Strategy Thread - BTR

[soeren01]

ORIGINAL: Dixie

What were the LW torpedo bombers like at that stage of the war? Surely Stukas and torpedo bombers would be a major factor in RN losses as regular bombing was rarely effective against a moving ship. The RN would have gone into action with or without RAF AS in an effort to stop the landings.

At that time of war german torpedos where still not very reliable. While the Torpedo planes made good attacks agains merchant shipping, succesfull attacks against naval ships where very rare. German air launched torpedo productio during this time was between 20 and 50 torpedos/month (have to look it up). In addition there where only very few aircrews qualified for airborne torpedo attacks as the navy could not train and the airforce would not train.

[HMSWarspite]

ORIGINAL: Dixie

What were the LW torpedo bombers like at that stage of the war? Surely Stukas and torpedo bombers would be a major factor in RN losses as regular bombing was rarely effective against a moving ship. The RN would have gone into action with or without RAF AS in an effort to stop the landings.

You also have to remember that the sort of RN forces most useful in defecting the invasion are destroyers and smaller. You would only need to get 2 or 3 DDs, or a half dozen MTB or something into the invasion barge fleet one night and the Germans would have had a very bad time. Do it 5 or 6 times in the first week, and the follow-up landings would look very vulnerable. If Churchill was prepared to sacrifice say 20 destroyers regardless, to attack the fleets (not being swayed by the 'we are lost - save the RN to send to Canada' naysayers), the invasion would have been very unlikely to succeed. A few days of bad weather would likely have the same effect. Of course, the loss of the DDs makes the sub war interesting later, but the loss of the barges on the Ge economy is also significant. The presige gained by the British in defeating an invasion might have off set the loss in ships. Certainly, Hitler loses his invincibility reputation well before late 1942 when he lost in in RL!

[Hard Sarge]

ORIGINAL: HMSWarspite

ORIGINAL: Dixie

What were the LW torpedo bombers like at that stage of the war? Surely Stukas and torpedo bombers would be a major factor in RN losses as regular bombing was rarely effective against a moving ship. The RN would have gone into action with or without RAF AS in an effort to stop the landings.

You also have to remember that the sort of RN forces most useful in defecting the invasion are destroyers and smaller. You would only need to get 2 or 3 DDs, or a half dozen MTB or something into the invasion barge fleet one night and the Germans would have had a very bad time. Do it 5 or 6 times in the first week, and the follow-up landings would look very vulnerable. If Churchill was prepared to sacrifice say 20 destroyers regardless, to attack the fleets (not being swayed by the 'we are lost - save the RN to send to Canada' naysayers), the invasion would have been very unlikely to succeed. A few days of bad weather would likely have the same effect. Of course, the loss of the DDs makes the sub war interesting later, but the loss of the barges on the Ge economy is also significant. The presige gained by the British in defeating an invasion might have off set the loss in ships. Certainly, Hitler loses his invincibility reputation well before late 1942 when he lost in in RL!

okay but again, if they get into the fleet during the night, every account is being based on the GE being stuck in the area at night and letting the RN in to wreak the landing

I still say, you wouldn't need to be at sea during the night, to have the landing

plus for the most part, it is a landing to take a few AFs, once the AFs are under control, the basic supplies would be airlifted in, the tanks would be sent in by ship/barge, and I still think the GE would be smart enough to know, that hey, we can cross and unload 3 tanks and then have to leave, if we don't want to be caught in the open

your gonna see the ships coming, so you know when they are going to get there

plus a landing in England in 1940 is not going to be on the same scale as the landing in France in 1944, and wouldn't need to be, so the shipping and troops and supplies are not going to be any where near as great, and as the GE have already proved in France, even Armor can live off the land

for anti ship, I think the Stuka would of been the main weapon of choice, it was a ship killer, as had already been seen, and the 88 was pretty good at it too

which will agree, that the 111 and 17 wouldn't really do much damage, once the ships were seen, they could still be used to make them burn fuel and waste time dodgeing

[Banquet]

It's always an interesting discussion. Of course there are too many unknowns to know for sure what would have happened.

I think the only way Germany could have pushed the RAF back to North London was to continue their airfield raids. These were very effective. They tried and failed to win AS over Southern England by fighting the RAF in the air. Had they pushed the RAF back to North of London by bombing the airfields, it would have given them an easier time over SE England but would NOT have given them AS. I see no reason why the RAF would be tied up escorting bombers. The important obective for the RAF would be to provide air cover for the Navy.

