Battle of the Atlantic

[1979]

Incorrect, I made that statement to show how the US escort duties prior to the entry in to WWII were not a complete analog for real combat training. The US had to physically block the u-boats not hunt them down. This is what got the USS Rueban James killed.

OK I see

Yes it could, from August 41 a u-boat's periscope could be detected from radar equipped warships in favorable conditions out to about 1 mile.

with what radar set ?

[Monash]

The Mother load

Fellow WABERS ,
I have always considered the Battle of the Atlantic to be the key campaign of WW11 as defeat in this campaign in 39-42 would have forced Great Britain to terms with the Axis for face starvation. I also recalled reading in th epast about the "maths" involved in organising/deciding the optimal size for convoys (a branch of maths operation research) so I did some digging.

http://www.ibiblio.org/hyperwar/USN/...51/ASW-10.html

Here is a "mother load" on all things naval during the war - the Hyperwar Foundation is a great recource. The chaptwer is question is part of a report titled "ANTISUBMARINE WARFARE IN WORLD WAR II, by Charles M. Sternhell and Alan M. Thorndike for the Operations Evaluation Group, Office of the Chief of Naval Operations, Navy Department, Washington, D.C., 1946

I hope you find it as interesting as I did. Cheers

[zraver]

OK I see


with what radar set ?

Still digging for the actual set, but I know RN corvettes began using radar and achieved a kill in may 41. When the US joined the war, Comsubpac gave subs standing orders to attack by sonar only with no periscope to avoid Japanese radars. Which ended up being backwards as Japanese acoustic gear was very good and radar non-existent. But this implies US/UK radar was good enough to do it or the USN would nt have know radars could do it.

[1979]

HMS Orchis with type 271 but the distance is listed at 900 yards ( 823 meters )
ASDIC, Radar and IFF Systems Aboard HMCS HAIDA - Part 8 of 10


but for practical proposes that is far to short to be useful, no ?

[zraver]

HMS Orchis with type 271 but the distance is listed at 900 yards ( 823 meters )
ASDIC, Radar and IFF Systems Aboard HMCS HAIDA - Part 8 of 10


but for practical proposes that is far to short to be useful, no ?

Depending on circumstance maybe. IIRC the U-boats which had a higher top speed than a lot of the British escorts like to get inside the convoy for gunnery work so the ranges were already short and there were a lot of false radar images. Detecting a sub slipping by in the mist or the fog becomes possible, something that could not be done in WWI.

The [combined] results speak for themselves. In WWI for the loss of 183 boats the Germans sank 5000 vessels and damaged a further 2600. In WWII the u-boats lost 780ish boats and sank less than 3500 vessels.

[clackers]

Sinking over 800,000gwt of shipping in a single month is under achieving?

Only because Sir John Jellicoe (the 'victor' of Jutland) was making the same mistake as Ernest King 35 years later - coming up with excuses for not implementing convoying.

Merchant ships were allowed to independently make their way across the Atlantic at the same time as precious naval resources were being wasted in futile sub hunting missions without radar or sonar (this document is typical of his response to the U-boat threat: Jellicoe Memorandum on submarine warfare, 29 Oct 1916 - Wikisource)

Convoying was introduced against his wishes and was amazingly successful. The 800,000 tons you mentioned were sunk in April 1917, and this fell to 365,000 in July.

By September, in eighty convoys 1306 ships were able to sail to Britain, of which only ten were sunk.

Karl Doenitz was to write of this development:

The oceans at once became bare and empty; for long periods at a time U-boats, operating individually, would see nothing at all; and then, suddenly, up would loom a huge concourse of ships, thirty or fifty or more of them, surrounded by an escort of warships of all types ... The lone U-boat might well sink one or two of the ships, or several, but that was a poor percentage of the whole. The convoy would steam on bringing a rich cargo of foodstuffs and raw materials to port.

Jellicoe was to pay for what was now obvious to all had been a mistake.

By Christmas he would be sacked as First Sea Lord by the PM, David Lloyd George.

[zraver]

Only because Sir John Jellicoe (the 'victor' of Jutland) was making the same mistake as Ernest King 35 years later - coming up with excuses for not implementing convoying.

