Captured French Fleet in Sealion

[Emperor Palpatine]

Let's just assume it's captured intact and not get bogged down by how it's captured.

The fleet at Mers-el-Kebir comprised 4 battleships and 5 destroyers. Combined with the Kriegmarine's 4 battleships, this gives Germany 8 battleships. The Royal Navy in 1940 has 14 battleships. Italy has 7 battleships and the Royal Navy needs to screen those so in actual fact there are only 7 battleships which can be used against the German invasion and we can't assume they're all in service. At least 2 will be under repair or refit so in actual fact the Royal Navy only has 5 battleships. The same won't apply to Germany since the French fleet would have been recently captured. So now Germany has 8 battleships vs Britain's 5. Those 8 battleships are enough to escort the troop transports crossing the channel and the continual flow of supplies. The Royal Navy won't risk an attack because it's outnumbered. Britain's aircraft carriers are counterbalanced by German air bases on French soil close to the channel.

 

[galveston bay]

most of the French Fleet is in the Med and thus has to get past Gibraltar... so that means a big campaign to take Gibraltar must occur before they can enter the Atlantic

which runs out the clock on 1940 as Fall weather kicks in and prevents any successful operation before the Fall and Winter storms make amphibious operations in the Channel too high risk for the Axis to attempt

which means 1941 is the next possible scheduled date, probably May

and this of course assumes the British don't act as they did historically and neutralize those French warships

 

[sloreck]

Assuming that all of the French fleet in France or North Africa is taken in June 1940, it will take at least a year for the Germans to man them and get used to them. Furthermore things like ammunition and spare parts will be an issue. So, no way any of the French ships get used in 1940, and probably not in 1941 either. BTW each one of the French battleships takes 2500 men at least to man, probably more and where will the Germans come up with that many sailors overnight, of which a certain percentage need to be experienced and technically qualified.

 

[Carl Schwamberger]

I'm wondering where the quqlified crew will come from? Men with five, ten, or twenty years experience in running the French ships? This is not like a few weeks training a tank driver & gunner, or a couple months training the mechanics for a Renault tank. Only in abstract principles are the electrical or steam systems of the ships of Germany like the French of 1940. In practical terms the details of the systems are very different & qualified crew of a German ship cannot step aboard and take a French ship to sea in a few days, weeks, or even months in most cases. Even with highly qualified crew with experience and training it takes five or six months to operate a larger ship like a cruiser at minimal effciency when making a cold start with a new crew. Actually operating it on regular extended cruises & keeping up with the regular maintinace would require far over a year of training for the leaders & techs in the engineering departments

Just being able to read the maintinance logs with any utility will require months. Identifying the correct spare parts for routine maintinance is beyond difficult. Even if elite crews went aboaard before the end of June by 1 September they would still have difficulty taking any smaller simpler craft to sea with any operational utility or even safety.

Second question is where are the crews to come from. Its unlikely all the surplus military and merchant marine crews sitting around in Germany could provide even adaquate ships cadres, let alone full crews. Are the existing German ships to be stripped of crews in a attempt to train them on French ships? Given the probable number of skilled ships crews/cadre & the time to train new basic crew from scratch I'd think it would take a minimum of 24 months to get this fleet ready for its first serious combat training.

Cutting corners on all that would result in serious & routine machinery casualties, and more than a couple catastrophic accidents.

 

[thaddeus]

an attempt at Sealion is way down on list of results.

could see them quickly losing the Richelieu and Jean Bart (not completed and on Atlantic coast)

on the other hand hard to see how British keep Gibraltar and Malta?

 

[alspug]

In the time being discussed the most effective two Battleships in the European theatre have to have been the Nelson class ships . They had the best armour and the best guns . Place both of those against any others with multiple 15 inch armed battleships and battlecruisers in support and their is no chance . At 20,000 yards they can pen roughly 17 inches of German armour so Bismarck and Scharnhorst are toast .

