A WW2 Question

[Sunforged General]

After the D-day landings, were the Germans ever aware of the prefabricated Mulberry harbour's that the allies used to ship in just under half of their supplies? And if they were, why didnt they use an air raid, perhaps even at night to avoid allied air superiority, and destroy the harbour's?

Even with those Harbour's the allies supply situation was strained, without them, an allied defeat in France might have been possible. Especially if the Germans, due to the allies lacking supplies, can hold Antwerp, and thus deny the allies that port, which was a major one.

Could this have been done, and if so, what would have been the effects on the war?

 

[Count Blue]

After the D-day landings, were the Germans ever aware of the prefabricated Mulberry harbour's that the allies used to ship in just under half of their supplies? And if they were, why didnt they use an air raid, perhaps even at night to avoid allied air superiority, and destroy the harbour's?

Even with those Harbour's the allies supply situation was strained, without them, an allied defeat in France might have been possible. Especially if the Germans, due to the allies lacking supplies, can hold Antwerp, and thus deny the allies that port, which was a major one.

Could this have been done, and if so, what would have been the effects on the war?

To my knowledge there were some airraids they were just miniscule in size (a few planes) because of permanent bombing of the originating airports and runways.
Also german airpower was under severe pressure numberwise. The US and UK fighters had caught up at that point to an extent that every mission left the germans with less and less planes and pilots where the US and UK could easily replace lost wings by the dozens.
The germans did not have the naval and airpower at all to contest the landing.
They might have had for a very short time the advantage on land but the spoiled that by taking too long to counter with full forces.
If you dont have air superiority everything becomes very difficult on the ground.

 

[Gil galad]

Mulberry harbours weren't the only harbours used by the allies before the major ports like Cherbourg where captured and cleared for operations.

I can't see any effort the Germans could make that would lead to a lack of supplies and the collapsing of the allied bridgehead.

 

[Sunforged General]

Mulberry harbours weren't the only harbours used by the allies before the major ports like Cherbourg where captured and cleared for operations.

I can't see any effort the Germans could make that would lead to a lack of supplies and the collapsing of the allied bridgehead.

The Allies supply lines on Normandy were already hard pressed, and the Mulberry Harbour's provided just under 50% of the allies supplies, especially in June-July 1944. So how could their loss not have a catastrophic effect on the allied armies in France? The other harbors in use could not handle that extra traffic.

 

[Gil galad]

The Allies supply lines on Normandy were already hard pressed, and the Mulberry Harbour's provided just under 50% of the allies supplies, especially in June-July 1944. So how could their loss not have a catastrophic effect on the allied armies in France? The other harbors in use could not handle that extra traffic.

You forget that one Mulberry Harbour was lost fairly soon after their completion. The allies repaired one after the storms and on the US sector supplies where landed directly on the beach and extra effort was put into expanding the capacity of the smaller harbours. The allies where rather good at this thing called logistics.

 

[Sunforged General]

You forget that one Mulberry Harbour was lost fairly soon after their completion. The allies repaired one after the storms and on the US sector supplies where landed directly on the beach and extra effort was put into expanding the capacity of the smaller harbours. The allies where rather good at this thing called logistics.

i mean you can just throw all of your supplies onto the beach in a chaotic mess, but presumably the reason ports and harbors exist is because they are far more efficient than doing that is.

 

[Gil galad]

i mean you can just throw all of your supplies onto the beach in a chaotic mess, but presumably the reason ports and harbors exist is because they are far more efficient than doing that is.

They are that's why it was imperative to capture a major port like Cherbourg. But even after it's capture the majority of the supplies still came from the beachhead itself.

 

[Rubidium]

The Allies had air and sea supremacy basically from day one, and the radar to detect incoming raids. There's a reason that the Germans invested in the V2; it was the only way to bomb England by that point in the war, as any planes would be shot down (and the V1/V2 are too inaccurate to use to target the Mulberrys).

Also, as noted, one of the Mulberrys was destroyed in a storm shortly after the landing; the Allies decided it was not worth repairing, but if it had been necessary, they certainly could and would have repaired either it or the survivor if they were damaged.

