Defeating Invasion Fleets

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Re: Defeating Invasion Fleets

Post by gebhk » 12 Feb 2023 11:04

With respect, it seems gentlemen you are trying to create rules while bypassing the fundamental one: which is that whoever has the greatest power available once the landing has taken place, will win and I think Peter89 has it. Because of this no one in their right mind will undertake an opposed landing unless they are sure of everwhelmong power at their disposal - and that usually means sufficient backup to ensure that even if you lose a very large chunk of your landing force in the run-up to the beach, you still end up with enough of a superiority on the ground to carry the day. For this reason I don't think citing historical examples is much use because they will inevitably not be balanced. And for this reason, throughout WW2, the defenders have debated the best tactics: fight at sea? On the beach? Inland? And all to little avail because they had lost strategically before the operation even began. In short, if you don't have the power to defeat the invader at sea, you most likely don't have the power to defeat him on land and vice versa. Probably the best you can hope for is a stalemate as at Gallipoli.

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Re: Defeating Invasion Fleets

Post by Richard Anderson » 12 Feb 2023 17:21

Carl Schwamberger wrote:
12 Feb 2023 06:36
Operation RESERVIST was certainly defeated. Technically 50% of the ships were lost & near half the landing force killed or captured. But tiny samples like that may not be good data to use.
Carl, RESERVIST was a very tiny part of TORCH and not an "invasion fleet". It consisted of a rump infantry battalion and two aging patrol vessels both of which were sunk, so 100% losses there unless you include the two motor launches (offhand I don't recall if they were lost as well). So yes, a very tiny sample.
Have to take a look at the details of the amphib side of the Crete operation. I can't remember how many soldiers crossed the beach during the battle, if any. At least one transport flotilla lost heavily and was turned back.
Yes, all the Crete invasion force's seaborne landings were turned away. The first seaborne reinforcement landed on 28 May.
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Re: Defeating Invasion Fleets

Post by Carl Schwamberger » 12 Feb 2023 19:23

Heres a few amphib landings that were canceled after the naval forces took losses. In some cases the fleet was clearly defeated, in others the canceling admirals were claiming victory.

Yes, all the Crete invasion force's seaborne landings were turned away. The first seaborne reinforcement landed on 28 May.

The first Wake landing attempt was aborted when US aircraft and cannon started sinking the invasion fleets ships. It was a small flotillia and just 2-3 ships damaged or sunk amounted to crippling the attack before the soldiers even got into their Daihatsu landing craft. I'd have to review the details to understand what percentage of the flotillia was sunk or put out of action. It may have bee as high as 40%.


The Coral Sea battle occured when the covering force for a series of related landings battled with the US fleet. The Tulagi occupation went ahead as planned & another minor occupation. The main event aimed at Port Morsby was canceled after the Japanese naval leaders got nervous after thinking they had won a noteable naval victory. There was a US cruiser TF dodging about, suspected but unlocated & the Japanese admirals were not confident they could protect the amphib fleet. So the Milne Bay landing was postphoned. In this case one light carrier sunk, & the fleet carriers damaged, out of position, & too far away was enough to throw off the Japanese commanders.


Midway: Ive actually heard people argue the Japanese fleet was undefeated. I'll include it here any way since Yamaoto decided the loss of the carriers waived away some of the conditions required to execute the seizure of Midway atoll.


Operation MENACE is a bit ambiguous, or my understanding of the decisions is imperfect. Rereading the sequence of events I'd tenatively agree it was a defeat of the fleet. While DeGualles decision not to shed the blood of Frenchmen by Frenchmen was the withdrawl of the French landing force, the Brits did hang round with their fleet fighting on. Maybe if they had suppressed the defense then there would have been a second landing attempt.



Hers a few where the fleet took losses, but the landing operation went ahead.

At Balikipan US destroyers were able to attack the tranport fleet, Sinking four cargo ships of twelve present. But, unloading operations had progressed far enough this did not cripple the operation ashore.

Similarly at Sunda Strait four of the Japanese tranports were sunk, but the operation continued. However the Army commander of the invasion force did have to swim a bit before rescue.

