VIIC "On the Ways"

[TopherVIIC]

Hey folks...
As a change of pace, and to make her look less skeletal in the bows, I have a question.



I see this deck stowage box listed on every drawing I have of type VIIC and VIIC/41, and I see it referenced in a rough sort of way from the front looking aft in the drawing of Frame#106 from "Anatomy..." (The dwg is of #106, but shows the ghost of the box behind it.)
This box butts up on its aft end with the solid bulkhead at frame#102. It sits on the port side only, as to Stbd fixed to the bulkhead @ #102 is the valve and mechanism for the bow buoyancy tank.
(edits to fix wrong frame ref - sorry! :-) )

I would like to know more of how it is constructed, and how it is accessed from the deck.





It seems to me that this box, the anchor chain and hawse are inter-related, and possibly go through this box.


I would like to know how this happens! :-)
Do any of you have pics or refs that show more?
I would like to build the model with this deck hatch open, as we all know that open deck hatches make cooler toys to look at! ;-)


Secondary question - the row of small round drainage holes in that area of the bows and the structural work that supports the steel part of the casing on both the Atlantic and regular bow...


I assume those holes sit above the Bow buoyancy tank, or are somehow sep. from it, but that whole construction is puzzling.


Trying to construct the frames, the bow supports, our little Deck storage box, the bow buoyancy tank, those little drain holes and the towhook well, it is making me scratch my head a little!
It is funny, because till you try to draw that area of the ship, and then try to build it in miniature, one is easily tricked into thinking that part will be easy.


Thanks from a lightly stranded modeler!
Cheers
Christopher

[NZSnowman]

Secondary question - the row of small round drainage holes in that area of the bows and the structural work that supports the steel part of the casing on both the Atlantic and regular bow...

I assume those holes sit above the Bow buoyancy tank, or are somehow sep. from it, but that whole construction is puzzling.

I believe is this the correct profile for the Bow Buoyancy Tank but check with Maciek as his drawing does not match my http://www.ubootwaffe.pl/okrety/wyposazenie/zbiorniki-okretowe.html
 

... it is making me scratch my head a little!
It is funny, because till you try to draw that area of the ship, and then try to build it in miniature, one is easily tricked into thinking that part will be easy.

I have come to believe this part of the boat is one of the must complex parts of the boat. I have been working on my bow for about 3 years now I have found it better to go back to the stern and understand how that works, so I can workout the bow.

[TopherVIIC]

I have come to believe this part of the boat is one of the must complex parts of the boat.

I agree with you ENTIRELY on that!


I am pretty much on the same page with you as far as the general formation of the bow buoyancy tank.
Minor differences - but ones we could not share a beer over!


On your drawing, where the fwd top of the tank meets the tow hook well is lower by a few real cm than mine, but I may be wrong. Purple dashed line on mine)
I have the girders supporting the Atlantic deck a little more sturdy towards the aft end near the vent and the back of the tank, but again I may be wrong.


I have seen Maciek's tanks, and I interpret my references I have slightly differently from him too - tho again I may be wrong. That's ok - more beer to talk it out!





The main question I have is about the placement of the 12 diagonal drain holes (black circles on my dwg) properly placed? That would make sense to me, if my tank is right. It would allow water to drain off the top of the tank, regardless of the open or closed state of the tank, and would also allow air in and out of the tow hook well, which I would bet money that it has drain holes on its forward most bulkhead. That part is pure speculation, of course, pending further research.


I also have questions as stated about the stowage bin on the port side. (Lighter orange on my drawing) I am not sure if you thought I meant the limber holes under the atlantic bow top, but the I meant the 12 diagonal holes visible from outside the boat.


Thanks for your help - I can see we are going to communicate frequently between us about the drawings!
Cheers
Christopher

[NZSnowman]

The different maybe in the different bows. There could be three different dimensions for the Type VIIC

[TopherVIIC]

The placement of your twelve diagonal holes makes sense and you probably took it from better reference than I took mine, so I will probably change my drawing. Thanks! :-)
It is closer to the deck than I thought it was!
Now if I can just figure out the stowage box, and how it ties in with the anchor hawse and the chain that i believe passes through it.
For some reason my drawing did not load earlier, but it it posted now.


I would be interested in seeing the pic of U-250 you used for the engine work - I am thinking of aiming towards that boat. I know it was a VIIC not a VIIC/41, but at this point I can change my model.
Cheers
Christopher

[tore]

Hi both of you
I`m not going to interfere in you very detailed discussion on a subject where you have more expertise than me, but I`m posting my detailed photo of  KNM Kaura`s (ex U 995) atlantic bow at the time she was untouched by the museumspeople in Germany. I`m not sure if it can be of any help though.
Regards Tore

[TopherVIIC]

Hi both of you
I`m not going to interfere in you very detailed discussion on a subject where you have more expertise than me, but I`m posting my detailed photo of  KNM Kaura`s (ex U 995) atlantic bow at the time she was untouched by the museumspeople in Germany. I`m not sure if it can be of any help though.
Regards Tore

Tore!
Hello! You are not interfering Sir! We are simply trying to sort out technical details in an area with little information! Every new photo or drawing we can get helps! Again - Thank you for your contributions! Join in any time!


