Operation Sea Lion (1974 Sandhurst Wargame)

[DaveBC]

@DaveBC

Yes, I think you sum up the Nazis dilemma well. I've supported the notion of a Unilateral Declaration of Peace, or at least a ceasefire.

However, even if the British acknowledge the ceasefire, they will most likely simply use the time to rebuild the army, repair ships and complete new ones, shift forces to Egypt etc. Plus they will be free to use shipping through the Mediterranean and, without the Battle of the Atlantic, will not be so dependent on US supplied. Arms and ammunition yes, but not raw materials, fuel or food. So scarce USD conserved.

As you say, once the military and civil service have analysed the situation, they will simply allow the ceasefire to end. Having improved their position substantially.

And if they don't acknowledge the ceasefire but carry on bombing raids on Germany, how long can Hitler turn the other cheek? About 48 hours?

In which case, back to the dilemma.

You're right that there are serious reasons to think this strategy would fail. On the flip side, there are risks to any approach. The only three that anyone has credibly floated for Germany in 1940 are, so far as I can see, Sea Lion, Barbarossa, or a unilateral ceasefire. Maybe you can do the first two together, and maybe you can do the second two together. You certainly can't have all three.

Now Glenn has made a valiant effort at making a case for the first of those, but has failed utterly.

The real world has pronounced its judgement on the second.

Which leaves a diplomatic route. Cue the howls of protests that I am being unrealistic, no doubt, but if someone wants a credible answer to "how does Germany win the war in 1940," I think that's the best one there is.

 

[Garrison]

It never occurred to me that the British would risk losing the war by stripping their reserves to try a counterattack at Isle of Wight. How big a counterattack would they risk, and how long to prepare it?

You mean you didn't think this was likely despite the number of times you've been told that the British sent large numbers of troops and tanks to the Middle East at the height of the invasion scare? But I suppose like so many inconvenient facts you've chosen to forget about that.

 

[hipper]

It never occurred to me that the British would risk losing the war by stripping their reserves to try a counterattack at Isle of Wight. How big a counterattack would they risk, and how long to prepare it?

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10’000 well-armed men within six hours, or twice that number within twelve hours. according to churchill


Mr. Churchill's views lent only partial support to the Vice-Chiefs of Staff. In his estimation the strength of the defences on a given stretch of coast must be measured, not by the number of troops immediately available, but by the number of hours within which strong counter-attacks could be delivered.70 It ought, in his opinion, to be possible to concentrate 10,000 well-armed men within six hours, or twice that number within twelve hours, at any point where the enemy had come ashore in strength

 

[Glenn239]

Presumably because you want to hold it against a counter-attack.

I mean, if you want to let the British just capture all the FJs that were put into the sausage machine in the IoW, you can just leave them there with no support.

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Describe the proposed counterattack in more detail. Let's assume the garrison has surrendered and the FJ holds the north shore, with heavy air activity and some over the beach logistics occurring.

Less kind people than me would suggest you're just trying to wank Britain by giving them cheap victories in 1940, of course - a massacre of the German paratroops in 1940 means Crete gets held, no threat to Malta and so on.

Crete had something like 40,000 troops. From what I've read, IOW had maybe 4,000 in July 1940, of considerably lower quality. I don't think that strength of garrison could hold. I think it would collapse.

 

[DaveBC]

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Describe the proposed counterattack in more detail. Let's assume the garrison has surrendered and the FJ holds the north shore, with heavy air activity and some over the beach logistics occurring.



Crete had something like 40,000 troops. From what I've read, IOW had maybe 4,000 in July 1940, of considerably lower quality. I don't think that strength of garrison could hold. I think it would collapse.

If the FJ are getting new supplies onto the Isle of Wight via beaches on its northern shore, that puts the German supply convoys in the Solent.

Why not just sail them straight up the Thames and take London head-on?

 

[nbcman]

Minefields and coastal artillery will be factors in the defense of invasion transport close to shore on the French side of the Channel.

Not for your proposed IOW-USM. There would be no coastal artillery and minimal minefields at the Dover Strait in mid-July as you've postulated as the first German guns were not installed until late July / early August.

In terms of capacity attrition, the RN would be the most serious threat.

Only if the German invasion transport comes out of port. The RAF is the most serious threat if they stay in port.

The RAF scored its successes in ports choked with invasion transport.

The RAF was following Sutton's Law: They attacked the ports because that is where the invasion transport was located.

Coastal artillery cannot hit a fast moving destroyer at 15,000 yards. At 5,000 yards, different story.

