Operation Sealion - creative approach

[Kingfish]

Ok, I understand completely your confusion with my idea.
So let me show you the numbers and clarify out the key points:
1) Regarding the loss of the 2/3 of the merchant fleet - that is big sacrifice, but it becomes quite acceptable considering that it would improve the speed of the invasion fleet to 10 knots instead of 3-4 and make it much more sneaky (100 faster merchants instead of 1000 slow barges) also since these ships will be lying on the shore and not sunk on the bottom maybe they could be partially salvaged after the invasion succeeds.
Also considering the issues at stake 100 merchants are acceptable loss for the potential of germany becoming a superpower.
The allies sacrificed much more ships during the war in the atlantic, only to keep england alive.

Just by reading the above I see that you are thinking one-dimensionally. You seem to be fixated with the actual invasion portion of Sealion, and aren't putting any real thought into the more important follow up. The whole point of Sealion is to knock Britain out of the war, and you won't do that if you dump an invasion force +200,000 strong on her shores and then cut the supply lifeline of said invasion force by 2/3.

Let me put it to you this way, there is no way in hell that a force that big can be sustained by air resupply and initiate sustained offensive actions. Again, look at Stalingrad as an example. How long after the closing of the pocket before the supply situation became grim? Remember, this was an army that was hunker down in a static defensive mode, and prior to the russian offensive had relatively secure LOCs. The Luftwaffe failed to deliver anything close to the amount required, let alone promised by Goering.

Also keep in mind that the 100 merchants will bring significant number of supplies (~60000 ton) which could suffice for the first 2/3 weeks of operation.

Assuming of course that all 100 make it ashore, and not as giant flaming bonfires that will serve as target reference points for British land and Naval artillery.

BTW, how exactly will the Germans unload +1000 tanks, HTs and heavy artillery from ships that have run aground on a hostile beach? Sorry, no RO/ROs here.

If you need to land under threat of enemy fighters and unload the planes that alone drops your throughput ten times at least.

And for every ME109 that is escorting a Junkers is one less that is escorting the Dorners and JU88s. No bombing runs over RAF bases means the RAF now can concentrate on - you guessed it - fat, slow Junkers flying low and slow over the invasion beaches. You either cut back on the bombing of RAF bases, and give the Brits the breather they so desperately needed, or cut back on the resupply runs and hope the invasion force doesn't resort to cannibalism.

[Ostkatze]

So we're not partaking in any Alice in Wonderland fantasies here?

Let's say we popped up 200-400 concrete bunkers for our Ju52's; thousands of containers to be pushed out side doors, carrying ammo and fuel ( and hopefully not Red Devil hats ) that will magically not burst and float ashore. OK.

But our daily operational 200-odd Ju52's ( @ 2ton per trip ) will bring in 4000 tons? Day in day out? TEN SORTIES A DAY?

Yes, we've gone to great lengths to point out the brevity of the trip. However, back in the real world of '39-'45 aircraft ops. - ten sorties a day?

My old man and his pals, in a very well supported op., only had a 22-23 minute flight between Wunsdorf and Gatau. He made 63 trips into Berlin, sometimes 2 a day, only twice 3 times in one day. Yes, they were unloading. But delivering some serious tonnage of fuel oil and stuff. Incidentally, he told me after it was done that he thought it was hairier coming into an icy field with one ahead of you and another right behind, than a night trip over Happy Valley.

Today they fly commuter planes like no.10 buses day in day out. Not the case for aircraft in those days. np.

[Ostkatze]

Forgot to mention, while scheduling these 10 drops a day, ( at random, in order to throw off the RAF ) all at high tide, to allow for low tide pick-up, how are we going to arrange for the rate and timing of these suddenly numerous " spring tides " ? np27.

[kalpazanin]

Just by reading the above I see that you are thinking one-dimensionally. You seem to be fixated with the actual invasion portion of Sealion, and aren't putting any real thought into the more important follow up. The whole point of Sealion is to knock Britain out of the war, and you won't do that if you dump an invasion force +200,000 strong on her shores and then cut the supply lifeline of said invasion force by 2/3.

Who said the supply is to be cutted of?!?
As my previous numbers show with only 200 Ju 52 there can be a 4000 ton/day supplies dropped to the shore water.

Let me put it to you this way, there is no way in hell that a force that big can be sustained by air resupply and initiate sustained offensive actions. Again, look at Stalingrad as an example. How long after the closing of the pocket before the supply situation became grim? Remember, this was an army that was hunker down in a static defensive mode, and prior to the russian offensive had relatively secure LOCs. The Luftwaffe failed to deliver anything close to the amount required, let alone promised by Goering.

The 250000 6th army at stalingrad was holding out for more than 2 months against 90 soviet divisions fully equipped with modern tanks and huge amounts of artillery.
During that time they were sustained by air supply only.
And the LW didn't have the option of dropping the cargo - the planes had to land on limiting airstrips which lowers the effectivity of the operation tenfold.
If you add my idea of fast dropping of supplies in the water and replace the 90 powerfull soviet divisions with whatever feeble forces the english had available you must see where the result would be...

Assuming of course that all 100 make it ashore, and not as giant flaming bonfires that will serve as target reference points for British land and Naval artillery.

Considering the 6 hour crossing time of the channel and the more or less equal force of the KM with the RN immediately available in the channel I'd say it's not impossible that all make it safely ashore. However even if ~75% make it trough that still would be more than enough.

