WI/Plausibility Check: Sealion goes ahead and fails?

And what of the 6,800 mines the Germans would have sewn to protect the invasion route ... or the fleet of 10 destroyers, 20 torpedo boats, 40 motor torpedo boats, 90 or so patrol boats, 100's of mine sweepers / layers, 27 U-Boats ... or the 6 batteries of super heavy naval guns (30 guns in total of 170mm to 380mm), the 42 heavy and medium batteries (probably of limited use but still ready to fire when needed) ... or the torpedo and dive bombers of the Luftwaffe?

6800 mines is something on the order of 3-4 mines per mile of invasion route - the invasion plan had landings spread all over southern England. Even if they picked one end of the channel and mined it "heavily" 6800 mines is on the order of 500 mines per mile of channel spread over any depth of mine field it is a risk but not huge. That's a minor nuisance not a minefield that would keep the British out.

10 destroyers, 20 torpedo boats, 40 motor torpedo boats, 90 patrol boats, 100's of mine sweepers/layers and 27 u-boats. Okay, first 100's of mine sweepers? What is your source on this? The Germans had fishing boats that they called mine sweepers, but dedicated mine sweepers? I am skeptical of this. What is the difference between torpedo boats and motor torpedo boats? I think you are double counting here. Maybe they had 60 E-Boats maybe. 90 Patrol boats - if they count fishing boats that make patrols maybe.

Take this against what the British are documented to have in the channel at the time targeted for the invasion. 79 Destroyers assigned to the Channel, 8 Cruisers, 68 mine sweepers (actually designed to be mine sweepers), in addition "many corvettes" which are larger than MTB's but smaller the Destroyers, 1 Aircraft Carrier, 2 Battleships, 1 Battle Cruiser escorted by 3 anti-aircraft Cruisers and a Destroyer flotilla.

The above is just what is actually in and around the channel, the rest of the home fleet is within 12-16 hours of arriving. And that included 5 more Battleships, 3 more Cruisers, and 9 more destroyers.

There were also 25 submarines but they would be unlikely to be used.

Don't forget the RAF, they have the unengaged wings from the north of England that were planned to be pulled into battle when the invasion was sighted. So the Luftwaffe would be outnumbered and fighting fresh defenders.

As for the torpedo and dive bombers that you refer to above, bombing warships is much different than bombing merchant ships, which was the experience that the German pilots have to this point in the war. The British would loose some ships but the RN is fighting off an invasion they would be willing to expand ships to win.
 
As for the torpedo and dive bombers that you refer to above, bombing warships is much different than bombing merchant ships, which was the experience that the German pilots have to this point in the war. The British would loose some ships but the RN is fighting off an invasion they would be willing to expand ships to win.
I'll get back to you on the rest as the figures you gave for the RN do not stack up with my research so I'll have to go back and check my sources.

But the Luftwaffe have plenty of experience of combat with RN ships ...

On 9th April 1940 2 battle groups of the Home Fleet were attacked by 41 Heinkel He 111’s and 47 Junkers Ju 88’s over a period of 7 hours. During this time only 4 planes were lost whilst 1 destroyer was sunk and 5 cruisers and a battleship were damaged. This may not seem like much damage but the Home Fleet was forced to retire to safer waters due to a shortage of AA ammunition and lack of air cover. They were fortunate that they retired when they did as the Stuka’s were already en-route with pilots used to hitting much smaller moving targets and without adequate AA and fighter cover many more ships could have been lost or damaged.

In July 1940 alone they sank HMS Brazen on convoy duty, HMS Wren on minesweeper escort duty, HMS Cordington in Dover Harbour, HMS Delight in the Channel, and HMS Foyle Bank in Portland Harbour.
 
6800 mines is something on the order of 3-4 mines per mile of invasion route - the invasion plan had landings spread all over southern England. Even if they picked one end of the channel and mined it "heavily" 6800 mines is on the order of 500 mines per mile of channel spread over any depth of mine field it is a risk but not huge. That's a minor nuisance not a minefield that would keep the British out.

