This forum is for discussing technological & operational matters pertaining to U-boats. http://www.uboat.net/forums/list.php?20 Sun, 22 Nov 2009 04:01:26 +0100 Phorum 5.2.7 http://www.uboat.net/forums/read.php?20,81519,81519#msg-81519 http://www.uboat.net/forums/read.php?20,81519,81519#msg-81519
At the museum of Chicago, U-505 was moved inside and had to have a lot of refurbishment done. The boat suffered in the Chicago weather, and they say it was only built to last 4 years.

This surprised me, I can't find much information but I think I've seen a reference to boats lasting 10 years in service on this site.

Do we know how long a u-boat was designed to last, or does it vary a lot depending on the type? And how long did they last in reality?

Thanks]]> Paradroid Technology and Operations Thu, 19 Nov 2009 19:48:42 +0100 http://www.uboat.net/forums/read.php?20,81374,81374#msg-81374 http://www.uboat.net/forums/read.php?20,81374,81374#msg-81374
Can anyone tell me what material was used on the shaft bearings on u-boats and other European nation's submarines?

Curious,

ROBERT M.]]> ROBERT M. Technology and Operations Sun, 01 Nov 2009 21:07:45 +0100 http://www.uboat.net/forums/read.php?20,81201,81201#msg-81201 http://www.uboat.net/forums/read.php?20,81201,81201#msg-81201 It was dived by Innes Macartney and the boat is covered in a rubber material all over which has holes in it, the rubber is laid in two layers and glued to the Uboat completley. The purpose of the rubber is to absorb the sonar from Asdic Sets and make the Uboat invisible in the water. U480 sank 5 ships in 5 days without detection in the English channel around the D-Day landings period. She was sunk on her next mission by a deep laid mine after the Britsh read her signals at Blecthly and mined the convoy route U480 had been working. They said in the documentory that another six Uboats had been covered in the rubber and were never discovered. I just wondered if anyboady has heard of this before and could name the other six Uboats or if they were the same class of boat etc.
Makes you wonder if they had done this to a type XXI the war could have been a different story.]]> Bob Abella Technology and Operations Tue, 20 Oct 2009 08:18:59 +0200 http://www.uboat.net/forums/read.php?20,81134,81134#msg-81134 http://www.uboat.net/forums/read.php?20,81134,81134#msg-81134
Here's a photo of the Gyro Angle Indicator main dial (there's another one for units) - Torpedo Lauf Winkel
[elanaiba.smugmug.com]

The thing that puzzles me is the addition of some sort of salvo indicator, with spreads for 2,3 and 4 torpedoes salvoes. Aparently this doesn't rotate, so can only be read on the ~270 degrees position.

What am I missing here?]]> elanaiba Technology and Operations Thu, 24 Sep 2009 10:09:13 +0200 http://www.uboat.net/forums/read.php?20,81029,81029#msg-81029 http://www.uboat.net/forums/read.php?20,81029,81029#msg-81029 paul tjader Technology and Operations Sat, 05 Sep 2009 00:24:21 +0200 http://www.uboat.net/forums/read.php?20,80929,80929#msg-80929 http://www.uboat.net/forums/read.php?20,80929,80929#msg-80929
Referring to Report on U-570 -- HMS Graph, edited by you, the following statement
appears on page 30, Para. 69:

"When charging [electric torpedoes] a [screened] ventilating door [handhole cover] is fitted to the torpedo in place of one of the [regular handhole covers] access doors and the catalyser is used to deal with the hydrogen given off."

What type of catalyser was used?

U.S. battery-powered Mark 18 torpedo [copied from the German G7e] used a built-in ventilation tube using low pressure air, and later, using a hydrogen burner arrangement, when a tube-loaded torpedo had to be ventilated. When the U.S. Mark 28 [passive-acoustic, [copied from German T5] battery-powered torpedo was issued [just prior to the end of WWII], it had palladium catalysts installed throughout the battery compartment to eliminate the continuously accumulating hydrogen.