BTW, how exactly will the Germans unload +1000 tanks, HTs and heavy artillery from ships that have run aground on a hostile beach? Sorry, no RO/ROs here.

As I previously explained, after running aground the ships will be stabilized vertically by number of rods dropped from their sides. When the tide goes low enough so that the ships are not in water, the front sections of the ships will be blown by prepositioned explosives.
After that from the lower deck a ramp will be lowered to the beach.
All the heavy equipment (tanks) will be on lower deck and can then roll onto the beach, the lighter equipment could be lowered from upper deck(s) by ships own cranes.

And for every ME109 that is escorting a Junkers is one less that is escorting the Dorners and JU88s. No bombing runs over RAF bases means the RAF now can concentrate on - you guessed it - fat, slow Junkers flying low and slow over the invasion beaches. You either cut back on the bombing of RAF bases, and give the Brits the breather they so desperately needed, or cut back on the resupply runs and hope the invasion force doesn't resort to cannibalism.

You somehow misunderstand the whole idea of warfare strategy. Let me explain:
a) At any given time there are N number of RAF planes and K LW planes.
b) The close the fight of these is to the german bases, the longer the Me109E's can be in the air and the less shot down RAF pilots can be retrieved.
c) The close the fight of these is to the german bases, the less use would RAF have of their Radars.

So from the above you must understand that attacking 30 minute sorties would be at most an act of desparation for the RAF in such situation. It would lead to much quicker disaster than saving their breath and keeping the fighter squadrons close to their inland bases.

[kalpazanin]

So we're not partaking in any Alice in Wonderland fantasies here?

Let's say we popped up 200-400 concrete bunkers for our Ju52's; thousands of containers to be pushed out side doors, carrying ammo and fuel ( and hopefully not Red Devil hats ) that will magically not burst and float ashore. OK.

What 'Red Devil hats' that float ashore? What are you talking about?!?
I don't follow.

But our daily operational 200-odd Ju52's ( @ 2ton per trip ) will bring in 4000 tons? Day in day out? TEN SORTIES A DAY?

Again ,look at the performance of the Stukas on the eastern front - they were doing sometimes non stop flying for hours and hours with each mission -20 minutes, drop bombs, land , get bombs (not always refueling!) and fly again - and they were searching for quality targets.
In my idea there isn't even such searching neccessary - just find the shoreline.

Yes, we've gone to great lengths to point out the brevity of the trip. However, back in the real world of '39-'45 aircraft ops. - ten sorties a day?

My old man and his pals, in a very well supported op., only had a 22-23 minute flight between Wunsdorf and Gatau. He made 63 trips into Berlin, sometimes 2 a day, only twice 3 times in one day. Yes, they were unloading. But delivering some serious tonnage of fuel oil and stuff. Incidentally, he told me after it was done that he thought it was hairier coming into an icy field with one ahead of you and another right behind, than a night trip over Happy Valley.

Today they fly commuter planes like no.10 buses day in day out. Not the case for aircraft in those days. np.

I'm glad you share that info, one of the great things about this site is that many people have personal experiences related to WWII activities.
However as you noted yourself - they were landing and unloading on the destination point...
That in itself reduces the efectiveness at least twice.
Much more if the target landing strip has limited capacity - then the planes must circle in the air awaiting landing window.
It also depends on how streamlined the process of loading and unloading is. In the case I'm describing the loading will be as fast as attaching bombs - several minutes,and the unloading as fast as dropping bombs.

[kalpazanin]

Forgot to mention, while scheduling these 10 drops a day, ( at random, in order to throw off the RAF ) all at high tide, to allow for low tide pick-up, how are we going to arrange for the rate and timing of these suddenly numerous " spring tides " ? np27.

As I previously stated the spring tide is neccessary for the ships, not for the plane drops - the later can be done at any tide level, which is significantly higher than the low tide.
Let's say that gives ~80% of the tide's time cycle.
spring/neap tide is irrelevant here.

[kalpazanin]

So we're not partaking in any Alice in Wonderland fantasies here?

Let's say we popped up 200-400 concrete bunkers for our Ju52's; thousands of containers to be pushed out side doors, carrying ammo and fuel ( and hopefully not Red Devil hats ) that will magically not burst and float ashore. OK.

But our daily operational 200-odd Ju52's ( @ 2ton per trip ) will bring in 4000 tons? Day in day out? TEN SORTIES A DAY?

Yes, we've gone to great lengths to point out the brevity of the trip. However, back in the real world of '39-'45 aircraft ops. - ten sorties a day?

My old man and his pals, in a very well supported op., only had a 22-23 minute flight between Wunsdorf and Gatau. He made 63 trips into Berlin, sometimes 2 a day, only twice 3 times in one day. Yes, they were unloading. But delivering some serious tonnage of fuel oil and stuff. Incidentally, he told me after it was done that he thought it was hairier coming into an icy field with one ahead of you and another right behind, than a night trip over Happy Valley.

Today they fly commuter planes like no.10 buses day in day out. Not the case for aircraft in those days. np.

Also let's not forget that the LW had more 1500 bombers available in addition to the transports.
Considering the importance of the supply line any number of those could be included in the supply operation.

