Is Alan Turing's effort code-breaking effort to the war exaggerated?

This is not correct : there were 10 supply submarines,of which 7 lasted almost one year,or more ,3 only were lost very quickly .

 

The Mediterranean was the British mare nostrum /

During 1941/1942, the convoys to NA lost 359000 tons, in the same period, the Allies (mostly Britain ) lost 857000 tons in the Mediterranean .

A loss of 20 % during 2 years does not mean that a freighter survived only 3 voyages,because not all freighters joined the convoys during 2 years: some left for other missions, others arrived,etc...

 

LJAD you have no idea what you are talking about. The Soviets had plenty of information that the Germans were going to attack which is why Zhukov proposed the preemptive attack. Your statement about enigma only furthers your complete ignorance. There were numerous reroutings of convoys due to enigma information. There was the capture of the Uboat with its spare rotors and codebooks that allowed the reading of messages. At one setting of beta, M4 emulated M3, which was M4's undoing. Three members of the British destroyer HMS Petard seized the second edition of the Wetterkurzschlüssel from U-559 on 30 October 1942, before it sank near Port Said. Hut 8 once again had cribs, which it could run on three-rotor bombes, the only type available. The U-boats were using M4 in M3 mode when enciphering the short weather reports. A three-rotor bombe run on 60 rotor combinations therefore took only about 17 hours instead of the 442 hours (18 days) required if M4 had used its full potential.
On 13 December 1942, Bletchley teleprinted the OIC the positions of over 12 Atlantic U-boats, on dates from 5 to 7 December, as established from Shark weather signals. Hut 8 had penetrated M4 Shark with the help of the weather broadcasts broken by Hut 10. Intelligence from Shark, although sometimes badly delayed, played a critical part in the Battle of the Atlantic, perhaps saving from 500,000 to 750,000 tons of shipping in December 1942 and January 1943 alone. http://uboat.net/technical/enigma_breaking.htm
Hut 8's use of the Wetterkurzschlüssel against Shark was short-lived. A third edition of the weather short signal book took effect on 10 March 1943, depriving Hut 8 of cribs. Bletchley had feared that the change would blind it for several months, but by using short signal sighting reports (made by U-boats in contact with convoys and encoded from the Kurzsignalheft) as cribs, Hut 8 re-entered Shark again on 19 March and broke it for 90 out of 112 days before 30 June. Kurzsignalheft short sighting reports also used M4 in M3 mode - and the Kurzsignalheft had also been recovered from U-559.
British and US Navy four-rotor bombes entered service in June and August 1943, respectively, but some July and August Shark keys took up to 26 days to solve. However, from September on, Shark was generally broken within 24 hours. At the end of 1943, work on Shark was transferred to the US Navy's Op-20-G codebreaking unit in Nebraska Avenue, Washington, DC, because the US Navy had over 50 bombes by mid-November.
The main role for naval Ultra was probably in re-routeing convoys, but it was used in many different ways. The US Navy employed Ultra offensively in 1943 and 1944 to sink many of the important supply U-boats (Types XB and XIV, such as U-118, U-233 and U-460), which applied a multiplier effect to the U-boats by replenishing them at sea.

 

All this is meaningless, because, you still does not grasp that re-routeing convoys does not mean less merchant ship losses :most convoys were never detected,and most of those that were detected were not attacked and most attacks failed and the losses of those that were attacked were minimal .

It is the same for the U Boats :less U Bats or more U Boats was irrelevant for the number of merchant losses .

Even U Boat net has to admit that there are no proofs at all that Enigma played a critical role in the U Boat war ERHAPS saving 500000/750000 of GRT in december 1942/january 1943 is meaningless ,it's not even an estimation, it is only a wild guess based on nothing .

I can also say that perhaps between 0 and 1000 GRT were saved ,and this would have the same value. An IF has no value .

It is the same for the milk cows :

First there is no proof that they were sunk because the US navy employed Enigma.

Secondly there is no proof that they would not been sunk without the use of Enigma

Third,there is no proof that without the loss of the milk cows ,the other U Boats would have sunk more merchant ships , because there are periods with big merchant ship losses and without milk cows,and periods with milk cows and with small merchant ship losses . There is no corelation between the number of milk cows and the number of merchant ship losses.

