German passive sonar was so long ranged that USN copied it post war as did the Soviet . The GHG was ultra low frequency [~ 400hz] was able to detect convoys at @ 50km and their was a case of detection at > 100nm . SOURSES ROSSLER "THE U-BOAT". NORMAN POLAR US & SOVIET SUBMARINES.
Forum: Technology and Operations

Rossler and Groner make mention of splinter protection built into Uboats in 1944. Does any one have information of how much tonnage of armor was installed in each boat?
Forum: Technology and Operations

The Germans conducted 300 sortie with Peroxide development subs during WW-I. They recorded one accident with one fatality. In the context of post war cold war with possible alternatives one can understand the concern over this fuel. However in the context of WW-II when the German uboats were at major risk with every sortie I can see a high speed peroxide boat as being a major improvement!
Forum: Technology and Operations

I can only speculate that No-4-5 could refer to north wind @ force 4-5 . See 4 suggests sea beaufort scale 4 waves. The rest may refer to pressure which is 'rising' "Mitll. Dg. 24 MT. rising, plus 2nd very good Sicht." If you know the day and location you can find basic weather data on the following site... Just type in the date and press the "Zeigen"
Forum: General Discussions

The link says were are not authorized to down load the file! Is there another way to get the file?
Forum: Technology and Operations

According to Rossler the germans conducted 300 sortie with the peroxide test boats. There was only one incident that resulted in death, but this did not halt the programme.It was determined in 1942 that massproduction could begin in 18 months if required but the real problem was lack of bulk H202 production that mostly went to the LW anyway. Considering how dangerous it was for Uboats late in th
Forum: Technology and Operations

Thanks Scott. So it was not very much armor by tonnage and I'm assuming it was mounted late in the war as part of the flak upgrade 1943/44?
Forum: Technology and Operations

According to Rossler’s "The U-Boat", the final installation of equipment is done after the U-Boat is launched and then it is pressure tested before the boat can be accepted as completed product. I believe its then commissioned after the crew is assigned. Commissioned usually means its ready of service, but all boats go through a working up process. For capital ships this could take m
Forum: Technology and Operations

I've read evidence that Uboat conning towers had armor. Does any one know how much armor they had and when it was mounted on the Uboats?
Forum: Technology and Operations

I would guess that if the UBoat is recharging its batteries, its diesels are going full tilt, which means passive sonar is going to be drowned out.
Forum: Technology and Operations

I thought that some of the steps like wheel settings , were done once a day at the start of the shift?
Forum: Technology and Operations

Type 212 runs silent on its electic engines and nearly silent on its Fuel cell AIP drive. The electric drive would be quiter than SSNs and as long as they stay on passive sonar searching they are a lethal threat to any surface group. A few years ago the Royal Navy had to halt an exercise off the coast of Norway because of a single Norwegian Ula diesel/Electric Sub had simulated sinking the Briti
Forum: Technology and Operations

Reading Rosslers book "The Uboat", its apparent that some problems did exist on the XXI design, but these were being worked out through tests in late 1944. It was realised that the flooding slits slowed the boat too much as did the flak turrets . Fast diving and flak was intitally demanded by Donitz for XXI , but when removed, the boats top underwater speed got back upto 17knots. The m
Forum: Technology and Operations

One of the main reasons the wolf packs had to form was due to a lack of operational search capability. Had the LW cooperated with the Uboat fleet, there would not have been such a need to link up Uboats into force search a swath of the ocean for suspected convoys. Had the LW done the searching and issued radio reports then the Uboats only had to monitor those signals and respond if they could
Forum: Technology and Operations

After absorbing Rossler’s book in detail, it references such a design in WW-I with a traversable torpedo rack, similar to Torpedoboot design, it seems. Upon deeper reading I may have been to hasty in my assessment of the speed possibilities by altering the conning tower. The 25% reduction was in resistance, resulting in about a 7% increase in speed . Apparently that stream lining was investi
Forum: Technology and Operations

A fairly convincing American post war analysis of ASW in WW-II is the following ~ 200 page report... It argues convincingly that it was mostly a numbers game on ASW effectiveness. Most ASW attacks were 4% per attack for DC, double that if "Hedgehog" was used and triple that if "Squid" was used. The unusually high figures often associated with these late war ASW syste
Forum: Technology and Operations

I read about the 1/2 degree accuracy in the GHG system with the steerable pod in the XXI, in Rosslers excellent book. I didn't know it could be used to guide a torpedo to within 20 meters @ 2km range. Thats astonding! Can you tell us where you got that info from? I aggree the whole Walter design effort was some what of a waste, but he pointed the way ahead towards Schnorkel subs and
Forum: Technology and Operations

This is a worthwhile site that examines the allied research into the WW-II ASW battle. While its 200 pages in total and baised to the allied cause it presents some interesting data and bench marks to discuss uboat effectiveness in general.
Forum: Technology and Operations

Regular Uboats in WW-II had 18.5mm thick pressure hulls made of ST52 steel. That allowed diving depth of 100m with max depth of 150m and crush depth calculated at 250m. Since the war boats were already risking diving to that crush depth to escape depth charges, they moved to deeper depth. For the Type VIIC/41 they moved to 22mm thick pressure hulls of ST 52 steel and this allowed the figures t
Forum: Technology and Operations

The western allies seem to have done a better job of adjusting technology to their battle plan. The Germans seemed to me more subdivided so each branch had to struggle by itself and thus great duplication of effort. The allied Radar effort produced airborne metric radars by 1941 and decimeter radars by 1943 and cm radars by 1944. German navy prewar was aware of metric radar so had little probl
Forum: Technology and Operations

"The cover casting is of chrome-molybdenum-vanadium steel." Does any one know how much chrome-molybdenum-vanadium steel is used in these Uboats? That was a very limited strategic metal for the Germans to produce.
Forum: Technology and Operations