[Robert Rojas]

Greetings to both citizen Kalpazanin and the community as a whole. Well sir, in light of your introductory posting of Thursday - December 07, 2006 - 4:47pm, old Uncle Bob certainly does admire your optimism with the odds of the Wehrmacht establishing a coherently supported bridgehead in southern England during the course of the Summer of 1940. Given that the Wehrmacht had neither a theoretical doctrine nor any substantive technical experience with classic amphibious warfare, have you taken into consideration what the physical and mental condition of the common landser just might be once he "successfully" disembarks from his improvised "landing" craft in the surf of some obscure beach in Britannia? Most people do not function very well when afflicted with seasickness and hypothermia. Do you really feel that the first wave of wholly inexperienced Wehrmacht infantry formations will be able to pull themselves together out of this funk before the British or the Canadians launch the inevitable counterattack? It's just some sobering food for thought. Dramamine anyone? Well, that's my initial two cents, pence or pfennigs worth on this exceptionally bizarre topic of interest - for now anyway. In anycase, I would like to bid you a copacetic day over in your corner of greater Europe.

Best Regards,
Uncle Bob

[kalpazanin]

Greetings to both citizen Kalpazanin and the community as a whole. Well sir, in light of your introductory posting of Thursday - December 07, 2006 - 4:47pm, old Uncle Bob certainly does admire your optimism with the odds of the Wehrmacht establishing a coherently supported bridgehead in southern England during the course of the Summer of 1940. Given that the Wehrmacht had neither a theoretical doctrine nor any substantive technical experience with classic amphibious warfare, have you taken into consideration what the physical and mental condition of the common landser just might be once he "successfully" disembarks from his improvised "landing" craft in the surf of some obscure beach in Britannia? Most people do not function very well when afflicted with seasickness and hypothermia. Do you really feel that the first wave of wholly inexperienced Wehrmacht infantry formations will be able to pull themselves together out of this funk before the British or the Canadians launch the inevitable counterattack? It's just some sobering food for thought. Dramamine anyone? Well, that's my initial two cents, pence or pfennigs worth on this exceptionally bizarre topic of interest - for now anyway. In anycase, I would like to bid you a copacetic day over in your corner of greater Europe.

Best Regards,
Uncle Bob

Hello Robert,
While seasickness is quite an unpleasant phenomena (I've experienced it several times), I think you greatly overestimate it's effect in the given scenario.
The reasons are:
1) The germans allready did invade Norway by sea, traveling much greater distances than the channel crossings and their soldiers were performing quite well.
So well that in fact they successfuly captured Norway under the noses of the combined Norway, French and British forces.
2) The 6 hours of the initial channel crossing would be obviously not choosen to be during storm.
So we are talking of maximum sea level 2-3. It takes awhile to get seasick
in such conditions. ~6 hours would be completely bearable.

As to the unexperienced part... you are puzzling me..
Those were the most experienced and tough soldiers in the world at that point!

I would like to bid you a copacetic day over in your corner of greater Europe.

I cannot understand what you're saying here.. too complicated for my little brain..

[LWD]

You aren't saying the transport planes can do a complete sorty in 30 minutes are you? ..

Why not? Consider the distance, the average speed of the airplanes and that's what you get.

It also takes time to take off, form up, gain altitude, and land.

.
As to the RAF bomber attacks - that is possible, but it will force them to "Battle of Britain" in reverse (shot british pilots cannot be recovered)- that alone could bring the RAF to it's knees.

That's why I said night bombing. Not real efficient but safer.

Also the idea is to prepare enough air strips in advance. The transports will be placed in concrete hangars - so little damage to the airstrip will be acceptable price for numerous RAF bombers shot.

Do you have any idea how long this would take? Just getting the concrete and building the hangers would take months. And of cousre large transports have more problems with cratered runways.

Not exactly. I didn't mean during the maximum point of the high tide - I meant when tide is somewhere sufficiently above the low point - that leaves ~80% of the tidal time cycle available for the drops.

And just what do you think the recover rate on these supplies will be? First they have to land without bursting. If they hit in too shallow a water they will impact the bottom and likely break or at least rupture and fill with water. If they land without busting up if they sprin a leak they will sink. If not they may well float away. If a rip tide occurs they will almost assuredly be washed miles down the coast. The there will be the problem of the British doing what they can to interfere with this effort. You'd be lucky to get 10% of the supplies dropped to the troops.

The LW didn't do a very good job of escorting bombers why do you think they could do a better job with transports..

Becouse the situation is completely different. ..
[/quote]
No. While the RAF might not intercept as often when they did they would probably be quite successful. German escort theory like early allied escort theory was flawed. As for the frequency of intercepts were I the RAF I'd put on several large sweeps a day. With all the flying you have the LW doing they be bound to intercept significant numbers of bombers or transports and have the fighters to outnumber the LW fighters on the scene.

I agree with you that deceiving the enemy of your intentions is a tricky business. However the british knew very well that the barges were to be used for the invasion and the merchants for a supply line afterwards.
Therefore they wouldn't conceive any german invasion without the barges.
The transports could be loaded a month before and kept in the docks - the constant threat could be perceived by the british as 'bluffing'.

They might not think the Germans were going to invade but they would certainly think something was up and something that they would want to stop. Probably even worth positioning a few subs off these ports. Certainly worth watching and intercepting if given the chance. And by the way you can't load everything on board ahead of time.