 

[Graf Zeppelin]

Operation Steinbock happend prior to to D-Day. After that the German ability for strategic bombing was spent. So even if considered it wasnt really an option.
On top of that it was done on the expense for German bombing capabilities on other fronts.


Sometimes I think even Skeletor could have handled the Luftwaffe better.

 

[Graf Zeppelin]

You forget that one Mulberry Harbour was lost fairly soon after their completion. The allies repaired one after the storms and on the US sector supplies where landed directly on the beach and extra effort was put into expanding the capacity of the smaller harbours. The allies where rather good at this thing called logistics.

Yes but there is equipment and equipment. The Allies been pretty efficient to ferry palletes to beaches and such. This means howeverer you have to transport fuel in barrels which is horribly inefficient capacity wise.
Also heavy equipment and machinery goes slow that way.

 

[Easy-Kill]

. This means howeverer you have to transport fuel in barrels which is horribly inefficient capacity wise..

Operation Pluto involved the construction of a pipeline under the English channel in support of dday!

 

[Sunforged General]

Operation Pluto involved the construction of a pipeline under the English channel in support of dday!

"During the period from June to October 1944, it carried on average only 150 imperial barrels per day (25,000 litres per day), just 0.16% of the Allies total consumption during the same period."

Operation Pluto was not very successful. In total it only supplied 8% of the total fuel used by the allies between June 1944 and May 1945.

But I suppose it was better to have it, in conjunction with other supply methods, than to not have it.

 

[Easy-Kill]

"During the period from June to October 1944, it carried on average only 150 imperial barrels per day (25,000 litres per day), just 0.16% of the Allies total consumption during the same period."

Operation Pluto was not very successful. In total it only supplied 8% of the total fuel used by the allies between June 1944 and May 1945.

But I suppose it was better to have it, in conjunction with other supply methods, than to not have it.

I am not sure how you describe 8 percent as not very successful. When the western allies invaded Germany in early 1945, they had amassed around a million vehicles and nearly 17000 tanks. 8 percent of the fuel necessary to supply that is a huge amount. You yourself suggested that Germany not acquiring a similar amount from Soviet trade in 1940/41 would have been catastrophic.

PLUTO was never supposed to be the only fuel supply, it was a supplement, something that would provide depth in the case that a harbour was not captured, that the mulberry harbours became damaged or destroyed, or the many other contingencies that the allies planned for and which engages their ability to prosecute the war against Germany.

 

[Sunforged General]

You yourself suggested that Germany not acquiring a similar amount from Soviet trade in 1940/41 would have been catastrophic.

The allies had such an overabundance of fuel being shipped in, Operation Pluto truly was insignificant. Germany on the other hand does not have large oil reserves, the loss of Soviet trade prior to 1941, or say Romanian oil, really would be catastrophic to them. Hitler him self stated in 1942 that if he did not get the oil from the Caucuses in the USSR, he would have to quit the war, implying that the oil from Romania was not enough to sustain Germany long term.

 

[Andre Bolkonsky]

The allies had such an overabundance of fuel being shipped in,

No.

The Allies had MASSIVE reserves of oil. But pumping oil, refining it, and getting it to the front lines where it can be put to best use is very, very difficult. The longer the tether, the greater the fuel expenditure to move it forward.

Patton's armor grinds to a halt in August '44 in Lorraine because the Red Ball Express and the Toot Suite Express cannot keep enough fuel flowing to the front to support both the foolish Market Garden gambit and Patton's armored thrusts.

Pipeline-Under-The-Sea (Pluto) tries the Bambi route into Cherbourg with very limited success. The Dumbo route into Bolougne is much more effective and is an unmitigated success, but doesn't go operational until October.

 

[Easy-Kill]

The allies had such an overabundance of fuel being shipped in, Operation Pluto truly was insignificant. Germany on the other hand does not have large oil reserves, the loss of Soviet trade prior to 1941, or say Romanian oil, really would be catastrophic to them. Hitler him self stated in 1942 that if he did not get the oil from the Caucuses in the USSR, he would have to quit the war, implying that the oil from Romania was not enough to sustain Germany long term.

