Operation Sea Lion (1974 Sandhurst Wargame)

I do not have my copy of the Sandhurst wargames book with me but IIRC the Umpires moved the goal posts as much as possible to aid the Sea mammal as much as possible and the result was still a disaster for the Germans.

And this is exactly why the Unmentionable Sea Mammal would have been a disaster for the Germans.

In the Sandhurst wargame of the proposed invasion, the umpires practically bent over backwards to help the Germans out in pretty much every way they could and it still ended up being a German loss.

And, looking at the Wiki page on the 1974 wargame, it's pretty clear to me they made a major tactical decision that, in the real world of September, 1940, the British Admiralty would almost certainly NOT have done.

Which was to not use the Royal Navy to its maximum effect to stop the invasion forces from getting across the Channel unmolested.

The wargame assumed the RN would be sending its ships down from Scotland and would not have gotten there by the time of the invasion and therefore basically assuming the RN would essentially sit out the first part of the battle.

Does anyone really think the Royal Navy would have basically sat back and said, "Alright, Jerry, we'll have a hot toddy of Earl Grey while we wait for you get to our shores and then we'll get around to trying to stop you. Good day, old chaps!"

Uh, no. I don't.

They would have thrown everything they could at the invasion forces and almost certainly the invasion would have died in the waters of the Channel.

I myself doubt very much that even a single German soldier would have reached England and almost certainly any soldiers who did get across would have either been captured or killed within a few hours or maybe a day or two at most.

Which is why the 1974 wargame came to the conclusion that it would have been a disaster for the Germans.
 
Its a cunning plan my lord. The more Germans that get stuck on the beach the faster they will starve. Then it is a quick hop back over the Channel to finish off the Hun and back in time for kippers.
 
I suppose if they are really confident they can pocket them around the beaches they could let them land then wipe out the second wave of barges. Wipe out half a million or more German troops.

Would need a huge appetite for risk though.
 
Having just read this thread I am going to have to do a search to see if there is actually a way that the Germans can WIN the sea mammal (I mean, POD 1901???) lol.

That aside however, I have noticed that everybody is discussing the initial wave and not much else. Say that this wave does indeed land successfully and manages to establish sa a oh i don't know, 20mile beach head from the invasion beaches by the end of Day 1 (Wavehandium here I know!). How in the name of Zeus's buthole do they resupply the army???

The Allies had more than a few serious issues doing that in 1944 with DEDICATED SHIPS and with NAVAL AND AIR SUPREMACY. How will the Germans do it with neither and well, no ships by the looks?

Simple. They won't.

That is why the invasion will fail more than anything. They can't resupply. Any army landing is therefore irevellent. They are lost unless you can resupply. Period.
 
That is why the invasion will fail more than anything. They can't resupply. Any army landing is therefore irevellent. They are lost unless you can resupply. Period.

Exactly right. No matter how many troops get ashore they can only last as long as the water and food they carry lasts. They will be drinking from puddles and chewing their belts within 48 hours. The British Army needs to do no more than hold the line and let the big blue hammer go to work in the Channel. In fact exactly what generations before planned to do hold the line and wait for the bodies to wash ashore.
 
[snip]You seem to assume that the all those German paper ships are all going to be available, ready for action, formed up on the other side of the channel or steaming around in the channel running interference with no one noticing, as if by magic?

Moreover you are assuming there's going to be crew available for all that when the plan involved stripping out crews to help with crewing the barges (and even then they were going to have to press gang the occupied territories for additional crew and they were still going to be undermanned after doing that).

And many of these men are NOT navy but civilian. The panic that will ensue when the firing starts will be considerable...
 
