Could Operation Sealion have worked?

67th Tigers

Banned
Aw! come on P. Your being rather unrealistic in what you are suggesting. The destroyer HMS Jingoist has to break through a weak surface fleet, a concentrated submarine screen, a fighter and bomber screen (don't forget most RN ships of this time had naff all AA), then pass through the minefield(s) to get among the barges where it will be engaged by fast launches and aircraft. In the Dover straights it has no sea room! THEN you want it to sail up and down like the Mersey ferry! Come on. The RN may destroy the German landing fleet but it will take serious losses.


Dover is pretty narrow, but it's under British, not German guns.

The Germans don't have much of a force to challenge the straits.

The Germans have:

3 Light Cruisers (Nurnburg, Koln and Emden) and 2 Destroyers (Z15 and Z5) to challenge to straits and cover the Eastern flank. Scharnhorst and Gneisnau were to be part of this group, but they're repairing after being damaged by the RAF.

(Note, this is dated 16 SEP)

5 Destroyers (Z20, 16, 14, 10 and 6) and 9 Torpedo Boats to cover the Western flank

16 Smaller, older TB and E-Boats to escort the assault ships (including 4 captured Norwegian ships)

21 U-Boats available for war patrols, covering the invasion etc., and the plan mandated more than this:

7 IX and 9 II off Cornwall on the Western Flank
10 VII guarding the start point
8 II in the North Sea
3 II and 2 VII in ambush off Scapa Flow

Challenging these would be:

From the East:
From Scapa Flow: 1 BC, 1 CV, 2 CA, 1 CL and 7 DD
From Rosyth: 2 BB, 1 BC, 3 CLAA, 17 DD, 1 TB and 2 SS
From Blyth: 3 SS
From the Humber: 3 CL and 5 DD
From the Stour (Lowestoft and Harwich): 6 DD, 1 TB, 2 SS and 12 MTB
From the Thames: 2 CL, 18 DD, 1 MTB

In the Straits of Dover: 2 MTB

From the West
From Portsmouth: 1 CL, 14 DD, 5 TB, 2 SS, 6 MTB
From Southampton: 2 DD
From Portland: 2 MTB
From Plymouth: 1 BB, 2 CL, 11 DD, 3 TB
From Milford Haven: 1 TB
From Liverpool: 3 DD
From Firth of Clyde: 1 CL, 10 DD, 9 SS
From Belfast: 3 DD
 
The British would have had hundreds of Spitfires or Hurricanes to do that.

I thought we said the germans would have air superiority...
Wich wasn't that hard to achieve, since the major RAF advantage were the radar stations. Guess what happens if their destroyed VERY early on...

IMO , the battle of Crete is also not a good analogy with a German invasion of Britain. The RN did lose several destroyers or cruisers , but it spent several days to evacuate the troops and didn't have air support.

That's the whole point. Only it won't be less than 1000 aircraft (of wich less than 500 are bombers) taking out ships...

If the Germans had attempted Sealion , the RN would have needed a day or so to destroy the German invasion fleet and it would have been protected by the RAF , so it would have suffered less casualties.

No RAF => big casauties, minefields =>more time...

During Sealion the Germans :
- wouldn't have had air supremacy ( maybe not even air superiority )

Why not ?

- wouldn't have had warships ( but the British would have had a lot )

Say again...

- would have used Rhine barges to transport the troops

Did u pay any attention too what I just wrote ?


- wouldn't have had the element of surprise

I guess God would descend upon the earth and tell Churchill the exact time and place...

- would have managed to land half the forces the Allies managed to land in the first 5 days of the battle for Normandy , if they had been lucky. those men would have had to fight 400,000 British and Commonwealth regulars + the Home Guard.

Assuming they didn't have the element of surprise...
And the british are all in one place
And 1944 is a totally different time. U have less attacking troops, but also less defenders. U also don't have SS Panzer divisions in defence in a terrain ideal for defence. I think their's no other flat place in the world that's easyer to defend than Normandy's Bocage


- would have had big problems in bringing supplies and reinforcements

That's true, but then, the germans had better men, machines, officiers, and tactics



And even if the Germans reach London , street by street fighting in London would make Warsaw , Kiev or Stalingrad look like a walk in the park.