The only thing one can say is that milk cows gave U boats the possibility (not the certainty ) to be longer operational , (how much ? ) ,but to be X days longer operational is NOT the same as more chances to sink a merchant ship , I can also say that longer operational = bigger risk to be sunk .

 

ONE exemple proving that longer on sea does not mean more chances to sink merchant ships is the U 96 : on her first patrol (26 days) she sank 52,901 GRT ,on her 6 th patrol (42 days ) she sank nothing,on her 9th patrol (70 days ) she sank nothing .

There is no proof that,if with the help of a milk cow, she was able to be operational longer during her first patrol, she would have sunk more GRT,that during her 6th/9 th patrol she would have been successful .

 

@lLJAd: Piffle

 

@ Green Slime iffle

 

I declare this a Piffle free zone.

 

Well LJAD I guess you believe that sailing the convoys into areas patrolled by the Uboats would mean that no ships would be lost either. Lets say there was a 1% chance that sailing by a sub would result in contact, due to the wolf pack every contact there is still a chance of a sinking verses 0% chance by avoiding the Uboats, but that is probably too logical for you

 

You still refuse to see the truth,the truth being that the U Boat menace was mythical (convoy losses : 0.33 %/ losses of independently sailing ships : O.66 %,what does not mean that convoys were a better system) and that the role of Enigma (and informations in general ) was less than secundary .

In 1940 24 U Boats were lost ,of which 13 by aircraft ,warships,or both. In how many of these 13 losses was there a role of Enigma? And what was this role ?

In 1941 432 ships and 2.172.000 GRT were lost by submarines ;how many were saved by Enigma .

The German BP (the B Dienst ) was not incompetent,but no one has been able to calculate how many GRT were lost by the intervention of the B Dienst .

In 1942 7558 ships were sailing in the North Atlantic Convoys,of which 169 were lost (not all by U Boats ) .How many of these convoys were rerouted because of Enigma messages ? And how many of these reroutings were correct ? How many ships were saved by these reroutings ?

As the BP lobby is unable/unwilling to give us these answers, we must assume that the number of ships saved by the rerouting of convoys caused by Enigma messages,was insignificant .

During the war,only 10 % of the big trans-Atlantic convoys were attacked, with losses of 10 % ,which means that 99 % of the ships arrived in Britain/America .

About the wolf packs : how many attacks were executed by wolf packs and were attacks by wolf packs more efficient than attacks by lone U Boats ?

It is also questionable to assume that the rerouting of a convoy always resulted in 0 % losses ,because such a rerouting could result in the encounter of other U Boats who were not detected by Enigma;it was also possible that Enigma was wrong and that there were no U Boats in the zone that was avoided .

Besides,were there no cases where it was better not to follow the advice of Enigma and still going through a zone where,following Enigma,there was a U Boat ? Because: detection by a U Boat does not mean attack by a U Boat,and attack by a U Boat does not mean a successful attack .

 

LJAD are you really that ignorant or just a troll. If the convoy system didn't improve things then why the heck did the allies use them. Ernst King thought they were useless like you, but came to accept their importance when they reduced losses after the start of their usage. The reason convoys reduce losses is it allows escorts to combine their efforts and it reduces the opportunity for the subs to hit them. Of course you ignore the effectiveness of convoys in the first war

 

King did not think convoys were useless, but he did perceive that they needed adequate protection - which was not available at the time. Because, unlike the in Atlantic, where a convoy is the proverbial "needle in a haystack", along the American East Coast, there is a far greater chance of it being detected and attacked.

I believe that Blair gives a very good run down on why American coastal convoys were not a good idea at the time.

 

You have reading problems,again : I did not say that the convoy system did improve things . I only question the belief that they improved things .On British side,1012 ships were lost to U Boats sailing in convoy/as straggler= 0.33 %,this means that some 300000 ships sailed in convoy. OTOH,1705 ships were lost sailing independently =0.66 %,which means that 255000 ships sailed indepently .

There are now 2 questions :

1) If the 300000 ships sailing in convoy were saling in dependently ,would more of them have been lost ? And how much?