At Guadalcanal most of the local surface covering force was destroyed, then the Japanese declared victory & departed leaving the amphib transports unmolested. The US Admirals passed on abandoning the operation & continued.


Guadalcanal was mentioned: That definitely included the destruction/defeat of the transport fleet. But, it was more in the nature of interdicting a transport or reinforcement operation rather than driving off a fleet carrying the assault force, or imeadiate follow up force. Maybe in grand stratigic or operational terms that was the defeat of a invasion fleet. I've seen that view used in a analysis of the Guadacanal battle. Certainly doesn't fit in tactical terms.

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Re: Defeating Invasion Fleets

Post by Richard Anderson » 12 Feb 2023 19:55

Carl Schwamberger wrote:
12 Feb 2023 19:23
The first Wake landing attempt was aborted when US aircraft and cannon started sinking the invasion fleets ships. It was a small flotillia and just 2-3 ships damaged or sunk amounted to crippling the attack before the soldiers even got into their Daihatsu landing craft. I'd have to review the details to understand what persentage of the flotillia was sunk or put out of action. It may have bee as high as 40%.
It was the hits the bombardment force took that led to the withdrawal well before the invasion force was even close to the islands.

As the five destroyers of 6th Destroyer Squadron closed the islands to begin the bombardment, Hayate blew up at c. 0452 after being hit by one or two 5"/51 rounds that set off her midships torpedoes and Yayoi was hit by a single 5"/51 round that did minor damage but killed 1 and wounded 17. At that point the decision was made to abort and it was afterwards at c. 0537 that Kisaragi was bombed and blew up and Tenryu and Tatsuta were strafed and slightly damaged.

So it was the loss of one and damage to another destroyer out of the six present that led to the withdrawal decision. At that point none of the three light cruisers, five patrol boats, two gunboats, two merchant cruisers, five fishing boats, and one sub tender that made up the rest of the invasion "fleet" had been touched.
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Re: Defeating Invasion Fleets

Post by T. A. Gardner » 12 Feb 2023 21:28

At Midway, assuming the Japanese have perfect intelligence on US ships, they'd know there are still two US carriers present with partial air wings aboard, a third on its way with some amount of replacement aircraft along with its own (Saratoga) and that the US could fly more aircraft from Hawaii to reinforce the islands themselves. Knowing that, I would think their own lack of airpower to reply with would force a withdrawal.

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Re: Defeating Invasion Fleets

Post by thaddeus_c » 13 Feb 2023 01:36

is there an example of a totally new weapon or tactic against an invasion?

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Re: Defeating Invasion Fleets

Post by Kingfish » 13 Feb 2023 03:21

thaddeus_c wrote:
13 Feb 2023 01:36
is there an example of a totally new weapon or tactic against an invasion?
Kamikazes
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Re: Defeating Invasion Fleets

Post by T. A. Gardner » 13 Feb 2023 04:30

thaddeus_c wrote:
13 Feb 2023 01:36
is there an example of a totally new weapon or tactic against an invasion?
Well, during WW 2, I'd say, yes, and no. The new weapon would or could have been the guided antiship missile / bomb. The Germans deployed two, as did the US. The German ones were Hs 293 and Fritz X. The US ones were Pelican and Bat.

What these did was allow the opposing air force to launch weapons with reasonable accuracy against ships from beyond their defensive range. Had the Japanese managed to build an Oka suicide missile with more range and a bit more speed, it could have been a devastating game changer.

The yes part is these things existed. The no part is they still had some serious limitations due to the state of technology at the time.

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Re: Defeating Invasion Fleets

Post by Peter89 » 13 Feb 2023 09:17

T. A. Gardner wrote:
13 Feb 2023 04:30
thaddeus_c wrote:
13 Feb 2023 01:36
is there an example of a totally new weapon or tactic against an invasion?
Well, during WW 2, I'd say, yes, and no. The new weapon would or could have been the guided antiship missile / bomb. The Germans deployed two, as did the US. The German ones were Hs 293 and Fritz X. The US ones were Pelican and Bat.