Even if british try to sink the loaded transports, when we consider their success rate of 10% with the rows of barges lying packed in the ports,that indicates it's an acceptable risk.
The troops could be brought on board the ships very fast just before sailing- how long does it take for a disciplined german soldier to climb on board?

Well you also have to move them all to the ports make sure they find the right ship that sort of thing. I seam to recall the allies taking several days to get the Normandy invasion fleet loaded (could be wrong on this)

As to the lag of meeting at sea they should be synchronized to sail to their destinations on small groups (5-10ships) timed the same way as the Norwegian invasion was timed - no 'big fleet' assembly in the middle of the channel.
Considering the number of the ships and german precision that shouldn't be so difficult.

So you have small groups either unescored or with 1 KM warship sailing? Even an MTB or two will likely cause problems in that case.

If it's at night what good will the LW do?

Since it's a spring tide there'll be a full moon. LW will be less effective than at daytime ,but still a force to be reckoned with.
[/quote]
So now the LW is going to be able to intercept British bombers and ships at night?

Also the Germans will have to provide CAP over the invasion fleet on a contunuous basis while the British can choose the time to mass against it. In general subs didn't do all that well vs warships at combat speeds. They will also have to be pre positioned or they will have a hard time keeping up with the fleet even on the surface.

The moment the merchants exit ports the LW will send all its bombers to lay mines in all south england ports - that alone could keep the RN busy for a day...
[/quote]
But it's at night remember? and they are also intercepting the RN. They may get some mines where they will cause problems but they also may end up mining the invasion beaches as well. Night bombing (minng is just another form of bombing) was not very accurate at this point in time.

The subs will lay waiting at various points along the path of the invasion force.

The invasion forces route is going to take it through some very well traveled waters. How many of the subs are going to be spotted and lost before the invasion fleet even sails?

...The ships would sail from Le Havre, Boulogne, Calais and Dunkerque. The maximum
length would be from Le Havre~120km.
With speed of 10-11 knots it would be crossable in ~ 6 hours.

Probably not. Even without zig zaging there will be currents and winds that will cut your effective speed. The if a RN ship gets close or the ships are subject to a bombing attack there will be additional time due to maneuvering and confusion.

No. Among other things there is the problem of hull speed. But in any case doubling the motive power does not come anywhere near doubling the speed of a vesel. In the case of barges doubling their speed would probably mean that the British wouldn't even have to worry about sinking them.

That's debatable.
The tugs could do 11 knots and the long barge's hull speed would be less than its overall water drag.
Also if such barge is only partially loaded and towed by 4 tugs it's front hull profile would provide some lift.
Anyway in the worst case there'll be 100 such big barges sailing only from Calais and Boulogne at 7knots. That still brings some additional assistance to the main force.
[/quote]
Just did some calculations and hull speed is not likely to be a problem. HOwever those barges were never designed to be moving at 10 knots. Since they were designed for slower speeds not much attention was paid to streamlining them so if you try to pull them that fast particularly in the ocean where they will be subject to additional forces due to waves their structural integrity is not guaranteed at all. Also consider that speed and horspower increases are not linear in fact for cars the air poer required to overcome air resistance is porportional to the cube of the velocity. So doubling the speed would take 8 times the power. By the way can the tugs do 11 knots with a tow?
[/quote]

How long a ramp are you proposing? I suspect if you look at the beach topaographys in many cases the transports will run aground 10s of meters from the beach. If there is a bar as many beaches have it can be even further. Then there is the question of how likely it is the ship will flood when the tide rises again or a rogue wave comes by.

While if planning properly such occasions shouldn't happen we all know that in real life things do get messed up.
For such cases each ship will carry several sections of ponton bridge in it's deck and teams of engeneers who will help to breach the lacking distance to the shore. Also all the available small boats and the small barges would be used to make a short floating bridges from such unlucky ships to the shore.
[/quote]
The topology of the British beaches may well not be known. Even if it is know it can change rather quickly (one major storm can do it). I've been on beaches where you transports couldn't have gotten within half a mile of shore. Note that you have just cut into your combat loading with a fair amount of additional mass. Oh and buiding you bridge is going to take a while; unfortunate if the RN or RAF show up while it's under concstruction don't you know.

The flooding of the ship is no problem - it allready sits firmly on the ground so it can't sink.

It can flood. The hold is presumably full of cargo at least some of it you don't want getting wet. Then there is the problem of it shiffiting the center of gravity. IF the bow is aground but there's an addtional 10 or 20 feet of water under the stern what do you think will happen?

Previous discusions have shown that the Home fleet can be at the invasion beaches in less than 24 hours. ....

Most of the home fleet was dispersed away from the channel - so in order to do that they'll have to clean the mines at the port entrances placed by the LW and completely annihilate the KM - considering the forces involved that will take at the very least 2 days.
[/quote]
The Home Fleet wouldn't have to enter the ports so the mining isn't going to slow them at all. As for the KM the home fleet goes for the transports and the invasion forces. If the KM elects to interfere there is no reason that the British couldn't render it combat ineffective in a much shorter period of time than days minutes to hours. Look how quickly the US destroyed a porportionally stronger Japanese force in the Surigao strait.

Also since according to this proposal the invasion force has artillery and armor it can proceed with little assistance from the LW at least for the first couple of days.
This leaves the Home fleet at the complete mercy of the LW close to later's bases in France.

