Operation Sea Lion: The Invasion Itself

Discussion in 'Alternate History Discussion: After 1900' started by Die Kaiserin, Jun 19, 2014.

  1. sitalkes Well-Known Member

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    Yes the harbours were prepared for demolition but the orders were for this to be damage that could be fixed in a week, as it was expected that they would be back in British hands pretty quickly. There is evidence to suggest that the Brandenburg commandos were supposed to attack Dover port frontally from fast boats to prevent it being blocked but that was surely a suicide mission (and pointless if the port was not under attack from the rear as they wouldn't be able to hold the port by themselves). The cranes might be destroyed but many of the German ships had cranes on them. Also, the paratroopers weren't going to drop on any ports, they were going to land near Lympne airfield and attack the ports from the rear in conjunction with the troops from the beaches. A 70% casualty rate was normal for most WW 2 paratroop drops, even the successful ones.
     
  2. oldironside Life is not a third conditional.

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    I was thinking more along the lines of "Racist bigots who live in glass houses shouldn't throw stones." I mean, he was hardly going to pass the entrance requirements for the Waffen SS himself.
     
  3. Michele Well-Known Member

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    Guys, you have me blushing! Thank you.
     
  4. Michele Well-Known Member

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    Isn't it time you let us know where you are excerpting from the parts in a special font?
     
    Last edited: Jun 20, 2014
  5. Michele Well-Known Member

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    No. It's time you read more about Overlord, it will be enlightening for your ideas concerning the sea mammal.

    The Allies didn't unload their stuff on the beaches. Not after June 9, 1944. They brought with them their own prefabricated ports, the Mulberries, and they had them operational in three days. Needless to say the Germans did not have anything like that in 1940. And while we're at it, the Allies also brought along their own fuel pipeline, Pluto. Needless to say the Germans would not have anything like that.

    Comparisons with Overlord only go to show how desperately and foolishly inadequate the pinniped would have been.
     
  6. Riain Well-Known Member

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    Just so we know what we're looking at: some of the 3-4000 German landing craft.
    [​IMG]
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  7. Riain Well-Known Member

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    Perhaps not quite up to Allied standards.
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    Draw your own conclusions.
     
  8. Riain Well-Known Member

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    But that not even really the point, in theory these barges could get over the Channel and land a wave of troops, minus losses from the ready forces. However I seriously doubt they could do it twice, because once Britain reacts in force to a lodgement a handful of destroyers and uboats and some mines plus the Luftwaffe aren't going to stop the RAF/RN/Army who know that the next day or two will be more important than Hastings in 1066. They'll feed in ships and aircraft until the Luftwaffe runs out of ammo and every German ship is sunk and mine detonated, knowing that even if they lose half the RN and all of the RAF they'll still have won.

    If the invading army doesn't get reinforced then it can't move out of the beachhead and defeat the British Army and conquer the country, so the British have nothing to lose by not holding back.
     
  9. oldironside Life is not a third conditional.

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    Ignore. Double post.
     
  10. DoomBunny Well-Known Member

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    You got the maths for this? Per my sources, Dover and Folkstone together, once repaired and operating without interference from RAF, give 1400 tons a day. That's optimal, and factors in no interference whatsoever from the British.

    So, how big is our initial wave then? Because the Germans themselves downscaled the plan when they realised how batcrap crazy it was to land that many divisions.

    Also, have you been to Brighton? The pier has an arcade on it...

    Ever heard of such a thing as a 'Mulberry'?
     
  11. theirishdreamer Banned

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    umm

    - Those 3000-4000 vessels were unarmed floating death traps the second Royal Navy destroyers enter the channel, let alone home fleet. The mult layered "defence" was on paper, in reality the RN warships (which were bigger, better armed and much more numerous) will smash up the resupply forces. I doubt they'd intercept all the 1st wave owing to the fighter cover and risks.
    - Which brings us to the major problem. The 1st Wave will be fully escorted by the Luftwaffe, allowing the Germans to have local channel/beach landing superiority for a few hours - but that's as 1/2 large "waves" ala Eagle Day and after that the Germans get progressively weaker in the air having to now;
    * protect the LZ's from the RAF
    * attack the RN thats entering the channel
    * ground strike missions (bombing airfields etc)
    * supply drops to the LZ's

