AHC: Different Deutschland-class Panzerschiffe for Reichsmarine

[Sargon]

Thanks for that. I reconsidered as a result, and my new request is in post 41.

Also, great seeing you here! Loved what you did with my girl Warspite in Hippodrome.

Looking at the new request, although it is possibly doabale, it's going to be expensive for what is just a cruiser killer. That's not a small ship and not a small crew. You'll probably only get three of them at most. It'll probably do its job though, as long as the captains in charge of them strictly follow orders or they don't find themselves in a situation they can't get out of (which you just know given the KM's luck will probably happen at some point).

Thanks. Ah, my story as referenced in my sig. Well, that's just part of the utter mayhem Warspite is going to wind up being in the middle of. Glad you are liking it so far.


Sargon

 

[alfredtuomi]

practical question.......how long does it take to bring on line the steam turbines to boost the diesel cruising speed from 20 knots to the escape speed of 30+ knots....hmmm....answer....probably longer than the closing speed of Repulse/renown/hood/all those heavy and light cruisers travelling in packs after first siting.the realities of steam plants kinda throws a damper on a combined propulsion unit(and keeping all the boilers on standby for quick acceleration kills any economy savings of diesels).

 

[Kantai Kessen]

Looking at the new request, although it is possibly doabale, it's going to be expensive for what is just a cruiser killer. That's not a small ship and not a small crew. You'll probably only get three of them at most. It'll probably do its job though, as long as the captains in charge of them strictly follow orders or they don't find themselves in a situation they can't get out of (which you just know given the KM's luck will probably happen at some point).

I only want two of them built in the late 1920s/early 1930s instead of the three Deutschlands, so that should be fine. Same number of turrets means the build process should be fine.

Given the KM's lack of initiative in terms of officers, I think these should serve. Perhaps I should call them Scharnhorst and Gneisenau...

And this will force the OTL Dunkerques to be built as counters by the French.

 

[Kantai Kessen]

practical question.......how long does it take to bring on line the steam turbines to boost the diesel cruising speed from 20 knots to the escape speed of 30+ knots....hmmm....answer....probably longer than the closing speed of Repulse/renown/hood/all those heavy and light cruisers travelling in packs after first siting.the realities of steam plants kinda throws a damper on a combined propulsion unit(and keeping all the boilers on standby for quick acceleration kills any economy savings of diesels).

This is a good point. Hence why I only want sole diesel propulsion.

 

[Kantai Kessen]

Kantai,

When Warship Projects 3.0 was active, our member Jefgte posted several panzarschiffe alternative models he scratchbuilt in our Never-were Models forum.
Warship Projects no longer exists (it was hacked and destroyed) but I recently found Jef had also posted on The Ship Model Forum. I cannot view his images on those threads, but if you are interested, you can get some idea of his alternate panzarschiffe ideas from these threads:

The Ship Model Forum • View topic - 1/700 Panzerschiffes Study 2 ,6 & 8

The Ship Model Forum • View topic - 1/700 Pocket Battleships Study 14 & 15

He included a spring sharp sim of his Study 5 in this thread

The Ship Model Forum • View topic - What-if Deutschland WW2 Panzerschiffe

Regards,

I can't view the images either, but thanks - this is helpful!

What do you think about my post 41 design?

 

[Paul_Sussex]

Might also be worth looking at some of the "never built" designs in Shipbucket?

 

[Kantai Kessen]

Might also be worth looking at some of the "never built" designs in Shipbucket?

Thanks - I'll check those out.

 

[thaddeus]

practical question.......how long does it take to bring on line the steam turbines to boost the diesel cruising speed from 20 knots to the escape speed of 30+ knots....hmmm....answer....probably longer than the closing speed of Repulse/renown/hood/all those heavy and light cruisers travelling in packs after first siting.the realities of steam plants kinda throws a damper on a combined propulsion unit(and keeping all the boilers on standby for quick acceleration kills any economy savings of diesels).

their hybrid system historically was basically a steam turbine ship with (relatively) small diesel they employed to extend the range, with the later Leipzig and Nurnberg there was no "coupling and/or de-coupling" mechanical process, they did have a "several minutes" downtime though.

the German CLs do not show a great range at first glance however their fuel stores were much less, when they finally began a class with somewhat comparable fuel, M-class cruisers, their range approached that of the Panzerschiffe, and it could reach 35 knots vs. the 28 knots of the Deutschlands.

 

[alfredtuomi]

their hybrid system historically was basically a steam turbine ship with (relatively) small diesel they employed to extend the range, with the later Leipzig and Nurnberg there was no "coupling and/or de-coupling" mechanical process, they did have a "several minutes" downtime though.

the German CLs do not show a great range at first glance however their fuel stores were much less, when they finally began a class with somewhat comparable fuel, M-class cruisers, their range approached that of the Panzerschiffe, and it could reach 35 knots vs. the 28 knots of the Deutschlands.

engaging turbine power isn t the issue,firing the boilers and bringing the turbines online is.basically you are heating up metal and if forced you damage them.

 

[1Big Rich]

I can't view the images either, but thanks - this is helpful!