May I ask How deep was that fjord? :-)

Christopher

[tore]

Hi both of you
I`m not going to interfere in you very detailed discussion on a subject where you have more expertise than me, but I`m posting my detailed photo of  KNM Kaura`s (ex U 995) atlantic bow at the time she was untouched by the museumspeople in Germany. I`m not sure if it can be of any help though.
Regards Tore

Tore!
Hello! You are not interfering Sir! We are simply trying to sort out technical details in an area with little information! Every new photo or drawing we can get helps! Again - Thank you for your contributions! Join in any time!


May I ask How deep was that fjord? :-)

Christopher

Hi Christopher!
This particular fjord up in northern Norway is called the Trollfjord and is more known for the narrow entrance rather than depth . But in general the depth of the fjords are max 1000 m. The depth of the fjords together with icywaterivers from the glaciers made it an excellent hide for the submarines. The difference in temperature and salinity made waterlayers which created a "reflectionmirror" for the sonar and you could registered the different layers by sensors. When you found a proper layer you placed the sub rigth underneath and shut off all motors so everything was dead silent. The trim could be kept by lowering and raising the periscopes into the other density layer using the accumulated hydraulic pressure,( no sound).
This was the ultimate excersise for CO`s of a submarine and many of us were convinced that the numerous observations of foreign submarines in our fjords were ideed foreign subs training CO`s  for this such operations.
regards Tore

[NZSnowman]

Hi both of you
I`m not going to interfere in you very detailed discussion on a subject where you have more expertise than me, but I`m posting my detailed photo of  KNM Kaura`s (ex U 995) atlantic bow at the time she was untouched by the museumspeople in Germany. I`m not sure if it can be of any help though.
Regards Tore

Tore!
Hello! You are not interfering Sir! We are simply trying to sort out technical details in an area with little information! Every new photo or drawing we can get helps! Again - Thank you for your contributions! Join in any time!


May I ask How deep was that fjord? :-)

Christopher

Hi Christopher!
This particular fjord up in northern Norway is called the Trollfjord and is more known for the narrow entrance rather than depth . But in general the depth of the fjords are max 1000 m. The depth of the fjords together with icywaterivers from the glaciers made it an excellent hide for the submarines. The difference in temperature and salinity made waterlayers which created a "reflectionmirror" for the sonar and you could registered the different layers by sensors. When you found a proper layer you placed the sub rigth underneath and shut off all motors so everything was dead silent. The trim could be kept by lowering and raising the periscopes into the other density layer using the accumulated hydraulic pressure,( no sound).
This was the ultimate excersise for CO`s of a submarine and many of us were convinced that the numerous observations of foreign submarines in our fjords were ideed foreign subs training CO`s  for this such operations.
regards Tore

I must say it was the first time I was more delighted to see a landscape than a Type VIIC The fjord look very similar to NZ Fiordland.

Also very cool about how to keep the trim with the periscopes!

[tore]

Hi both of you
I`m not going to interfere in you very detailed discussion on a subject where you have more expertise than me, but I`m posting my detailed photo of  KNM Kaura`s (ex U 995) atlantic bow at the time she was untouched by the museumspeople in Germany. I`m not sure if it can be of any help though.
Regards Tore

Tore!
Hello! You are not interfering Sir! We are simply trying to sort out technical details in an area with little information! Every new photo or drawing we can get helps! Again - Thank you for your contributions! Join in any time!


May I ask How deep was that fjord? :-)

Christopher

Hi Christopher!
This particular fjord up in northern Norway is called the Trollfjord and is more known for the narrow entrance rather than depth . But in general the depth of the fjords are max 1000 m. The depth of the fjords together with icywaterivers from the glaciers made it an excellent hide for the submarines. The difference in temperature and salinity made waterlayers which created a "reflectionmirror" for the sonar and you could registered the different layers by sensors. When you found a proper layer you placed the sub rigth underneath and shut off all motors so everything was dead silent. The trim could be kept by lowering and raising the periscopes into the other density layer using the accumulated hydraulic pressure,( no sound).
This was the ultimate excersise for CO`s of a submarine and many of us were convinced that the numerous observations of foreign submarines in our fjords were ideed foreign subs training CO`s  for this such operations.
regards Tore

I must say it was the first time I was more delighted to see a landscape than a Type VIIC The fjord look very similar to NZ Fiordland.