    All the while having only a limited number of crews, who will tire out fast (1-3 days i suspect) with that level of continuous combat. -> your taking 4/5 sorties a day to maintain a CAP over the LZ's for a few hours. This is all while the RAF has much less pressure relative to before - there forces are near their logistics (giving longer time in the air), have less missions (focus on smashing the beach heads and air superiority), downed pilots are on home territory (generally) and have a better replacement system (during the battle of Britain RAF numbers grew even with losses while Luftwaffe numbers steadily dwindled).
     
  12. Saphroneth Just don't ask me to write a normal world Banned

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    And what does that tell you about what the allies - the people with amphibious experience - thought about the prospects for a Sealion?
    (Add to that that the Allies were overly optimistic about the needs of an amphibious operation, because they felt Dieppe had a chance.)
     
  13. MattII Well-Known Member

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    There's another issue the Germans would have, namely, the size of the Luftwaffe, which has to be split between three tasks:
    1) Protect the barges
    2) Support the landings
    3) Suppress the British

    Each task also has subtasks, which makes it more difficult:
    1) Protecting the barges
    * Sink/damage any British vessels within the sealanes
    * Prevent Bomber/Coastal Command from bombing the flotilla
    * Prevent Fighter Command from strafing the flotilla
    * Prevent any RN ships that make it past the other forces from interfering

    2) Supporting the landings
    * Prevent the RAF from interfering with the landings (this involves shooting down absolutely everything, as even trainers were to be used against the Germans)
    * Destroy British positions and formations near the beaches
    * Ensure the Fallschirmjäger aren't overwhelmed (if they're used)

    3) Suppressing the British
    * Destroy road/rail links to the beaches and ports
    * Destroy any and all equipment that could be used to reinforce the defences
    * Continue to suppress and and all RAF action over the occupation zones

    That is a long list of tasks, and the Germans don't have a hope in hell of covering them all.
     
  14. sitalkes Well-Known Member

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    The Churchill story comes from Invasion: Alternative History of the German Invasion of England, July 1940 (Greenhill Military Paperback) by Kenneth Macksey

    I suggest comparing The Gospels According To Fleming with Notes on German Preparation for Invasion of the United Kingdom, MI 14, 2nd edn. January 1942, especially appendix XXXIII (this is a set of apocrypha used by the Al-Shelion sect of Seelaam). If you look on page 237 of said Gospels it states that "interference by the RAF would reduce port handling capacity by 50%" and an allowance is made for this in the figures. This is despite the fact that some sort of air superiority was a prerequisite for any attempted invasion.

    The tonnages given allow a huge reduction in port efficiency due to damage and RAF interference, as in 1939 a single ship could unload 700 tons a day in a fully equipped port operating at full capacity.
    Fleming says 3,300 tons a day was needed for 11 divisions but only 9 divisions were coming by sea, in three echelons. The first echelon would include the assault forces, backed up by the second echelon which was to arrive by the evening of S+1. The third echelon would arrive on succeeding days. The 11th division would not be arriving until an airfield had been captured and the runway fixed. The 10th division was a parachute division. The total of 11 divisions included six light infantry divisions (mountain, jager, and parachute) which had lower supply requirements than normal divisions. Only when all 11 divisions had landed and all three of their echelons had arrived would they come close to needing the 3,300 tons of supplies. Even then, they would be expected to forage to provide some of their requirements. The full text of the calculations will be published in due course, after which I will fill in the rest of the details.

    The mulberry harbour only unloaded 6,000 out of 54,000 tons a day of supplies- the majority of the rest came off the beaches. American historians even argue that the Mulberry was a huge waste of resources, but I don't agree as it could still be used on bad weather days (when beaches were useless), and it allowed ships to sail directly to Normandy from America instead of going to Britain first (where a huge bottleneck was created by ships having to unload then reload supplies there).