The British fleet is also close to RAF bases as is the invasion force. It would also have plenty of AA ammo and could retire to friendly ports when required. Hardly at the complete mersy.

And even if we put aside all of the above the invasion force will be quite capable of returning fire at least to the destroyers.

Are you talking about tanks and field guns duelling DDs? Historically this didn't work out well for the tanks and guns. Then there is the problem that they will have a limited amount of ammo, which is one of the harder things to resupply by the way, and while they are playing with the DDs they can't be supporting the troops. Or were you talking about them doing this while they are still at sea? If so their fire control is going to be abismal at least until they take the first fish then it will be nonexistant.

By the way have you even looked at the time lines for this. Looks to me like you have proposed enough modifications and constrution so that this invasion couldn't happen until after September at best. If that's the case it's clearly a no go.

[Kingfish]

Who said the supply is to be cutted of?!?

You did say you were grounding 100 out of 170 available merchant ships, right? Those ships are the only you will adequately supply the invasion force for sustained offensive operations.

As my previous numbers show with only 200 Ju 52 there can be a 4000 ton/day supplies dropped to the shore water.

Any thought on the engineering behind this method? How deep must the water be for a hollow cylinder packed with 2 tons of supplies to survive the impact?

What height must the cannister be dropped? What airspeed?

Forget about parachutes - once it hits the water you'll end up with a giant sea anchor that would make retrivale next to impossible. If the lines are cut then you have several hundred free floating sea anchors waiting to foul up the next batch of cannisters.

You certainly can't unload them in waist deep water, not via airdrop, so now you have to take into consideration how to A) retrive them in deep water - and - B) drag them up across the shallows to where you can unload them safely. And while your retrival detachment is struggling with the mechanics of this little engineering gem another +100 Junkers are lining up for their drop.

The 250000 6th army at stalingrad was holding out for more than 2 months against 90 soviet divisions fully equipped with modern tanks and huge amounts of artillery.
During that time they were sustained by air supply only.
And the LW didn't have the option of dropping the cargo - the planes had to land on limiting airstrips which lowers the effectivity of the operation tenfold.
If you add my idea of fast dropping of supplies in the water and replace the 90 powerfull soviet divisions with whatever feeble forces the english had available you must see where the result would be...

Sorry, but an air supply campaign that is delivering less than the absolute minimum of food, ammo and other basic supplies is not sustaining an army.

Considering the 6 hour crossing time of the channel and the more or less equal force of the KM with the RN immediately available in the channel I'd say it's not impossible that all make it safely ashore. However even if ~75% make it trough that still would be more than enough.

And RAF bombing runs on the lines of grounded merchant ships? How about British land artillery?

As I previously explained, after running aground the ships will be stabilized vertically by number of rods dropped from their sides. When the tide goes low enough so that the ships are not in water, the front sections of the ships will be blown by prepositioned explosives.
After that from the lower deck a ramp will be lowered to the beach.
All the heavy equipment (tanks) will be on lower deck and can then roll onto the beach, the lighter equipment could be lowered from upper deck(s) by ships own cranes.

So we run aground in the high tide in order to get the ships as close to the shore as possible, then wait 6 hours for the low tide before we begin rolling off the heavy equipment? To paraphrase Col. Kilgore from Apocalypse now - "The tide doesn't go out for 6 hours. You want to wait here for 6 hours?"

b) The close the fight of these is to the german bases, the longer the Me109E's can be in the air and the less shot down RAF pilots can be retrieved.
c) The close the fight of these is to the german bases, the less use would RAF have of their Radars.

This still does not address how these Me109s will be escorting Junkers over the invasion beaches and Dorners over the RAF bases at the same time. They can't, so one mission will have to either go without adequate escorts, and risk heavy losses (which makes follow up mission less effective, which makes the enemy stronger, which means heavier casualties) or not at all.

So from the above you must understand that attacking 30 minute sorties would be at most an act of desparation for the RAF in such situation. It would lead to much quicker disaster than saving their breath and keeping the fighter squadrons close to their inland bases.

There certainly will be desperation, but I think you are attributing it to the wrong side. Once the Germans realize that, after depositing an army group on a foreign shore with their backs to the sea (and no way to get them out now that all of the transports that brought them in had their front hulls blown off by prepositioned explosives) that their air resupply campaign will never deliver the necessary amount of tonnage to sustain them, then desperation will really kick in.

[Polynikes]

Interesting read so far....

OK here's my thoughts. It took the allies DAYS to load the invasion force in 1944 - the German army would have even more trouble because of the inappropriate nature of their invasion ships.

Therefore the British will know something is up.

Secondly, these invasion ships are something of a fantasy - even if you could group 100 of them, no way will they take 2,000 men plus a company of tanks and a company of half-tracks.
If you DID cram that much in, they'd take much longer to unload and you can forget any crazy ideas of detonating explosive charges INSIDE the ships to miraculously turn them into Ro-Ro ferries.

As for the exploding stabilisation rods to turn beached merchant ships into landing docks...sheer fantasy.

A beached merchant ship would be a hell of a place from which to get off alive at high tide. You would get a lot of drowned troops and a lot of lost equipment/supplies.
Not to mention you would never land a single piece of heavy equipment.
Your tanks and halftracks & any artillery are lost - incidently I didn't see any reference to prime movers - unless horses are also meant to be shipped across?