Awaiting your answer,

ROBERT M.]]> ROBERT M. Technology and Operations Sun, 16 Aug 2009 19:48:31 +0200 http://www.uboat.net/forums/read.php?20,80793,80793#msg-80793 http://www.uboat.net/forums/read.php?20,80793,80793#msg-80793
On 22 January 1944 the B.d.U. ordered to U-boats to make experiments, testing of possibilities of direction finding in the Atlantic. The U-boats had to take bearings of Very Low Frequency (VLF) coastal transmitters located on the both sides of the Atlantic and to fix the U-boats positions, and to check the accuracy of such obtained positions by means of dead reckoning and astronomical navigation. The transmitters worked on the frequencies around 20 kHz.
The transmitters were German but also British, American and Spanish. It was good idea, actually. The transmitters' positions were known, they worked on VLF and the frequencies are the best for direction finding.
But, I am not sure if the U-boats could to take bearings when they were submerged.
Of course, the Germans received VLF messages from their transmitters Nauen and Goliath when the U-boats were submerged, by means of DF receivers and their loop antennas.
But, it is different when you just receive message or when you have to take bearing.
There is not perfect accurate bearing because radio waves pass through different media, line between land and sea etc etc. Yes, VLF radio waves are the best for bearing, but still, there is always some kind of inaccuracy.
I am sure that even when a U-boat was submerged that radio operators were able to take some kind of bearing by rotating the loop antenna around its axle, but how bearing obtained on such way was? After all, the radio signal passed through different mediums, air and water, in its way from the transmitter to the loop antenna (of submerged U-boats).
There must be some kind of refraction, but how big the reflection was?

After WW2 the Omega navigational system has been introduced. Omega work on VLF, between 10 and 14 kHz. Submerged submarines used the system because VLF could be received under the surface. A submarine Omega receiver measures phase difference of signals and by means of special Omega charts and those days by Omega receiver which display directly the submarine position they could fix the position.

I mean, if submerged submarines could to use Omega system, which worked on VLF (10-14 kHz), was it possible for WW2 (submerged) U-boats to take bearings on land VLF transmitters which worked on similar frequencies, around 20 kHz.
It is pure technical question, and on my shame I don't know the answer :)

Best regards!
Funkmeister]]> Funkmeister Technology and Operations Sun, 26 Jul 2009 11:35:08 +0200 http://www.uboat.net/forums/read.php?20,80775,80775#msg-80775 http://www.uboat.net/forums/read.php?20,80775,80775#msg-80775 nbracco@hotmail.com
Another thing, does anybody know which boat is the one shown in the article about FuMo 29 in this web?
Thanks in advance!
Nicolas]]> nicoo Technology and Operations Mon, 03 Aug 2009 18:26:16 +0200 http://www.uboat.net/forums/read.php?20,80760,80760#msg-80760 http://www.uboat.net/forums/read.php?20,80760,80760#msg-80760
Just ran across this little tidbit........

"In 1944 General George S. Patton's Third Army was racing across southern France. In
his haste to be the first U.S. commander to cross into Germany, however, Patton
overextended his supply lines. His armored columns ground to a dead stop. Faced
with the choice of waiting until he could be resupplied or draining the fuel of
captured German vehicles, Patton chose the latter. His tanks and armored personnel
carriers continued to steamroll toward Germany, powered by the German's own ersatz
gasoline - synthetic fuel manufactured from coal."

I have a question. Was synthetic diesel fuel produced for U-boat use also?

Answers will be appreciated,

ROBERT M.]]> ROBERT M. Technology and Operations Thu, 16 Jul 2009 09:12:41 +0200 http://www.uboat.net/forums/read.php?20,80745,80745#msg-80745 http://www.uboat.net/forums/read.php?20,80745,80745#msg-80745
Heddy Lamar co-owned the patent (2,292,387) for a frequency hopping radio system to be used in Radio Controlled Torpedoes.

While this technology was not implemented until 1962, historical references about Lamar's work refer to radio controlled torpedoes currently (1942) being used by the US Navy.

