seemed to not care.

Objectively you can see the results in the terrain where the opponents fought. The Germans (1942 on) used bubble curtains a lot close inshore around the European continent and off the Atlantic American coasts, especially in shallow sandy bottom environments. Americans used the Japan Current and whatever other thermoclines they could find immediately in the West Pacific; because their pre-war doctrine called for something known as the deep submerged sonar target track generated attack based on their fleet exercises results. Their torpedoes were not good enough for that far too modern tactic by the way. Also the West Pacific Basin areas where the Americans had to fight, contain a lot of shallow bottoms: that hard or soft return would not mask well enough a submarine being chased by a Japanese destroyer using derived German or French type Japanese model sonars. The thermocline boundaries were either too shallow or the refraction index was not acute enough to matter, either. So out comes the knuckle tactic. US boats turned like wallowing pigs, but they were FAST for their time underwater. They could knuckle easily. Soda cans come to the Americans late and only after a German U-boat is examined. Never occurred to the Americans.

In the MEDITERRANEAN, the British faced the same exact geographical problems the Americans did in the Pacific. Add to the situation that the Italians were good at all the ASW tricks, too. Heavy and I mean severe British submarine losses, is the result.

Why do this when you already have the pattern-running and acoustic homing torpedoes?

Paravanes are something you usually stream close to harbour to cut moored mines, they don't really work well in bad weather. Especially not North Atlantic Winter sort of bad weather. In any case, you really can't moor a mine in the mid-Atlantic.

I agree with that statement. Want to add that below a certain depth, these underwater kites become a liability as a drag. That cable as it pays out is the reason.

Mooring mines becomes a question of currents and tides. How deep was the Great North Sea Barrage sea floor? Didn't they, the UK and the US, actually have to find an underwater ridge that rose from the North Sea to act as the "floor" for the minefields because the usual North Sea depth was too deep for planting the anchor boxes? The chains were not long enough or would have been so long that they would sink the float heads. Either that or floats would have to supplied for every fifty meters of chain or cable.

 

[thaddeus]

if a number of mobile mines launched in front of convoy they could be timed to explode as well so as not to drift in open Atlantic?

my understanding a paravane or towed mine if released would (or could) rise very rapidly? (layman's understanding) so it could have dual purpose, noisemaker for decoy and once released bring a torpedo after it to the surface? and/or decoy itself a weapon that could strike pursuing ship? (but have no idea the difficulty of turning RN torpedoes back on them?)

Why do this when you already have the pattern-running and acoustic homing torpedoes?

Paravanes are something you usually stream close to harbour to cut moored mines, they don't really work well in bad weather. Especially not North Atlantic Winter sort of bad weather. In any case, you really can't moor a mine in the mid-Atlantic.

A paravane is an underwater kite towed by a cable. It can act as the control drag for cutting wires as I mentioned or for a special underwater "trumpet" that contains either baffles or free spinning screws that mimic a ship's propeller and engine noise as water flows through the barrel of the noise maker. Some of the devices could carry the equivalent of a small mine designed to explode if a torpedo sets it off by contact or some other influence, but these "active" defenses in noise makers rarely work as intended.

That is sort of confusing. If you mean could a submarine use a paravane? I do not think so. Noisemakers? The submarine, even in world war Ii, used a series of devices called noisemakers. These usually were simple cans ejected out a small tube or series of tubes that contained a chemical compound that reacts with seawater to fizz and produce bubbles.

sorry if my posting was confusing (and/or confused) thought a paravane might have worked better against FIDO than the historical countermeasures, and could be released against any pursuing ships if it carried a small mine.

 

[PSL]

Rossler reported ['The U-Boat" pp 120-121] that Kplt Furbringer suggested mini mines deployed from the U-Boat sail to disrupt ASDIC search and attack, in 1936. They were called WAB It was ignored along with pattern running torpedoes and high speed models. In 1938 acoustic mini torpedo was studied plus rocket torpedo + wire guided torpedo; as well as floating mines to deploy ahead of enemy vessels.