Although the Royal Navy had ordered it's big ships out off the Engish Channel, there were still plenty of smaller ships there that would be more than capable of destroying the German invasion ships. The home fleet was held back further north for precisely the purpose of engaging the invasion fleet, should it sail. The Royal Navy were scared of aircraft attack. During the invasion of Norway HMS Suffolk had been damaged by air attack and it made Britain wary of sending it's warships into air attack range. However, (with hindsight to what was to come in the Pacific) it actually showed the inefficiency of German planes to sink ships (33 sorties flown against Suffolk and still they couldn't sink her)

Suffolk was on her own and had no air cover. With that in mind what chance would Germany have had of sinking a major part of the Royal navy, with RAF air cover?

Peter Schenk's 'Invasion of England' shows German plans for getting troops to England. 3-4 days were required to get the first waves off the ships on average. And yes, the ships would be all nicely lined up during this time (German diagrams show them as such). It was such a delicate operation, with the tides dictating much of the schedule, that it's easy to believe it would have all gone wrong without any interference from Britain at all. Infact a dummy run in France had gone completely wrong. Had they got ashore one objective was to take Dover which would have made life easier for getting supplies across the channel) It's hard to see how this operation would not have turned into a complete disaster once the RN had arrived.

I Attach a picture of one of the planned invasion locations (Rottingdean I think) Over a hundred ships, many towing barges spending 3 days unloading an infantry division in this small gap!

I certainly wouldn't say the Germans were stupid but invading England was an entirely different proposition to the battles they had fought on mainland Europe.

[Hard Sarge]

sure, that is why we talk

yes, but you bring up Norway, why not Dunkirk ? the RAF couldn't protect the fleet there and they would be much closer, the Press made a big deal of the major air victory that the RAF had won, but the numbers show it was no where near a victory (the victory was the Navy and the small ships getting the troops home, but they paid a major price for it)

and again, that is what the writers say and think, the "plan" kept changeing though out the air battle, and no staff officer worth his rank, is going to make a real battle plan, that takes 3 days to off load a Div of men

and, again with my background, I can tell you it does not take days to offload a Div of men, it don't take days to load a Div of men, supplies and bulk can take major time, but most assault troops carry what they need, when they land, supply comes later (and remember a Marine Div is 2 to 3 times the size of a GE or GB Div back then)

I think the idea I am trying to get across, is most of these writers, back then, would also be telling you that the GE could not win a war against France, that they could not cross Lux, that they could not take Greece, and that they couldn't take Crete, in fact, they couldn't take Eben Eble (sorry spelling) that was a untakeable fort

if the GE do everything by the book, and according to how the RN expects them to mount a landing, it will fail, hands down, I don't believe if they were really planning on doing it, they would of done it by the book, as I say, alot of the BoB does not make it look like they were really fighting a battle to win

remember also, alot of the plans and reports we see today, were done by Naval Officers, who really didn't want to have to make a landing or to support one, so alot of there plans and time tables were done up, trying to show, it couldn't/shouldn't be done, once the Army Commanders started to get into it, they started making major changes to what was needed and what they could do

[Banquet]

I agree it wouldn't have taken 3 days to get off the bulk of the fighting men.. but to get all the equipment and supplies ashore was stated as 3 days in the German plans at the time. They hoped for an overall turnaround of 6 days (2 days to load the division, 3 days to unload and, presumably, one day sailing back and forth)

Remember we're not talking about a US Marine division here. US Marines are trained and equipped for seaborne invasions. German infantry divisions were not, and did not have the equipment. The troops would have to transfer to the barges from other ships. As far as I know the barges would then have to be towed by tugboat into the shore. Getting armour ashore was even worse. I've seen photo's of planks of wood being arranged off the ships to get tanks onto land.

This was for the first wave of 9 divisions. The 2nd wave, (approx 15 more, including armour) would then have to been shipped across and then the whole lot would have had to be supplied by sea. I can't see how airlifted supplies are going to keep 25 divisions in enough supplies for offensive operations. I think they would have had massive problems supplying these units from across the channel even without interference from British aircraft and warships.

