Kriegsmarine Ship X

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Paul Lakowski
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Re: Kriegsmarine Ship X

#46

Post by Paul Lakowski » 16 Nov 2016, 05:47

Through out the war the KM was overflowing with tankers [33 in 1939 to 60 in 1944] , and a large portion those were 15-16 kts - more than enough for U-Boat fleet. The HSK could already sail for 60,000nm [~ 180 days] so they did not need much replenishment. The only thing tankers with much more speed would be needed for would be to accompanying fast warships in action. They could manage 27 knots- but could only carry 7000 tons fuel & provisions.

The 25kt P-CLASS PANZERSCHIFFE was what a 20kt D CLASS PANZERSCHIFFE could be -with enough fuel to complete 3 months at sea with out refueling. D CLASS PANZERSCHIFFE was what a 16kt GRAFF SPEE would function like- if it had speed.

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Re: Kriegsmarine Ship X

#47

Post by thaddeus_c » 18 Nov 2016, 04:54

Paul Lakowski wrote:Through out the war the KM was overflowing with tankers [33 in 1939 to 60 in 1944] , and a large portion those were 15-16 kts - more than enough for U-Boat fleet. The HSK could already sail for 60,000nm [~ 180 days] so they did not need much replenishment. The only thing tankers with much more speed would be needed for would be to accompanying fast warships in action. They could manage 27 knots- but could only carry 7000 tons fuel & provisions.

The 25kt P-CLASS PANZERSCHIFFE was what a 20kt D CLASS PANZERSCHIFFE could be -with enough fuel to complete 3 months at sea with out refueling. D CLASS PANZERSCHIFFE was what a 16kt GRAFF SPEE would function like- if it had speed.
that is large number of tankers cited, is that after seizure of Vichy French and Italian fleets? my scenario is for an expanded version of what was employed historically, u-boats, HSK, and supply ships (after of course the PBs had been sunk or retreated to home water.)

the u-boats can dive, the HSK rely on disguise, if the Dithmarschen-class were just a bit faster they could have outrun almost anything? they were also technically a supply ship, during German-Soviet cooperation KM was going to be allowed a floating base in the Pacific at Petropavlovsk (Soviets thought Vladivostok too overt.)

not positive about ever larger Panzerschiffe, relative to resources invested. if the auxiliary cruisers and u-boats were built out it might be unnecessary and some type of (coal powered?) heavily armed and armored coastal battleships built (or rebuilt from existing fleet?) to fend off Allies?


Paul Lakowski
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Re: Kriegsmarine Ship X

#48

Post by Paul Lakowski » 18 Nov 2016, 20:46

Tanker figures are the historical figures from OIL & BLOOD.

Sounds fine with a couple of caveats...as long as UK remains in the war allied air power will neutralize and ultimate destroy any large warships prior to invasion. best solution is to invade UK or interdict the life line to America. Pre war U-boat fleet is doable but political dynamite. Koop & Schmolke discussed -in their warship volumes - that ex KM designers revealed in 1957 that the recourses/shipyards/funding that was sunk into the KM BATTLEFLEET [4 BB & 5 CA] could instead have built either 21 Deutschland PBS or 375 type VII U-Boats.

But if you were to expect major Allied opposition - it would be much more if the KM had opted for U-Boats . Further the German battery industry needed 2-3 war years to historically to generate the tonnage needed to build a large U-boat Fleet. I have no clue how much that would cost prewar funding and the impact of those shifting resources...what ever they may be?

I have a reasonable good grasp of the limitations of building a large PBS fleet ....and it IS mostly doable ....and still build a small U-Boat fleet.

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Re: Kriegsmarine Ship X

#49

Post by thaddeus_c » 19 Nov 2016, 17:41

Paul Lakowski wrote:Sounds fine with a couple of caveats...as long as UK remains in the war allied air power will neutralize and ultimate destroy any large warships prior to invasion. best solution is to invade UK or interdict the life line to America. Pre war U-boat fleet is doable but political dynamite. Koop & Schmolke discussed -in their warship volumes - that ex KM designers revealed in 1957 that the recourses/shipyards/funding that was sunk into the KM BATTLEFLEET [4 BB & 5 CA] could instead have built either 21 Deutschland PBS or 375 type VII U-Boats.