Now before we even think about the French and Germans linking up they nee to get past the 8 9.2 inch guns at Gibraltar . at 30,000 yards your looking around the 5 inch of deck penetration . The Bretagne class had only a 40 mm deck so they are very vulnerable at long range and even at 20,000 yards they will achieve a deck penetration easily . Never mind the fact that the 9.2 was a very powerful gun for it's calibre . By the time they passed Gibraltar never mind the presence of Force H and many destroyers and cruisers they would be badly damaged and in need of a month or two of repairs at the least .

This is like any other thread that assumes Sealion can work , it requires a performance many times better then any historical capability , it requires ASB level interference and lots of British and RN in particular incompetence .

 

[Saphroneth]

There is a real risk here, not in 1940 perhaps but in 1941 - if in a hypothetical the Germans were able to put together Bismarck, Tirpitz, the Twins, the Italian battle line, and the French battle line then they've got enough firepower to put the issue in doubt.

I make it:

Fast Wing

2 Bismarck (8 15" 30 knots)
2 Scharnhorst (9 11" 31 knots)
2 Littorio (9 15" 30 knots)
2 Dunkerque (8 13" 31 knots)
1 Richelieu (8 15" 30 knots)



Medium Wing

2 Andrea Doria (10 12" 26 knots)
2 Conte di Cavour (10 12" 26 knots)


Slow wing
3 Bretagne (10 13.4" or 8 13.4" 20 knots)



As against this the British have:

Fast Wing

Hood (8 15" 31 knots)
2 KGV (10 14" 28 knots)
2 Renown (6 15" 31 knots)


Slow Wing
2 Nelson (9 16" 23 knots)
6 QE (8 15" 23 knots)
4 R (8 15" 21 knots)



This is a battle the British are not guaranteed to win. Note that the RN fast wing is slower than the hypothetical enemy fast wing, and considerably smaller too! (9 v 5)


...of course, this is precisely why the British promptly started sinking every ship in sight that didn't fly one of the British Ensigns - precisely to avoid this potential for defeat, no matter how unlikely it would be in truth.

 

[Archibald]

Cool, there will be a big battleship brawl.

 

[steamboy]

The upgraded Italian 12-inch gunned ships were 26 knotters and had 10 guns. They'd not had 13 guns and 21 knots of speed since the 30's.

Also the 'slow' part of the axis fleet is really outclassed, the French ships had simply not been upgraded in between the war.

The RN would not break its fast ships off to go after the faster axis ones in a battle, they'd stick with the slower ships.

 

[Archibald]

The French and Italian fleets are impressive but that might not be enough. So how about adding the Kaiser High Sea Fleet to the invasion force ?

 

[Saphroneth]

The upgraded Italian 12-inch gunned ships were 26 knotters and had 10 guns. They'd not had 13 guns and 21 knots of speed since the 30's.

Also the 'slow' part of the axis fleet is really outclassed, the French ships had simply not been upgraded in between the war.

The RN would not break its fast ships off to go after the faster axis ones in a battle, they'd stick with the slower ships.

Speed is still very tactically important on the battlefield - it's how Tsushima was decided, for example. The point is that the Axis fleet here has more fast ships compared to slow ships, which means that their battle line has more options tactically (it can control the course of the engagement).

Point taken on the Italian 12" ships, editing.


But the way it comes out is that the Axis fleet has seven new-construction fast dreadnoughts (Bismarck, Littorio, Dunkerque, Richelieu classes) as against two for the British (the KGVs). This forces the British into a situation where who wins matters - and if the Japanese also jump in (this is not necessarily likely, but it's something the British have to consider!) then they're basically caught in an unwinnable vice.


All this does go to show why Mers-el-Kebir actually happened. The British absolutely did not want a situation where there was even the possibility of a battlefleet defeat, so they forced the situation.



(n.b. I've not been counting the British carriers, which would of course be invaluable. I'm just looking at the battle lines to point out that the non-Brits have a genuinely dangerous fleet between them.)