Ever heard of an encirclement ? Because that was just what they planned to do...

If it comes to a prolonged fight , you might find from these figures about production of military equippment that the British would have become stronger than the Germans.

Everyone knows it's not what u have that counts, but how u use it...
But hey, I guess the Panzers were no match for the invincible british armoured forces, as was shown in North Africa, where, if u didn't know, they where more or less humiliated in any but the worst of circumstances
 

Tielhard

Banned
"And even if the Germans reach London , street by street fighting in London would make Warsaw , Kiev or Stalingrad look like a walk in the park."

Would it bollocks.
 

Tielhard

Banned
67 Tigers,

I have some reservations about your British Army obat. I suspect based on the personal experiences of my family on the South Coast at this time that the large numbers of troops you suggest existed were in fact a paper army. It is indeed very hard to imagine they were all well trained or even armed during this period.

Regarding the naval lists you have presented I have a number of questions. It may well be you are right it just does not feel right if you see what I mean.

1) What are the total assets of the kriegsmarine at this time?
2) The list appears to show no pocket battleships available at this time for war is this correct?
3) Only 21 submarines and the number of E-boats is tiny is this really all they could throw into the fray?
4) What is best steaming time for a battleship from Scapa and Rosyth to the Channel or at least the SENS?
5) How would British dispositions be effected if the Italians put to sea during the invasion attempt?
6) How many big guns could the Germans bring to the Pas d'Calais at short notice and how many smaller ones, what percentage of the straights could they cover? Could they duel the British guns?
7) How would the British defeat a minescreen in this situation?
 

67th Tigers

Banned
1. You can prettymuch see (excepting some Minesweepers I missed), this is prettymuch all their servicable craft.

2. Lutzow is being repaired following a Torpedo strike from Apr 40 to Apr 41, Scheer suffered a mechanical breakdown Aug 41 and is U/S for 3 months.

3. Prettymuch, I missed 19 MTB and a dozen minesweepers

4. The main fleet is about 24 hours from the Channel

5. They need to go through the Med and Atlantic Fleets:

The Med Fleet, Forces H and M have between them:

5 BB, 2 BC, 4 CV, 9 CA, 41 DD, 17 SS plus sundry other deployments of Cruisers, MTB etc.

A decisive defeat of the Med Fleet will require the Italians to run Gibraltar (covered by Force H), with Force M behind them.

6. The British have 2 14" naval guns casemated in at Dover (Winnie and Pooh) and 8 6" naval guns, plus field artillery. Who knows what the Germans could bring, railroad arty I suppose, but it's a huge target for the RAF.

7. A lot of the RN DD were minesweeping capable, plus they had minesweepers.
 

Tielhard

Banned
67 Tigers,

Thanks for the prompt reply. I'm off to beddy bo bos in a moment but I think I am going to do some ferreting around on this subject the German naval assets seem less than I remember.

A couple of points anyhow:

4) 24 hours is pretty fast especially keeping an AS screen in place for the capital assets and passing a mine screen.
5) Was not suggesting the Italians break out only that they sally at an important British asset Gib., Malta or Alex. The reason I ask is, I think some of the British assets earmarked as being in home waters are force H assets and down at Gib..
6) I at least am presupposing that the Germand will not attempt Sealion without air superiority at least. So thier guns will be largely OK.
7) Takes time and costs ships.
 
Grimm Reaper of the High Seas to the rescue!

1) Surface fleet includes two elderly pre-dreadnaughts(30+ years old), two pocket battleships(one being repaired following Norway), two battlecruisers(both being repaired following Norway), one heavy cruiser(being re...), 3 light cruisers(one just returning following repairs), 10 destroyers. Also Norway, in which the Germans scraped the sides and bottom of the barrel, involved a total of 20 torpedo boats(E-boats) and 45 submarines.

2) One was available and was mentioned in planning.

3) Including captures and such, perhaps as many as 30 torpedo boats/E boats. Perhaps. Many U-boats were required to return to port following Norway for refitting as it turned out the German torpedos were having some serious difficulty.

4) As the Germans had no battleships of their own it has often puzzled me as to this idea that RN battleships must enter the Channel. Destroyers and cruisers should prove more than sufficient.