Also very cool about how to keep the trim with the periscopes!

HiNZSnoWman.
I guess is that is probably why you call it Fjordland, we call Norway the land of fjords. The major difference though is that most of it is above the polar circle and during the cold war year a little too close to the related activities.
regard Tore

[TopherVIIC]

Tore
I became a scuba Dive Master probably 20 years ago, and there was a point where I was "wet" more than I was dry in my life.
I have dived in tropical waters and cold waters, deep and shallow, and in all kinds of weather.
One of the things that I think a lot of people do not realize is what those salinity layers are, and how effective they can be.
One of the more interesting places to dive for me was where the South China Sea meets the Pacific. Two different types of water, and it was such that you could, just like a submarine, achieve neutral buoyancy and stick your hand in and out of salinity layers that may have been many degrees different. You could FEEL your hand cold, while your body was in quite warm water.


We did not have onboard Salinity Meters but you could sometimes see with your eyes water that seemed "thicker" - sometimes with more brine or plankton. Your hand could feel different temps of water.
It makes me smile to think that you trimmed the boat in silent running mode with the periscope and accumulated hydraulic pressure. Not only would the trim be affected by the mere physical extension and displacement of center, but one would think that moving a column of air that is inside the tube higher or deeper would affect buoyancy by its expansion and compression. Even a few meters of change can affect the volume of gas.


Cheers Sir!
Christopher

[NZSnowman]

... and there was a point where I was "wet" more than I was dry in my life ...

Christopher, I am similar to you! I have spend more time in the snow, dealing with avalanches than I spend on a beach Spend the last 23 years working with avalanches.

In fact if I think about it, I have been caught in more avalanches than days spend at sea 
 

[NZSnowman]

I guess is that is probably why you call it Fjordland, we call Norway the land of fjords. The major difference though is that most of it is above the polar circle and during the cold war year a little too close to the related activities.
regard Tore

I think a big different between the Norway and New Zealand fjords is the rainfall, we have extreme rainfall (between 8 m to 15 m a year).  I live only about 60 km away from a place that get between 18 to 20 m of rain a year but where I live we only get about 2 m a year
 

[TopherVIIC]

In fact if I think about it, I have been caught in more avalanches than days spend at sea  :-) :-) 

Simon - I hear ya!!!
Me - I am not fond of snow, though I did do a few winters near the North Korean border, in tents and arctic boots.
And I live in Buffalo.
While we will go anywhere we need to, in general I think Marines are most fond of the water that is somewhat liquid! :-) :-D

[tore]

Tore
I became a scuba Dive Master probably 20 years ago, and there was a point where I was "wet" more than I was dry in my life.
I have dived in tropical waters and cold waters, deep and shallow, and in all kinds of weather.
One of the things that I think a lot of people do not realize is what those salinity layers are, and how effective they can be.
One of the more interesting places to dive for me was where the South China Sea meets the Pacific. Two different types of water, and it was such that you could, just like a submarine, achieve neutral buoyancy and stick your hand in and out of salinity layers that may have been many degrees different. You could FEEL your hand cold, while your body was in quite warm water.


We did not have onboard Salinity Meters but you could sometimes see with your eyes water that seemed "thicker" - sometimes with more brine or plankton. Your hand could feel different temps of water.
It makes me smile to think that you trimmed the boat in silent running mode with the periscope and accumulated hydraulic pressure. Not only would the trim be affected by the mere physical extension and displacement of center, but one would think that moving a column of air that is inside the tube higher or deeper would affect buoyancy by its expansion and compression. Even a few meters of change can affect the volume of gas.


Cheers Sir!
Christopher

Rigth you are Christpoher. Deligthed to hear you are, I presume, a PADI divemaster. I myself got my first diving certificate in the pioneer times 1953 ( thru the navy) and the in the certificate I was registered as "shallow water diver" you would laugh today if you saw the equipment. Since then I renewed the certficates both as PADI advanced open water diver as well as CMAS. Apart from diving all along the Norwegian coast, I did (together with my wife) a lot of diving in the Maldives, Red sea, and Caribbean. My biggest hobby (and most expensive) was underwater movies and we were hopping around the world with 32 kgs of equipment  the excessive luggagecost was substantial. But you are rigth, you could as a scubadiver literally see "rivers" of water with different temperatur and salinity. Not so onboard the subs, it was sensors attached to long cables able to take readings at quite a distance. When the sub was in neutral boyancy you could ballance her at your fingertip (a small exaggeration),but as an example, we were 46 men onboard an prior to the claxon sounding for divingstations the officer on watch ordered: pump 400 liters from forward trimtank to aft to compensate for the movement of the men. I was usually already on my way to the controlroom at that order. So the the good old VIIC was ticklish but with some speed you could hold her within limits by the hydroplanes