Sealion naval battles

[BlairWitch749]

Just looking to get some thoughts from the boards naval experts on potential sea battles surrounding sealion for the purposes of Der Manstein Kommt 2.0

The composition of the German battlefleet will be approximately Bismarck and Tirpitz battle wagons (completed ahead of schedule via POD's) Scharnhorst and Gneisenau Battle cruisers, Scheer and Deutchland pocket battle ships, 5 Hipper class cruisers (Lutzow and Seydlitz completed and Blucher not sunk in Norway) 4 light cruisers koln leipzig nurnberg and emden, and about 12ish destroyers

The question is how much of the home fleet/RN would be required for parity with this force and how much of the home fleet/RN would be required for clear, but not obscene superiority against this force

For the sake of simplicity, please leave aircraft carriers outside the discussion and focus on gun combatants only

 

[CultBoy]

Just for an roughly equal fight you need from the Royal Navy

4-5 Battleships/Battlecruisers
12-14 Cruisers
12-16 Destroyers

Now the Home Fleet always kept three/five capital ships at Scapa Flow in case of a major sortie with destroyers and cruisers either with them or manning patrol lines. So with my limited knowledge of deployment patterns its takes the RN 3 to 4 days to organise a force that has near parity, a week or so to get a overwhelming force. Excluding Aircraft carriers and the Royal Navy coastal forces (MTBs ect) because I dont know the deployment patterns.

The capital ships in such a force would probably be Nelson or Rodney or both, some old R Class battleships, one or more of the battlecruisers and maybe a KGV class battleship. As for cruisers and destroyers dont know enough to be certain.

 

[Astrodragon]

Just looking to get some thoughts from the boards naval experts on potential sea battles surrounding sealion for the purposes of Der Manstein Kommt 2.0

The composition of the German battlefleet will be approximately Bismarck and Tirpitz battle wagons (completed ahead of schedule via POD's) Scharnhorst and Gneisenau Battle cruisers, Scheer and Deutchland pocket battle ships, 5 Hipper class cruisers (Lutzow and Seydlitz completed and Blucher not sunk in Norway) 4 light cruisers koln leipzig nurnberg and emden, and about 12ish destroyers

The question is how much of the home fleet/RN would be required for parity with this force and how much of the home fleet/RN would be required for clear, but not obscene superiority against this force

For the sake of simplicity, please leave aircraft carriers outside the discussion and focus on gun combatants only

Chance of T & B being completed early enough for mid-1940 requires an ASB about the size of a 747.
You simply cant shave a year off a BB building time, and Tirptiz requires more like 2 years.
IIRC, they couldnt be started earlier due to the unavailability of the building slips. And it doesnt matter how many concrete bumkers you aren't building (although you seem to have a few tons of concrete replaced by just about anything and everything else in the German arsenal), the restrictions on heavy ship building are due to constraints on the supply of the large precision engineerng bits which simply arent available from anywhere other than the OTL producers.
Why do you think the British, who had a far bigger shipbuilding industry, and needed new BB's desperately, couldnt complete them faster?

B&T in SeaLion is handwavium of the first order.

As to the rest of the fleet. As it was, the KM was LUCKY to only have the losses it did in Norway. Requiring basically the whole fleet available means no Norway, anything else again is sheer ASB-ness.
And even if it was - well, the RN capital ship gunnery officers thank you for the xtra targets. The KM simply isnt big enough to go head to head against the RN in its home waters, and no amount of POD's is likely to change that.

 

[BlairWitch749]

Chance of T & B being completed early enough for mid-1940 requires an ASB about the size of a 747.
You simply cant shave a year off a BB building time, and Tirptiz requires more like 2 years.
IIRC, they couldnt be started earlier due to the unavailability of the building slips. And it doesnt matter how many concrete bumkers you aren't building (although you seem to have a few tons of concrete replaced by just about anything and everything else in the German arsenal), the restrictions on heavy ship building are due to constraints on the supply of the large precision engineerng bits which simply arent available from anywhere other than the OTL producers.
Why do you think the British, who had a far bigger shipbuilding industry, and needed new BB's desperately, couldnt complete them faster?

B&T in SeaLion is handwavium of the first order.

As to the rest of the fleet. As it was, the KM was LUCKY to only have the losses it did in Norway. Requiring basically the whole fleet available means no Norway, anything else again is sheer ASB-ness.
And even if it was - well, the RN capital ship gunnery officers thank you for the xtra targets. The KM simply isnt big enough to go head to head against the RN in its home waters, and no amount of POD's is likely to change that.

shaving several months off B and T isn't totally ASB with POD's going back to 1936 and 37. I was allowing for the same Norway losses as OTL minus Blucher (with all the destroyers and other cruisers destroyed as OTL)

lets leave that debate on the side for a moment, how big of a force do you think is required for parity? and how big for clear, but not overkill superiority

 

[Astrodragon]

shaving several months off B and T isn't totally ASB with POD's going back to 1936 and 37. I was allowing for the same Norway losses as OTL minus Blucher (with all the destroyers and other cruisers destroyed as OTL)

lets leave that debate on the side for a moment, how big of a force do you think is required for parity? and how big for clear, but not overkill superiority

You arent shaving a few months, you are shaving 12-18. That simply isnt possible. And in 1936 Hitler wasnt planning on war as early as 1939, so there is no need to spend a lot of money trying to speed up BB production. So what excuse is there to try and speed things up?