A bit more than "Only", not many British destroyers had the range to zig-zag across the Atlantic, let alone make the trip up from Africa zig-zagging. Further a large number of destroyers were with the Grand Fleet leaving trawlers and armed merchies as the bulk of the force to face the uboat. They did well enough that Germany felt they had to resort to unrestricted submarine warfare.

Jellico is also the father of the depth-charge and the destroyers and escorts he had to work initially only had 2 each, by 1918 they would have 30+

Without the benefit of hindsight and without the disadvantage of the convoy propaganda about killing u-boats there are a lot of good reasons to choose solo operations.

Merchant ships were allowed to independently make their way across the Atlantic as precious naval resources were wasted in futile sub hunting missions without radar or sonar (this document is typical of his response to the U-boat threat: Jellicoe Memorandum on submarine warfare, 29 Oct 1916 - Wikisource)

1. Some merchants are faster than the most common escorts.

2. some are slower

3. a convoy is only as fast as its slowest member

4. a convoy concentrates targets for the enemy (as the wolf packs would show)

5. Some merchants were sail, some steam and if you mixed them what do you do in a doldrum?

Convoying was introduced against his wishes and was amazingly successful. The 800,000 tons you mentioned were sunk in April 1917, and this fell to 365,000 by July.

By September, in eighty convoys 1306 ships were able to sail to Britain, of which only ten were sunk.

Yup, but there was a strong logic against convoys, it proved mistaken, but it was not based on poorly thought out reasoning.

Karl Doenitz was to write of this development:

The oceans at once became bare and empty; for long periods at a time U-boats, operating individually, would see nothing at all; and then, suddenly, up would loom a huge concourse of ships, thirty or fifty or more of them, surrounded by an escort of warships of all types ... The lone U-boat might well sink one or two of the ships, or several, but that was a poor percentage of the whole. The convoy would steam on bringing a rich cargo of foodstuffs and raw materials to port.

Jellicoe was to pay for what was now obvious to all had been a mistake.

That is the fate of commanders who bet on the wrong horse. However, if the Germans had adopted wolf packs in the fall of 1917...

By Christmas he would be sacked as First Sea Lord by the PM, David Lloyd George.

Which had very little to do with submarines and more about the internal politics between the military and DLG.

[1979]

The [combined] results speak for themselves. In WWI for the loss of 183 boats the Germans sank 5000 vessels and damaged a further 2600. In WWII the u-boats lost 780ish boats and sank less than 3500 vessels.

that is one way to look at it,
However the overall tonnage sunk in ww2 was larger, despite the fewer number of ships attacked, despite the use of convoys, despite
higher casualties, despite the technological advantages in aircraft/aircraft carrier and submarine detection technology.

[clackers]

A bit more than "Only", not many British destroyers had the range to zig-zag across the Atlantic, let alone make the trip up from Africa zig-zagging. Further a large number of destroyers were with the Grand Fleet leaving trawlers and armed merchies as the bulk of the force to face the uboat. They did well enough that Germany felt they had to resort to unrestricted submarine warfare.

Jellico is also the father of the depth-charge and the destroyers and escorts he had to work initially only had 2 each, by 1918 they would have 30+

There were enough escorts. The destroyers were with the Grand Fleet because Jellicoe wanted them with the Grand Fleet.

His staff officers' incompetent modelling claimed protection couldn't cover the 2500 weekly sailings from Britain, but of them, actual ocean going merchant ships sustaining the war were only around 130.

The depth charge is only useful if a sub's detected, but a hydrophone from 1917 could only pick up a target hundreds of yards away. No wonder, then, that Jellicoe's aggressive sweeps for subs were complete failures. Operation BB used up 49 destroyers for 111 futile days off the Scottish coast.

[clackers]

Yup, but there was a strong logic against convoys, it proved mistaken, but it was not based on poorly thought out reasoning.

The reasoning was terrible - I have it here from the Admiralty's Operational Division: " ... it is evident that the larger number of ships forming the convoys, the greater is the chance of a submarine being able to attack successfully", concluding that sailing independently was the safer procedure.

This is poor logic, as Doenitz verified as a working submarine commander. In the Atlantic, a group of ships is little more conspicuous than a single ship. Single ships sailing independently in succession multiply the chances of being sighted.