The word "used" may be misused in place of "being developed". But in any case, I have not heard of any development during WWII of a radio controlled Torpedo.

Does anyone have any references for this work? I know that we, and other countries, were working on wire guided torpedoes but I have not read anything about radio controlled torpedoes.]]> ThomasHorton Technology and Operations Mon, 13 Jul 2009 22:41:50 +0200 http://www.uboat.net/forums/read.php?20,80742,80742#msg-80742 http://www.uboat.net/forums/read.php?20,80742,80742#msg-80742
This is news to me.....

"March 7. 1942 The practicability of using a radio sonobuoy in aerial anti-submarine warfare was demonstrated in an exercise off New London, CT by the K-5 blimp and the S-2 submarine. The buoy could detect the sound of the submerged submarine's
propellors at a distance up to 3 miles, and the radio reception aboard the blimp was satisfactory up to 5 miles."

"October 29, 1942 Procurement of the expendable radio sonobuoys for use in anti-
submarine warfare was initiated as the Commander-in-Chief, U.S. Fleet directed the
Bureau of Ships to procure 1,000 sonobuoys and 100 associated receivers."

Regards,

ROBERT M.]]> ROBERT M. Technology and Operations Mon, 13 Jul 2009 22:31:29 +0200 http://www.uboat.net/forums/read.php?20,80586,80586#msg-80586 http://www.uboat.net/forums/read.php?20,80586,80586#msg-80586 Regards
James, England, UK]]> collinsjr Technology and Operations Mon, 22 Jun 2009 11:16:47 +0200 http://www.uboat.net/forums/read.php?20,80318,80318#msg-80318 http://www.uboat.net/forums/read.php?20,80318,80318#msg-80318
Whenever you see a wreck of a U-Boat it always seems in very poor condition'especially the conning tower.

In fact the conning tower seems to have rusted away and all thats left is masts and periscopes.

So i'm wondering if the metal used for conning towers is different to the metal uses for the pressure hull that might explain how conning towers seem to rust away?

Thanx]]> Dave McQueen Technology and Operations Wed, 20 May 2009 11:43:50 +0200 http://www.uboat.net/forums/read.php?20,80239,80239#msg-80239 http://www.uboat.net/forums/read.php?20,80239,80239#msg-80239
Can anyone tell me what might be common small arms found onboard a U-Boat?

I'm writing a story, and have a party from a boat going ashore, and would like to be accurate in my description of what weapons they'd be carrying.

Thanks in advance, guys.]]> Lord Vince Technology and Operations Fri, 08 May 2009 06:45:49 +0200 http://www.uboat.net/forums/read.php?20,80080,80080#msg-80080 http://www.uboat.net/forums/read.php?20,80080,80080#msg-80080 Nestor]]> Nestor Technology and Operations Wed, 15 Apr 2009 18:23:33 +0200 http://www.uboat.net/forums/read.php?20,80046,80046#msg-80046 http://www.uboat.net/forums/read.php?20,80046,80046#msg-80046 A/A Armament of the U-617 (Flak) in 1943?

One of the questions on U-617 as intrigate is precisely this: What type of AA armament carries? As you seen, In this detail, zoom of a photo of this book: [www.amazon.co.uk] Due at the quality of the photo isn't posible determine what is present at 12/September 1943 (date of the varashment).



Page 117 Ref AIR 15/471 U-617 left and beached.

I remark with red lines finds interesting.....

Are a A/A gun of 37 mm caliber near the bow?
Two twin 20 mm Flak in the Wintergarten? Are these spots over the water?

A single 20 mm Flak in bridge?
Two single 13,2 mm in rear platform?

Any can share with our investigation a photo in the epoch?



Our documents only talks about "Recovered three pieces from the bottom of the sea, near at the submarine by a buzo/submarinist"

Any indication for confirm these interrogants are welcome.





Jan.]]> Jan7 Technology and Operations Fri, 10 Apr 2009 16:11:52 +0200 http://www.uboat.net/forums/read.php?20,80011,80011#msg-80011 http://www.uboat.net/forums/read.php?20,80011,80011#msg-80011
What is the lever inside the red circle in this picture?