5) It likely won't make a difference, unless the Italian fleet goes completely out of character and forces a battle, one in which the British will have some air support and submarines on their side while the Italians won't, perhaps by shelling Malta or Alexandria.

6) In fact a substantial effort was made by the Germans to do just that and the British responded with several convoys past Dover just to show that it was not proving effective. At some point the issue of diminishing returns and an excessively juicy target for the RAF would come up.

7) The size of any minefields available would be limited and most unlikely to stop any determined effort, although surely taking a few ships. Note that the entire German minelaying force consisted of 30 ships under von Ruge, who was also expected to help resupply any invasion force with those same ships(!) so perhaps a few hundred mines in total for the entire width of the English Channel on each side.

Also some RN destroyers and entire squadrons of torpedo boats would have been inside the protective minefields with the invasion fleet!
 
The British would have had hundreds of Spitfires or Hurricanes to do that.

I thought we said the germans would have air superiority...
Wich wasn't that hard to achieve, since the major RAF advantage were the radar stations. Guess what happens if their destroyed VERY early on...

The RAF wouldn't have been anihilated if the radar stations from southern England have been destroyed.
We can assume that the Germans continue to attack the radar stations and manage to destroy the ones in Southern England , thus disrupting the RAF.
In this case , it would be more difficult for the RAF to know when and from where the German bombers are coming.
However , if a major German landing had taken place at Dover , for example , the RAF would have been sent at Dover to protect the RN while it destroys the barges. This could have been achieved without radar.

IMO , the battle of Crete is also not a good analogy with a German invasion of Britain. The RN did lose several destroyers or cruisers , but it spent several days to evacuate the troops and didn't have air support.

That's the whole point. Only it won't be less than 1000 aircraft (of wich less than 500 are bombers) taking out ships...

The RAF would have sent hundreds of fighters to protect the RN. Those fighters wouldn't have had to fight to the finish with the Luftwaffe , just for one day or so , plenty of time for the RN to destroy the barges.

If the Germans had attempted Sealion , the RN would have needed a day or so to destroy the German invasion fleet and it would have been protected by the RAF , so it would have suffered less casualties.

No RAF => big casauties, minefields =>more time...

Why no RAF ?
Considering that the British were producing more planes than the Germans and that the British were able to save some of their trained pilots from the British fighters that were shot down , the anihilation of RAF is not very likely .
As some other members have said , if the Germans had continued to attack radar stations and airfields , the RAF would have withdrawn it's squadrons from the South .
If the Germans had landed after that , the RAF would have sent all its squadrons , not only the southern ones to fight the Germans.
Even if the Luftwaffe had the posibility to do that it would have taken months. During this time , the British would have had more trained men , tanks , fortifications etc.
The Germans mine layers could have been destroyed by the British ships , planes or artillery.

During Sealion the Germans :
- wouldn't have had air supremacy ( maybe not even air superiority )

Why not ?

See above. If things had gotten ugly , the RAF would have withdrawn to the north until the Germans would have invaded.

- wouldn't have had warships ( but the British would have had a lot )

Say again...

The Germans would have had very few warships to support the landings , if any. The British OTOH , would have brought a lot to attack the few German warships and the barges.

- would have used Rhine barges to transport the troops


Did u pay any attention too what I just wrote ?

I fail to see your point here. The Germans were planning to use Rhine barges to transport their troops over the Channel.

- wouldn't have had the element of surprise

I guess God would descend upon the earth and tell Churchill the exact time and place...

Churchill wouldn't had had to be a genius to realize that the Germans wouldn't have landed in Northern Ireland or near Newcastle.
In 1944 , because they had a huge fleet , the Allies could have landed almost anywhere in France. The Germans were expecting them to land near Pas de Calais or Brittany , but not Normandy.
OTOH , since the Germans didn't have seafaring transport ships or warships to protect the barges , it was obvious that they could only cross a narrow portion of the Channel ( and that if the weather was calm ). I think it was pretty obvious they would have landed somwhere between Southampton and Dover , but most likely somwhere on the coast of Kent.

- would have managed to land half the forces the Allies managed to land in the first 5 days of the battle for Normandy , if they had been lucky. those men would have had to fight 400,000 British and Commonwealth regulars + the Home Guard.