What these did was allow the opposing air force to launch weapons with reasonable accuracy against ships from beyond their defensive range. Had the Japanese managed to build an Oka suicide missile with more range and a bit more speed, it could have been a devastating game changer.

The yes part is these things existed. The no part is they still had some serious limitations due to the state of technology at the time.
Ehhh, but doesn't it lead us back to the question of the control of the air?

Because Hs 293 and Fritz X were only effective as long as you had the trained crews, the proper number of aircrafts and a relative safety for these aircrafts to carry out their missions. The Germans didn't have any of these at the later stages of the war, when amphibious invasions actually happened. If they had them, the invasions wouldn't even be started. For example, the Wallies gradually wore down the Axis air forces in Italy before they launched their landings. Then they gradually wore down the Luftwaffe over Western Europe and the Reich before they actually started D-Day.

The fact that there was a real chance of an invasion of Northwestern Europe before the destruction of the Luftwaffe and the Wehrmacht's reserves happened, is probably the most underestimated WI in this forum. (Although Douglas Porch argues convincingly how dangerous it was for the Allied victory.)
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Re: Defeating Invasion Fleets

Post by gebhk » 13 Feb 2023 12:23

Hi Thaddeus
is there an example of a totally new weapon or tactic against an invasion?
That is a very astute question. And the answer is no, because at its core, a landing is, in principle, a military assault/defence operation like any other, subject to the same rules and using the same classes of equipment (by that I mean that on land troops/equipment would be moved by train/truck, at sea on a ship; different equipment but the same job).

The attacker must (1) bring up sufficient resources to the jumping off point (2) advance into contact and breach the enemy line (3) bring up resources to maintain and exploit the breakthrough. If one of these stages 1-3 is stymied, whether in an amphibous operation or a land-based one, the outcome would be at best a tactical stalemate and the operation will fail to achieve its strategic aims. The defenders role is to achieve at least a stalemate by defeating at least one of the phases. In addition it can be argued that isolating the battlefield from enemy reinforcement/interference is another key stage in itself, although I would include it in stages 2-3 because, unlike the others, a failure of this stage does not automatically mean a failure of the entire operation.

And because the phases of an amphibious landing are the same as for any other operation, the tools for defeating these phases are taken from the same arsenal. Weapons for destroying ships involved in landing a force are the same as the weapons that would be used for fighting a sea battle and so on. The kamikaze or guided anti-shipping bomb is not a weapon for defeating landings - it is a weapon for sinking ships.

I guess where I am painfully heading for is that there is no magic method that is always the best method for defeating an amphibious invasion. The defender must stymie at least one of the phases of the operation, the attacker must succeed in all three. How this is planned with be different every time, just as it is in a land battle and just as in a land battle will depend on consideratiuons of the situation, terrain, the enemies strengths and wekanesses and one's own.

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Re: Defeating Invasion Fleets

Post by T. A. Gardner » 13 Feb 2023 19:34

Peter89 wrote:
13 Feb 2023 09:17
T. A. Gardner wrote:
13 Feb 2023 04:30
thaddeus_c wrote:
13 Feb 2023 01:36
is there an example of a totally new weapon or tactic against an invasion?
Well, during WW 2, I'd say, yes, and no. The new weapon would or could have been the guided antiship missile / bomb. The Germans deployed two, as did the US. The German ones were Hs 293 and Fritz X. The US ones were Pelican and Bat.

What these did was allow the opposing air force to launch weapons with reasonable accuracy against ships from beyond their defensive range. Had the Japanese managed to build an Oka suicide missile with more range and a bit more speed, it could have been a devastating game changer.

The yes part is these things existed. The no part is they still had some serious limitations due to the state of technology at the time.
Ehhh, but doesn't it lead us back to the question of the control of the air?

Because Hs 293 and Fritz X were only effective as long as you had the trained crews, the proper number of aircrafts and a relative safety for these aircrafts to carry out their missions. The Germans didn't have any of these at the later stages of the war, when amphibious invasions actually happened. If they had them, the invasions wouldn't even be started. For example, the Wallies gradually wore down the Axis air forces in Italy before they launched their landings. Then they gradually wore down the Luftwaffe over Western Europe and the Reich before they actually started D-Day.

