Operation Sealion - creative approach

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LWD
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#61

Post by LWD » 11 Dec 2006, 02:55

kalpazanin wrote:...
The canisters will be trown at shallow angle at much less height and speed - 2-4 meter at speeds of 100 km/h
Therefore they'll bounce on the surface until their kinetic energy is consumed by friction and then sink.
2 to 4 meters This has got to be near the stall speed of some of these planes at least when loaded and any mistake at all and you loose the plane. Besides that 100 km/h makes them sitting ducks to anything that can shoot at them
There will not be a single 2 ton container, but 2 containers each 1 ton or 4 containers of 500 kg. (usefull if Stukas get involved)
And how many 155 rounds can you get in one of these containers? How about spare tires or track?
The pilots need not more training than to land a plane on airfield.
They do not need to hit moving ships with the containers - only to drop those in the approximate target area, close to the surface - that's much easier than landing a plane!
Are you serious? This is a nightmare flight profile.
As to the tide quiestion - there must be around 2 meter water above the low tide - which means from 80% to 50% of the tide cycle time will be availabe for dropping(depending on spring /neap tide).
After several hours the tide will recede and the containers will be collectable by foot. - Obviously the collectors could use a some wheel carts or horse carriages or even a trucks to pick them up faster.
The collection could be done at night to make it diffcult for RN to interfere.
If it's a sand beach maybe. If it's mud lots of luck. And even if they sink they won't necessarly be where they dropped as the undertow may well roll them further out to sea in fact the physics would tend to indicate this is the most likely event.

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LWD
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#62

Post by LWD » 11 Dec 2006, 03:07

kalpazanin wrote:...
http://images.google.com/imgres?imgurl= ... g%26sa%3DN
Above is a link to ship beached in camber - not far from where part of the invasion would have taken place.
And it was almost asuredly stranded by storm surge. Not by normal tides.
As I previously described , the Ju 52 could lift up to 3 tons of weight, if fuel tanks are not completely full. Since the sorties are extremely short this is not a problem.
Therefore 2 tons is well bellow their max capacity.
It's not just about weight it's about configuration. If they are the same size as bombs or torpedos they may not work well for carrying supplies. If you radically change the size or configuration the plane may have problems carrying them.
The tidal difference during spring tide is 18-20 feet in the channel - more than enough for the 4100 ton ship to get beached and completely out of the water.
Here is one link :
http://www.doversolo.com/channelqs.htm
That's in the channel and not on the South coast of England. The channel tends to concentrate things. Also if you go for max tides it will increase the current through the channel which will slow your transports.
As to the containers - there is hardly any design neccessary - a 1 sm thick and 40 sm widex 2meter long steel pipe closed by lids, would be more than enough.
Kilometers of such pipes were produced by german steel industry every day.
Regarding the testing, 84 days would be more than enough for tests and production.
Tests should be secretly done of course...
sm? Not familiar with that measurement.


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#63

Post by JonS » 11 Dec 2006, 03:10

Kingfish wrote: Brilliant!
Oh pish. He did say - right at the start - that this was a 'creative' approach to SEALION. Clearly fact-based analysis has no place in this thread ;)

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#64

Post by Polynikes » 11 Dec 2006, 03:13

kalpazanin wrote:
The loading of the equipment will take days. The loadinng of the troops will take hours.
Knowing something's 'up' gives them nothing. They must know what and when.
Firstly I would dispute that 200,000 men can embark on a fleet of 100 merchant ships in mere hours.
Secondly, as you've already admitted, the equipment loading would take days so presumably the troops would be part of that, therefore the embarkation of the troops takes DAYS also.
Thirdly, the loading of tanks and troops onto ships tells the British "what", it also tells them "when" as you can't keep troops bottled up on ships for too long. What the British need to know is "where".
The British go on to full invasion alert which reduces reaction time and removes the element of surprise.
Excuse me?
A Liberty ship could carry 440 tanks.
I'am talking of ships with comparable tonnage (1/3) carrying only 10 tanks. Where exactly is the problem??
Where are the troops are supposed to be once boarded. On deck? In the hold?

It's not a weight issue, have you any idea how much space 2,000 fully equipped troops take?
If you bother to read my posts you should notice that the controlled explosion is supposed to happen after the troops leave the ship.
Actually that wasn't clear but OK...
Problem now is two-fold:

1. How to get 2,000 men & their personal equipment/weapons off the merchant ship - in darkness. Not something I'd want to do - do you envisage scrambler nets to the beach/water?