10 destroyers, 20 torpedo boats, 40 motor torpedo boats, 90 patrol boats, 100's of mine sweepers/layers and 27 u-boats. Okay, first 100's of mine sweepers? What is your source on this? The Germans had fishing boats that they called mine sweepers, but dedicated mine sweepers? I am skeptical of this. What is the difference between torpedo boats and motor torpedo boats? I think you are double counting here. Maybe they had 60 E-Boats maybe. 90 Patrol boats - if they count fishing boats that make patrols maybe.
The mines were new mines laid out to be augmented by the mines already laid by the British, French and Germans prior to the invasion. The plan was to clear lanes for the invasion fleet through the existing mine fields then plug up the "safe" routes that the RN used with the new mines. This would hamper any rapid movement of ships and keep them away from the invasion fleet.

The torpedo boats refered to are the equivalent of small destroyers in the RN but specifically based around torpedo armament. The smaller motor torpedo boats are the S-boats and the patrol boats primarily E-boats. I can't say what the minesweepers / minelayers are, maybe some are fishing boats but they would still be armed and used to cause confusion if nothing else. All of this information is based on German documentation captured by the admiralty and published as one document by the Director of Naval Intelligence in 1947.
 
Take this against what the British are documented to have in the channel at the time targeted for the invasion. 79 Destroyers assigned to the Channel, 8 Cruisers, 68 mine sweepers (actually designed to be mine sweepers), in addition "many corvettes" which are larger than MTB's but smaller the Destroyers, 1 Aircraft Carrier, 2 Battleships, 1 Battle Cruiser escorted by 3 anti-aircraft Cruisers and a Destroyer flotilla.

The above is just what is actually in and around the channel, the rest of the home fleet is within 12-16 hours of arriving. And that included 5 more Battleships, 3 more Cruisers, and 9 more destroyers.
This will take some time to do as I have to trawl back through the records at naval-history.net to double check my figures. So far I have the one Aircraft Carrier based at Scapa Flow, HMS Furious, no mention of any movements to the channel though as it was used extensively to patrol the Norwegian coastal waters. Will look at the rest when I get a chance.
 
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The Luftwaffe had the He 115 torpedo bomber, but the main form of attack would have been form the Ju 87 and Ju 88 dive bombers. As for Radar only the largest of RN warships had any kind of surface Radar used for direction and target control, the smaller vessels had basic sets for detecting aircraft at this stage of the war. However I've not found anything in my research of the subject that talks of infrared being used by either side. Not to say the information isn't there its just that I obviously haven't looked hard enough :)

No Lw did not have the He 115 torpedo bomber - it's a Twin-float Seaplane, and as such comes under the control of Raeder not Goering. My comment on radar & I/R refered to in means the Lw would need to attack the RN at night - the 'they' refered to the Germans not the RN.
 
No Lw did not have the He 115 torpedo bomber - it's a Twin-float Seaplane, and as such comes under the control of Raeder not Goering.
The He 115 was operated by both the arms, the luftwaffe had 24 of them stationed in Norway. They were specifically designed as a torpedo bomber but could be used as a mine layer as well.
 
The mines were new mines laid out to be augmented by the mines already laid by the British, French and Germans prior to the invasion. The plan was to clear lanes for the invasion fleet through the existing mine fields then plug up the "safe" routes that the RN used with the new mines. This would hamper any rapid movement of ships and keep them away from the invasion fleet.

The torpedo boats refered to are the equivalent of small destroyers in the RN but specifically based around torpedo armament. The smaller motor torpedo boats are the S-boats and the patrol boats primarily E-boats. I can't say what the minesweepers / minelayers are, maybe some are fishing boats but they would still be armed and used to cause confusion if nothing else. All of this information is based on German documentation captured by the admiralty and published as one document by the Director of Naval Intelligence in 1947.

Okay I did another search and could come up with a total of 11 destroyer class ship and 9 Torpedo boat class ships that the German Navy had in stock in the summer of 1940 (Before France but after Norway) There were another 1 Destroyer and 8 Torpedo boats coming online before September (maybe 4 more Ex-Norwegian). http://www.naval-history.net/XDKWW2-4006-17German.htm. They don't have records for MTB class boats or mine sweepers but I would be very surprised to see numbers as high as you are saying.