You're right about Dunkirk, the airforce did have moderate success attacking shipping in that operation. Although the fact that 250,000 plus men managed to escape in boats indicates they weren't that successful. And, these were ships operating close to land, exactly the situation the German navy would be faced with while invading. I say German Navy but, apart from the barges, steamships, tugs and motorboats there were half a dozen destroyers and possibly 3 light cruisers allocated to the operation. That's all the KM had. And submarines of course. I just can't see that force keeping the RN out of the Channel for the weeks required to win a land war.

Stuka's were reasonably effective against ships but without torpedo's doing serious damage to the larger warships in the RN was certainly not guaranteed.. especially, as mentioned earlier, they'd been withdrawn from Bob due to high losses. As long as the RAF could get fighters to cover the navy.. I can't see how the Stuka's could have operated.

To be honest I find it hard to believe the German high command ever had any real intention of launching the operation. It was more likely a feint to keep Britain on the back foot and possibly to force a peace deal. If it hadn't been Churchill in power at the time, it might have worked in that regard?

[sprior]

The timing of the landings for the Germans, as later for the allies, was dictated by the tides. The German craft were designed to be beached on a falling tide to allow the boat to dry out and the troops disembark. Thus a prahm had to wait for the tide to turn and rise again before it was floated off. So, you can't just wait until it "gets dark" to land, you have to wait until the tide is ebbing too, and as that only happens twice a day (unless you're somewhere wierd like Southampton), then your landing time is severely limited. This also led to the Germans building their beach obstacles in the wrong place, above the low water line.

The allies landed on a rising tide so the LC could immediately pull off the beach to make room for more and to refill and return.

[SMK-at-work]

oo oo.....sealion talk....!!!!
 
ther are a few things to remember - Park was completely prepared to pull FC back "behind London" if required - and his loss tolerance for doing so was actually quite low - FC never fell below 600 operational hurricanes and Spitfires IIRC - plus it always had at least 200 in reserve and was making them at 400/month at the time.  the LW was only making about 200 Me-109's, started with a small superiority in numbers, but ended September with only 280 serviceable!
 
Sealion requied 3 days to offload the 1st wave - and then those same ships had to return to the continent to load the 2nd wave - there was no question of them only being off the English coast for a day to offload - they would have had to anchor there for 3 days and 2 nights.
 
the LW only had 1 stafflen of experimental torpedo bombers at the time, and little experience attacking shipping - te great naval sinkings in hte Med weer a few months away still and required some improvement in dive-bombing techniques and equipment - specifically armour piercing bombs for armoured taqrgets like carriers, cruisers, etc.
 
The Kriegsmarine was also minscule - IIRC they could assemble about 20-25 Destroyers and torpedo boats, a handful of cruisers, and 1 pre-dreadnought battleship used for gunnery training that was going to be beached and used as a battery!  The RN in home waters outnumbered them about 3:1 in destroyers and 4:1 in cruisers.  The German submarine fleet was fairly small - by using all their trainign boats with poorly trained crews they got up to about 40.....the Brits had about the same number, but all were better boats than the Type II's.
 
All in all it's a shame that Sealion wasn't attempted......because it would probably have shortened the war considerably by costing Germany a good portion of its early war veteran infantry and internal transport.
 
 

[Banquet]

Completely agree SMK. Germany was using pretty much every ship/boat/barge it had as well. Any losses couldn't be replaced. And, as Warspite said earlier, the loss of barges would have hampered the economy quite badly. I believe even just collecting all the barges in French ports caused quite some disruption to the economy.

[Hortlund]

What part of "the ships does not have to be fully loaded" do you guys not understand?

[fochinell]

yes, but you bring up Norway, why not Dunkirk ?

Yes, an excellent example of the Luftwaffe being unable to interdict RN forces effectively - even when they had destroyers tied up and stationary in Dunkirk. This is revealing for all those who assume the LW had a magic answer to the Home Fleet appearing in the Channel, perhaps even more so than what the RN did off Crete in circumstances where the LW had AS - which they didn't have over the Channel coast of England. [:D]

I think the idea I am trying to get across, is most of these writers, back then, would also be telling you that the GE could not win a war against France, that they could not cross Lux, that they could not take Greece, and that they couldn't take Crete, in fact, they couldn't take Eben Eble (sorry spelling) that was a untakeable fort

Sure. But the historical reality is that a leader who was prepared to gamble against the advice of his army when attacking Scandanavia, France, Russia and was even prepared to declare war against the USA when he didn't have to, still thought twice about invading Britain. The key here is the *naval* equation, not the military one.

if the GE do everything by the book, and according to how the RN expects them to mount a landing, it will fail, hands down, I don't believe if they were really planning on doing it, they would of done it by the book, as I say, alot of the BoB does not make it look like they were really fighting a battle to win

The nature of the Sealion is known history, and relying upon towed barges to mount a large-scale amphbious invasion against prepared defences wasn't tried by the allies, who spent a lot of time and resources working out how to do such things.