 

[Arkenfolm]

So is the chance of Sealion actually being executed in this scenario still 0% (as in OTL) due to the reasons raised in this thread, or might this boost in naval power give the (extremely foolish) decision the go-ahead (perhaps at Hitler's demand?). Will the Germans actually go ahead in storming English beaches (and predictably getting smacked down into the sea again), or will logic continue to prevail in German High Command?

I guess assuming high success in Gibraltar and Malta?

 

[Lee-Sensei]

Let's just assume it's captured intact and not get bogged down by how it's captured.

The fleet at Mers-el-Kebir comprised 4 battleships and 5 destroyers. Combined with the Kriegmarine's 4 battleships, this gives Germany 8 battleships. The Royal Navy in 1940 has 14 battleships. Italy has 7 battleships and the Royal Navy needs to screen those so in actual fact there are only 7 battleships which can be used against the German invasion and we can't assume they're all in service. At least 2 will be under repair or refit so in actual fact the Royal Navy only has 5 battleships. The same won't apply to Germany since the French fleet would have been recently captured. So now Germany has 8 battleships vs Britain's 5. Those 8 battleships are enough to escort the troop transports crossing the channel and the continual flow of supplies. The Royal Navy won't risk an attack because it's outnumbered. Britain's aircraft carriers are counterbalanced by German air bases on French soil close to the channel.

The French wouldn'tlet the Germans usetheir ships, but if they did... those ships would probably have been used in the Mediterranean.

 

[BELFAST]

I think the Germans could make better use of them to Block the convoys in the atlantic if they can get pass Gibraltar and get crews who can man them.
if they can only use them in the med the taking Malta and protecting the axis supply routes to North africa.

If the Axis can take the suez canal they might be able to get to the indian ocean.

 

[King Augeas]

You can get round the manning problems by having France join the Axis. Implausible, yes, but so's most of this thread.

As for Saph's line-up, well, Hood and the Renowns are horribly vulnerable, but equally the entire Axis slow/medium line is dead meat to 15" shells.

 

[steamboy]

You can get round the manning problems by having France join the Axis. Implausible, yes, but so's most of this thread.

As for Saph's line-up, well, Hood and the Renowns are horribly vulnerable, but equally the entire Axis slow/medium line is dead meat to 15" shells.

And 15-inch rounds would also do a messy thing to the twins or the Dunkirques, as was proven.

 

[King Augeas]

Yes, I'd forgotten that the Dunkerques only had a 9" belt, which was penetrated at Mers El Kebir. Still, the Scharnhorsts are more resilient.

Plus the new Italian battleships are supposed to have had problems with excessive dispersion, also the new French ones too.

 

[steamboy]

Yes, I'd forgotten that the Dunkerques only had a 9" belt, which was penetrated at Mers El Kebir. Still, the Scharnhorsts are more resilient.

Plus the new Italian battleships are supposed to have had problems with excessive dispersion, also the new French ones too.

Very true, the issue with the French quads wasn't solved until post war.

 

[hipper]

Let's just assume it's captured intact and not get bogged down by how it's captured.

The fleet at Mers-el-Kebir comprised 4 battleships and 5 destroyers. Combined with the Kriegmarine's 4 battleships, this gives Germany 8 battleships. The Royal Navy in 1940 has 14 battleships. Italy has 7 battleships and the Royal Navy needs to screen those so in actual fact there are only 7 battleships which can be used against the German invasion and we can't assume they're all in service. At least 2 will be under repair or refit so in actual fact the Royal Navy only has 5 battleships. The same won't apply to Germany since the French fleet would have been recently captured. So now Germany has 8 battleships vs Britain's 5. Those 8 battleships are enough to escort the troop transports crossing the channel and the continual flow of supplies. The Royal Navy won't risk an attack because it's outnumbered. Britain's aircraft carriers are counterbalanced by German air bases on French soil close to the channel.

The German Navy had no operational battleships in July to September 1940

 

[Saphroneth]

The German Navy had no operational battleships in July to September 1940

Hence why I move on to 1941.


My role in doing this set of calculations is not so much to show that it's "possible" (it would be hard for the reasons people have noted) but more WHY the British did things like Mers el Kebir and Taranto.