Assuming they didn't have the element of surprise...

The Germans , in my oppinion wouldn't have had the element of surprise . The British were expecting to be invaded , and the Germans didn't have many places were they could have landed.

And the british are all in one place

I don't know how many British troops were guarding Scotland at that time.
The British had most of their forces in the South of the country and Britain had a good infrastructure. It probably wouldn't have taken a long time for the British to assemble their forces near the German beacheads.

And 1944 is a totally different time. U have less attacking troops, but also less defenders. U also don't have SS Panzer divisions in defence in a terrain ideal for defence. I think their's no other flat place in the world that's easyer to defend than Normandy's Bocage

I think it's much easier to storm the beaches of Normandy than the cliffs of Southern England. It's also easier to land tanks and guns on the beaches of Normandy from specially designed ships and transport craft than to land tanks and guns near Dover from barges that are usually unloaded by cranes.
The battle of Villers Bocage took place after the landings. It was part of the Allied breakthrough from their beacheads. Those panzer division reacted slow and didn't do much to prevent the Allied landings.

In Normandy , the Allies had a huge fleet and airforce , specialised lading craft , an army that had been trained for almost 3 years for the landing , favourable terrain for landing and the element of surprise , yet they only managed to land 320,000 men and their equippment in the first 5 days.

If the Germans had attempted Sealion in 1940 , they wouldn't have had the advantages the Allies had in Normandy.

How many hours/days/weeks/months do you think those barges would have survived in the Channel ?
How many troops do you think the Germans could have brought to Britain before those barges had been sunk ?
Considering that the Germans had 60,000 dead or wounded in Poland ( which was isolated , was not on an island , didn't have a large and modern airforce and navy , didn't have a powerfull industry , and instead of recieving help , it was attacked by the Soviet Union ) how many of the German soldiers that would had been succesfully landed in Britain would have been killed/captured/wounded ?

- would have had big problems in bringing supplies and reinforcements

That's true, but then, the germans had better men, machines, officiers, and tactics

They had few Panzer IV in 1940 and I don't know how many tanks or machines they would have been able to land. It's true they had good officers and tactics , but those officers and their men would have had to fight using light armament mostly and few supplies against a much larger and determined force on its' own turf.


And even if the Germans reach London , street by street fighting in London would make Warsaw , Kiev or Stalingrad look like a walk in the park.


Ever heard of an encirclement ? Because that was just what they planned to do...

How many men do you think they would have needed to encircle London ?
I seriously doubt they would have been able to land enough men and heavy weaponry to do that.

If it comes to a prolonged fight , you might find from these figures about production of military equippment that the British would have become stronger than the Germans.

Everyone knows it's not what u have that counts, but how u use it...
But hey, I guess the Panzers were no match for the invincible british armoured forces, as was shown in North Africa, where, if u didn't know, they where more or less humiliated in any but the worst of circumstances

Well , during WWII , the Germans had very good stuff and new how to use it but they lost . The Allies just had more of everything.
 
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Just as a matter of interest - I have a copy of the novel of 1974 Sandhurst Wargame and one thing the Germans would have been ok on was the weather. From the period 19th September to 28th September the sea state never exceeded 4 (this is the maximum sea state that the inland barge could handle safely). Furthermore, most of October was fairly calm with the final break of weather not happening until the very end. In particular the 2 week period from 11th october was also very calm with gentle easterly breezes.

To be honest, that is about the only piece of luck running in the Germans' favour.

I also have two points regarding fortifications - earlier Backstab mentioned Eban Emal - the Parachute Engineers reheasred that for many months. Against the UK, the German airborne forces had to re-organise following Holland where losses were quite high and they almost certainly didn't have the detailed knowledge that they had of Eban Emal.

Conversely, Britsh fortifications were often at the level of a joke. Some were impressive - those at Cucksmerehaven for instance - this is one of the prime landing sites. Some of those built for the GHQ line, however... Dotted around the south east are plenty of brick based pillboxes stuck out in the middle of fields- frankly they were deathtraps.
 