2. Even if the ships is evacuated of men (which would take many, many hours), I find the idea of exploding charges inside the ship to allow the removal of tanks, trucks, artillery etc something of a fantasy.
Have you got any real life example to base this on?
Of course if the dis-embarkation of the 2,000 troops takes so many hours (it would take longer to get off than to get on without the aid of port facilities) - the tide would be back in.
Lastly, merchant ships aren't built like ferries, their holds are broken into compartments. So blowing off the bow doesn't help the rear holds. Now you could cut holes into the bulkheads but I'm not sure how that would affect the ship's sea-worthiness.
That may be true if the merchant hits a reef by chance.
When doing it in a planned manner the ship will be placed in carefully studied beaches with the right slope.
The effect would be not much different than placing the ship in dry dock.
Again have you got any real-life examples to base this idea on? I have tried to think of a way you could do this and can't. A 15,000 ton merchant man would require a hell of a lot of support to remain upright on a beach. IMO it would roll on to its side before you had a chance to stabilize it (even if you could figure out a way to install a system powerful enough to stabilize it on an uneven beach).

Beaching a ship is not an exact science and a lot can go wrong. At night (even with a full moon - that's not guaranteed by the way) I would say there's no way at all you can hit a precise spot.

Steering into a dry dock and beaching a ship is not the same thing.
If you disagree with my basic idea completely without providing any logical argument then there is nothing much I can discuss with you...
Actually I love the creative nature of you idea...it's the kind of sceme that Hitler might have suggested to his horrified generals.

I just don't think it's workable though - your ships wouldn'tbe easily unloadable and the men they unloaded would be in no condition to fight.

Furthermore, they would not be able to be supplied in the manner you suggest.

An "escalade" isn't actually a bad idea in itself.
I've head it suggested that the Germans could've engineered a "Dunkirk" in reverse. Send over as many men as possible in small boats immediately after the Dunkirk battle.

Couple this with a massive para drop to flood the area around the SE England ports in the hope of taking one or two by surprise and hold it while reinforcemetns arrive by sea into the ports.
Last edited by Polynikes on 11 Dec 2006, 03:24, edited 1 time in total.

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#65

Post by LWD » 11 Dec 2006, 03:14

kalpazanin wrote:
Andy H wrote:
but with my proposed changes to the Sealion the invasion fleet will be on the english shore long before the Home fleet arrives from Scapa Flow
The Home Fleet was not the main RN defence against the propose invasion, but the destroyers & cruisers in the southern ports and the vessels of the Auxillary Patrol.

Regards

Andy H
I agree.
According to commonly available data (as I previously posted) those consisted of 3 light cruisers 17 destroyers + various MTB boats.
Against those the KM had 10 Destroyers + 25 u-boats + 18 S-boats + some patrol boats.
With the help of some port mining by LW prior to the invasion I'd say it's a close fight..
In any case the KM will be completely capable of keeping this force busy until the ships hit the beaches.
The Home fleet probably wouldn't be sent right away. When it was clear that most of the KM was at sea they would likely be sent to make sure almost none of it made it home. After that they can shell the invasion forces and shut down the resupply effort. As for the KM being capbable of keeping the RN away from the transports, how??? The would have to be spread out to cover all the transports which means they have almost no chance of stopping any of the cruisers and very little of stopping the DD's. By this point in time the British were pretty good at clearing mines and even if the RN doesn't intercept the transports before they beach they and their contents will still be very vulnerable for several hours if not days after they beach. The LW had a much more favorable situation at Crete and they weren't able to stop the RN from intercepting the Germans.

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#66

Post by LWD » 11 Dec 2006, 03:19

Kingfish wrote:...
So, now we have a pilot who doesn't really need any specialized training, flying an airplane not designed for the mission, who then will strap upwards of 4 heavy and bulky cannisters full of artillery shell or POL underneath his wings, takes this airplane into hostile airspace, fly over the waves at no more than 4 meters high, look for water that is no more than 2 meters deep above the lowtide mark, then drop his payload (which BTW will bounce several times - I bet they''ll love that part), fly home and repeat this another 10 times a day.
...
Brilliant!
I seam to recall a number of US bombers getting knocked down by their own bombs that bounced and they weren't flying anywhere near as low. At the elevations we're discussing here a minor hangup in the release mechansim can mean the conainter hitting the water while still attached to the plane.

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#67

Post by Brian Ross » 11 Dec 2006, 03:31

kalpazanin wrote: For every bullet shot there were 20 produced?!?
Or more. Think about this. According to this, each Germany Rifle Coy, consisted of:
http://www.nuav.net/organiz.html wrote: Rifle Company
Strength 201 men. (2 officers/21 NCO´s)
Had 3 platoons and 1 staff platoon.

