There is no way to give a definitive answer on this one. There are a few things that you have to "take" into consideration:
And these actually do make a definitive answer!
a) The German economy was already streched by the current re-arming programing. If it focused on building better landing craft - or more planes, etc, then something had to give. While Germany didn't hit a war time economy until about 43, Hitler didn't do that to prevent internal dissent within Germany,
Mostly correct, see my post elsewhere about Iron/Steel and Engine shortages/hard production limits.
However, the bit about the Germans not going to a wartime economy until 1943 because Hitler didn't want to piss off the civilians is an old furphy, now widely discredited.
In fact, the reason why German production went up in 1943 was not so much that the Germans went to full wartime production (which they really didn't do till mid 1944), but because they hadn't planned for a war starting in 1939. They had planned for a war starting in 1943 or later, and they had devoted a chunk of their existing industrial capacity to expanding itself so that their overall capacity would be expanded from 43 on.
When war broke out in 1939, they had a choice ... keep with the plan, and soldier on with whatever production capacity they had, or ditch the plan, basically throwing away hundreds of millions of RM worth of incomplete expansion that would be ... wasted ... and which couldn't be caught up with later.
They chose to do the first ... keep with the plan. To manage this, and to keep the German civilians happy, they basically stripped the economies of the occupied countries bare to allow them to maintain wartime levels of expenditure on armaments etc. while also keeping civilian rationing less severe than it had to become later. In effect, the French, Dutch, Danish, Norwegian, Belgian, Polish etc. etc. civilians were rationed severely to keep the German civvies happy.
b) Any invasion across the North Sea has to assume that the British Navy is destroyed. After Norway, Germany simply didn't have navy to defend an assualt across the North Sea. And while the British Army was in bad shape, the British Navy - especially in the North Sea - would simply destroy any invasion fleet.
Indeed. The British Navy had so many vessels in the Home Fleet, Channel Command, and Northern Approaches command that there is no way the Kriegsmarine, even if it had not lost a single ship in Poland or Norway, could have faced it down, not even with the Luftwaffe.
The Home Fleet and Humber Force could have sortied south during the hours of darkness and slaughtered the landing craft and support craft (see why below) and been back far enough north for the Luftwaffe to only be able to attack them with unescorted bombers against the RAF providing top cover.
Note: The RN didn't even need to shoot at the landing craft the Germans had. The Rhine River barges they gathered for the op had such a low freeboard that anything over Sea State 2 (a light chop) and they'd be taking on water ... a high speed pass by a DD doing 33+ kts and they're swamped ... hello Davy Jones' locker!
c) There's major debate about whether the British would commit major capital ships - or many destroyers - into the English Channel to break up a German invasion. We don't know. But you would have to assume that the British wouldn't. If they did, drown baby drown.
Not really a major debate. Not much of a debate at all ... see above and below as to why it would have been a minimal risk, then consider ...
"It takes three years to build a ship; it takes three centuries to build a tradition. The Navy always supports the Army. The evacuation continues." Admiral ABC Cunningham, on the evacuation of Crete in the face of total German air supremacy (note especially the second and third sentences, which rarely get quoted).
There is no doubt at all that the RN would have sortied south, nor is there any doubt that they would have slaughtered the Kriegsmarine.
d) The German Air Force, in 1940 (and actually up till 43) simply did not preform well against naval units. Despite all its hype, the German Air Force didn't have the training, the right bombs, or the bomb sites to really attack naval units. So even with air superiority, the German Air Force would have had a problem defending the invasion fleet.
The German aerial torpedo was completely useless. So useless, in fact, that after 1940 they had to but *Italian* aerial torpedoes to use ... the Italian ones actually worked. The German ones almost universally porpoised (and missed) or broke up on hitting the water. As for the bombs, as you note, they were the wrong sort ... they bounced off even light armour or penetrated but didn't explode, largely, depending on which of the two basic wrong sorts they used.
As to training and equipment. Well. See. The Luftwaffe had *one* unit trained, sort of, in Aero-naval combat. But the aircraft it was equipped with and the weapons it had ... were piss poor ... and the training wasn't all that effective, either.
The aircraft? He-111 Torpedo Bombers. Floatplanes.
Against Spits and Hurricanes?
e) The German Army needed a broad front to land. The German Navy wanted as narrow a front as possible as it didn't have the resources to protect the fleet. Strategically, these two aims were NEVER reconcilled.
The Kriegsmarine planners were so frustrated by Army wishful thinking "planning" (almost as good, if not better, than Japanese wishful thinking wargaming of ops like Midway etc!) that, since they were forbidden by Hitler from actually explaining why what the Army wanted couldn't be done, could only resort to writing rude comments on the "planning" documents that were submitted to them.
As for the plans. Some of the more outstanding idiocies ...
* Landing Tanks by blowing the bows off the Rhine River barges that carried them, then, the tank totally sealed up with no escape tube, completely blind, and an air tube linking the engine to the surface, has to crawl ashore under water. Can one understand why the Kriegsmarine planners were writing rude comments?
