Tores mailbox VIIC and VIIC/41 operation and technical details

[NZSnowman]

Simon
Floorplates.
I really can`t remember excactly, howewer I believe they were of different sizes but could be handled by one man.
Tore

This is what I was thinking This would make the must sense. I will workout the sizes of the plates base on that valves below them.

[NZSnowman]

Simon.
One leap ahead.   On port side is a pipe ( yellow on the photo below) going vertically from below the exhaustmanifold up to the top following the pressurehull all the way to starboard side where it enters the heatexchanger via a valve. I assume this must be the yellow pipe on the systemsketch below. Again I assume somewhere underneath the exhaustmanifold there would be a connection via  to the enginedrive cooling waterpump via a valve.
Tore

Tore, is the heat exchanger in U-995 original German? As I have never seen anything like this in any war-time photo's.

Simon.
One leap ahead.   On port side is a pipe ( yellow on the photo below) going vertically from below the exhaustmanifold up to the top following the pressurehull all the way to starboard side where it enters the heatexchanger via a valve. I assume this must be the yellow pipe on the systemsketch below. Again I assume somewhere underneath the exhaustmanifold there would be a connection via  to the enginedrive cooling waterpump via a valve.
Tore

Tore, is the heat exchanger in U-995 original German? As I have never seen anything like this in any war-time photo's.

Simon
Heathexchanger.
I believe it is the original. It is really a straight forward oldfashioned tube heatexchanger  not the modern plate exchanger used today.
Tore

Tore, I started relooking at the heat exchanger, and something does not add up. I believe the heat exchanger is original but it not in its original location.
 
If we look at a few things:

• The current location of the heat exchanger look messy to me, it not the normal good German engineering we see throughout the boat.
• We can see a copper pipe, and we know that there is no original copper piping in the engine room.
• The red handle looks recent and not an old German style.
• The valve itself also looks recent not an old German style.
• The layout of the current piping to the heat exchanger also look not like the normal German engineering we see throughout the boat. Why did they run the piping up the pressure hull over the flooring and then back down. This is almost the longest distance to get to the heat exchanger. Why did they not just run the piping under the floor like all the other pipes

[tore]

Simon.
You are touching upon something which for long has been in the back of my mind.
1.  I cannot remember this arrangement. Well that doesn`t mean too much.
2.  If you remember in June we had a discussion, Maciek, Christopher, you and me about the purifier and the horizontal port small circulatingpump not shown on any 
     pipescheme we couldn't`t figure out  what was the use of the pump.
3.  I launched the idea it was installed later even after my time.
If you add that up to your new ideas and include that this pump is indeed connected to the strange crossover to the starboard heatexchanger I believe we are on a track worth while to follow.
I`ll check further details today on that theory.
Tore
           

[SnakeDoc]

Hi Gents

U 864 type IXD2.

For those who might be interested. The Norwegian authorities has estimated the cost of rising the submarine to be approximately 1.5 billion NOK equivalent to US

[tore]

Maciek.
U 864 final days is a fascinating story illustrating the last hard times of the german submarine service at the end of WW2. Books are written on the subject.
She left Kiel just after  having schnorkel installed, ran aground in Norway, was bombed in the submarine pen in Bergen while repairing and was training the crew on schnorkeling just along the south western coast of Norway prior to departure for Japan. During those trials one of her engine started to misfire and they decided to return to Bergen for repairs. At that moment the hydrophone operator of HMS Venturer, which had been despatched for a hunt on U 864, heard some funny engine noises which he mistook for a semidiesel of a fishingvessel. U 864 apparently navigated too long by the periscope and was spotted by HMS Venturer. U 864 realizing they were spotted started to zigzag. HMS Venturer decided to fire her 4 torpedoes programming it for a 3 D pattern fairly unproven. U 864 heard the torpedoes were launched stop schnorkeling and went deep, avoiding 3 of the torpedoes, howewer the 4th had a hit  and U 864 imploded. It is claimed to be the first sinking of a submerged submarine by another submerged submarine ever. There are better and more accurate reports on the net, this only a brief incomplete story based on my memory.
Tore

[tore]