But if you were to expect major Allied opposition - it would be much more if the KM had opted for U-Boats . Further the German battery industry needed 2-3 war years to historically to generate the tonnage needed to build a large U-boat Fleet. I have no clue how much that would cost prewar funding and the impact of those shifting resources...what ever they may be?
they could have probably negotiated a larger submarine force (posed as counterweight to huge Soviet force?) although my scenario was not projecting 300 u-boat fleet at onset of war but rather a combined fleet that (possibly) would make u-boat fleet more effective.

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Re: Kriegsmarine Ship X

#50

Post by Paul Lakowski » 19 Nov 2016, 20:48

just before the war- there was talk of pushing for > 100 U-Boats and worrying about the treaty consequence's later, that could not have happened until 1940 or later in peace time.

If you go strictly by historical U-Boat tonnage; 220 type II U-Boats could be completed by the end of 1940 [107ABC+113 D]. The battery tonnage could allow for 230 x Type II U-Boats. To get 230 Type II ,most have to be Type II A/B/C , but with few type IID. The critical difference there becomes small range. Type II ABC models had ranges of only 1080 to 1900nm @ 12 knots on surface, while the D model had straddle tanks and could manage 3400nm@ 12 knots.

To be fair the early models could also cruise 3100-3800 @8 knots. So initially transit to the UK could require 300- 800nm either way leaving 1/2-3/4 of endurance on patrol. Having said that the D model could cruise 5600nm @ 8 knots , So they could patrol 3/4 of the time off the FAROES ISLANDS!

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Re: Kriegsmarine Ship X

#51

Post by thaddeus_c » 24 Nov 2016, 17:01

Paul Lakowski wrote:
thaddeus_c wrote:Historically up to the end of 1940 ~610,000 tons was invested in Hitler's incomplete war fleet, with 64,000 to U-Boats & another 100,000 on the escort fleet and 110,000 for special tankers....which left ~ 400,000 tons for the battle fleet .

2 x 51kt BB
2 x 39kt BB
5/3 x Ca [total planned 96kt /actual 89kt ]
0/2 CV [total planned 67kt /actual 34kt]
0/2 11kt CL [total planned 22kt /actual 2kt ]
build Admiral Hipper-class with two forward facing 11" gun turrets to counter the French, possibly converting last 2 to carriers.

instead of ~40 destroyers and ~40 torpedo boats build a larger hybrid propulsion ship capable of Atlantic operations, something around 6,000kt, off of which destroyers, minelayers, and fleet tenders finished (a Ship X)

build 2 - 4 of SOME type of carrier (Japanese seaplane carrier Nisshin https://en.wikipedia.org/wiki/Japanese_ ... er_Nisshin ??)

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Re: Kriegsmarine Ship X

#52

Post by Paul Lakowski » 24 Nov 2016, 22:01

SEA plane carriers are of limited value since they can only be used in calm seas which is not frequent in the N. Atlantic....maybe one day in 4...what do you do for the rest of the time?.

KM had plans to build a line of SPAHKREUZER , and if the ZPLAN is any indication they could manage~ 3 per year after 3 years work and 5 per year after 5 years of production, with the increase at the expense of other DD/TB.



SO IF 1936 Start [4 year plan] = 3/39 = 6/40 = 9/41 = 12/42 = 15/43 = 20/44 = 25/45

based on historical this might have to be INSTEAD of DD/TB.

http://navypedia.org/ships/germany/ger_dd_194041.htm

GOOD SHIP but more of an escort that stand alone raider. With out all diesel , its not likely to manage more than 4000nm @19kts, Which limits it to north of GIUK gap.On diesel it should make 7-8000nm @ 19 [North Atlantic ops] , but top speed is likely to be only 34-35 knots.

The 150 meters is good , but 14m beam makes conversion to CVE difficult especially with small freeboard.

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Re: Kriegsmarine Ship X

#53

Post by thaddeus_c » 25 Nov 2016, 15:01

my scenario was to scrap ALL destroyers and torpedo boats and instead build off an enlarged platform, when a larger destroyer for Atlantic operations was first projected the figure was 4,900kt which of course grew to over 7,500kt in Plan Z.

(confused the issue somewhat by projecting 8 (?) minelayers with wider beam but same engine layout, "built off same platform" is probably not correct term to use?)

was calculating they would not lag behind historical destroyer production? maybe even exceed it a bit as the 4 large turbine BBs are deleted and instead construct Admiral Hipper-class as largest ships?

was speculating the 2 Graf Zeppelin-class carriers might have multiple roles as did Japanese seaplane carrier Nisshin not give up their flight deck but rather add ability to handle (some small contingent) seaplanes and/or small fast attack boats.