For general edification: the forces the RN has available in the Channel during the period:

According to the Oxford History of the Royal Navy 'by early September 1940, Admiral Sir Reginald Plunkett-Ernle-Erle-Drax's [yes, that is the man's full name] Nore Command had 38 destroyers and 7 'Kingfisher/'Shearwater' - class coastal escorts based at Immingham, Harwich and Sheerness...these were backed up by the cruisers Manchester, Birmingham and Southampton at Immingham, and Galatea and Aurora at Sheerness. On the other flank of the invasion, Commander-in-Chief, Portsmouth deployed another nine destroyers and five Free-French torpedo boats backed up by the old cruiser Cardiff and battleship Revenge. Now fewer than 700 smaller craft were also deployed, with 200-300 at sea at all times from the Wash to Sussex to provide early warning.' (p 354)

That's excluding what's with the Home Fleet or is in the escort forces in the Western Approaches. The simple fact is, the RN would absolutely dominate the Channel.
 

MacCaulay

Banned
Okay...let's try a different approach...a British-based POD.

In the dark days of the Battle of France, Hugh Dowding is down with a severe chest cold (act of God, he got it in a sudden POD rainstorm), and the Spitfires that he was successfully keeping in reserve across the Channel are given the go ahead and sent into the battle. After brave fighting, the British manage to get about half their forces out of Dunkirk, despite the fact that no 'stop' order is issued. The panzers just keep rolling, with less aircover now that the Spitfires have taken a bite out of the Stukas.

Half the Spitfires and Hurricanes that went across the Channel don't come back. Fighter Command has less fighters than it left with, and Eagle Day is coming. Goering is confidant, and even Jodl begins to think that this might work. As the tanks line up on the shore of Normandy, preparing to cross, Guderian and his new protege, Rommel, stare across the Channel, waiting for air cover, clement weather, and boats.

Thoughts? (Just to be clear, I'm not totally sold on this one either, but I don't think it was a POD that was put forward recently)
 
Okay...let's try a different approach...a British-based POD.

In the dark days of the Battle of France, Hugh Dowding is down with a severe chest cold (act of God, he got it in a sudden POD rainstorm), and the Spitfires that he was successfully keeping in reserve across the Channel are given the go ahead and sent into the battle. After brave fighting, the British manage to get about half their forces out of Dunkirk, despite the fact that no 'stop' order is issued. The panzers just keep rolling, with less aircover now that the Spitfires have taken a bite out of the Stukas.

Half the Spitfires and Hurricanes that went across the Channel don't come back. Fighter Command has less fighters than it left with, and Eagle Day is coming. Goering is confidant, and even Jodl begins to think that this might work. As the tanks line up on the shore of Normandy, preparing to cross, Guderian and his new protege, Rommel, stare across the Channel, waiting for air cover, clement weather, and boats.
Damages the RAF and reduces the size of the army but does nothing against the RN. Hence the Jerries still end up stuck mid-channel surrounded by Destroyers and MTBs.
 
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Some thoughts...

Okay...let's try a different approach...a British-based POD.

In the dark days of the Battle of France, Hugh Dowding is down with a severe chest cold (act of God, he got it in a sudden POD rainstorm), and the Spitfires that he was successfully keeping in reserve across the Channel are given the go ahead and sent into the battle. After brave fighting, the British manage to get about half their forces out of Dunkirk, despite the fact that no 'stop' order is issued. The panzers just keep rolling, with less aircover now that the Spitfires have taken a bite out of the Stukas.

Half the Spitfires and Hurricanes that went across the Channel don't come back. Fighter Command has less fighters than it left with, and Eagle Day is coming. Goering is confidant, and even Jodl begins to think that this might work. As the tanks line up on the shore of Normandy, preparing to cross, Guderian and his new protege, Rommel, stare across the Channel, waiting for air cover, clement weather, and boats.

Thoughts? (Just to be clear, I'm not totally sold on this one either, but I don't think it was a POD that was put forward recently)

I'm not sure that Sealion would have succeded even if the Germans had had air superiority over Southern Britain.
The chances of succes also depend on how fast the Germans finish the conquest of France. How many tanks and planes do you think they would have lost at Dunkirk if the fighters had been sent to France and the tanks had kept rolling ?
If the Germans had suffered that kind of losses , would they have been delayed in the conquest of France ?