Why would a DD captain sail that close to coastal artillery mounted on the French shore unless it is to chase a fleeing German ship? The RN can wait until the German ships are further from shore and then bang away at them. And what German coastal artillery would protect the IOW-USM 'fast transports' that would be sailing from Cherbourg which is far from the German Dover Strait guns that haven't been installed yet?

Bye.

 

[alfredtuomi]

without landing craft (barges)this is your beach logistics.....add waves.....add tidal current......add swells that have just crossed the atlantic
see a problem here?ocean

 

[Glenn239]

10’000 well-armed men within six hours, or twice that number within twelve hours. according to churchill


Mr. Churchill's views lent only partial support to the Vice-Chiefs of Staff. In his estimation the strength of the defences on a given stretch of coast must be measured, not by the number of troops immediately available, but by the number of hours within which strong counter-attacks could be delivered.70 It ought, in his opinion, to be possible to concentrate 10,000 well-armed men within six hours, or twice that number within twelve hours, at any point where the enemy had come ashore in strength

So if Isle of Wight wasn't an island, then 10,000 men in 12 hours. But Isle of Wight is an island, so what sort of reinforcements with their heavy weapons can get across in 24 hours?

 

[Glenn239]

Not for your proposed IOW-USM. There would be no coastal artillery and minimal minefields at the Dover Strait in mid-July as you've postulated as the first German guns were not installed until late July / early August.

Right, but the July 1940 attack uses faster transports, not barges, and is much smaller in size, so isn't taking 24 hours to form up on the French side. When he talked about the RN attacking invasion shipping forming up on the French side, he's talking the big invasion in September, actual Sealion. Why would a DD commander pile his squadron into minefields covered by coastal artillery and most of the entire German air force, just to attack invasion shipping that can be attacked much more safely as it comes north and leaves the French shore behind?

Only if the German invasion transport comes out of port. The RAF is the most serious threat if they stay in port.

Agreed, but once the invasion is at sea, the RN is by far and away the primary danger. If the RN wasn't a factor, if the RN didn't exist, and the defenses were the RAF and British army only, the chances for Sealion would have been much, much higher.

Why would a DD captain sail that close to coastal artillery mounted on the French shore unless it is to chase a fleeing German ship? The RN can wait until the German ships are further from shore and then bang away at them. And what German coastal artillery would protect the IOW-USM 'fast transports' that would be sailing from Cherbourg which is far from the German Dover Strait guns that haven't been installed yet?

A DD captain wouldn't go over to the French side to attack invasion shipping. They'd wait until it moved into the Channel.

In terms of installing coastal defenses at Cherbourg, I'm not certain what calibre of shore batteries could be emplaced in a month's time - maybe 6"?

 

[Post]

So if Isle of Wight wasn't an island, then 10,000 men in 12 hours. But Isle of Wight is an island, so what sort of reinforcements with their heavy weapons can get across in 24 hours?

I'm gonna go with more than the Germans. Since the British have an actual navy and acces to a port.

 

[Post]

Crete had something like 40,000 troops. From what I've read, IOW had maybe 4,000 in July 1940, of considerably lower quality. I don't think that strength of garrison could hold. I think it would collapse.

But at Crete the Germans had airsuperiority (and almost airsupremacy) and not half the RN was less than a day sailing away. And there were little coastal fortifications.

And even at Crete the German attack nearly failed.

 

[vizzer]

But the British have a barge with guns on it at the IoW which according to earlier posts will easily be able to see off any German ships which approach

 

[Glenn239]

Huh, I thought all you needed to do with give a guy a parachute and lo! suddenly you have 60,000 Germans in the Isle of Wight.

A JU-52 or HE-111 could deliver about 15 troops per sortie. So, to put 60,000 troops on the ground, and if there are, say, 400 transports available in the air fleet, then that's a requirement of 10 trips per plane. Do you suppose a plane could make 10 trips in, say, a 10 day period delivering troops, if the necessary forward airfields were available? I figured if the airfields were available, maybe about 2 trips per plane per day, one with troops, the other with supplies. The big problem is the RAF - to preserve the transport fleet, the supply has to happen at night as much as possible. If it's in the day, the RAF will rapidly attrite the fleet.

 

[alfredtuomi]

So if Isle of Wight wasn't an island, then 10,000 men in 12 hours. But Isle of Wight is an island, so what sort of reinforcements with their heavy weapons can get across in 24 hours?

ps shanklin
ps merstone
ps portsdown
ps southsea
ps sandown
ps ryde
ps whippingham
ps duchess of norfolk
mv vecta
just to name a few and all but one were based in portsmouth

so probably 10,000 every 4 hours.

 

[Deleted member 94680]

Describe the proposed counterattack in more detail. Let's assume the garrison has surrendered and the FJ holds the north shore, with heavy air activity and some over the beach logistics occurring.