Weapons:
16 Sub-machine guns
12 Machine Guns
44 Pistols
130 Rifles
3 Anti-tank rifles
3 50 m.m Mortars
Each Bn. had three Rifle Coys and a HMG Coy. The HMG Coy consisted of:
http://www.nuav.net/organiz.html wrote: SMG Company
Strength |77 men. Had 3 SMG platoons(each w/ 4 SMG´s) and
1 Mortar Platoon (6 x 81 m.m Mortars)
This produces a fighting total of:
48 x SMGs
36 x LMGs
132 x Pistols
390 x Rifles
9 x AT Rifle
9 x 50mm Mort.
12 x MMG
6 x 81mm Mort.

Now, assuming that your weapons are engaged in a firefight, lasting one minute
you would require:
28,800 rds of LMG ammunition
3900 rds of Rifle ammunition
660 rds of Pistol ammunition
24000 rds of SMG ammunition
27 rds of AT rifle ammunition
180 rds of 50mm mortar ammunition
9600 rds of MMG ammunition
90 rounds of 81mm mortar ammunition

Now, that is only a very rough calculation. In fact I'd half that allowing for the inability of all weapons to fire in the battalion.

Now, think about that over a whole day's fighting, just for that battalion, for a week, for a month and so on. Now, then also then start thinking about resupplying that ammunition. Think about how much must be held at brigade, divisional and corps levels depots for those organisaitons in toto, not just for this mythical battalion. Then think even further back, how much must be produced daily, to replace the losses, both from usage at the front but also enemy action and negligence by your own forces. Then you'll see why I suggested 20 was a conservative number.

Your figure of 100 tons a day, is what is moving "in the pipeline", not what is produced. Do you think Germany stopped producing ammunition after a day's worth had been created? Of course bloody not, they kept on producing as much as they could, as fast as they could (when they felt necessary - there is some debate about that, I admit), for as long as they could. They kept pumping in war materiale' at the start of the supply pipeline and pulling it out as fast at the other end. An operation on the scale of Sealion would have required supplies in the tens of thousands of tons, each day, to be delivered to the front, across the channel. The Germans were completely incapable of doing that. Like you, they'd have been grasping at straws and finding nothing they could have done would have supplied sufficient for the needs of the units that made it ashore simply because they couldn't even move that much across the channel once their lines were interdicted by the British. They were ill equipped to mount such an operation and even more ill equipped to even sustain it.

You ask for hard references. Unfortunately, I don't have any to hand but I do have a brain, which I must suggest is a great deal more than you are presently displaying in your flight of fancy, mate. I can do simple maths and I know what sort of usage rates are realistic in wartime, for infantry units involved in hard fighting and you've failed dismally to take them into account. I am also very aware of the rates which must be realistically supplied to maintain a force in battle. So, perhaps instead of insulting particularly my and the rest of our's intelligence when you suggest someone whas failed to live up to your standards as far as references go, you should consider that their personal experience may well provide information that you don't have available to you.

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#68

Post by Andy H » 11 Dec 2006, 04:06

Creative doesn't mean ASB=Alien Space Bats for a concept, and some of the ideas floating in this are already thereabouts.

Regards

Andy H

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#69

Post by LWD » 11 Dec 2006, 04:16

Mention has also been made of the transports defending themselves and the Kormoran has been held up as an example. She is a very poor analog for how the transports will react. The Kormoran had a naval crew and naval artillery on naval mounts. Lets look at some of what that measn. First of all the guns. The German 150mm field gun had a range of under 10,000 yards and fired a 90 lb he shell. Source:
http://www.wwiivehicles.com/germany/for ... pperFH.htm
Compared to the Naval gun which had a 100 lb shell that traveled over 20,000 yards.
http://www.navweaps.com/Weapons/WNGER_59-45_skc16.htm
The naval mounts are designed to be used on ship and allow a reasonable amount of traverse as well as absorbing the recoil. The artillery would have to be fixed on deck. If it's rigidly attached then it's going to be difficult to train much if not the rolling ship will move it around. The Kormarand would have also had range finders suitable for naval action. The land artillery on board the transports is going to have open sites which are probably less than useful over a few thousand yards. If you are going to fire the guns from on deck you are also going to need a ammo supply closse by which increases the vulnerability of the transport. Then there is the question of whether or not the deck and restraints will take the shock of firing.

So no strapping your artillery on to the deck of transports is not going to add much to their self defence capablity unless MTB's decide to machine gun them and even then I'd put my bets on the MTBs.

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#70

Post by Lkefct » 11 Dec 2006, 04:23

kalpazanin wrote:
Lkefct wrote: I'm ignoring them because they are not terribly realistic. You are using some handwaving and genrealizations towish away the real probelms in the invasion.
My dear Lkefct,
I would gladly answer any new questions that you ask.
Those above were allready answered by me several times. I cannot constantly repeat myself - please read my previous posts.
I hope you are not offended...
You never answered ANY of hem. You used handwaving to ignore them.