* The River Barges, towed by Tugs, Fishing Trawlers and small Coasters, could barely manage 4-6 kts, and, for significant portions of the route they had to take, would have been sailing against a current that would have reduced this to 2-3 kts or less.
In fact, the units sailing from the nearest invasion ports required the best part of 24 hours to get from said ports to the destination beaches. The units sailing from the ports in the Low Countries required something more like 36 hours. One way.
Which means that, inevitably, they had to make a significant part of the journey in *broad daylight* ... with almost a literal handful of DDs and some E- and S- boats to "protect" then against the Home Fleet, Humber Force, Channel Force, Western Approaches Command and, probably, forces based in Gibraltar. Dozens and Dozens and Dozens and Dozens of DDs and light combatants, not including CLs, CAs, BCs, BBs and CVs ... and not mentioning the RAF.
Given that they have to make the journey there *and* back ... 24-36 hours *each way*, the barges would also sailing across one, possibly two, nights ... and that means that the RN will be able to sortie south, from behind RAF aircover, further north than the Luftwaffe can send fighters to escort the few bombers it has that, theoretically, could attack them ... if only their torpedoes and bombs actually *worked* ... slaughter the German landing craft by making 30+ kt high speed passes and swamping them if they run out of ammo, and, well, you get the picture.
* Oh. Did I mention that the German plan was to land "elements" of 9 (later 12) Divisons ... equal to around 3 (later 4) Divisions in the "first wave" ... across either a narrow or broad front, but, regardless, at three or more separate sites ... and, then, well ...
Reinforcements? Two to three *weeks* after the first landing! Yes. *W*e*e*k*s*. I kid you not. It's all in what passes for the "plan".
Oh, and that means *no resupply* for the same period. So, 3, maybe 4, divisions ... even as damaged and unprepared as the British Army is supposed to have been, and wasn't, when you examine it closely, it still had several fully trained, fully equipped, Divisions on hand, including a complete Armoured Division plus lots more partly equipped and partly trained units.
(Note: German Infantry Division = about 10000 men, give or take. UK Infantry Division = about 20,000 men, give or take. German Infantry Division = Foot and Horse Waggon transport. UK Army = 100% motorised)
* Panzers? No resupply = no fuel. Even if they landed 20-30 and they all managed to get ashore, they'd soon be out of fuel. Matildas can take them out, and, though there weren't many, there were enough to handle the few the Germans could hope to land in the first wave. The rest of the Brit armour was Bren Gun Carriers and MG armed light tanks, but they were better armour than most of the German bridgeheads would have had.
f) The German's never achieved air superiority. A given for the invasion.
And they needed Air *supremacy*. The Luftwaffe had to do three impossible things before Brekkie ...
* Defend the Kriegsmarine and Landing Craft from the RN and RAF, day and night.
* Defend the Wehrmacht beachheads against the RN, RAF and British Army, day and night.
* Act as Artillery for the Wehrmacht initial invasion forces, which were being landed with little artillery, less shells, and none of it heavy stuff.
The Luftwaffe, historically, was incapable of doing even one of the above, committing 100% of its available strength in attempts to do so, let alone all three simultaneously, all three requiring, individually and separately, a 100% effort from the whole Luftwaffe.
g) The final plans for Sea Lion have about 70K troops landing. And with a second follow up wave. This represents about 7 to 9 divisions depending on they're configured. While the British Army was in bad shape, it doesn't look like this could achieve a break out. And I can't believe tht the second wave would actually land.
Yep, around 3-4 Division equivalents over several separate beachheads, or perhaps 20-30,000 men in the first wave, with the second wave ... two to three weeks later.
h) The Germans would have to capture a major port in decent shape to get the supplies needed to the troops that landed. Sea and air supply without a major port in decent shape wouldn't provide the needed supplies (actually, only about 1/20th in a combat situation).
And the only major(ish) port in the landing area was Dover, which was, at best, a minor port incapable of meeting German requirements. The rest? The Cinque Ports? Silted up and capable, at best, of taking some fishing trawlers.
No one in the German High Command actually thought this would work.
The Kriegsmarine planners certainly didn't, see comments above about how they scrawled rude comments on the plans the Army submitted!
The Wehrmacht? There's some doubt. It seems as if they couldn't *really* have taken it seriously, but, on some levels, they seem to have done so ... more seriously than the Kriegsmarine, at least.
IMO, Best case - and I mean best case - the British let the first wave land and then seal off the landing. Worst case, you could see the majority or all sunk at sea.
And consider the flow on effects!
Hitler's rep for invincibility takes a nose dive! Even if he survives *this* time, a failure against Russia in 1941 would become much much more problematic
I just have a hard time seeing this operation as realistic even in the best of circumstances. And the Germans never achieved the best.
Yep. Agree 100% with *that*
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