It's also a better use of limited naval escorts - make the merchant ships come to them, not the other way round. A big advantage is that the destroyers have radios, rare in cargo ships of the time.

The radios mean that transmissions from U-boats decoded by the Admiralty's Room 40 could re-route convoys as needed.

As for what you do with slower or faster ships, you can treat them as separate risks. Even in WW2, Australian troops were sent to the Middle East en masse on unescorted liners like the Queen Mary because no submarine could hope to catch them at full throttle.

Sailing ships are likely to take routes according to winds anyway ... and BTW convoying of these kinds of ships had been implemented successfully by the RN in Napoleonic times in response to French commerce raiders ("Master and Commander" et al)

[clackers]

However, if the Germans had adopted wolf packs in the fall of 1917...

They'd have needed better boats than the ones they had, a totally different doctrine (Doenitz drilled his captains prewar in groups of surface torpedo boats), and radio technology would have had to advance, too, for subs to communicate with each other across the Atlantic (and remember that the RN had cracked their codes as well).

In any event, the impact of U-boats was overestimated at the time by everybody. Perhaps 750,000 Germans died of starvation during the Allied blockade, while food production actually increased in Britain and mortality rates among the working classes declined.

The American, British, Japanese and German navies went into the Second World War believing (mistakenly) that in light of new technologies, submarines were of limited value.

[clackers]

Which had very little to do with submarines and more about the internal politics between the military and DLG.

Well, Spencer Tucker in World War I notes: "Although considered an extraordinarily talented administrator and a reasonably astute tactician, Jellicoe has been criticized as a poor strategist and as overly cautious ... Prime Minister David Lloyd George sacked him in December 1917, believing him not up to the task of eliminating the U-boat threat."

And you can see why reading Jellicoe's memo to Cabinet that I linked above.

Not what you want to hear from your naval Chief of Staff ... it contains a lot of hand-wringing pessimism, admits it makes no concrete proposals, and doesn't mention convoying, about which other senior naval figures would have been whispering to the politicians.

[Dreadnought]

Well, Spencer Tucker in World War I notes: "Although considered an extraordinarily talented administrator and a reasonably astute tactician, Jellicoe has been criticized as a poor strategist and as overly cautious ... Prime Minister David Lloyd George sacked him in December 1917, believing him not up to the task of eliminating the U-boat threat."

IMO,Jellicoe was not a poor strategist by any means. Jutland alone and the events just prior too and after the battle confirm this. Even Scheer from his own experiences at Jutland would later write that Germany must never do this again or no doubt they will destroy us at sea. That comes from his own writings. I do agree Jellico lost more men and more ships but he also retained control of the North Sea and other vital shipping routes which was key to defeating Germany in WWI and keeping the supplies coming.

[clackers]

I do agree Jellico lost more men and more ships but he also retained control of the North Sea and other vital shipping routes which was key to defeating Germany in WWI and keeping the supplies coming.

Yes, Dreadnought, although, after 1916 it was David Beatty who 'retained control of the North Sea and other vital shipping routes'. Jellicoe had been moved away from the Grand Fleet and into Whitehall.

[zraver]

Well, Spencer Tucker in World War I notes: "Although considered an extraordinarily talented administrator and a reasonably astute tactician, Jellicoe has been criticized as a poor strategist and as overly cautious ... Prime Minister David Lloyd George sacked him in December 1917, believing him not up to the task of eliminating the U-boat threat."

And you can see why reading Jellicoe's memo to Cabinet that I linked above.

Not what you want to hear from your naval Chief of Staff ... it contains a lot of hand-wringing pessimism, admits it makes no concrete proposals, and doesn't mention convoying, about which other senior naval figures would have been whispering to the politicians.

Again, he was caught up in DLG's private war against the military top brass. Jellicoe may have guessed wrong on the best way to combat the U-boat, but given the resources he had and what he was expected to protect it was not a failure of effort. Yes the British military used convoys for movign troops- big fast liners, not slow plodding merchantmen or even slower sailing vessels. In WWII the convoy system very nearly wrecked the UK when the lack of escorts allowed U-boats operating in wolf packs to sail around at will inside of escorted convoys sinking ships with gun fire.