For those of you not familier with the geography of East Sussex and Kent beyond HOI2 to HOI4 in particular their coast lines here is a good map showing the areas that are cliffs and marshes etc

So from Littlehampton to Brighton you have shingle beaches and in many areas off shore sandbanks back by hills etc

Then between Brighton and Eastborne you have high cliffs - broken only by the Ouse at Newhaven and the Cuckmere estury which is mostly mashland

Then between Eastborne and Bexhill you have the Pevensy Levels - more marshlands with very little in teh way of any infrastructure (Raods etc) beyond then more Cliffs Bexhill to Hastings and beyond before you get the Romney marshes and then Dover with its cliffs

Most of this coastline would not support any inland movement beyond light infantry and manpacked equipment

The few ports are small and likely to have been sabotaged making their very small logistic value even less so an invading force that managed to get shore is unable to be able to supply itself

Image-1.jpg
 
For those of you not familier with the geography of East Sussex and Kent beyond HOI2 to HOI4 in particular their coast lines here is a good map showing the areas that are cliffs and marshes etc

So from Littlehampton to Brighton you have shingle beaches and in many areas off shore sandbanks back by hills etc

Then between Brighton and Eastborne you have high cliffs - broken only by the Ouse at Newhaven and the Cuckmere estury which is mostly mashland

Then between Eastborne and Bexhill you have the Pevensy Levels - more marshlands with very little in teh way of any infrastructure (Raods etc) beyond then more Cliffs Bexhill to Hastings and beyond before you get the Romney marshes and then Dover with its cliffs

Most of this coastline would not support any inland movement beyond light infantry and manpacked equipment

The few ports are small and likely to have been sabotaged making their very small logistic value even less so an invading force that managed to get shore is unable to be able to supply itself

Image-1.jpg
"I can see my home from here"
 
Could be, but frankly if they need to get closer they will. 500 yards will be fine to hit these slow moving boats with MG, auto cannon or what have you

If the ships being attacked are unarmed then an optimal engagement range might be something like 200 yards. If the ships being attacked have strong armament (20mm and up), then the optimal range might be 500 yards or more.

Traditionally in battle you don't send out low draft / low board riverboats into the channel to fight destroyers. Such boats can be stopped, swamped, sunk or set adrift, by far more things than a direct hit by a 11" cannon. Just being there is likely enough to sink or stop these ships...<snip>

The Sandhurst naval results against the second wave were 1,500 barges sunk by 75 warships with no warships sunk by air attack. That's a tempo of 20 barges sunk per warship. Is that a realistic result for an unarmed invasion fleet with no escorts or air support? Probably. Is that realistic for an armed invasion fleet with escorts and heavy air support? Probably not.

Apparent target size will be largely irrelevant as they'll get as close as they need to and will likely be using the weapons that are better suited to hitting small targets anyway, speed (or lack of it in the case of the barges) however is important only huh you never address that.

Case 1. A DD vs. 10 barques in daylight and none of the barques are armed.
Case 2. A DD vs. 10 ships in daylight armed with: 6 x 20mm, 4x40mm, 4x50mm, 4x75mm.

Question - what is the optimal engagement range for the destroyer in Case 1? What is the optimal engagement range for the DD in Case 2?
 
The Sandhurst naval results against the second wave were 1,500 barges sunk by 75 warships with no warships sunk by air attack. That's a tempo of 20 barges sunk per warship. Is that a realistic result for an unarmed invasion fleet with no escorts or air support? Probably. Is that realistic for an armed invasion fleet with escorts and heavy air support? Probably not.
Is it unrealistic? Likely. But I note you're rather keen to ignore the unrealistic aspects of the exercise that favoured the Germans...

Does it matter that much? When even your very optimistic (for the Germans...) figures imply something like a 10% sinking rate for German sealift on the first day, and that's ignoring the likely toll of vessels badly damaged but not sunk and the inevitable disruption and chaos among German forces caused by the RN rampage (see: transports turning for home and troops landing in penny-packets at the wrong locations). Well, the strangulation of the German invasion force takes a week rather than two days; there's a larger fraction of PoWs and smaller fraction of drownings within the German losses and more RN light forces get mauled or sunk due to the longer time period.

It does bugger all to change the overall picture of a mauled, disorganized, scattered and poorly supplied German force pinned near the beaches and eventually forced to surrender.
 
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One of the factors not yet mentioned is the severe disruption of the German economy caused by the failed invasion. Transport by the various barges along the river systems represented a significant proportion of goods movement, especially for bulk cargoes. The loss of a large number of river barges and coastal transports is going to impact the ability of the German economy to produce anything. To the extent that those lost vessels are going to be replaced, or repaired if damaged, that is going to put a further strain on limited resources. Steel, shipyards, engines, etc used for rebuilding this vital transport link are not going to be used for tanks, U-boats and so forth.
 