The Germans didn't invade Britain in 1940 for valid reasons. But the BoB was an expensive demonstration of the fact that the Germans had never thought seriously about how to force a British capitulation by air power and sea power alone. The losses they took indicate it was a serious attempt, however.

[SMK-at-work]

ORIGINAL: Panzerjaeger Hortlund

What part of "the ships does not have to be fully loaded" do you guys not understand?

The bit where the Germans were planning on loading their ships up to the gun'ls because they didn't have and couldn't GET enough shipping.

Look the plans for Sealion are reasonably well known - you can say "could have...should have...would have..." all you like, but what they planned for was what they planned for......and they only had the shipping that they could get....which WAS NOT ENOUGH for their ideal landing. they didn't have enough large ships - they didn't even have enough tows for the mass of unpowered barges they weer going to use.

Had they 3 or 4 times as much shipping then fine - things might have been different....but they didn't...and it wasn't.

I think the idea I am trying to get across, is most of these writers, back then, would also be telling you that the GE could not win a war against France, that they could not cross Lux, that they could not take Greece, and that they couldn't take Crete, in fact, they couldn't take Eben Eble (sorry spelling) that was a untakeable fort

Actually everyone thought that Germany COULD defeat France.....but they didn't expect it to take so little time, and they did expect the Germans to come through the Ardennes...that's why there were troops there - they "just" didn't expect them to come sthough in such force.....I don't know anyone who thought that Germany couldn't take Greece - where did you get that from??

And the Allied commander on Crete expected the German attack would have every chance of succeeding ...he had wanted to destroy the airfields, but his commanders thought they would prove more useful to the allies and decided that the invasion must be defeated since they knew all about it from Ultra....but of course to defeat an invasion you actually still need to take measures against it....not merely know about it!!

so there y'go - you are wrong on every one of those points!!

And we know the reasons why conventional wisdom at the time failed the defeated sides. And none of it applies to sealion.

[Hard Sarge]

ORIGINAL: SMK-at-work

ORIGINAL: Panzerjaeger Hortlund

What part of "the ships does not have to be fully loaded" do you guys not understand?

The bit where the Germans were planning on loading their ships up to the gun'ls because they didn't have and couldn't GET enough shipping.

Look the plans for Sealion are reasonably well known - you can say "could have...should have...would have..." all you like, but what they planned for was what they planned for......and they only had the shipping that they could get....which WAS NOT ENOUGH for their ideal landing. they didn't have enough large ships - they didn't even have enough tows for the mass of unpowered barges they weer going to use.

yes, they are well know, and they were done by Naval people who didn't want or plan on it ever happening, so it made it much HARDer then it had to be, to get everyone else to agree with them, that they shouldn't do it


Had they 3 or 4 times as much shipping then fine - things might have been different....but they didn't...and it wasn't.

I think the idea I am trying to get across, is most of these writers, back then, would also be telling you that the GE could not win a war against France, that they could not cross Lux, that they could not take Greece, and that they couldn't take Crete, in fact, they couldn't take Eben Eble (sorry spelling) that was a untakeable fort

Actually everyone thought that Germany COULD defeat France.....but they didn't expect it to take so little time, and they did expect the Germans to come through the Ardennes...that's why there were troops there - they "just" didn't expect them to come sthough in such force.....I don't know anyone who thought that Germany couldn't take Greece - where did you get that from??

