New U-Boats

As a side note on AA weaponry. By the latter stages of the war there were quite a few boats that had armament beyond the "standard," not that it really helped much.

Experienced U-boaters like Erich Topp saw the value in the Type XXI. It was the corner-turner to a true submersible. Had Germany gone on unhindered into the later 1940s development of the Walter catalytic system would have probably been developed, modified and enlarged for use on boats the XXI's size.

And a true submersible is what was needed at the end since even just raising the Snort could be picked up on radar with the coverage the Allies had.

 

speaking of Flak onbord on U-booten the order though not always carried out but during 1943 the "Barbara" refit was to take place with a standard single barrel 3.7cm along with two 2cm Zwillings near the conning tower, the forward 8.8cm was removed. there was a variety of Fla refits 2cm's in twin form, and single, 2cm Flakvierlings, 3.7cms to the front and back and even late war 3.7cm Zwillings included.

I actually think the much smaller XXIII may have been more effective planting themselves near the English coasts very stealth like and into the channel

 

I wonder if you guys know about this?
Just came across this info and sounds interesting.
the U-234

 

Speer and the new subs

" Speer had reexamined initial delivery estimates and promised the first type XXI in April 1944. To expedite their availability, Speer built these new submarines in a radically new fashion. His biggest gamble was to rush the submarines into production straight from the design stage, without first building a prototype.To ensure a smooth transition to the new building program Speer established a Central Board for Ship Contruction in the summer of 1943. This committee consisted of representatives from the navy and the Armaments Ministry;it was headed by Otto Merker, whose previous experience was in the automobile industry.

To reduce the amount of time and the number of workers required to build the U-boats, Merker proposed bulding the new submarines in prefabricated sections to be fitted together according to assembly-line procedures. Naval engineers concluded that building the Type XXI in eight sections would cut construction time from at least twenty-two months to as little as five to nine months.In addition, early estimates revealed that sectional construction would reduce slip time by 50 percent.

Industry throughout the Reich produced submarine engines and accessories, and thirty-two inland factories built the prefabricated sections.From these factories the sections, weighing up to 150 tons, proceeded via inland waterways to eleven fitting-out yards near the coast. Finally, the completed sections went to three nearby shipyards- in Danzig, Bremen,and Hamburg- for assembly.Dönitz placed orders for 170 type XXI and 140 type XXIII U-boats in the fall of 1943.

Many delays resulted from simple poor planning. The worst example was rushing the submarines into production.Inexperience with sectional construction also caused serious problems. The tolerance for fitting sections together ( initially plus or minus two millimeters for sections seven meter high and six meters wide ) was rarely met, which meant that there was a good bit of shuffling sections around in hopes of finding a better match. Section ends often had to be stretched, shrunk, or patched to obtain a fit.Another problem was that the type XXI submarines incorporated hydraulic power for all control systems and the periscope, antiaircraft armament, and torpedo hatches. But the Germans were relatively inexperienced with hydraulic design, and defects in the system led to chronic delays.

On several occasions shortages of various components, such as batteries, periscopes, or electric motors, usually caused by Allied bombing, postponed production. many sections arrived at the assembly yards with essential components missing.

Further, although Hitler had assured Dönitz on 24 September 1943 and again on 26 February 1944 that he would support any measures to accelerate production of the new U-boats, in April 1944 he suddenly granted fighter production top priority. This confusion in armaments production also contributed to delays.

From Hitler, Dönitz and the Baltic sea By Howard D Grier

 

Interesting, and highly imaginative, reading. I wonder though; according to everything I've read about the German nuclear program indicates that it was even further behind the curve than the Manhattan project. There was, for example, no operational German reactor, which was necessary for research into uranium, enrichment. Nor, apparently, did the Germans have any facility which could consistently enrich even small amounts of uranium. The only uranium enrichment which is known to have taken place in the Third Reich was small batches of uranium enriched experimentally in temporary laboratories by German physicists. So I seriously doubt the 550 Kilos of uranium aboard the U-234 was in any way enriched uranium. If it had been, the men opening the containers almost certainly would have received fatal dose of radiation poisoning. The bit about Oppenheimer being there is pure fantasy; he was much too busy at that time to be looking ofr fissionable material.

Second, it's unlikely the U-234 uranium went to the Manhattan project. The project already had enough fissionable material to build the one and only uranium bomb by June of 1945. and the uranium on U-234 wouldn't have gotten there befoe that time if the U-234 was cpatured in mid-May. The first atomic bomb tested at Trinty site in July was a plutonium bomb, so the nonsense about the Americans not being able to trigger a plutonium bomb is just that, rubbish. The fact is the plutonium bomb was preferred over the Uranium bomb because it was easier to produce plutonium than to enrich uranium and the trigger mechanism was no more difficult to produce. It was alos known that pound for pound, the plutonium bomb was more powerful.

The whole thing sounds to me like one of The History Channel conspiracy theories designed to attract attention, it's just not plausible.