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Re: Kriegsmarine Ship X

#54

Post by Paul Lakowski » 26 Nov 2016, 06:49

Admiral Carls is probably the only one of the prewar leaders who had a grasp of the task at hand. He advocated integrated naval /air forces. Kaptain Furbringer did insist of integrating LW into the U-B0at war although not sure how this was to work. Carls on the other had does.

His proposal [which was dismissed as hubris] was to form integrated battle groups composed of .....

1 AIRCRAFT CARRIER
1 BATTLE KREUSER
1 HEAVY KREUSER
SEVERAL FLOTILLA OF ZERSTROYERS
TANKERS & SUPPLY SHIPS.

ALL THIS WOULD BE TO DIRECT AND SUPPORT A NUMBER OF U-BOAT FLOTILLA.[WOLF PACK?]

As I understand it -wolf packs were ad-hock groups formed from what ever U-Boats were in the area. The above list of ships could never breakout as a group- but a number could get through in some organized breakout attempt and then form up later bas ad hock groups. So if we're to break down these components ,

The carrier is obviously for long range scouting for convoys and local air defense.

The Battle Kreuzer & Heavy Kreuzer could be for carrier escort , but they would be more valuable striking the detected convoys to neutralized the convoy escorts...making it easier for the U-boats to attack.

Surely the Zerstroers are to escort the carriers & supply ships/tankers.

HOWEVER OBVIOUS THINGS LEAP OFF THE SCREEN , like the Zerstroers would never have the range or reliability to escort anything into the N. Atlantic. The Battle Kreuzer & Heavy Kreuzer look like duplication - except the Hipper class also didn't have the legs for Atlantic ops with out a dedicated tanker following.

For the tonnage of Scharnhorst & Hipper WARSHIPS, you could get 3 diesel PANZERSCHIFFE instead. AND IF you factor in Graf Zeppelin as well you could get 5 x diesel PANZERSCHIFFE instead.

For scouting role, double the number of CONDOR MARITIME PATROL PLANES would go along way to detecting convoys. But then B-Dienst code breaking was detecting at least 1/3 of the convoys in N. Atlantic from late 1941-late 1943....one could argue that an a aircraft carrier is not needed in the short term and an escort carrier is all your need later on. An escort carrier could be improvised from conversion of a captured enemy cruiser.. may take a couple of years [1942/43?] .

BUT HERES THE KICKER. If Admiral Carls force is to orchestra several wolf packs, say 3-4 [30-40 U-boats] by early in the war there are 40-100 U-Boats [4 to 10 wolf packs] . THAT COULD 1/2 DOZEN OF CARLS GROUPS ...TOO MEET ROTATION NEEDS. By mid war the number of Front boot is 130-200 or up to 20 wolf packs. That suggest a need for UP TO A DOZEN CARLS GROUPS!!!!

AND THAT DOEST TAKE ACCOUNT OF LOSSES.

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Re: Kriegsmarine Ship X

#55

Post by thaddeus_c » 27 Nov 2016, 16:09

Admiral Carls' plan does seem outsized for the resources available but guess the same could be said for Plan Z?

my idea for Ship X large destroyers and minelayers capable of Atlantic operations did not envision such operations taking place absent H-class battleships (so basically never.) however a ship hovering around 6,000kt seemed a good platform for 5.9" guns which the historical Zerstorers proved NOT to be? and minelayer version could carry 400 mines so a pair (my design minelayer and destroyer) could perform operation that required (up to) six destroyers and light cruiser escort.

was projecting Admiral Hipper-class as faster successor to PBs? not better armored ones. not sure how they would fare against French Dunkerque let alone RN but there would/could be 4 - 5 so they could operate in two pairs.

both of the Italian carrier projects were conversions (of ocean liners) maybe that would have been better plan for KM at least as their initial project?

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Re: Kriegsmarine Ship X

#56

Post by Paul Lakowski » 27 Nov 2016, 22:41

Spähkreuzers were a tempting design and would definitely work if these convoy's were only covered by DD, but they always included cruisers of one description or another. Worse there was often heavier forces as "distance cover" for a number of convoys. Through the middle of the war , 4 convoys a week were sailing the N. Atlantic lanes, so this covering force could be substantial.

I just don't think Spähkreuzers will be enough? Since the allies had substantial number of light cruisers anyway, such a raider needs to be able to defeat such cruisers.

