www.uboat.net

janh · 04-01-10, 10:53 PM

Maybe this is some interesting reading for sub warfare enthusiasts. I stumbles across this site recently and was surprised by the meticulously researched statistics (best patrols, convoy battles etc, sunk and damaged civil and naval ships, subs).

And I was really surprised about the fact that by the end of the war 118 type XXI Electoboats were already commissioned. I thought the number was much much smaller, but in fact within another 3 months they would have been active in numbers.

IanC · 04-01-10, 10:56 PM

Yup, it's probably the best U-boat website out there

looney · 04-02-10, 12:49 AM

http://www.uboatarchive.net/

http://www.uboataces.com/

http://www.uboat-bases.com/

are some other very good sites. If you google on torpedoes you'll come across some other very good ones also.

ReM · 04-02-10, 01:59 AM

Uboatarchive offers some compelling reading (reports on sunk uboats). The owner of the site is a very friendly person as well...
Recommended.

msxyz · 04-02-10, 05:50 AM

Commissioned does not mean operational. It means the vessel is completed, launched and ready to carry preliminary tests. A skeleton crew has been assigned to it to carry out all the rest of the checks and proof tests.

Then, there is the training of the crew itself to familiarize with the boat and the operational procedures.

After that, you can say the boat is fully operational and can be sent to a war zone. The post commissioning phase on type XXI uboats was particulary troublesome.

Due to the modular construction and shortage of good resources and workmanships, several defects in assembling the boat emerged during the first deep dive tests.

Not to mention that, being an entirely new design, everything, from gaskets to engines, to hydraulic and electric systems had to be proofed again and again.

The leakage around the periscope and telescopic snorkel required a redesign of the seals. Entire completed sections had to be scrapped just prior to assembly because the tolerances were too high to grant integrity of the hull once welded together. This problem alone caused a delay of a few months in early 1944. And even after all the minor tweaks of the manufacturing process the boats were proof tested at a depth of 130-140m (480ft says the postwar US report on two captured type XXI) and not deeper. Absolute never to exceed depth was about 220 meters versus a projected value of 280-300.

Several type XXI had the turbochargers removed from the engines (on later boats it wasn't installed at all) because heat and backpressure in real life condition were higher than those measured when the engines ran on the bech. As a consequence, power of each engine dropped to about 1100HP (even less than a type VII !) and maximum speed on the surface was about 14.5 kts.

Even the electrical system had some flaws that were never fully worked out. Internal resistance of the circuits and power lines was higher than expected. This affected the power output of the electrical motors, especially at flank speed, and the boat and endurance at moderate speeds (when the main engines were used instead of the creep motors).

The German industry was already in shambles by the time the elektroboote program was launched. It's incredible that they managed to complete more than a hundred ships in such a short time but the problems were so big that, by the time Germany surrended, only a handful of boats reached war zone and none fired a shot in anger.

janh · 04-02-10, 10:32 AM

Quote:

Originally Posted by msxyz

Commissioned does not mean operational. It means the vessel is completed, launched and ready to carry preliminary tests. A skeleton crew has been assigned to it to carry out all the rest of the checks and proof tests.
...

Buddy, I know what commissioned means. But if you would have spent the time to read the linked reference, you would have seen that a 2-digit number of Electroboats where in the later stages of training and deployment. You could have saved yourself a load of time typing your answer...

BTW, you may revise some of your info after looking more solidly into the topic. The German industry was in shambles, but it had a higher output during the 43, 44 and most likely the highest 45 (propagated) despite the bombings. In the reference you will also see that only a minor fraction of boats was not produced due to bombing campaign, but the major fraction substantially delayed by organizational/logistical mishaps not yet ironed out of the production process. That is impressive, isn't it?

04-01-10, 10:53 PM	#1
janh Stinking drunk in Trinidad Join Date: Jan 2010 Posts: 349 Downloads: 0 Uploads: 0	www.uboat.net Maybe this is some interesting reading for sub warfare enthusiasts. I stumbles across this site recently and was surprised by the meticulously researched statistics (best patrols, convoy battles etc, sunk and damaged civil and naval ships, subs). And I was really surprised about the fact that by the end of the war 118 type XXI Electoboats were already commissioned. I thought the number was much much smaller, but in fact within another 3 months they would have been active in numbers. __________________ Scientific facts are not determined by the opinion of the majority, nor by a democratic vote.

04-02-10, 01:59 AM	#4
ReM Commodore Join Date: Apr 2005 Location: Brewsky, Galore Posts: 618 Downloads: 19 Uploads: 0	Uboatarchive offers some compelling reading (reports on sunk uboats). The owner of the site is a very friendly person as well... Recommended. __________________ Daddy cool

04-02-10, 05:50 AM	#5
msxyz Engineer Join Date: Mar 2005 Posts: 218 Downloads: 14 Uploads: 0	Commissioned does not mean operational. It means the vessel is completed, launched and ready to carry preliminary tests. A skeleton crew has been assigned to it to carry out all the rest of the checks and proof tests. Then, there is the training of the crew itself to familiarize with the boat and the operational procedures. After that, you can say the boat is fully operational and can be sent to a war zone. The post commissioning phase on type XXI uboats was particulary troublesome. Due to the modular construction and shortage of good resources and workmanships, several defects in assembling the boat emerged during the first deep dive tests. Not to mention that, being an entirely new design, everything, from gaskets to engines, to hydraulic and electric systems had to be proofed again and again. The leakage around the periscope and telescopic snorkel required a redesign of the seals. Entire completed sections had to be scrapped just prior to assembly because the tolerances were too high to grant integrity of the hull once welded together. This problem alone caused a delay of a few months in early 1944. And even after all the minor tweaks of the manufacturing process the boats were proof tested at a depth of 130-140m (480ft says the postwar US report on two captured type XXI) and not deeper. Absolute never to exceed depth was about 220 meters versus a projected value of 280-300. Several type XXI had the turbochargers removed from the engines (on later boats it wasn't installed at all) because heat and backpressure in real life condition were higher than those measured when the engines ran on the bech. As a consequence, power of each engine dropped to about 1100HP (even less than a type VII !) and maximum speed on the surface was about 14.5 kts. Even the electrical system had some flaws that were never fully worked out. Internal resistance of the circuits and power lines was higher than expected. This affected the power output of the electrical motors, especially at flank speed, and the boat and endurance at moderate speeds (when the main engines were used instead of the creep motors). The German industry was already in shambles by the time the elektroboote program was launched. It's incredible that they managed to complete more than a hundred ships in such a short time but the problems were so big that, by the time Germany surrended, only a handful of boats reached war zone and none fired a shot in anger. __________________ ...Sinking deeper into the cold, dark oceans of life

04-01-10, 10:56 PM	#2
IanC Grey Wolf Join Date: Nov 2008 Location: Running silent and deep Posts: 902 Downloads: 3 Uploads: 0	Yup, it's probably the best U-boat website out there

04-02-10, 12:49 AM	#3
looney Commodore Join Date: May 2007 Location: Sneek, The Netherlands Posts: 635 Downloads: 43 Uploads: 0	http://www.uboatarchive.net/ http://www.uboataces.com/ http://www.uboat-bases.com/ are some other very good sites. If you google on torpedoes you'll come across some other very good ones also.