OK, 100 ships carrying 2,000 men each means 6 or maybe 7 INFANTRY divisions without trucks or artillery & only the supplies they carry in their rucksacks.

Let's say just 10% of them don't make it or don't beach correctly = 180,000 men soaked and very cold men stumbling around on a dark beach.

It would take DAYS to asemble them into a coherrent force - at best they would resemble an armed band. Their only chance would be to focus on taking at least two ports - say Portsmouth and Dover.

Supply, I think, has been pretty much ruled out so it would effectively be the largest ever escalade in history.
(One point not mentioned is that there is not a single "supply" item, there are thousands of items that need to be supplied and it takes a massive and thoroughly efficient logistics effort to get it right).

Supply by air doesn't work and has NEVER worked (at least for large scale operations).

Stalingrad failed.
Dien Bien Phu failed.
Arnhem failed.

It would be a one-shot attempt to sieze and hold two or more ports in a similar way that British airborne forces tried to hold Arnhem.

EXCEPT these ports were defended (IIRC Dover was defended by the Royal Marines).

Many who draw up succesful Sealion operations tend to ignore the British response - especially that from its capital ships main armament and Bomber Command.
The Short Stirling had just been made operational in the Summer of 1940 (though hadn't flown any operations). One could assume it would be employed to carpet bomb the beacheads along with the rest of Bomber Command.

Fighter Command would focus on the German transport aircraft - including bombers.
Incidently, dropping supply containers into the sea is the caziest idea I've ever heard - and no, you don't have 80% of the day to do it. Assuming your pods float and don't break apart they'll cary very little in the way of supplies and float away...others will simply supply the British defence forces.

British land forces ammounted to approx 2 divisions and about 100 tanks. You could expect these to be used to defeat the German forces that made it ashore within HOURS of them landing and still sorting themselves out.

Essentially you'd have several densely populated beacheads that didn't so much resemble the 5 beaches on D-Day but rather they'd resemble the beaches around Dunkirk in May 1940.

The Dieppe raid showed just how hard it is for lightly armed troops to take a port - it caused the allies to decide it wasn't possible and to seek alternative arrangements to landing supplies - the Mulberry harbours.

In reality this is the key - D-Day was a massive logistical effort with massive resourses behind it and with complete air superiority coupled with a fleet of purpose built ships, landing craft, underwater pipelines etc etc etc.

Sealion was a bluff - nothing more.

A cross channel invasion can't be done on the cheap. Had the Germans tried it, it would've ended in certain failure.

[kalpazanin]

It also takes time to take off, form up, gain altitude, and land.

If you remember in my previous post I specifically stated that the building of numerous airstripes in the Calais area would be essential.
If given priority in the 84 days of Sealion preparation a significant number of such would be prepared.
Therefore the transports would not have to wait each other for takeoff or landing. - From the time the plane engines are running to the actual take off there may be couple of minutes.
Likewise for the landing.
As to the formation forming, they need not make a big formation - each squadron will have it's own dropping area and since they will take simultaneously and the distance is so short, they will get back approximately at the same time and hide inside their hangars.

That's why I said night bombing. Not real efficient but safer.

The british were very inefficient at night bombing at that time.
They had some very unrealistic ideas of navigating night bombing by the stars, which usually led to dropping their bombs kilometers from targets.
It took more than an year for them to fix this problem...

Do you have any idea how long this would take? Just getting the concrete and building the hangers would take months. And of cousre large transports have more problems with cratered runways.

The sealion invasion had 84 days for preparation.
Since we are talking about building a simple concrete structures and rude airstripes - low qualification work, it's not like taking resources and workforce from the tank or plane or ship building.

Given the amount of POW's available to the Germans such work in given timeframe, seems completely realistic to me.

And just what do you think the recover rate on these supplies will be? First they have to land without bursting. If they hit in too shallow a water they will impact the bottom and likely break or at least rupture and fill with water. If they land without busting up if they sprin a leak they will sink. If not they may well float away. If a rip tide occurs they will almost assuredly be washed miles down the coast. The there will be the problem of the British doing what they can to interfere with this effort. You'd be lucky to get 10% of the supplies dropped to the troops.

The dropping of the supply cylinder is not very different in it's physics from dropping of torpedo by torpedo bomber.
Torpedoes filling consisted of explosives and fuel as well as delicate mechanical parts, which as factual events show were not affected by the drop. (otherwise they wouldn't have worked)

The only difference in proposed idea would be that the cylinder would be dropped with slight angle to the horizon (~15 degrees) so when it hits the water it's horizontal kynetic energy will be partially transformed to lift, which will slow it's sinking speed until it's horizontal speed is neutralized.
Even if the cylinder ruptures for some reason, the supplies would not be damaged much by little water - otherwise no military operations could be possible during rainy days...

The only possible problem is if the pilot is such a complete idiot, that he drops it on the very beach - well, even then some of the cargo could be salvaged (food or bullets for instance)
My overall expectations are that after gaining some initial experience 95% of the said supplies could be retrieved during low tide.

No. While the RAF might not intercept as often when they did they would probably be quite successful. German escort theory like early allied escort theory was flawed. As for the frequency of intercepts were I the RAF I'd put on several large sweeps a day. With all the flying you have the LW doing they be bound to intercept significant numbers of bombers or transports and have the fighters to outnumber the LW fighters on the scene.