If the ships being attacked are unarmed then an optimal engagement range might be something like 200 yards. If the ships being attacked have strong armament (20mm and up), then the optimal range might be 500 yards or more.



Barges with gun tied onto them are not strongly armed, 20mm is not strongly armed anyway


The Sandhurst naval results against the second wave were 1,500 barges sunk by 75 warships with no warships sunk by air attack. That's a tempo of 20 barges sunk per warship. Is that a realistic result for an unarmed invasion fleet with no escorts or air support? Probably. Is that realistic for an armed invasion fleet with escorts and heavy air support? Probably not.

What armed invasion fleet (see above) armed doesn't just mean has guns, are they usable guns, are they usable when you rolling on seas you not designed for at 2-4knts and firing at actual warships travelling at 15-20knts.

Also what escorts, what heavy air support. or rather you seem to have forgotten the if there is the LW around then there is likely the RAF around as well, similarly if you now talking about the KM running escort than well so will the RN larger ships.


Also you forgetting or ignoring that you talking a bout a flotilla travelling 2-4knts, this impacts on everything, an actual KM warship trying to escort this will either be travelling at 2-4km itself (and thus a sitting duck) or will have to be running loops around the flotilla at higher speed. Similarly the LW will have to escort the same slow moving fleet which means they will have to loiter over the channel for 2 days (or rather they will in fact stagger themselves to provide continuous cover thus diluting thier force and as per the ships above will be sitting ducks)

(also didn't the sandhurst war games just have the RN not turn up or turn up very late?)


Case 1. A DD vs. 10 barques in daylight and none of the barques are armed.
Case 2. A DD vs. 10 ships in daylight armed with: 6 x 20mm, 4x40mm, 4x50mm, 4x75mm.

Question - what is the optimal engagement range for the destroyer in Case 1? What is the optimal engagement range for the DD in Case 2?


case 1. Barques are a lot faster and generally more seaworthy than river barges again you keep ignoring this, it is huge factor, so not relevent to sealion

case 2 "ships"means a lot of efferent things and that the most important thing, 10 barges that for some reason have 6 x 20mm, 4x40mm, 4x50mm, 4x75mm. attached to them is very much not the same thing as 10 actual sea going ships like converted trawlers with 6 x 20mm, 4x40mm, 4x50mm, 4x75mm.


(Also a barque is a rigged ship, not sure that's what you mean , however if the German can some get enough of these and enough crew they might be better than the river barges :)!

You keep doing the same thing over and over and ignore the whole contest so a river bat with a 75mm bolted to it becomes a combat ship with 75mm mounting. The LW are now in attendance en masses, but there's now RAF

and most of all you ignore, and ignore and ignore that this barge flotilla is crawling along at 2-4 knt totally at the mercy of seas they're not fit for.
 
You do not have to sink a barge to mission kill it, in a channel crossing invasion. Delay the barge and miss the tide and your planning has just gone to hell in a hand basket. The confusion caused by even a single Armed trawler attacking a group of barges (many on double tows) would be devastating, Tows lost, Tows tangled, canted tows and tugs sunk are just the starters. I do not think most people are really able to give a coherent judgement on the out come of such an attack, I have sailed the channel since child hood and have towed vessels across it and I shudder at the ease with which people dismiss the effect of gunfire in the night on a convoy of towed barges (I have never served in the military or seen combat so I have no personal knowledge of the effects of being under fire) and the disarray that would cause.
 

marathag

Banned
(Also a barque is a rigged ship, not sure that's what you mean , however if the German can some get enough of these and enough crew they might be better than the river barges :)!
.

Around 20 years ago on either SMN or SHWI on Usenet, just after the term ASB was first coined, I put forth that the Germans would have been better off training their men to row and to build modern Longships for the Invasion of SE England than to try barges.

Non-strategic materials, low visibility on the transit over, and use on the rivers after landing were the high points.

Other highlights was even after being run over by HMS Enraged, the wood then becomes floatsam, giving the survivors something to hang on to.
 
The RN will be throwing depth charges about as well, there will be a lot of dead fish in the channel that day, as well as quite a lot of bodies.

The effect of lobbing a few depth charges among barges full of men is pretty gruesome, shock injuries even on barges that don't get sunk will be pretty horrific.
 
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