Tores mailbox VIIC and VIIC/41 operation and technical details

[SG]

Tore,
on this page there's a list of transmitters n receivers employed on u-boats:
http://www.uboatarchive.net/KTBNotesCommunications.htm
can you recall which ones (transmitter+receiver) among them were aboard the Kaura?
Had KNM Kaura the original german radio sets changed for some more updated post-war versions or still retained the original german radios?
Thanks a lot in advance and.. HAPPY EASTER!

[tore]

SG.
Sorry I have been off line for some 9 days and not able to respond. Unfortunately I don`t know anything about the radiotransmitter and receiver on the VIICs as it was not within my responsibility and usually the radiopeople wasn`t too happy to have any visitors. Generally our communication was fully intergrated in the Nato system and I should guess our equipment was adapted to that postwar system. During long voyages submerged we had to report at given hours by to a central Natostation Rugby by extreme longwave signals. We got signals as well from this station.

[SG]

No worries Tore, i've been logged off for a few days too. Thanks for the information anyway, although incomplete it's undoubtedly a great piece of information!
Cheers

[Don Prince]

Gentlemen,


I have been reading through the post on this site subject matter and I believe I can learn a great deal.  I may post questions later if you don't object to answering some basic questions about the Type VII C...


Kind regards,
Don_

[tore]

Don.
Shoot! Basic questions or not. I`ll be happy to answer if I can.
Tore

[Don Prince]

Hello Mr. Tore,


I am in the process of setting up the Skizzenbuch for the VIIC U-Boat in a 11 x 17 leather post binder.  I have the basic outline for the manual in MS Word.  However, I find it very difficult to read the schematics so graciously provided by Captain Jerry Mason on the uboatarchive.net web site.  It's almost impossible to determine pipe line colors on the black and white copies of the original German documents.  I don't know where I found Plate17 and Plate 27 that are a light tan color and you can see the color striping on the pipes.  In addition, you can tell that when a pipe crosses another that it is not a junction.  Does anyone know where the source for those documents came from and is it possible to get the full set.  I am only having "Staples" to print one copy for my own personal library and the leather post binder is very expensive ($230.00).


I understand the Negative Buoyancy Tank is vented internally through a muffler when it is being flooded in a surface maneuver.  Are there photos pointing to the control device (Valve) and the muffler in the control room?  I believe I would like to add photos of things like that to my Skizzenbuch. 


Regards,
Don_

[tore]

Don.
I am not sure I fully understand your questions correctly. However most of the systemsketches provided on the net derive from the instructionmanuals of U 570 captured by the British in Iceland September 1941, thus the system sketches are not always 100% up to date with the executions of late war VIICs. The drawings are pretty much the same as we used onboard. However  some sketches have been coloured and adjusted by different people (crew?) and some mistakes are introduced. Thus there are no sketch valid for all the VIICs allthough basically the principal  system are the same. I suggest you chose which " VIIC vintage" you would go for and we discuss each system separately and hopefully I can answer your questions. In order to make it a bit simpler I answere your first question in a separate post.
Tore

[tore]

Don.
Untertriebzelle system.
Yes, the venting mufflers and pipes  are fitted on the aft part of the attackperiscope casing. See photo below, a photo of the mufflers situated down in the bilge follows I just have to find it.
Tore

[tore]

Don.
I finally found one of  Falos execellent photos and put up a few arrows showing the system.
Tore

[Don Prince]

Hello Mr. Tore,
Thank you for the information and the photos...  The photo labeled Q Tank Muffler explains a lot and I have a few questions regarding that photo and Plate 7 from the Skizzenbuch.
The Negative Buoyancy Tank side of Plate 7
1.  There are 3 muffler (k) in the drawing on Plate 7
Q1 - Is there only 1 muffler as indicated in the Q Tank Muffler photo?
2.  Plate 7 shows 3 valves on the Negative Buoyancy vent line; a valve near each tank and one valve near the muffler (no glass viewing eye). 
However, the Q Tank Muffler Photo suggests there is a separate line from each Negative Buoyancy tank which has a valve and a glass viewing eye.  These two vent lines are joined at a “Y” connection and vent through the muffler into the internal pressure hull.
Q2.  Are my observations correct?
Q2-1.  On Plate 7, should the valve (h) going to the muffler (k) be a glass viewing eye instead of a valve?  This would make Plate 7 closer to the actual piping.  Unless there are actually 4 valves; 2 near the Negative Buoyancy tanks and 2 near the muffler?  The Plate 7 just doesn’t match the Q Tank Muffler photo… 
3.  The Q Tank Muffler photo has 4 valves and 4 glass viewing devices feeding into the one muffler.  I assume 2 lines for venting from Negative Buoyancy tanks and two lines for venting from the Regulating tanks and Bunkers. 

Q3.  Am I correct?

Q3-1.  Looking at the Q Tank Muffler photo  -  from left to right; which valve controls what?