Haha So the RAF would have to do several large sweeps with fighters over the channel??
That alone would lead to RAF forces being decimated - remember that the RAF won BoB only by rebasing it's fighters further inland and carefully preparing interceptions as close to it's bases as possible.
The moment you force them to start such bold patrols it's like you've given up their only acceptable strategy.

They might not think the Germans were going to invade but they would certainly think something was up and something that they would want to stop. Probably even worth positioning a few subs off these ports. Certainly worth watching and intercepting if given the chance. And by the way you can't load everything on board ahead of time.

Thinking 'something is up' and knowing exactly what is 'up' are veeery different things.
Look at operation Cerberus for instance - the british though 'something is up', but that just didn't cut it..

English subs were inferior to the u-boats and took quite a beating during the norwegian campain.
British could in no way could have used them for prolonged blockade - they would just be sunk one by one in the first week and then brits would call the rest off.

Well you also have to move them all to the ports make sure they find the right ship that sort of thing. I seam to recall the allies taking several days to get the Normandy invasion fleet loaded (could be wrong on this)

As I posted previously the equipment would be loaded to the ships, but the troops themselves would board at the last moment. If executed with planned precision this could take no more than a couple of hours.
In the month previous to the actual invasion the germans could do several such massive drills with the barges instead of the ships in order to create an illusion of 'bluffing' in the english side.

So you have small groups either unescored or with 1 KM warship sailing? Even an MTB or two will likely cause problems in that case.

While the MTB boats would be a threat to the barges, the Merchants armed with several big guns and AA on deck would be capable of fending off such attacks. (Remember the Kormoran?)
The KM warships will operate by LW intelligence and try to intercept any force sent against the convoy.

If it's at night what good will the LW do?

It would be full moon (spring tide) and the RN ships/planes will be sufficiently identifiable.

So now the LW is going to be able to intercept British bombers and ships at night?

You seem to contradict yourself - if the LW is unable to see the british ships then how are the british bombers seeing german ships??
Likewise the opposite. You cannot claim that by some magic only RAF pilots see and LW are blind..

But it's at night remember? and they are also intercepting the RN. They may get some mines where they will cause problems but they also may end up mining the invasion beaches as well. Night bombing (minng is just another form of bombing) was not very accurate at this point in time.

The mining from planes is just dropping the mines in the approximate area - they don't need to hit targets with precision.
As to the mining of the invasion beaches - you take the LW bomber pilots for a complete idiots...

The invasion forces route is going to take it through some very well traveled waters. How many of the subs are going to be spotted and lost before the invasion fleet even sails?

The subs would be positioned there in the previous day or so - that's very short period for any serious harm from the RN patrols.

Probably not. Even without zig zaging there will be currents and winds that will cut your effective speed. The if a RN ship gets close or the ships are subject to a bombing attack there will be additional time due to maneuvering and confusion.

Before the RN starts intercepting the invasion fleet it will have to :
a) Find it.
b) Group it's available forces in the imediate area of the channel.
c) Clear the ports of mines so warships not on patrol can embark.
d) Intercept the fleet.

All these take time. (If you disagree look again at operation Cerberus)
By the time they start dispatching their first battle groups and removing the mines from their ports entrances the fleet would be half way.
Even when they intercept, they will not be in full force and the KM+LW will be able to deal with it.

Just did some calculations and hull speed is not likely to be a problem. HOwever those barges were never designed to be moving at 10 knots. Since they were designed for slower speeds not much attention was paid to streamlining them so if you try to pull them that fast particularly in the ocean where they will be subject to additional forces due to waves their structural integrity is not guaranteed at all. Also consider that speed and horspower increases are not linear in fact for cars the air poer required to overcome air resistance is porportional to the cube of the velocity. So doubling the speed would take 8 times the power. By the way can the tugs do 11 knots with a tow?

Ok. I allready agreed - the barges will do 7 knots with 4 tugs and therefore will sail only from Calais and Boulogne - still well within the 6 hour mark.

The topology of the British beaches may well not be known. Even if it is know it can change rather quickly (one major storm can do it). I've been on beaches where you transports couldn't have gotten within half a mile of shore. Note that you have just cut into your combat loading with a fair amount of additional mass. Oh and buiding you bridge is going to take a while; unfortunate if the RN or RAF show up while it's under concstruction don't you know.

The germans were constantly photographing the english coastal areas from the air.
Since during low spring tides all the beaches are uncovered from water, the knowledge can be quite precise.

The flooding of the ship is no problem - it allready sits firmly on the ground so it can't sink.

It can flood. The hold is presumably full of cargo at least some of it you don't want getting wet. Then there is the problem of it shiffiting the center of gravity. IF the bow is aground but there's an addtional 10 or 20 feet of water under the stern what do you think will happen?

Absolutely nothing. The ship will get floaded with water up to the waterline. Since it will lay on the bottom it's keel will be in full contact with the ground all the time.
All the supplies, which are water sensitive will be on the upper deck. The rest probably wouldn't be damaged by 6 hours in the water.

The Home Fleet wouldn't have to enter the ports so the mining isn't going to slow them at all. As for the KM the home fleet goes for the transports and the invasion forces. If the KM elects to interfere there is no reason that the British couldn't render it combat ineffective in a much shorter period of time than days minutes to hours. Look how quickly the US destroyed a porportionally stronger Japanese force in the Surigao strait.