As for the Mines yes that would be their best bet but that's a fairly risky operation for the Barges that have to come back to Europe to reload for resupply. Which as I pointed out is their largest problem. Even if they got the troops there in the first place they were counting on the same set of barges and tow boats to be used to resupply. So they are going to be clearing and re-mining those same safe lanes every time the barges go past? Through tide changes? When the Mines break loose? That's asking to loose barges. The British Navy's goal if the first wave gets landed is to kill those barges (or tow boats), re-mining the lanes makes their job easier.

Second, confusion is the enemy of a landing operation. Having "hundreds" of half trained semi-armed minesweepers running around shooting at anything that moves is asking for "black on black" kills. The odds of them actually sinking a RN Destroyer or Cruiser is low if they hit them, however the odds of them sinking a barge if they hit them is high. The last thing the German's want is anyone shooting - remember the plan was for a night crossing this was supposed to be a quiet operation. Not that it would work, but that was the plan. :rolleyes:
 

BlondieBC

Banned
It seems consensus that Operation Sealion would have failed if it went forward, but could Operation Sealion have gotten to the stage where the soldiers were on the boats and heading across the channel to their deaths?
I am not that much into 20th century history so I'm interested to learn a little more about the second world war.

Sure and they can keep a beachhead for a few days, maybe a few weeks. Problem is that RN will throw in enough assets to cut the supply line. The best realistic scenario for the German is to trade regiments for ships. Probably the optimal SeaLion would just be a fake operation to try to draw RN into English channel for a fight after you win air superiority. Send out mostly empty ships as bait and hope the RN comes and fights, and the loss ratios are good for the Germans.

IMO, Germany could have defeated the UK if one believes the Soviet Union will not enter the war until it is clear Germany is losing. But it would take years and require what is often called the Med Strategy, but really involves a lot more and likely taking of big chunks of Africa. And a massive naval and naval aviation building program.
 
The Luftwaffe had the He 115 torpedo bomber, but the main form of attack would have been form the Ju 87 and Ju 88 dive bombers.
Total production of the former? 138 including exports and production after the plausible window for Seelowe

As for the latter, yes they are something of a threat. But look at their level of success off Dunkirk... 7% of the British DDs sunk by air attack, yet the RN continued the evacuation? Or Crete... Even given another 9 months to properly work up antishipping capability they inflicted 18% losses amoungst Cruisers and Destroyers, and that was when the RN was operating at such range from base they had no hope of any air support and little hope of restocking AA ammo without returning to Alexandria.
 
IMO, Germany could have defeated the UK if one believes the Soviet Union will not enter the war until it is clear Germany is losing. But it would take years and require what is often called the Med Strategy, but really involves a lot more and likely taking of big chunks of Africa. And a massive naval and naval aviation building program.

Which will also require the United States to stay neutral. Once they're in the fight, Germany is doomed.
 
Now we all know that at Toranto it only took 24 aged stringbags to do a considerable amount of damage

Yeah, but those people were trained only and entirely in exactly that sort of operation and the planes were, while obsolete, perfect for the torpedo attacks.

Germans trained their pilots for CAS and tactical bombing of ground targets, their planes were almost custom built for this.
 
Which will also require the United States to stay neutral. Once they're in the fight, Germany is doomed.
My personal opinion is that if Sea Lion was launched when intended that the USA would have remained neutral. They were in the last months of an election campaign and with the invasion of Britain I'm not even sure the result of the election would have been the same.
 
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Now we all know that at Toranto it only took 24 aged stringbags to do a considerable amount of damage
Bit of a difference hitting a fleet immobile in port compared to attaking ships mavouvering at sea and banging away with flak. Not saying that renders the He-115s entirely irrlevent, but that they are certainly not some panacea to the RN problem.
 