The fact that there was a real chance of an invasion of Northwestern Europe before the destruction of the Luftwaffe and the Wehrmacht's reserves happened, is probably the most underestimated WI in this forum. (Although Douglas Porch argues convincingly how dangerous it was for the Allied victory.)
Well, the alternative would have been a anti-ship missile. The V-1, or a missile like it, is a real possibility here. You install something like the guidance system used on BAT or a television link with remote command control on it. This is launched at a ship or fleet. As it approaches the missile either locks on using its radar, or the operator selects a target within view of the television camera. Either way, it homes on the target and with something like a 1000 to 1500 lbs. warhead it does some serious damage to it.
The problem for the Germans would be that they are not so advanced in guidance technology and their electronics industry is already strained to the max that they could successfully develop and deploy such a weapon.

Even something like the Hegelkorn or US GB-1 is a possibility. These would require mass release, but could be done 30 to 50 miles out from the target area. Against a Normandy-like invasion fleet, what you have are glide bombs sailing through the fleet at somewhere between mast height and waterline. Misses hit the water and detonate. If the glide bomb slams into a ship, then you succeeded.
Yes, that's messy and not very efficient, but it is doable.

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Re: Defeating Invasion Fleets

Post by wm » 13 Feb 2023 20:44

Although contemporary bombs/missiles had no search capabilities, the radar had to be manually locked on target before launch (otherwise, it would go straight into the sea).
The TV link wouldn't work long distances and was very hard to use anyway (the quality was significantly worse than last century tube TV).
And both were easy to jam.

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Re: Defeating Invasion Fleets

Post by Peter89 » 13 Feb 2023 21:25

What I see as a viable option is that long range artillery aims the path of the invasion fleet and artillery observers guide them to hits. But the defender needs an awful lot of guns to make it an effective choice.

Also remote control devices like Goliaths. Mini submarines guided visually, via a cable, carrying a small warhead, just enough to sink a landing craft?
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Re: Defeating Invasion Fleets

Post by wm » 14 Feb 2023 00:44

It seems the Germans were able to attack the invasion fleets with their guided missiles repeatedly - even if without much success because of the jamming and because it wasn't really that easy, so they had to do something right.
I suppose they came low, hiding in ground returns so radar couldn't see them, climbed to the attack height, and then escaped.

If that was possible, then all that was needed was to switch to a different, previously unknown guiding method when D-day would come.
For example, from the radar seeker to the radio and then to, for example, wire guidance.
That gave at least a few weeks before sufficient countermeasures would be deployed.

If the Germans were able to overfly the fleet at a high altitude, then the radar seeker and maybe the contrast seeker (it detected dark spots) would work well - again before countermeasures would be deployed.

But really, the only reliable method to defeat an invasion fleet was the Bomb.

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Re: Defeating Invasion Fleets

Post by T. A. Gardner » 14 Feb 2023 02:48

wm wrote:
14 Feb 2023 00:44
It seems the Germans were able to attack the invasion fleets with their guided missiles repeatedly - even if without much success because of the jamming and because it wasn't really that easy, so they had to do something right.
I suppose they came low, hiding in ground returns so radar couldn't see them, climbed to the attack height, and then escaped.

If that was possible, then all that was needed was to switch to a different, previously unknown guiding method when D-day would come.
For example, from the radar seeker to the radio and then to, for example, wire guidance.
That gave at least a few weeks before sufficient countermeasures would be deployed.

If the Germans were able to overfly the fleet at a high altitude, then the radar seeker and maybe the contrast seeker (it detected dark spots) would work well - again before countermeasures would be deployed.

But really, the only reliable method to defeat an invasion fleet was the Bomb.
Off Salerno they proved reasonably effective, but the Luftwaffe simply could not put up the sort of force necessary to cripple the invasion fleet offshore. KG 100 proved capable of launching attacks using Fritz X there, but they lacked the numbers to really make a dent in Allied landing forces. The same goes for the Anzio landings.

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