No, let’s have you explain in realistic terms exactly how this fantasy situation would come about.

Crete had something like 40,000 troops. From what I've read, IOW had maybe 4,000 in July 1940, of considerably lower quality. I don't think that strength of garrison could hold. I think it would collapse.

Why would it “collapse” in the face of scattered FJ drops with no form of support, heavy weapons, vehicles or reinforcements apparent?

 

[alfredtuomi]

A JU-52 or HE-111 could deliver about 15 troops per sortie. So, to put 60,000 troops on the ground, and if there are, say, 400 transports available in the air fleet, then that's a requirement of 10 trips per plane. Do you suppose a plane could make 10 trips in, say, a 10 day period delivering troops, if the necessary forward airfields were available? I figured if the airfields were available, maybe about 2 trips per plane per day, one with troops, the other with supplies. The big problem is the RAF - to preserve the transport fleet, the supply has to happen at night as much as possible. If it's in the day, the RAF will rapidly attrite the fleet.

so you want to land how many planes per hour on a rough landing strip in the dark under continuous artillery fire and level bombing?

 

[Post]

A JU-52 or HE-111 could deliver about 15 troops per sortie. So, to put 60,000 troops on the ground, and if there are, say, 400 transports available in the air fleet, then that's a requirement of 10 trips per plane. Do you suppose a plane could make 10 trips in, say, a 10 day period delivering troops, if the necessary forward airfields were available? I figured if the airfields were available, maybe about 2 trips per plane per day, one with troops, the other with supplies. The big problem is the RAF - to preserve the transport fleet, the supply has to happen at night as much as possible. If it's in the day, the RAF will rapidly attrite the fleet.

As I pointed out to you before, the poorly defended dutch airfields near The Hague attrited the fleet very much. I'm quite sure the British can do better, since they've got a RN which can bombard the airfields at night (not fun landing and unloading while being bomdarded, I think). And they will know where to hit, because there will be spotters, and the fields will have some lighting, because landing and unloading in the dark will be really difficult. Apart from that they're not gonna make two runs in a night per plane. That's just impossible, with loading and unloading.

 

[Alanith]

A JU-52 or HE-111 could deliver about 15 troops per sortie. So, to put 60,000 troops on the ground, and if there are, say, 400 transports available in the air fleet, then that's a requirement of 10 trips per plane. Do you suppose a plane could make 10 trips in, say, a 10 day period delivering troops, if the necessary forward airfields were available? I figured if the airfields were available, maybe about 2 trips per plane per day, one with troops, the other with supplies. The big problem is the RAF - to preserve the transport fleet, the supply has to happen at night as much as possible. If it's in the day, the RAF will rapidly attrite the fleet.

If you're admitting that the RAF is capable of rapid attrition to HE-111's used in a transport role, then logic follows they're also capable of doing to same to them in a medium bomber role, like say, trying to force the RN out of an intensely heavily defended location such as Portsmouth. You will be further forced to husband a not insignificant portion of the medium bomber fleet for use as improvised air transports, meaning they're not available for other tasks. This suggests that the operation will be forced to take place with the RN still present in force, which therefore means they will be lobbing 4.7 to 15 and 16 inch HE shells into landing zones identified or suspected in daylight every hour of the night, even if they've been identified by such a simple method as a farmer who, upon reaching the mainland, promptly bitches up a storm about the Germans tearing down his stone walls and hedgerows in HIS fields!

 

[alfredtuomi]

A JU-52 or HE-111 could deliver about 15 troops per sortie. So, to put 60,000 troops on the ground, and if there are, say, 400 transports available in the air fleet, then that's a requirement of 10 trips per plane. Do you suppose a plane could make 10 trips in, say, a 10 day period delivering troops, if the necessary forward airfields were available? I figured if the airfields were available, maybe about 2 trips per plane per day, one with troops, the other with supplies. The big problem is the RAF - to preserve the transport fleet, the supply has to happen at night as much as possible. If it's in the day, the RAF will rapidly attrite the fleet.

it gets worse.you want to conduct 800 landings /unloadings/take offs in less than an 8 hour period of darkness.that would be a rate 60% greater than the berlin airlift which took two months to get to that tempo organized by major general tunner who ran the airlift into china over the himalayas.
really.

 

[Alanith]

it gets worse.you want to conduct 800 landings /unloadings/take offs in less than an 8 hour period of darkness.that would be a rate 60% greater than the berlin airlift which took two months to get to that tempo organized by major general tunner who ran the airlift into china over the himalayas.
really.

I'm also pretty sure I don't recall the part where the Soviets were incessantly shelling the grass fields the Berlin Airlift was using for its B-26's either.