Bit of a difference hitting a fleet immobile in port compared to attaking ships mavouvering at sea and banging away with flak. Not saying that renders the He-115s entirely irrlevent, but that they are certainly not some panacea to the RN problem.
I never said anything about a mobile fleet but maybe an attack on Rosyth might have been on the cards where elements of the Home Fleet were stationed ready to repel the invasion. It only takes the sinking of one capital ship in an unfortunate position and it could cause untold delays.

Just a thought ...
 

BlondieBC

Banned
Which will also require the United States to stay neutral. Once they're in the fight, Germany is doomed.

I don't think you are right on this one. With the USSR safely neutral and providing at least limited key supplies, many good things happen for the Nazi's.

1) Blockade on Germany is totally ineffective. Russia either sells or reexports critical items to Germany. Stalin's plan was for both sides to bled each other white. He will at least supply enough to keep Germany competitive, and likely will boost when USA enters war. Think almost reverse lend/lease, but Stalin will find something of value to be paid in. Machine tools, joint nuclear program, Turkey, etc.

2) Germany shifts production to what it needs to fight the UK. more subs, naval aviation. Fewer tanks. etc.

3) You almost certainly get some type of Med strategy with a lot more resources than OTL. Things like Malta falling are almost a given. It will be neutralized. North Africa will go a lot better.

4) Might get Spain in war.

5) Likely go into full African strategy, which is what is needed.

6) USA is going to have a hard, hard time finding a place to land in Europe. And wherever it does, it will have to destroy the full German Army, not the 10-20% it did IOTL. And unlike the myth in USA textbooks, the USA will is not unlimited, especially if D-Day is pushed into the 1950's. The USA had about 100 divisions. It could easily need twice this number to seriously fight the German Army on Germany home turf.


7) Nukes are not some miracle weapon, at least not the early ones. And we get into the chemical weapons Germany can respond with. By 1945 ITTL, Germany will be able to hit London hard with multiple weapons systems.

In short, it is not a one sided fight. Germany has a very good chance of a win to a cold peace.
 
Now we all know that at Toranto it only took 24 aged stringbags to do a considerable amount of damage

Um the "stringbags" may have looked old school but they were actually late 1930's aircraft designed specifically for torpedo bombing. The crews were highly trained and arguably the best at torpedo attacks in the world at the time.

You do realize that the attack at Toranto was the pattern that the Japanese used for Pearl Harbor right? That it was the attack that proved it was possible to attack a battle fleet at anchor in a protected harbor using torpedo planes and do it successfully. This was a highly skilled attack that only a few Navies of the time could have pulled off (RN yes, IJN in a year and a half, USN not at the time, Regia Marina maybe but probably not, Germany probably not).

Comparing that to what the Germans had is not actually in the Germans favor.
 
Um the "stringbags" may have looked old school but they were actually late 1930's aircraft designed specifically for torpedo bombing. The crews were highly trained and arguably the best at torpedo attacks in the world at the time.

You do realize that the attack at Toranto was the pattern that the Japanese used for Pearl Harbor right? That it was the attack that proved it was possible to attack a battle fleet at anchor in a protected harbor using torpedo planes and do it successfully. This was a highly skilled attack that only a few Navies of the time could have pulled off (RN yes, IJN in a year and a half, USN not at the time, Regia Marina maybe but probably not, Germany probably not).

Comparing that to what the Germans had is not actually in the Germans favor.
Yeah, sorry I know all this I was just feeling a little cheeky and trying to point out that if 24 British planes could cause damage then so could 138 German planes ... although they didn't have 138 usable torpedos at that time.
 
Yeah, sorry I know all this I was just feeling a little cheeky and trying to point out that if 24 British planes could cause damage then so could 138 German planes ... although they didn't have 138 usable torpedos at that time.

No problem, I just sometimes feel bad for the poor little stringbags that everyone picks on. ;)
 
No problem, I just sometimes feel bad for the poor little stringbags that everyone picks on. ;)
I thought they were excellent little warhorses and would have loved to see the Italians faces when they realised their AA guns were too fast to deal with the slow moving Brits :D
 
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