The force required for parity is considerably bigger than the entire KM pre-Norway. And thats assuming the RN doesnt reinforce from convoys and the Med.

 

[Grimm Reaper]

Astrodragon, Churchill rightfully blasted the Anglo-German naval agreement granting Germany a surface fleet 35% that of the British on the grounds that building up to those so-called limitations would require that Germany build every last warship it could, as fast as it could, without respite or rest or consideration of finances for the next ten years.

Needless to say that's hardly limiting but it also shows that the German naval construction capacity was not up to the job of building a fleet comparable to the RN, even before the inevitable British naval response.


During the time of August-September 1940 the British had no less than nine capital ships available in home waters and several times as many cruisers as the Kriegsmarine had destroyers even before Germany lost half those destroyers in Norway.

Germany had the twins, one damaged in Norway and both undergunned, two pocket battleships(heavy cruisers with delusions of grandeur) and nothing else resembling a capital ship.

 

[BlairWitch749]

You arent shaving a few months, you are shaving 12-18. That simply isnt possible. And in 1936 Hitler wasnt planning on war as early as 1939, so there is no need to spend a lot of money trying to speed up BB production. So what excuse is there to try and speed things up?

The force required for parity is considerably bigger than the entire KM pre-Norway. And thats assuming the RN doesnt reinforce from convoys and the Med.

I don't see how its 12 to 18 when B was ready for a combat sortie 6 months later... honestly the Germans where pretty leisurely with their ship construction; partially because they didn't think there would be war till 42 AND because there was enormous demand for materials and workers in various other military and civilian projects

With the cancellation of the Oder line and the KM getting a cut of the action, I decided their share would be too small to do much more new construction BUT would be suffecient for them to be more aggressive in completing their open projects (adding shifts and the like?)

I think you read my question backwards... I wasn't asking if they could have parity with the RN overall which is ASB; I was asking how much of the RN would be required to be in attendance to have parity with a KM battlegroup of that size and how much of the RN would be required to be concentrated to have a superior but not ultra superior force

 

[Astrodragon]

I don't see how its 12 to 18 when B was ready for a combat sortie 6 months later... honestly the Germans where pretty leisurely with their ship construction; partially because they didn't think there would be war till 42 AND because there was enormous demand for materials and workers in various other military and civilian projects

With the cancellation of the Oder line and the KM getting a cut of the action, I decided their share would be too small to do much more new construction BUT would be suffecient for them to be more aggressive in completing their open projects (adding shifts and the like?)

I think you read my question backwards... I wasn't asking if they could have parity with the RN overall which is ASB; I was asking how much of the RN would be required to be in attendance to have parity with a KM battlegroup of that size and how much of the RN would be required to be concentrated to have a superior but not ultra superior force

Speeding up a BB is not nearly as simple a matter as just tossing more men at it.
The people and equipment you need are HIGHLY specialised, and noone (not even the USA) could just pull them out of a hat. It takes years just to build the facilities.
Bismarks first cruise was in May 1941. So thats 9 months early. And even then not all of her equipment was ready. Tirpitz was considerably later.

And there is a much worse problem for the KM than just the availability of the ships. That is the availability of trained manpower. Which they didnt have enough of for SeaLion WITHOUT the B&T (theres about 5,000 men right there), and the virtual destruction of the surface fleet (which freed up some more men). They simply dont have the manpower to do this.

 

[Grimm Reaper]

Astrodragon, and the Kriegsmarine required shakedown cruises and operations lasting several months after the ship went to sea but before it was actually considered combat worthy.

There is absolutely no possibility of the KM tossing decades of regulations proven sensible so they can throw a single untrained ship into a battle.

 

[Mackem89]

I remember reading a Royal Navy OrBat as of September 16th 1940 on a forum a while back. IIRC, the Home Fleet consisted of HMS Nelson, HMS Rodney, HMS Hood and HMS Repulse, all stationed at Scapa Flow and Rosyth, and HMS Revenge stationed in the Channel at Plymouth. HMS Queen Elizabeth was also in Home Waters but it was undergoing refit and repair.

You also had HMS Renown based in Gibraltar as part of Force H, and HMS Barham and HMS Resolution were in port at Freetown preparing for the Dakar Landings. These could probably have been called back to British waters if the need arose.