The German navy building resources invested from 1934-1944 could build a sizable forces of large warships of cruiser sized or bigger, but in order to attack convoys these cruisers need to be better armed & protected than the expected convoy escorts. That means redirecting all the resources that were historically devoted to Destroyer Torpedoboot, Fleet tenders ; Dithmarschen tankers - along with all the tonnage invested in Air Craft Carriers- Battleship- Battle Cruiser & Hipper Kreuzers. Over 40 such cruisers could have been built instead through out the war -with 1/2 completed by 1940.

BTW the KM deployed 225,000 mines during the war and sank 534 Merchant Vessels or 421 mines per ship sunk.

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Re: Kriegsmarine Ship X

#57

Post by thaddeus_c » 01 Dec 2016, 04:10

Paul Lakowski wrote:The German navy building resources invested from 1934-1944 could build a sizable forces of large warships of cruiser sized or bigger, but in order to attack convoys these cruisers need to be better armed & protected than the expected convoy escorts. That means redirecting all the resources that were historically devoted to Destroyer Torpedoboot, Fleet tenders ; Dithmarschen tankers - along with all the tonnage invested in Air Craft Carriers- Battleship- Battle Cruiser & Hipper Kreuzers. Over 40 such cruisers could have been built instead through out the war -with 1/2 completed by 1940.
still think the u-boat fleet matched their resources and personnel better, only lacking evolutionary changes to the u-boats and a support system for operations.

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Re: Kriegsmarine Ship X

#58

Post by Paul Lakowski » 01 Dec 2016, 04:58

thaddeus_c wrote:
Paul Lakowski wrote:The German navy building resources invested from 1934-1944 could build a sizable forces of large warships of cruiser sized or bigger, but in order to attack convoys these cruisers need to be better armed & protected than the expected convoy escorts. That means redirecting all the resources that were historically devoted to Destroyer Torpedoboot, Fleet tenders ; Dithmarschen tankers - along with all the tonnage invested in Air Craft Carriers- Battleship- Battle Cruiser & Hipper Kreuzers. Over 40 such cruisers could have been built instead through out the war -with 1/2 completed by 1940.
still think the u-boat fleet matched their resources and personnel better, only lacking evolutionary changes to the u-boats and a support system for operations.

With mass production/economy of scale; from the mid 1930s on ~ 220 x type II U-Boats can be completed by the end of 1940. After that - a series of 800 x Type IX U-Boat could be completed through the end of 1944; with another 250 in 1945: if the war lasted that long. But unless the U-Boats evolve- the out come of 'the war at sea' will not change that much.

One change I would definitely advocate would be to kick Admiral Donitz up to U-Boat development with Dr Walther to develop super fast under water subs with long endurance plus the sonars and torps to go with it. I would leave the U-Boat war to Kaptain/Admiral Furbringer.

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Re: Kriegsmarine Ship X

#59

Post by kfbr392 » 14 Feb 2017, 23:28

isn't any attempt to beat the Allies at the high-end surface warfare game a vain endeavour? Competing means spending huge resources on ever larger types and yet remain numerically inferior and the hunted.

Is the answer not asymetry and "smallness"?
true fast u-boat, s-boat, HSK raider, coal fired m-boat, torpedo and mine with advanced fuses, superior aircraft, rail-transportable landing craft (PiLB, PiLF, MAL II, StuBo), KFK, K-Verband (frogmen, Sprengboot Linse, etc), ...

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Re: Kriegsmarine Ship X

#60

Post by Paul Lakowski » 15 Feb 2017, 05:13

No the historical fleet conformed to HITLERS demand that the navy be nothing more than a coastal defence fleet with limited aspiration's in the Baltic & North Sea /Norwegian Sea...so as not to threaten the UK. The 1930s KM strategic discourse accepted only a large U-Boat fleet could wage the kind of commerce warfare needed to cut the American life line to Europe [as per WW-I] and isolate the UK.

However the U-Boat war was always going to be a one dimensional threat which could be defeated given enough time. Other angles /dimensions had to be established. Furbringer stressed the Luftwaffe and Thaddeus & I were discussing expanded FW 200 CONDORS production in place of the bulk of the numerous seaplane production runs. This works reasonably well until the end of 1942.

The bulk of KM warship construction after the U-BOAT FLEET went into this coastal defence fleets - while the big gun industry was redirected to beef up the "ATLANTIC WALL". They tolled all war only to have those forces swept aside in a matter of months by overwhelming allied air/sea forces. A Total waste of resources construction & fuel !!!

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