]]> Åkerberg Technology and Operations Sat, 04 Apr 2009 11:28:37 +0200 http://www.uboat.net/forums/read.php?20,79988,79988#msg-79988 http://www.uboat.net/forums/read.php?20,79988,79988#msg-79988
for an open source WWII naval warfare simulation i need several scans of historical material.

1st: a high quality scan of a Kriegsmarine nautical chart(for u-boats) which shows the used colors, contained information such as depths, convoy routes and maybe geographical information like map projection, date, etc. I know that there are several maps available in the internet which show the Kriegsmarine grid system but i need a real nautical chart which was used to navigate.

2nd: A scan/pdf of "Reinhart Reche ('Die Quadratur der Meere' zur Umrechnung der Marine Quadratkarte 1939-1945 Marine Rundschau, 81 (1984), 120-122)" As i wrote in another topic that this article contains informations how to transform the grid coordinates.

3nd: Some scans of "Die Handelsflotten der Welt" so we can give our ship recognition book a much more realistic look.

Of course contributors will be mentioned in the credits :)

Thanks in advance]]> MBady Technology and Operations Thu, 25 Jun 2009 10:45:28 +0200 http://www.uboat.net/forums/read.php?20,79987,79987#msg-79987 http://www.uboat.net/forums/read.php?20,79987,79987#msg-79987
Anybody knows how the torpedo light signal indicator system works? (lampentafel)



Cheers]]> Åkerberg Technology and Operations Thu, 02 Apr 2009 11:46:35 +0200 http://www.uboat.net/forums/read.php?20,79986,79986#msg-79986 http://www.uboat.net/forums/read.php?20,79986,79986#msg-79986 Jerry Cornford]]> Jerry Cornford Technology and Operations Thu, 02 Apr 2009 03:24:34 +0200 http://www.uboat.net/forums/read.php?20,79983,79983#msg-79983 http://www.uboat.net/forums/read.php?20,79983,79983#msg-79983
I am new to the message boards, and was hoping someone could help me out. I am researching the German Torpedo Crisis and I have come across several terms for which I am at a loss understanding. I frequently see the terms "NAHSCHUSS" "SCHNELLSCHUSS" "TAGWEITSCHUSS" "SCHARFSCHUSS" "NETZSCHUSS" and "WEITSCHUSS" used when describing various types of torpedo shots. Although I know the literal translation, I dont know what they refer to in practice. There also appears to be special emphasis between the terms "Schusse vom Bord" vs. "Schusse vom See" when refering to torpedo trials and practice firing. Has anyone come across any/all of these terms before in their studies/reading?

Also, does anyone have a good source that explains German naval ranks/abbreviations? Specifically the technical side, for example the abbreviations "T.W.L." "T.W.O." (Torpedowachtoffizier??), etc.

Also, I need a good source detailing the layout of the German Seekriegsleitung, especially the branches focusing on torpedos. Not just the primary organs but also the individual departments and their designation. For example TWa, m.Wa, GKds, TAm, etc.

Thanks very much ahead of time!

David]]> David Wright Technology and Operations Wed, 01 Apr 2009 23:32:33 +0200 http://www.uboat.net/forums/read.php?20,79909,79909#msg-79909 http://www.uboat.net/forums/read.php?20,79909,79909#msg-79909 ORDCONconsulting Technology and Operations Tue, 24 Mar 2009 22:23:26 +0100 http://www.uboat.net/forums/read.php?20,79853,79853#msg-79853 http://www.uboat.net/forums/read.php?20,79853,79853#msg-79853
As far as I can tell:

A. Forward Torpedo Room
- 4 torpedoes in the tubes
- 4 torpedoes underneath the deck plates
- 2 in the bunk space ? Where exactly were these stored? Did they prevent access to tubes III and IV, and the torpedoes inside them ?