Altogether though, the Royal Navy, plus ships from the Free French, Dutch, Polish, Norwegian, Canadian and Austrlian Navies, added up to about 250 ships in British and Atlantic Waters. I'm not sure about the German numbers, but you must be getting towards them being outnumbered 10:1.

No Contest

 

[Gridley]

And let's not forget that if the Bismark and Tirpitz were in commission the RN might very well have held more of its forces in home waters. Quite a lot of the fleet was in the Med, IO, or Far East.

FYI, you can find a complete OrBat for the RN on Sept. 7th, 1940 here:

http://niehorster.orbat.com/017_britain/40-09-10_Sealion/Navy/home-fleet.html

It shows what ships were part of Home Fleet, and where they were as well as any adverse notes about their condition.

And for comparison on September 3rd, 1939 here:

http://niehorster.orbat.com/017_britain/39_navy/_navy.html

 

[Da Pwnzlord]

I think if we want to see ASB Sealion naval battles, the timeline should include the British fumbling and loosing Suez, Spain entering and taking Gibraltar, and the Regia Marina sortieing into the English Channel.

 

[Gridley]

I think if we want to see ASB Sealion naval battles, the timeline should include the British fumbling and loosing Suez, Spain entering and taking Gibraltar, and the Regia Marina sortieing into the English Channel.

Aw, let's not stop there! With the Suez and Gib in Axis hands, the IJN sails across the IO, refuels, and sails up to the English Channel!

"September 7th, 1940, a day which will live in Infamy..."

Between the IJN, the RM, and the KM, I think we actually have enough naval power to hold back the RN.

 

[Da Pwnzlord]

Now THAT'S how to write a timeline! Shall Stalin declare war on Britian for the lulz and FDR randomly cut off Lend-Lease as well?

 

[Gridley]

Now THAT'S how to write a timeline! Shall Stalin declare war on Britian for the lulz and FDR randomly cut off Lend-Lease as well?

Ooh! The Soviet Baltic Fleet could join the invasion fleet!

"Signal to Home Fleet: have sighted hostile force including BB Bismark, Oktyabrskaya Revoluciya, Conte Di Cavour, Nagato, off Portsmouth. Engaging, God Save the Queen."

 

[Astrodragon]

Ooh! The Soviet Baltic Fleet could join the invasion fleet!

"Signal to Home Fleet: have sighted hostile force including BB Bismark, Oktyabrskaya Revoluciya, Conte Di Cavour, Nagato, off Portsmouth. Engaging, God Save the Queen."

King, Gridley, King...

 

[BlairWitch749]

Ooh! The Soviet Baltic Fleet could join the invasion fleet!

"Signal to Home Fleet: have sighted hostile force including BB Bismark, Oktyabrskaya Revoluciya, Conte Di Cavour, Nagato, off Portsmouth. Engaging, God Save the Queen."

You forgot the confederate navy with flagship USS Chuck Norris

 

[Astrodragon]

One teeny little issue...

Since the German plan had 2 minefields sealing off the invasion lanes, exactly WHERE is the KM going to engage the Home Fleet?

I cant see them doing it from the Biscay side as they'd have to sail all around the UK first, plus get all the supplies in place.

If they do it from the North Sea, they are pretty much out of Stuka and Me109 range....oops....

And of course, even when they are under air cover, the RN has subs too. Which pre-war used the channel as an excercise area. NEVER fight a battle in your opponents excercise area, its a disaster waiting to happen...

 

[MikeTurcotte]

Ooh! The Soviet Baltic Fleet could join the invasion fleet!

"Signal to Home Fleet: have sighted hostile force including BB Bismark, Oktyabrskaya Revoluciya, Conte Di Cavour, Nagato, off Portsmouth. Engaging, God Save the Queen."

Yeah...but which one of these Axis BBs is towing the Oktyabrskaya Revoluciya? I do not believe that ship was capable of operating independently in the open ocean in 1940.

Mike Turcotte

 

[galveston bay]

And let's not forget that if the Bismark and Tirpitz were in commission the RN might very well have held more of its forces in home waters. Quite a lot of the fleet was in the Med, IO, or Far East.

FYI, you can find a complete OrBat for the RN on Sept. 7th, 1940 here:

http://niehorster.orbat.com/017_britain/40-09-10_Sealion/Navy/home-fleet.html

It shows what ships were part of Home Fleet, and where they were as well as any adverse notes about their condition.

And for comparison on September 3rd, 1939 here:

http://niehorster.orbat.com/017_britain/39_navy/_navy.html

I used to have that site as a favorite but lost in a computer crash, thanks for reposting

short of huge departures from history, the Germans have no chance of executing Sea Lion or building up a sufficiently large surface fleet to have a chance against the RN or achieving air supremacy over British home waters. Air superiority.. maybe, but not air supremacy and they would have to have that. Sorry Blairwitch, it just isn't a likely scenario.

If you want a good German vs RN naval battle, then something involving Norway 1941-43 is a better bet