2) If those sailing independently were sailing in convoy,would less of them have been lost ? And how much ?

Given that we are talking about 2 different types of ships, I am not certain that it would have been a good idea to expand the convoy system to all ships : in the convoy system were sailing fast, middle and slow ships, independently were sailing very fast ships who did not need escorts,and very slow ships who could not be protected by convoy .
An exemple : what was better : to have 10 very fast and 10 very slow ships sailing independently or to have them sailing in convoy where every one (including the escorts ) was sailing at the speed of the very slow ones .

The best protection was speed, not escorts . And there is also the fact that there was always a shortage of escorts .

And as already been said : King was NOT hostile to escorts : as commander of the Atlantic fleet ,he used escorts before PH .

While the losses of ships sailing independently were greater than those sailing in convoy, there is no proof that the reason was that they sailed independently .

The British losses in the Atlantic were

in convoy 711 ships on some 210000

stragglers 215

independently 1427 on some 210000

Source : defeat on enemy attack on shipping P 302

 

That is why there were Fast & Slow convoys, and the very fast ships tended to sail independently.

So your example should be:
A. All fast & slow ships in one slow convoy.
B. Fast ships in one convoy and slow ships in another.
C. Slow ships in a convoy and fast ships proceed independently.
D. All ships proceed independently.

 

Very slow ships tended also to sail independently :there were on British side no 255000 very fast ships sailing independently .

And most convoys were a mixture of fast and slow ships .

 

Then there is also the little matter of insurance, some ship owners and investors were making a lot of money from the situation.

Kind of handy to have an old tug sunk and make a claim with a handsome payout.

 

Returning to Enigma : there were 2 types of Enigma messages : defensive and offensive.

Defensive were messages warning the admiralty that there were 1 or more U Boats in a certain area,U Boats knowing or not knowing that a convoy would cross that area ,ad if it was knwn ,not knowing when and where it would happen .

What would be the reaction of the Admiralty ,if there would a convoy cross that area ? What were the risks for the convoy ? If the U Boats knew that a convoy would come, this did not mean that the convoy would be detected,and if detected, it did not mean that it would be attacked and if attacked, would the attack be successful ?

If a fast convoy of 10 ships with an escort of 4 ships would cross an area where 2 U Boats were waiting/patrolling ,what should do the Admiralty ? Rerout the convoy (if it still was possible) or not rerout ?

There were between1942/1945 1134 convoys in the North and Middle Atlantic. In how many cases was there an Enigma warning, and how many of these warnings resulted in reroutings ? And how many ships were saved by these reroutings?

If there were 100 warnings,who resulted in 20 reroutings of each 40 ships,this mean that 800 ships were rerouted .As the losses of the convoys who were attacked were some 8 %,this would mean that the number of ships that could be saved was 64 .

64 on a total of 47997 !

 

So much wrong in your post, it is barely worth discussing.

Basically, you are using pseudo-mathematics post the event to defend your position, when it is obvious, that the use of decrypts allowed the British to avoid dangerous concentrations of German forces, when the result of not doing so would easily have exceeded the average result. Over the long term, this of course affects the average result on which you try to base your flawed assumption.

Further, it ignores the effect of re-directing other assets (aircraft, destroyers), forcing the u-boats to abort or avoid contact, disturbing the prowl, as was frequently done, reducing the effect of any attack, and also affecting your statistical average.

So not only would there be more attacks, there would be more successful attacks, and more deadly attacks. The consequences of these knock-on effects would be disastrous for the UK.

 

Happy time or glückliche Zeit is a therm used by the U-Boat men to discribe two periods of the naval warfare when they were successful and relatively safe.
And both times did happen exactly when Bletchley Park couldn't decode the radio messages.

The milk cows operated far away from the usual routes, did never attack convoys and usually stayed under warter during daylight, so they were very diificult to find without further information.

 

Three wrong claims

1) The periods where BP could not decode the messages do not coincide with U Boat successes

2 )There was never a Happy Time

3) Most of the milk cows were found and destroyed in the Gulf of Biscaje,by aircraft operating in this area and possessing sophisticated Radar, Enigma had an insignificant role in their destruction .