The allies most certainly did not have an overabundance of fuel. I appreciate that you have read the wikipedia article, but you need to look further than this and critically analyse the facts. The allies had huge issues getting the fuel from storage to the units that needed it (as outlined by @Andre Bolkonsky). Yes, 8% doesn't sound like much, but if you look into the figures, when operational it was supplying about 4000 tonnes of fuel a day.

Somebody did a better calculation on this forum recently (therefore, if somebody can expand, please do). 4000 tonnes of petrol would require about 8000 tonnes of crude oil. If you take the day-rate, and then convert this to barrels of oil, it becomes about 20 Million barrels a year (1.6M barrels per month). To put this in perspective, this was greater than the output of the oil fields that the Germans captured at Maikop. Or even better, the disparity between German oil consumption and availability was about 1.9 Million barrels per month ... that is to say, the Pluto project would have supplied about the same volume of fuel that Germany was lacking throughout the war ... and oft cited as one of the reasons that Germany lost the war.

So yes, it was relatively small when you consider the total volume of fuel used by the allies across the Jun 44 - May 45 period. But when fully operational, it was both substantial and useful. It also offered a degree of diversification if the ports were not captured in time, if the tanker ships were sunk, if weather prevented the ships etc. etc. etc.

The point is, the long, arduous and meticulous logistical planning helped to guarantee allied success in the reconquest of France.

 

[Andre Bolkonsky]

The point is, the long, arduous and meticulous logistical planning helped to guarantee allied success in the reconquest of France.

Agreed.

The point that needs to be reinforced is the critical nature of the time period between disembarkation on the beaches, and the supply fleet returning to England to reload. This period was the period of time SHAEF was most concerned about. And the reason BODYGUARD and all its ancillary operations went into effect to pin down the Germans at Pas de Calais waiting for Patton and FUSAG to land.

Compounding this problem was the German Ordnung in destroying their logisical bases before abandoning them. The loss of the Cherbourg harbor facilities because engineers dynamited the piers one by one. The destruction of the primary rail lines running out to Brest and St. Nazaire. The rail lines west of Paris were in shambles, but east of Paris the infrastructure was much better; allowing the supply lines to open more fully the closer to the Rhine they got.

But, yes, few operations embody the argument 'amateurs study tactics, professionals study logistics' than this campaign.

 

[Sunforged General]

The allies most certainly did not have an overabundance of fuel.

That statement is incorrect. The allies most definitely did have an overabundance of fuel. What they lacked was the logistics to get it to the front lines. But this became less and less the case as 1945 came around.

 

[Andre Bolkonsky]

That statement is incorrect. The allies most definitely did have an overabundance of fuel. What they lacked was the logistics to get it to the front lines. But this became less and less the case as 1945 came around.

He was specifically referring to your assertion the Allies had an over abundance of fuel on the beaches; not the strategic reserves available to the Big Three Allies during the war.

 

[Acheron]

After the D-day landings, were the Germans ever aware of the prefabricated Mulberry harbour's that the allies used to ship in just under half of their supplies? And if they were, why didnt they use an air raid, perhaps even at night to avoid allied air superiority, and destroy the harbour's?

An air raid during the day would be like beating a pack of wolves with a handful of sausages. During the night, how would the German bombers find the harbors? AND drop enough bombs to make a noticeable difference AND not have that mass of bombers torn apart by allied night fighters.

Even with those Harbour's the allies supply situation was strained, without them, an allied defeat in France might have been possible. Especially if the Germans, due to the allies lacking supplies, can hold Antwerp, and thus deny the allies that port, which was a major one.

The Germans held on to Antwerp until 4th September 1944. The allies had to be defeated within few days on the beaches to be defeated. Anything else just slows the allies down but cannot realistically turn the tide.

Could this have been done, and if so, what would have been the effects on the war?

I doubt that the impact would have been severe. The United States had an advantage in production that we do not really appreciate nowadays. Greater supply difficulties might have delayed allied offenses, but any German offense would have to leave their hideouts, march out into the open and become a target of wave after wave of allied airpower from well-supplied Britain.