Actually No, most of the people didn't think they could defeat France, the size of there Army and the number of Tanks and troops they had, they were not expected to lose the war

they expected them to come though there ? I guess that is why most of the French and English rushed into the north, all of there plans were to stop the Germens before they got into French lands

And the Allied commander on Crete expected the German attack would have every chance of succeeding ...he had wanted to destroy the airfields, but his commanders thought they would prove more useful to the allies and decided that the invasion must be defeated since they knew all about it from Ultra....but of course to defeat an invasion you actually still need to take measures against it....not merely know about it!!

they didn't expect them to be able to take Crete by air, and it was the same deal, with the Royal Navy in the Med, the Germens would never be able to land enough troops on Crete "by" sea to take it (which as part of the landing force, found out, was pretty much true)


so there y'go - you are wrong on every one of those points!!

all, I am trying to do is give you experts something to talk about, and one of the easiest ways is to say or ask if the Germens could of won Sealion

And we know the reasons why conventional wisdom at the time failed the defeated sides. And none of it applies to sealion.

[decaro]

ORIGINAL: Terminus
Well, they were following it pretty well, right up until the point when they stopped...[:D]

If memory still serves me, the Germans were successfully targeting southern RAF airfields daily, and the RAF was feeling the strain of this constant barrage.

But after a German bomber(s) accidently hit London during a night raid, the Brits retaliated in kind, to which Hitler replied, "Two can play at that game" and sent the Luftwaffle directly against the English populace by bombing major Brit cities. This new "plan" gave the RAF in the south enough time to repair their airfields and get back into the fight.

Of course, I don't expect BoB&BtR to have an algorithm for this!

[Banquet]

ORIGINAL: Hard Sarge


all, I am trying to do is give you experts something to talk about, and one of the easiest ways is to say or ask if the Germens could of won Sealion

[:D] Can't argue with that!

[SMK-at-work]

yes, they are well know, and they were done by Naval people who didn't want or plan on it ever happening, so it made it much HARDer then it had to be, to get everyone else to agree with them, that they shouldn't do it

Tough - they were their plans, and they used all the available shipping - to get less than a full load they either had to find shipping that wasn't available, or drastically cut back on the initial wave - it was going to be 3 divisions landing over 3 days - you want it to land in 1 day - fine - let's make it 1 division.....oops...not much of an invasion any more.....

Actually No, most of the people didn't think they could defeat France, the size of there Army and the number of Tanks and troops they had, they were not expected to lose the war

The Germans thought they could, and the allies were keenly aware of the possibility - that's why they looked at all sorts of plans to try to counter German intentions.

Of course they failed.

No one on the allied side actually knew the precise strength of the German army, so your comment about the number of tanks and troops is strange.

they expected them to come though there ? I guess that is why most of the French and English rushed into the north, all of there plans were to stop the Germens before they got into French lands

No - most English and French forces rushed north because that's where they expected the majority of the German forces to attack in a 1940 version of the Schliefflen plan. However they were aware of the route through the Ardennes and put what they thought was enough troops to cover it against the attacks they expected to happen there. French light amour and motorised Belgian infantry were advancing into the Ardennes when they met the Panzers.....but lacked sufficient anti-tank strength to be able to do much.

Even after the Germans had passed the Ardennes they still had to cross the Meuse....the French had prepared defences at Sedan - a deep fortified defensive line manned by a fortress division and the 55th infantry division - the French fully expected an attack there, BUT only after the Germans had built up enough infantry force - which they expected them to do by the 20th of May because of the traffic congestion in the Ardennes - indeed the Germans had planned on the same date!!

The French accordingly ordered their reserve divisions to that sector, but they were too slow - the Luftwaffe pounded the rear areas of the 55th divisions positions and when they broke through the front sectors after some heavy fighting the positions set-up to defeat them were already demoralised and/or destroyed.

So it is completely false to say the French didn't expect an attack through the Ardennes....they did expect exactly that, and they prepared for it. They just got it wrong.

they didn't expect them to be able to take Crete by air, and it was the same deal, with the Royal Navy in the Med, the Germens would never be able to land enough troops on Crete "by" sea to take it (which as part of the landing force, found out, was pretty much true)

You are correct about what the British high command thought, but you didn't read what I wrote - the commander ON THE GROUND in Crete did expect an airborne assault, and id expect to have a hard time of it....poor translation of Ultra lead him to think there would also be a seaborne component at the first assault, and this expectation remained for some time, reducing the forces available to counter-attack the airborne troops.

In fact the Germans did try to send troops by sea........and they WERE caught by the RN on hte night of hte 21 May and virtually every ship was sunk....it was only a supply convoy essentially - carrying ammo and support units, but that's what a small RN force of about 6 ships could do in 1 night.

all, I am trying to do is give you experts something to talk about, and one of the easiest ways is to say or ask if the Germens could of won Sealion

Yep - you asked, and you were answered.....and then you argued about the answers. Inspring discussoin is great, but yuo can't claim to be only seeking discussion once you enter the argument as well!!

