Karl Doenitz (January 1943)

Karl Doenitz 

January 1943

Grand Admiral Raeder has phoned me and told me he wished to resign. He had proposed the names of myself and Admiral Carls as his possible successors. The great Fuehrer has appointed myself as new Commander in Chief of the Kriegsmarine.

Our position needs to improve if we are to win this war.

Decrypter of Kriegsmarine Transmissions (December 1942)

(name omitted for security purposes)

Decrypter - Kriegsmarine transmissions

Hut 8, Bletchley Park

December 1942

Since Admiral Karl Doenitz changed the Enigma ciphering procedures for the U-boats in February 1942, we hadn't been able to crack the new code. I can still remember my colleagues' expressions when I walked in after the change in ciphers. I asked them what happened, but they just shook their heads. We could intercept all the information we wanted, but we couldn't decrypt it. We knew this day was coming ever since we captured material about the development of the new Enigma machine, but we didn't know when it was going to hit us.

The new German ciphering machine (codename M4) used a four-rotor system, making the cipher much more complex than the previous three-rotor version. We gave the new cipher the codename "Shark", instead of "Dolphin", since it was so much stronger.

From then on, we've worked feverishly to crack this problem - the Kriegsmarine surface units and Baltic submarines still use the old three-rotor procedures, but the information we can glean from them has been very limited. The submarine trackers aren't able to get much information from us, and they have had to rely on agent reports, direction finding, and aerial reconnaissance. It's been a step backwards. Our automated keyfinding hasn't worked for ten months.

That was until three members of the HMS Petard succeeded in capturing one of the codebooks for weather reports in October. After that, we could work backwards to penetrate the new code using the plain-text from the codebooks.

Now we have broken the Enigma code again! We can decrypt German radio signals and send them straight to the Operational Intelligence Centre in London by teletype. The increase in German U-boats and the wolf pack tactics that they have adopted has also allowed us to intercept more radio signals, so we can decrypt their orders and reports.

Instead of locating individual submarines with direction finding, we can again take the fight back to the Germans by figuring out their plans and tactics.

We've been able to teleprint the positions of 10 U-boats to the Operational Intelligence Centre today, and there will be more to come tomorrow.

We are back on track. The Germans will have to look out.

Video - Cracking the Enigma Code

Frederick Kleist, Corporal, U-552 (November 1942)

Frederick Kleist

28 November 1942

U-552, with our emblem of the red devil with two torches signifying life and destruction has had a fantastic campaign so far. We were the first ones to get a US warship, the USS Reuben James, and we are glad that we are sinking tonnage well into the 100,000 tons range. I do have to say that I miss my family, and with the narrow miss the other day (We were attacked by an enemy submarine at the Cape Verde islands) it seems to be like we are not so invincible after all. However, the idiots had torpedoes running close to the surface and our commander obviously had the insight (though I would argue us men do more work than him) to turn away. This war seems to keep going on, and we are perpetually trying to make sense of the directives that Doenitz is giving. Oh well, let's hope we get more of the enemy scoundrels and return victorious to our Motherland.

Karl Doenitz (1942)

Karl Doenitz, 

late 1942

There can no longer be any doubt that even though we have made such considerable progress, the enemy is tactically gaining the upper hand with surface location by destroyers, escort vessels, and aircraft have deprived our tactical advantages. We need to transfer the submarines to a more appropriate under-water element-we need an approach where we have a high underwater speed submarine. We have been testing the high test peroxide turbines which are helping us, and on June 24 I had laid out very clearly that the new Walter U-boats must be speeded up and this is because the U-boats are qua boats, which means their faulty armaments leaves them in an inferior position. I wish to stress how importance of installing the Fu MB which are search receivers and they have afforded considerable relief! Let us push harder.

Grand Admiral Karl Doenitz (1942)

Grand Admiral Karl Doenitz,

1942

Our leaders have learned nothing from the first world war. We have plunged into a world conflict without adequate submarines and failed to expand the U-boat arm, because the leaders and their army and air force advisers believe that they can win a war on land when our main opponents are the two greatest sea powers in the world! We direly need technological improvement and more U-boats! Now that the US is in the picture, we are going up against a monolithic economy. Let's hope we can continue making gains, and hope the leaders honestly wake up to these concerns before it's too late.

Roger Smith, British Merchant Mariner (August 1941)

British merchant mariner

August 1941

We haven't been able to use our usual shipping routes to get to London ever since France fell. Everything has been thrown off schedule – the timings are so unpredictable that our men on the ground can’t even allocate manpower or handle the cargo reliably.

Ever since France fell, everything has to go through the North Channel, and those Germans are picking our vessels off once we head through there. Even convoys aren’t helping. It doesn’t matter if we’re escorted or unescorted, once we head through the North Channel those U-boats start chasing us like a pack of hungry wolves. In fact, the weather and the use of convoys recently has only slowed us down - we can only travel at seven knots when there's a storm, which gives the pack enough time to surround us. The convoys can’t protect merchant ships at night, and the U-boats have been increasing in number lately. It's estimated that there are 36 U-boats at sea every day, when there were only 24 in May. We've lost about 1200 British merchant ships from January to June this year, and we're losing around 260 000 gross register tonnes per month. Some of the escorts - particularly the Royal Canadian Navy fleets - aren't doing their job too. I was under the impression that the convoys were meant to protect the merchant ships, but the escort fleets keep haring off to chase and destroy U-boats, instead of protecting us.

What’s really worrying me isn't my survival, but the survival of our country. It is obvious that our country doesn't have enough ships. I used to think that Britain had a huge merchant fleet. Wasn’t that our pride? But ever since the Phoney War that hasn’t been the case. We’ve been losing ships to U-boats and the weather, and our shipyards aren’t capable of replacing them. Many young shipbuilders went over to the navy or military to do their duty. Three thousand workers from the core of our shipbuilding industry were called up for military service, and only five hundred of them returned to the industry last year. I've heard the news, the Ministry of Labour has recently announced that all of our industries should help the military, and blocked shipbuilders from deferring by subjecting them to military conscription.

Britain has had to purchase about a hundred obsolete secondhand ships from the United States to compensate for the shortfall in domestic production, but even these ships will eventually require repairs at the dockyards. What's going to happen once all the shipbuilders are conscripted? Are we meant to depend solely on American ships? Are we meant to trust the future of our great country's ships to people who haven't worked since the 1920s - cleaners, clerks, and manual labourers? The closest thing the dockyards have to skilled workers are house electricians and hand riveters. I wouldn't trust them to build anything that goes on the water.

Every time we set sail and the sun sets I think that this might be the time where I don’t come back. Between the U-boats, the dreadful weather, and the fickle escorts, I'm not sure which one will get me first. I just hope that our country can survive, even if I don't.