B. Aft Torpedo Room
- 1 torpedo in tube V
- 1 torpedo under the deck plates in the motor room

C. External storage
- 1 torpedo on fore deck
- 1 torpedo on aft deck

Can anyone confirm this and answer my questions?

Thanks,

Dan]]> elanaiba Technology and Operations Fri, 03 Apr 2009 15:37:08 +0200 http://www.uboat.net/forums/read.php?20,79838,79838#msg-79838 http://www.uboat.net/forums/read.php?20,79838,79838#msg-79838
I received a suposed Kriegsmarine TZR Geber recently

TZR Geber
Schlü mit Schado

don´t know what this means: "Schlü mit Schado". I found a TZR Geber associated to the U 995 control room periscope.

thanks in advance for any help

the pictures are here
[ag727.vox.com]]]> Alex Technology and Operations Wed, 25 Mar 2009 19:57:12 +0100 http://www.uboat.net/forums/read.php?20,79641,79641#msg-79641 http://www.uboat.net/forums/read.php?20,79641,79641#msg-79641 General descripion is that: MWM engines were used for cruising, thus enabling main MAN engines to drive electric motors as generators to recharge batteries.
As I look on blueprints, I see these MWM engines are in set with some kind of generators and are not connected to main propeler shafts.
MAN engines and SSW motors are connected to shafts (through clutches).
And now - how it all together works? I think cruise mode is some kind of indirect, diesel/electric drive. MWM engines with their generators provide power to drive electric motors. But how these motors can act as generators powered by main MAN engines to recharge batteries? Unless in that mode only one motor drives the boat, and the other recharges batteries.
I hope I clearly expressed my doubts.

--
Thanks, regards
Maciek]]> SnakeDoc Technology and Operations Wed, 25 Feb 2009 20:05:31 +0100 http://www.uboat.net/forums/read.php?20,79640,79640#msg-79640 http://www.uboat.net/forums/read.php?20,79640,79640#msg-79640
Regards....West]]> west Technology and Operations Sat, 28 Feb 2009 05:06:02 +0100 http://www.uboat.net/forums/read.php?20,79577,79577#msg-79577 http://www.uboat.net/forums/read.php?20,79577,79577#msg-79577 Mark Technology and Operations Thu, 21 May 2009 01:51:01 +0200 http://www.uboat.net/forums/read.php?20,79514,79514#msg-79514 http://www.uboat.net/forums/read.php?20,79514,79514#msg-79514 I have been given an adjustable spanner,which i have been told is from a U-boat tool kit.
Instead of the screw method of adjustment,it has 13 shims on the jaw to fit the different sizenut/bolt.
Stamped on the handle is the name "HUF" in an inverted horse shoe,with PATENT HUBER #1 below.It also has MADE IN GERMANY stamped on it,but is this normally in English if it's made during the war?
Photo's can be supplied if required.
I'd be interested in any information supplied.
reagrds,
Martin.]]> navrady Technology and Operations Thu, 28 May 2009 19:09:18 +0200 http://www.uboat.net/forums/read.php?20,79331,79331#msg-79331 http://www.uboat.net/forums/read.php?20,79331,79331#msg-79331
I am currently researching the difficulties the Kriegsmarine had with their torpedoes early in the war and their efforts to correct them. There a couple of terms I dont get, like “Scharfschüsse” and "Nachschuss". The literal translation of "sharp shot" or "near shot" dosnt tell me very much, but Konteradmiral Wehr of the TVA constantly mentions these terms when describing the types of test firings that were done so I figure its quite important to know exactly what they mean. Any help greatly appreciated. Also, anyone know what the unit of measurement Sm/h is for - as in "bei einer strömung von 30 Sm/h?" Thanks.]]> GSU Grad Student Technology and Operations Thu, 29 Jan 2009 20:21:40 +0100 http://www.uboat.net/forums/read.php?20,79305,79305#msg-79305 http://www.uboat.net/forums/read.php?20,79305,79305#msg-79305 Oxullop Technology and Operations Thu, 19 Mar 2009 23:09:09 +0100