Not enter, but exit. Only part of the fleet was on constant patrols - the rest was in ports.
As to the purely marine combat look at the numbers:
RN (english channel immediate fleet) :3 Light cruisers 17 destroyers + MTB boats
KM 10 destroyers + 25 u-boats + 18 s-boats
Considering the Norway campain, the quality of the german naval forces was as good as the British.
Providing the support of LW in the chanel I wonder if they may even win the first battle...

Are you talking about tanks and field guns duelling DDs? Historically this didn't work out well for the tanks and guns. Then there is the problem that they will have a limited amount of ammo, which is one of the harder things to resupply by the way, and while they are playing with the DDs they can't be supporting the troops. Or were you talking about them doing this while they are still at sea? If so their fire control is going to be abismal at least until they take the first fish then it will be nonexistant.

I'm talking of 100 mm and 155 mm caliber guns as well as 88 mm caliber guns shooting from merchan't decks
In case of the Kormoran those sunk a light cruiser!

By the way have you even looked at the time lines for this. Looks to me like you have proposed enough modifications and constrution so that this invasion couldn't happen until after September at best. If that's the case it's clearly a no go.

The start should be sometimes in middle of september. That should be sufficient for all the improvisations.

[redcoat]

After reading this thread, I can understand why the term 'creative' accounting is used to to describe any financial accounts that have no basis in truth.
Its pure schoolboy fantasy !

[kalpazanin]

As my previous numbers show with only 200 Ju 52 there can be a 4000 ton/day supplies dropped to the shore water.

Any thought on the engineering behind this method? How deep must the water be for a hollow cylinder packed with 2 tons of supplies to survive the impact?
What height must the cannister be dropped? What airspeed?
Forget about parachutes - once it hits the water you'll end up with a giant sea anchor that would make retrivale next to impossible. If the lines are cut then you have several hundred free floating sea anchors waiting to foul up the next batch of cannisters.

You certainly can't unload them in waist deep water, not via airdrop, so now you have to take into consideration how to A) retrive them in deep water - and - B) drag them up across the shallows to where you can unload them safely. And while your retrival detachment is struggling with the mechanics of this little engineering gem another +100 Junkers are lining up for their drop.

My general idea was to drop cylinders of the same size and weight as torpedoes dropped from torpedo bombers.
The calculations for these are widely available.
The only difference would be of dropping them slightly angled to the horizon, so that their horizontal energy gets partially transformed to lift until they slow down and sink.

Why the hell would they need parachutes?? They would be dropped from couple of meters above the water..
Didn't you understand the idea? They need not be retrieved from the water - the water will recede during low tide.

The 250000 6th army at stalingrad was holding out for more than 2 months against 90 soviet divisions fully equipped with modern tanks and huge amounts of artillery.
During that time they were sustained by air supply only.
And the LW didn't have the option of dropping the cargo - the planes had to land on limiting airstrips which lowers the effectivity of the operation tenfold.
If you add my idea of fast dropping of supplies in the water and replace the 90 powerfull soviet divisions with whatever feeble forces the english had available you must see where the result would be...

Sorry, but an air supply campaign that is delivering less than the absolute minimum of food, ammo and other basic supplies is not sustaining an army.

I provided you with a valid example of an army fighting much stronger enemy and receiving tenfold less supply than I propose and still holding for 2 months. Can't you make the extrapolation alone?

And RAF bombing runs on the lines of grounded merchant ships? How about British land artillery?

While those would be obviously a problem they cannot sink the ships - becouse the ships are allready lying on the ground.
So the damage will be as much as that on the landed troops - it's a war after all - nobody said it's a walk in the park.

So we run aground in the high tide in order to get the ships as close to the shore as possible, then wait 6 hours for the low tide before we begin rolling off the heavy equipment? To paraphrase Col. Kilgore from Apocalypse now - "The tide doesn't go out for 6 hours. You want to wait here for 6 hours?"

While waiting the ships would be constantly unloading supplies with the numerous boats and some small barges brought along.

b) The close the fight of these is to the german bases, the longer the Me109E's can be in the air and the less shot down RAF pilots can be retrieved.
c) The close the fight of these is to the german bases, the less use would RAF have of their Radars.

This still does not address how these Me109s will be escorting Junkers over the invasion beaches and Dorners over the RAF bases at the same time. They can't, so one mission will have to either go without adequate escorts, and risk heavy losses (which makes follow up mission less effective, which makes the enemy stronger, which means heavier casualties) or not at all.

As I allready explained - when you take the RAF fighters off their inland duty you make it easier for the LW attacks there.
It's a trade off situation, in which the closer the fight is to the German air bases the more balance is tipped in LW favor.

So from the above you must understand that attacking 30 minute sorties would be at most an act of desparation for the RAF in such situation. It would lead to much quicker disaster than saving their breath and keeping the fighter squadrons close to their inland bases.

There certainly will be desperation, but I think you are attributing it to the wrong side. Once the Germans realize that, after depositing an army group on a foreign shore with their backs to the sea (and no way to get them out now that all of the transports that brought them in had their front hulls blown off by prepositioned explosives) that their air resupply campaign will never deliver the necessary amount of tonnage to sustain them, then desperation will really kick in.

This is a nice phrasing, but the numbers I provided show otherwise.
While the sacrificing of the ships is somewhat unortodox, if you ask any good chess player he'll tell you that big sacrifices can bring big victories...