If you beach the ships how are you going to make sure the ships stay upright?

How are you going to move the supplies from the other holds (other then the first?
How are you going to make sure that you down badly twist and destroy the floors?

How are you going to be sue that you have enough of similar builds of ships that you don't spend all your time doing structural work to make sure that blowing a hole in the side of your ships works?

Most importantly if it was this easy why is it that no one else ever tried this before?

How are you going to replace all the half tracks and tanks from the first wave. Many will get flooded and sawmped in the landing ships, plus British artillery and AT guns. How are the infantry going to have any firepower to advance. If it is man vs man in small arms type of combat, the British will win due to being on the defensive and their modest amount of material is likely to be overwhelming?

In his defense, they really don't need 100 tons of supplies a day. Much of the material needed is artillery ammo, fodder and fuel (and lubricants). The germans will not be bringing thier artillery, tanks, or any other motor vehicles in large numbers, so they can save that. They can't bring horses. Without trucks and horses, they can't move any useful artillery around, so they can actually save a lot of that weight. Of course that eliminates most of the firepower and mobility of a division, but ...........

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#71

Post by Kingfish » 11 Dec 2006, 05:18

Lkefct wrote:Most importantly if it was this easy why is it that no one else ever tried this before?
Well, they had...

Image

The S.S. River Clyde was run aground at "V" Beach on the 25th April, 1915. Note the square section removed along the hull of the ship. This is where the Dublin Fusiliers disembarked to run up the Beach. Many were drowned and killed when just disembarking.

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#72

Post by JonS » 11 Dec 2006, 05:52

Lkefct wrote:If you beach the ships how are you going to make sure the ships stay upright?
As much as I'm loath to lend the Moon Bat Theory of Amphibious Operations (MBTAO) any credibility, ships falling over after beaching doesn't actally seem to be a problem. Witness all the ships that are deliberately run aground on that beach in India for wrecking/dismantling.

Also this photo, from Vietnam, 1975: Ship on beach (fourth photo from the bottom)

As someone on another forum pointed out; the plural of 'anecdote' is not 'data'. However, I can't find a single photo of a ship that has run aground in semi-controlled fashion (ie, not thrown up on the shore in a storm) which has fallen over, or even taken on much of a lean.

Regards
Jon


(totally unrelated)

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The devil is in the details...

#73

Post by kalpazanin » 11 Dec 2006, 13:58

Kingfish wrote:
Lkefct wrote:Most importantly if it was this easy why is it that no one else ever tried this before?
Well, they had...

Image

The S.S. River Clyde was run aground at "V" Beach on the 25th April, 1915. Note the square section removed along the hull of the ship. This is where the Dublin Fusiliers disembarked to run up the Beach. Many were drowned and killed when just disembarking.
1) That operation was done in the Mediterrerean sea - there are practically NO TIDES there.
2) There was only a single ship and it was beached directly under the gun range of a castle...

Any idea can be transformed to catastrophy if one tries hard enough...

However, I must thank you , since this info shows undeniably that 2000 troops can be transported by 4000 ton merchant. (Someone here was seriously doubting that...)

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#74

Post by kalpazanin » 11 Dec 2006, 15:26

JonS wrote:
Lkefct wrote:If you beach the ships how are you going to make sure the ships stay upright?
As much as I'm loath to lend the Moon Bat Theory of Amphibious Operations (MBTAO) any credibility, ships falling over after beaching doesn't actally seem to be a problem. Witness all the ships that are deliberately run aground on that beach in India for wrecking/dismantling.

Also this photo, from Vietnam, 1975: Ship on beach (fourth photo from the bottom)

As someone on another forum pointed out; the plural of 'anecdote' is not 'data'. However, I can't find a single photo of a ship that has run aground in semi-controlled fashion (ie, not thrown up on the shore in a storm) which has fallen over, or even taken on much of a lean.

Regards
Jon


(totally unrelated)
Hello John,
Allthough I cannot understand why you loath the idea :?
I still must thank you for the honest approach.

The reason that those ships stay upright is becouse while the tide slowly recedes, part of the ship's weight is placed on the small area of the keel.
The wet sand cannot withstand such high pressure and slowly gives in until the keel gets burried in it.
Try to lean on your heels in a wet sand and you'll see the result pretty fast.

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Re: The devil is in the details...

#75

Post by LWD » 11 Dec 2006, 15:27

kalpazanin wrote:...
However, I must thank you , since this info shows undeniably that 2000 troops can be transported by 4000 ton merchant. (Someone here was seriously doubting that...)
The problem was not transporting 2,000 men. It was transporting 2,000 men and a bunch of armored vehicles and artillery. This is at least circumstantial evidence that the latter wouldn't work ohterwise they would have put more men on her or used a smaller ship.

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