Regards.
Don_

[Don Prince]

Hello Mr. Tore,


One of the photos you sent was of Plate 17 and the lines to blow the Negative Buoyancy Tank.  However, when I look at the 2 different Plate 17 prints that I have there is a difference.  There is an extra valve going to the Negative buoyancy tank???


I will attempt to upload the two images later...


Regards,
Don_

[Don Prince]

Here is the different Plate 17 with the extra valve at the Negative Buoyancy Tanks...


Opinion?


Regards,
Don_

[tore]

Hello Mr. Tore,
Thank you for the information and the photos...  The photo labeled Q Tank Muffler explains a lot and I have a few questions regarding that photo and Plate 7 from the Skizzenbuch.
The Negative Buoyancy Tank side of Plate 7
1.  There are 3 muffler (k) in the drawing on Plate 7
Q1 - Is there only 1 muffler as indicated in the Q Tank Muffler photo?
2.  Plate 7 shows 3 valves on the Negative Buoyancy vent line; a valve near each tank and one valve near the muffler (no glass viewing eye). 
However, the Q Tank Muffler Photo suggests there is a separate line from each Negative Buoyancy tank which has a valve and a glass viewing eye.  These two vent lines are joined at a “Y” connection and vent through the muffler into the internal pressure hull.
Q2.  Are my observations correct?
Q2-1.  On Plate 7, should the valve (h) going to the muffler (k) be a glass viewing eye instead of a valve?  This would make Plate 7 closer to the actual piping.  Unless there are actually 4 valves; 2 near the Negative Buoyancy tanks and 2 near the muffler?  The Plate 7 just doesn’t match the Q Tank Muffler photo… 
3.  The Q Tank Muffler photo has 4 valves and 4 glass viewing devices feeding into the one muffler.  I assume 2 lines for venting from Negative Buoyancy tanks and two lines for venting from the Regulating tanks and Bunkers. 

Q3.  Am I correct?

Q3-1.  Looking at the Q Tank Muffler photo  -  from left to right; which valve controls what?

Regards.
Don_

Don.
I am sorry to confuse you as I introduced the inboard venting and muffler for the FO regulating tanks 1 and 2 port and stb. This has nothing to do with the venting of the Untertriebtank. Thus a number of your questions are based on my mistake. I am afraid the venting of the Untertriebtank is  a bit more difficult to show on a photo, but as these tanks never are used for fuel there are no sightglasses, they have Kingstones and thus they have a pressure hullvalve ( valve near the tank). The Kingstones and vents are operated from the forward end of the CR and there is a common muffler  probably situated under the floorplates. I cannot recall the exact position of the Kingstones and inboard vent pipes, but have indicated on the photo were I believe they are. The Kingstones are operated by removable handles so you only see the valvestem. Back to the questions on the FO regelzelle. Contrary to the drawing the system is connected to one muffler. As to the sightglasses, only tanks which can carry fuel are equipped with sightglasses and the piping is slightly deviating from the drawing which is normal.  On the photo I have indicated my assumption of the system, if something is unclear just ask.
Tore

[tore]

Don.
Blowingsystem of the Q-tank (neg. Tauchzelle).
The two system plans 17 and 17b are indeed different. The plan 17 system is using a dualsystem, the inboard venting pipe act as a blowingpipe as well, connectionbranch marked Drueckluftanschluss (pressure airconnection).  The connection to the Q tank is via an ordinary hullvalve. The system 17b has a separate blowingair pipe no connection to a ventingpipe and is entering the Q tank via a checkvalve and an ordinary hullvalve, eg. two valves. Plan 17b is new to me, do you happen to know the year it was made? I have a feeling it could be later than  1941. It should be a drawing of the inboard venting from the same year which give an better explanation of the system.
Tore

[tore]

Don.
Further to my to days post I assume the arrangement for the Q tank venting-blowing on the U 995 is as follows. Your system 17b is a newer version of the plan 17 possibly introduced in 1943 and indeed installed on U 995. The piping is located forward part, port and starboard of the CR. On the photo below you`ll see the venting having a hullvalve and a second valve. On the photo of the stb hullvalve you `ll see they have exchanged the T handle with the inboard valvehandle a common thing on the museum U-995. The ventpipe on starboard goes up and cross over to port side  where it goes behind the electronic boxes and down to the muffler under the flooring. The port ventpipe goes down behind the the same boxes as well and joins the stb pipe prior to the muffler. Next to the ventpipe is the blowing air hullvalve, having a round handwheel with a ball. This valve has a checkvalve in the same housing as can been seen on the photo. To sum up, there are double hull ventingvalves on the ventingpipe,no connection to the blowingair pipe and a separate blowingpipe having a double hull valve of which one is a checkvalve.This should match very well with your systemsketch 17b and possibly for most of the VIICs built from 1943, so take your pick which vintage you`ll go for.