[Hard Sarge]

Yep - you asked, and you were answered.....and then you argued about the answers. Inspring discussoin is great, but yuo can't claim to be only seeking discussion once you enter the argument as well!!

why ? I can't enter a discussion that is started ? I can't reply to any of the statements that are made with my own, right or wrong or made up, to keep the discussion going ?

[Hortlund]

ORIGINAL: SMK-at-work
Tough - they were their plans, and they used all the available shipping - to get less than a full load they either had to find shipping that wasn't available, or drastically cut back on the initial wave - it was going to be 3 divisions landing over 3 days - you want it to land in 1 day - fine - let's make it 1 division.....oops...not much of an invasion any more.....

Meh, say what you will about the Germans, but they were pretty good at adapting to new circumstances and changing plans on the fly. So a staff-officer made a plan that called for the ships to lay offshore and take three days to unload, and all sorts of sillyness. Big deal. That plan would not have survived even into the final preparations.

Cut back on the initial wave like you say. Instead of landing 3 divisions during three days, land a single regiment at night and have that regiment take a small port suitable for normal unloading operations. Suddenly you have cut down on offloading time from three days to three hours. Have paratroopers (before Crete, we can play with at least two divisions of those) land during that same night in blocking positions outside that port. Use the port to unload troops, instead of pulling them ashore on barges. Feel like one port is not enough? Too easy to disrupt unloading operations by air attacks? Take two. You have the units for it, and the opposition consists of home-guards. Heck, take three, or why not even five. Like I said, you can easily put two airborne divisions on the ground during that night, and you can land at least one regiment per target.

But no...instead you want to sit there and play out ludicrous scenarios where the entire German merchant marine is supposed to lay offshore for three days unloading infantry into barges that can barely float, pull those barges to shore at 3 knots and whatnot. its just silly.

[otisabuser2]

OK, I'm in...........[;)]

SMK is quite right. The German Sealion plan is well known. Whatever strange theories anyone may have about them being a bluff, ruse or otherwise are nothing but speculation only. The plan was highly detailed and subject of heated debate between German army and Navy. Unusual for a bluff don't you think ? However bad the plan may have been, they were stuck with it. The planners were not morons. Trouble is Hitler wanted it done, whatever, and they had to do the best they could to follow his orders under the circumstances. This was the plan they WERE going to use until Sealion was cancelled.

The lack of shipping and type of shipping ie huge numbers of unpowered river barges, were the key limitations. The use of these was what would cause the German fleet to be at sea and vunerable for so long. They were not necessarily just waiting off shore for 3 days to unload ( they'd probably sink ). This is journey time. This flotilla would have to load up and queue to emerge from their harbours in Europe and chug across the sandbanks, minefields and tides of the English Channel at speeds that would have embarrased William the Conquerer and his Normans. Oh, and then turn for shore at the correct place and somehow beach.

They had no Landing ships, amphibious assault craft, hovercraft or ospreys. Large ships may have been quicker than barges, but unable to get near enough to the beaches alone. Heavily armed soldiers can not swim.

They did not have the option of landing 2 divisions of paratroopers, because they did not have this. Nor the transports required to drop this number.

The British had more than Home Guards manning the key positions. The ports and harbours were defended. The British planners were not morons either.

The Royal Navy was at this time sucessfully operating destroyers nightly in the Channel. The Luftwaffe was unable to stop them.

That the Royal Navy would have been unwilling to risk their ships to defend the UK may need some evidence. The losses they were willing to take to defend/evacuate more minor places like Crete and defend Singapore suggest otherwise.

regards Otis

[Hortlund]

Basically what you are saying is this. "If the Germans had done a Sealion in a completely retarded fashion, they would have failed". On that I agree.
 
What I am arguing is that if the Germans did another variant of Sealion, they could very possibly have pulled it off.
 
As for the two airborne units, they had the units, and they had the transports. Not enough to lift them all in one go, but thats the neat thing with transports, you can use them more than once. Gliders and transports for the assault, then transports for the reinforcements.
 
And as for the transports. Bigger ships can unload in ports and other harbors. Smaller ships can be used for the initial assault. Barges can safely be left back in France.