 

[McPherson]

Rossler reported ['The U-Boat" pp 120-121] that Kplt Furbringer suggested mini mines deployed from the U-Boat sail to disrupt ASDIC search and attack, in 1936. They were called WAB It was ignored along with pattern running torpedoes and high speed models. In 1938 acoustic mini torpedo was studied plus rocket torpedo + wire guided torpedo; as well as floating mines to deploy ahead of enemy vessels.

Beyond the technology of their day. The grenades would also shatter German GsG and GsF gear aboard the sub. Not to mention that the idea of carrying mines in the sail was a bit "crazy".

Pattern runners were not ignored. As soon as the US grabbed hold of a few German examples, they modified some of their own Mark XIVs and XVIIIs in time to see llimited WW II use. It became standard for post war Mark 16s.

 

[thaddeus]

Rossler reported ['The U-Boat" pp 120-121] that Kplt Furbringer suggested mini mines deployed from the U-Boat sail to disrupt ASDIC search and attack, in 1936. They were called WAB It was ignored along with pattern running torpedoes and high speed models. In 1938 acoustic mini torpedo was studied plus rocket torpedo + wire guided torpedo; as well as floating mines to deploy ahead of enemy vessels.

wondered if a hybrid torpedo would work, with battery to propel it away from boat and steam for second stage at faster speed? but the electric torpedo closed gap on speed during the war so it might not be worth efforts?

 

[McPherson]

wondered if a hybrid torpedo would work, with battery to propel it away from boat and steam for second stage at faster speed? but the electric torpedo closed gap on speed during the war so it might not be worth efforts?

To be honest, it is asking a lot of either German, British, French, Russian, Italian or American engineers to work out the kinks of an electric torpedo. There were three solution tracks available, Silver-zinc or silver magnesium seawater batteries, nickel cadmium batteries or lead-sulfuric or hydrochloric acid batteries. All three approaches were of an order of magnitude equivalent to designing a brand new four engine bomber or designing a complete new tank. If anything a torpedo is more difficult because even the littlest mistake and one winds up with a failure.

Witness the Mark XIII, XIV and XV, steam driven types, that the USN tried to field after 20 years of development? It still took 2 years during the war and another 5 years postwar to fix them.

FIDO, a lead acid battery powered torpedo which worked was an 18 month program that was frankly "a miracle". It sort of worked. Needed 10 years more work to finally field a good ASW torpedo that could be air dropped and be considered reliable.

The Mark XVIII which was a US nuts and screws copy of a German G7e, was put into service in 2 years because the Germans had spent 10 years of their own work solving all the major problems of a lead acid electric power unit. This power unit was US duplicated exactly to the service busses and was mated to a Mark XIV front end, and scaled down to fit inside an American torpedo tube. It worked, but the battery cells leaked more than the Siemens designed originals and the smaller American torpedo had an inferior gyro set-up control and weaker batteries. It was slower, more fragile, than the German original and the darned thing retained the Mark XIV's nasty habit of circling back on the sub that launched it. This meant a not too fast short ranged weapon that could sink a freighter if the nose wander problem did not steer it to miss ahead or astern; but was almost useless in a destroyer/sub duel unless the destroyer captain was incredibly stupid. Cutie which was an electric FIDO for subs to kill destroyers could get it done, but it was slooooower than the Mark XVIII. An attempt to make a Sound King (ZaunKonig) version of the Mark XVIII failed.

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The Mark 48, the current US heavyweight torpedo, which uses a liquid mon-oxidant-fuel, was started in 1947 and was not cleared for service until 1978. It's predecessor, the Mark 37 sub-killer was a 25 year horror show before it became reliable. To show you what it really means, the USN keeps stocks of WW II developed torpedoes still in her inventory, because after 70+ years of use and tinkering, those weapons are known to work, or at least their faults are understood so that they can be made to work.
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The US did develop a seawater (silver chloride zinc) battery power unit for a torpedo for testing in 1943, but the silver the Navy needed to finally complete the program had been scarfed up by the Manhattan Project. It would not have mattered if the USN had been allotted the 100 tonnes of silver requested, because the torpedo (Mark 32===> 37) was not ready until 1958. And then it took another 15 years to get it to work right. Just in time for the Mark 48 to replace it.