    The invasion fleet was composed of about 2,000 barges and over 1,000 escorts, transports, tugs, and other types of boats and ships, nearly all of which were armed in some way or other. The auxiliary gunboats (of which there were 30) performed well against Russian destroyers, though of course there was nothing (apart from the U-boats, channel guns, mines and aircraft used together) that could match a cruiser.

    The Germans tried several (increasingly sophisticated) designs for unloading ramps but the barges look very like landing craft when you use pictures of the later type of converted barges. They had about twice the space available to the Allies on the beaches so they could land more barges simultaneously.

    Yes, the Luftwaffe had a lot to do, and they were going to do it all with one aircraft at dawn on S-day. They were too busy drinking schnapps to bother trying to use the other aircraft on days leading up to S-day or to read the plan they had set out to enable them to get all the tasks done within the allotted time.
     
    Last edited: Jun 20, 2014
  15. sharlin Banned

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    So..some artillery peices on a tossing, rolling barge with nothing in the way of fire control VS a ship thats bombarding them from 12 miles away can 'match it'? Really? Really? The Wehraboo is strong with you if you belive that.

    Also where are the accounts of these destroyers being dealt with by German invasion barges because this sounds intersting and i'd love to know more about this engagement, where it took place etc other than someone saying 'oh this happened...'

    Also are we to assume that the Germans capture any ports intact? I'm sorry but sneaking troops aboard ships and waiting for the invasion to happen won't work this time and you've got more chance of seeing HRH The Queen streaking at Ascott than a port being taken intact.
     
    Last edited: Jun 20, 2014
  16. cpip "an outlier among outliers"

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    What I love about Sea Lion threads is eating popcorn and watching everyone get increasingly snarky to each other without anyone budging a millimeter from the positions they had at the start of the thread.

    But boy, those Straw Men get obliterated REALLY WELL.
     
    Finbarr the Fair likes this.
  17. Michele Well-Known Member

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    So your sources are fictional works about the success of Eumetopias Jubatus?


    The Mulberry unloaded some 8,000 tons per day and in any case the majority of the British vehicles over the first two weeks. The Americans had lost their Mulberry in the storm (take duly note; the Channel gets hit by storms in June - and in September too), but the sunken breakwaters, which the Allies also had taken along with them, greatly helped operations directly on the beach. Naturally they had LSTs for the bulkier stuff, not river barges.
    Even so, by D-Day+25, the US troops, with no Mulberries, had unloaded an average of 11,500 tons per day; by this time, some 1,000 tons of these were contributed by two small ports that had been captured (and had come into operational use no earlier than June 17 and June 24, even taking into account that the Germans had not extensively sabotaged them).
    The data above come from a respectable, historical source, the US Office of Military History, R.G. Ruppenthal, US Army in WWII: Logistical Support of the Armies.

    Therefore, talking about 54,000 tons per day is meaningless unless one specifies on which damn day. And if you do, please specify the source.
     
  18. Michele Well-Known Member

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    So if submarines, coastal guns, mines and aircraft might be a match for a cruiser, can submarines, coastal guns, mines and aircraft be a match for a convoy moving at 5 knots?
    Because the British had all that stuff, too.
     
  19. alfredtuomi Well-Known Member

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    just putting my popcorn down for a moment to add my bit.

    one should note the cute wooden boxes mounted on the not so pointy end of the barges........judging by the sailor in the pic we might have 2 feet of freeboard,and judging by the amount of rudder out of the water they are unloaded barges we can say maybe a foot of freeboard before those cute boxes make like a plow and slam into a wall of water.interesting.

    now the "landing craft" .take note that the halftrack is being guided down 2 separate ramps which are obviously not attached to the craft ,which terminate at 2 distinct mounds to create a smooth exit to the beach....no doubt created by the group of men casually standing to the right.......should work great with a handful of old men hiding in the bushes with a rifle or two.......hmmmmm

    so very much like the D-day landing craft.......ya sure!!!!!:rolleyes:
     
  20. sharlin Banned

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    Lets not forget its moving at 5 knots if the tide is with it, if its not, then thats a 3 knot convoy. Maybe 2 at worst. :p

    But you know how it generally goes DEUTSCHLAND UBER!