What do you think about my post 41 design?

I think 20,000 tons should be possible, 25,000 might make things easier, but then with a larger ship, more hitting power might be desirable? I'll attempt a Spring Sharp of the idea later.

Funny thing about your idea; I've been working off and on writing some fiction where a modernized Lion and reconstructed Princess Royal are hunting a 20,000+ ton panzarschiffe with 6 x 35cm in late 1939...

Regards,

 

[thaddeus]

engaging turbine power isn t the issue,firing the boilers and bringing the turbines online is.basically you are heating up metal and if forced you damage them.

yes, I understand your point, mine was that we are talking about ships that were largely viewed as steam turbine vessels (which comprised the near totality of warships at the time), do not believe they planned to "crawl" with the diesel engine except in cases where they would have a long horizon?

a "bad compromise" due to the ceiling on the speeds they could achieve with diesels.

 

[Kantai Kessen]

I think 20,000 tons should be possible, 25,000 might make things easier, but then with a larger ship, more hitting power might be desirable? I'll attempt a Spring Sharp of the idea later.

Funny thing about your idea; I've been working off and on writing some fiction where a modernized Lion and reconstructed Princess Royal are hunting a 20,000+ ton panzarschiffe with 6 x 35cm in late 1939...

Regards,

Yeah, I basically want to keep the ship as small as possible with these requirements.

Now that sounds like an interesting TL... what happened? (And I hope this doesn't derail the thread )

 

[Kantai Kessen]

yes, I understand your point, mine was that we are talking about ships that were largely viewed as steam turbine vessels (which comprised the near totality of warships at the time), do not believe they planned to "crawl" with the diesel engine except in cases where they would have a long horizon?

a "bad compromise" due to the ceiling on the speeds they could achieve with diesels.

Given the Leipzig engine design was laid down just two years after the K-class started production, perhaps the Germans should have waited...

 

[vizzer]

Looking at the new request, although it is possibly doabale, it's going to be expensive for what is just a cruiser killer.

Although why would the Germans want a cruiser killer surely a raider should run from trouble not seek it out.
Guns suitable to deal with merchant vessels & perhaps light cruisers otherwise sufficient engine power/speed to outrun enemy vessels & sufficient armour to survive heavy cruiser shells until out of range.
If it stands to fight even if victorious it probably takes sufficient damage to be mission killed anyway.

 

[alfredtuomi]

yes, I understand your point, mine was that we are talking about ships that were largely viewed as steam turbine vessels (which comprised the near totality of warships at the time), do not believe they planned to "crawl" with the diesel engine except in cases where they would have a long horizon?

a "bad compromise" due to the ceiling on the speeds they could achieve with diesels.

Then why have diesels?

 

[marathag]

Although why would the Germans want a cruiser killer surely a raider should run from trouble not seek it out.
Guns suitable to deal with merchant vessels & perhaps light cruisers otherwise sufficient engine power/speed to outrun enemy vessels & sufficient armour to survive heavy cruiser shells until out of range.
If it stands to fight even if victorious it probably takes sufficient damage to be mission killed anyway.

For sinking merchantmen, they could have just fitted pneumatic 'Dynamite Guns' on broadside to chuck thinwall explosive charges over a mile distant.
That saves on not needing to expend 'real' ammunition on targets that don't require 150mm attention.

 

[Peg Leg Pom]

Although why would the Germans want a cruiser killer surely a raider should run from trouble not seek it out

Cruiser killers are essentially anti commerce raiders so why Germany of all nations would want them I don't know. What Germany needs are coast defence ships and armed merchants for raiding, not big expensive ships that will draw the attention of the combined British and French navies every time they leave port and be hunted to destruction at the earliest possible opportunity.

 

[NoMommsen]

Then why have diesels?

... RANGE !

Cruiser killers are essentially anti commerce raiders so why Germany of all nations would want them I don't know.

... for killing cruisers ;-)

1. to enable own blockade runners to come through by distracting and/or destroying the enemies cruisers hunting theses blockade runners
2. to destroy cruisers hunting you the raider/Panzerschiff itself

What Germany needs are coast defence ships and armed merchants for raiding, ...

... what about international law ) ... won't such merchant raiders violate it ?

... not big expensive ships that will draw the attention of the combined British and French navies ...

... I somehow have the feeling the lack of any 'Big Ships' would make the British and French Navies even more suspisious (at least some ... members on this forum might argue this way) and their 'James Bonds' of the time would certainly HAVE and do find something.
... if only to give money spending for naval armament some reason.

 

[1Big Rich]

Yeah, I basically want to keep the ship as small as possible with these requirements.