If the battle for the rest of France would had taken more than a month , I think that the British would have had time to replenish their losses.
 

backstab

Banned
One other factor to add would be WI Dunkirk was a failure.... this would deny the English a lot of experianced soldiers.
IMHO:
A sucessful Sea Loin would have :
1] Germany stating their industry on a war footing in 1938
2] Destroying the Dunkirk evacuation
3] Air Superiority
4] A way of keeping the RN from the Channel
5] Decent landing craft
 
So...

So, backstab, now that you've pretty well outlined the necesities for a succesful Sealion, how do you imagine they might have been achieved? Could they have been achieved?
 

MrP

Banned
So, backstab, now that you've pretty well outlined the necesities for a succesful Sealion, how do you imagine they might have been achieved? Could they have been achieved?

Something this thread's been making me think about lately is the possibility of dumping the U-boat prog.

  1. They aren't much use in the Channel because of lack of sea room.
  2. There's no point splitting Germany's resources trying to starve the UK while also invading. One or the other, please.
  3. The elimination of this construction frees up slips for troop transports that are far superior to Rhine barges.

The problem with building proper troop transports is that the British will almost certainly find out and strengthen their coastal defences - and probably the regular army, too - in anticipation of an invasion. So a disastrous Dunkirk in such an ATL wouldn't be as much of a blow as in OTL.

EDIT: Of course, there's always the option of going the other way, eliminating ALL Kriegsmarine capship production and sinking everything that tries to enter British harbours.
 

backstab

Banned
So, backstab, now that you've pretty well outlined the necesities for a succesful Sealion, how do you imagine they might have been achieved? Could they have been achieved?
No I do not beleive that they would have been acheived....

1] War footing- Germany expecting Czec's to fight so he orders Speer to increase production ???
2] Dunkirk - Put Georing back on his leash..... let the army deal with the evacuation point instead of the LW
3] Air Superiority - again I beleive that Goering/Hitler had too much input. Let the LW plan and exicute
4] I'm not a Navy person so I would not have a clue...
5] This would require planning at least 12 months prior to the invasion. Design blue water landing craft and build them. The Germans had some but they wernt avail until '41. Maybe if they were put in production in early 39 ????

mfp.gif

The Naval Landing Crafts - called "Marinefährprahm" in German were the largest landing craft used by the Kriegsmarine. Although required for Operation Sealion (Invasion of England) in 1940, the first of this transport ships were delivered in 1941. The development of this ship went through several Types (A-D), whose size and armament grew from class to class.
They were mainly used for transport and supply duties and not for their initial invasion role and could transport 200 Soldiers or 140ts of equipment, including Tiger tanks.
Marinefährprahme were used in almost all Kriegsmarine operational areas, the British Channel, the Mediterranean and the Black Sea.

mfp.gif
 

MrP

Banned
4] A way of keeping the RN from the Channel

Well, your aim is to ensure that either the RN dare not enter the Channel or that it cannot.

I don't believe that it's possible to stop the OTL RN from entering the Channel if they believe that Sealion is serious. The government will know that destroying the invasion fleet and severing its supply lines are matters of the utmost import. If the Army is defeated by the Germans, then the existence of the RN is useless.

So one must make it impractical for the RN to enter the Channel. That's really tricky. Really really tricky. I'll have to get back to you. Need to do some writing atm.

Some initial thoughts:
  • Airpower won't do it alone; you do need some small warships, too.
  • Perhaps no Norway means fewer german casualties, so more vessels available for Sealion.
 

backstab

Banned
Well, your aim is to ensure that either the RN dare not enter the Channel or that it cannot.

I don't believe that it's possible to stop the OTL RN from entering the Channel if they believe that Sealion is serious. The government will know that destroying the invasion fleet and severing its supply lines are matters of the utmost import. If the Army is defeated by the Germans, then the existence of the RN is useless.

So one must make it impractical for the RN to enter the Channel. That's really tricky. Really really tricky. I'll have to get back to you. Need to do some writing atm.

Some initial thoughts:
  • Airpower won't do it alone; you do need some small warships, too.
  • Perhaps no Norway means fewer german casualties, so more vessels available for Sealion.

What about Sea Mines at each end of the channel ? I think some one mentioned this before
 
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