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The French during the Vichy years started work on nickel cadmium battery units. They had their power units fairly quickly (1955) but they had a lot of issues to solve with handling and stowage. As soon as they could they switched over to silver, or their own version of OTTO fuel. Safer.

The Russians duplicated US work with NAVOL. This has not worked out too well, as they have lost two submarines to torpedo accidents. The Chinese who have used Russian tech have at least one NAVOL torpedo loss of submarine disaster of their own. The USN has had several close calls. NAVOL is not in US service anymore (I hope.)

 

[pdf27]

Did anybody ever get nitric acid oxidiser to work in a torpedo? It seems like it ought to be a bit safer than hydrogen peroxide (NAVOL) but I can hardly find any references to it being used.

 

[McPherson]

Nitric acid has its own considerable problems that makes hydrogen peroxide a slightly "safer" alternative.

 

[thaddeus]

Did anybody ever get nitric acid oxidiser to work in a torpedo? It seems like it ought to be a bit safer than hydrogen peroxide (NAVOL) but I can hardly find any references to it being used.

Nitric acid has its own considerable problems that makes hydrogen peroxide a slightly "safer" alternative.

a good wiki article https://en.wikipedia.org/wiki/Red_fuming_nitric_acid

it was my understanding that Wasserfall rocket was to use SV-Stoff because it could remain at the ready for extended period, thus my question would it have been better in the ME-163?

 

[Sam R.]

Three quick points:

what the germans need is the XXI to be in service by ***1843***

I concur.

and the Russians will be in Berlin on schedule as in the RTL.

Perhaps, but with lost lend lease tonnage in trucks radios locos and copper cable, with an even worse gender balance, fewer remaining second line units, and more executions for vengeance after the three days are up.

Finally the standard Australian employment contract for civvies includes “other duties as required.” Its rare youse sailors got more formal rights than ordinary workers.

 

[McPherson]

a good wiki article https://en.wikipedia.org/wiki/Red_fuming_nitric_acid

it was my understanding that Wasserfall rocket was to use SV-Stoff because it could remain at the ready for extended period, thus my question would it have been better in the ME-163?

Nitric acid has its own considerable problems that makes hydrogen peroxide a slightly "safer" alternative.

That's a happy mix. One whiff and your lungs turn to charred carbon.

 

[pdf27]

That's a happy mix. One whiff and your lungs turn to charred carbon.

I was assuming commercial-grade acid (68% max), which doesn’t fume. Rockets are weight-critical in a way torpedoes are not. It’s nasty, but dealt with in commercial quantities all the time.

I know the soviets built a nitric acid/turpentine weapon in 1936 and the UK also considered it, so it isn’t totally batty - http://discovery.nationalarchives.gov.uk/details/r/C529079

 

[AJE]

That's a happy mix. One whiff and your lungs turn to charred carbon.

It's still possible to use red fuming nitric acid- anyone who was shot at by SA-2s in Vietnam and everyone who has used Scuds, SA-2s, and SA-5s to this day can attest to that. But the use of toxic fuels was the number one complaint the Soviets had for those weapons and they were replaced as soon as possible. There were still some engineers who advocated toxic storable propellants, including one who notoriously proposed to use them (specifically N2O4/UDMH) to power a rocket big enough for a manned mars mission, but fortunately that plan didn't go anywhere.

 

[Astrodragon]

Remember that anything you have in a sub will leak (often copiously) as soon as it gets depth charged.
So anything corrosive is a bad idea.

Also, a point - Italian ASW wasn't that good, a lot of the RN boats were lost to mines. The Italians were the best of the Axis A/S forces though.