Attempt at a sim. 20,000 tons light (I doubt the Germans would build to Washington Standard). She's too big for a pocket

Graf Tauentzien, Kantai Germany Sachel Battleship laid down 1929

Displacement:
20,017 t light; 20,938 t standard; 26,370 t normal; 30,716 t full load

Dimensions: Length overall / water x beam x draught
716.62 ft / 714.00 ft x 83.00 ft x 26.00 ft (normal load)
218.43 m / 217.63 m x 25.30 m x 7.92 m

Armament:
9 - 11.14" / 283 mm guns (3x3 guns), 661.40lbs / 300.01kg shells, 1929 Model
Breech loading guns in turrets (on barbettes)
on centreline ends, majority forward, 1 raised mount - superfiring
8 - 5.91" / 150 mm guns in single mounts, 100.30lbs / 45.50kg shells, 1929 Model
Quick firing guns in deck mounts
on side, all amidships
4 - 3.46" / 88.0 mm guns (2x2 guns), 19.80lbs / 8.98kg shells, 1929 Model
Anti-aircraft guns in deck mounts
on side, evenly spread, all raised mounts
2 - 3.46" / 88.0 mm guns (1x2 guns), 19.80lbs / 8.98kg shells, 1929 Model
Anti-aircraft guns in deck mount
on centreline aft, all raised guns - superfiring
12 - 1.46" / 37.0 mm guns (6x2 guns), 1.55lbs / 0.70kg shells, 1929 Model
Breech loading guns in deck mounts
on side, evenly spread, all raised mounts
Weight of broadside 6,892 lbs / 3,126 kg
Shells per gun, main battery: 100

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 8.00" / 203 mm 410.00 ft / 124.97 m 13.00 ft / 3.96 m
Ends: Unarmoured
Main Belt covers 88 % of normal length

- Torpedo Bulkhead:
1.00" / 25 mm 400.00 ft / 121.92 m 20.00 ft / 6.10 m

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 11.0" / 279 mm 6.00" / 152 mm 10.0" / 254 mm
2nd: 2.00" / 51 mm - -

- Armour deck: 3.75" / 95 mm, Conning tower: 11.00" / 279 mm

Machinery:
Diesel Internal combustion motors,
Direct drive, 4 shafts, 102,712 shp / 76,623 Kw = 29.00 kts
Range 12,000nm at 20.00 kts
Bunker at max displacement = 9,778 tons

Complement:
1,034 - 1,345

Cost:
£7.589 million / $30.357 million

Distribution of weights at normal displacement:
Armament: 899 tons, 3.4 %
Armour: 6,805 tons, 25.8 %
- Belts: 1,848 tons, 7.0 %
- Torpedo bulkhead: 296 tons, 1.1 %
- Armament: 1,446 tons, 5.5 %
- Armour Deck: 3,004 tons, 11.4 %
- Conning Tower: 210 tons, 0.8 %
Machinery: 3,155 tons, 12.0 %
Hull, fittings & equipment: 9,059 tons, 34.4 %
Fuel, ammunition & stores: 6,353 tons, 24.1 %
Miscellaneous weights: 100 tons, 0.4 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
43,094 lbs / 19,547 Kg = 62.3 x 11.1 " / 283 mm shells or 5.8 torpedoes
Stability (Unstable if below 1.00): 1.28
Metacentric height 5.9 ft / 1.8 m
Roll period: 14.3 seconds
Steadiness - As gun platform (Average = 50 %): 53 %
- Recoil effect (Restricted arc if above 1.00): 0.41
Seaboat quality (Average = 1.00): 1.15

Hull form characteristics:
Hull has a flush deck
Block coefficient: 0.599
Length to Beam Ratio: 8.60 : 1
'Natural speed' for length: 26.72 kts
Power going to wave formation at top speed: 51 %
Trim (Max stability = 0, Max steadiness = 100): 46
Bow angle (Positive = bow angles forward): 5.00 degrees
Stern overhang: -2.00 ft / -0.61 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 30.00 ft / 9.14 m
- Forecastle (20 %): 19.00 ft / 5.79 m
- Mid (50 %): 19.00 ft / 5.79 m
- Quarterdeck (15 %): 19.00 ft / 5.79 m
- Stern: 19.00 ft / 5.79 m
- Average freeboard: 19.88 ft / 6.06 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 86.3 %
- Above water (accommodation/working, high = better): 151.6 %
Waterplane Area: 43,303 Square feet or 4,023 Square metres
Displacement factor (Displacement / loading): 129 %
Structure weight / hull surface area: 146 lbs/sq ft or 714 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 1.00
- Longitudinal: 1.03
- Overall: 1.00
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is excellent

100 tons flag facilities, aircraft, hangar, catapult, boom on mainmast

Now that sounds like an interesting TL... what happened? (And I hope this doesn't derail the thread )

I don't know, the story hasn't gotten that far yet. But neither battlecruiser has radar....

Regards,

 

[thaddeus]

we are talking about ships that were largely viewed as steam turbine vessels (which comprised the near totality of warships at the time), do not believe they planned to "crawl" with the diesel engine except in cases where they would have a long horizon?

a "bad compromise" due to the ceiling on the speeds they could achieve with diesels.

Given the Leipzig engine design was laid down just two years after the K-class started production, perhaps the Germans should have waited...

Then why have diesels?

... RANGE !

some things the RM and later KM did simply did not work out as planned. also we have to recall Germany had no overseas bases so enabling overseas operations was a challenge, the diesel engines can be viewed as "insurance" in that respect?