Simon.
I am almost convinced the heatexchanger and port circulationpump is a modification possibly made after my time. I guess the handle of the water handpump was a modification which was necessary as the wooden handle came in conflict with the vertical copperpipe. We still haven`t localized the luboil purifier which is supposed to be hooked up to the heatexchanger. It is all very odd. I`m busy with the details of the coolingwater/ luboil system under the floorplates and shall possibly need a couple of days before I have some details on the subject.
Tore

[NZSnowman]

Simon.
I am almost convinced the heatexchanger and port circulationpump is a modification possibly made after my time. I guess the handle of the water handpump was a modification which was necessary as the wooden handle came in conflict with the vertical copperpipe. We still haven`t localized the luboil purifier which is supposed to be hooked up to the heatexchanger. It all very odd. I`m busy with the details of the coolingwater/ luboil system under the floorplates and shall possibly need a couple of days before I have some details on the subject.
Tore

Yes, very odd!!!

I am working on the exhaust cooling water outlet this morning trying to track it as far as possible.

[NZSnowman]

Tore, what does this handle open?

[NZSnowman]

Tore, good news This morning I was able workout one more original arrangement for the Cooling Water System. I was able to add the line between the diesel engine and LO Cooler. I am yet to locate the pressure gage or thermometer.

I have also added the Relief valves, the lines to the Relief valve and funnels. Did you noted that the Relief valves at not in the same locates on the port and starboard side.


Fig. 1. Cooling Water System.


Fig. 2. I love pipes 

[SnakeDoc]

Hi Simon

Tore, what does this handle open?

It looks like handle for remote operation of the valve in the fuel line.


--
Regards
Maciek

[tore]

Tore, what does this handle open?

It looks like handle for remote operation of the valve in the fuel line.


--
Regards
Maciek

Simon.
I guess you found the handle for the shut off valve of the return cooling water from the starboard exhaustmanifold.    Maciek is of course right the handle has a fuelvalve shape, but there are no fuel oilpipes in this area and as we have seen before handles have been mixed. The excellent photo of Maciek shows a valve and a pipe located where the coolingwater return bend should be. As far as I can see, you`ll not find this extension on the port side, you find a similar valve at the end of the pipe leading to the strange port circulationpump . I guess this support of theory that the circulation system has been cut in the original system and installed later.
Tore

[SnakeDoc]

Tore,

U 864 final days is a fascinating story illustrating the last hard times of the german submarine service at the end of WW2. Books are written on the subject.
[...]
U 864 apparently navigated too long by the periscope and was spotted by HMS Venturer. U 864 realizing they were spotted started to zigzag. HMS Venturer decided to fire her 4 torpedoes programming it for a 3 D pattern fairly unproven. U 864 heard the torpedoes were launched stop schnorkeling and went deep, avoiding 3 of the torpedoes, howewer the 4th had a hit  and U 864 imploded.

Well, there are a lot of books written based on post-action reports. But these are taken without any criticism. For example, almost everyone say, that U864 was spotted becuase of exposed periscope (at distance 3200 yds = 2900 m !). Most likely, first was spotted snorkel head. There is also said, that commander of U864 realized, that he is followed by enemy and started to make these slight zig-zags (about 10 deg at each side) - would the commander take such action instead of switching electric motors and going below periscope depth? I would rather say, U864 was going with zig-zag course, and that the zig-zag pattern was recognized after some time of plotting. I also doubt about evasive maneuver - I don't think that hydrophone operator was able to hear incoming torpedoes while snorkeling.
Interestind discussion can be found here:
http://www.rnsubs.co.uk/Community/Forum/index.php/topic,3564.0.html


--
Regards
Maciek

[NZSnowman]

Tore, what does this handle open?

It looks like handle for remote operation of the valve in the fuel line.


--
Regards
Maciek

Simon.
I guess you found the handle for the shut off valve of the return cooling water from the starboard exhaustmanifold.    Maciek is of course right the handle has a fuelvalve shape, but there are no fuel oilpipes in this area and as we have seen before handles have been mixed. The excellent photo of Maciek shows a valve and a pipe located where the coolingwater return bend should be. As far as I can see, you`ll not find this extension on the port side, you find a similar valve at the end of the pipe leading to the strange port circulationpump . I guess this support of theory that the circulation system has been cut in the original system and installed later.
Tore

Thanks Maciek for the great photo!
 
Tore, I have a photo of the handle from the other side. I am also happy that you think this is the shut off valve of the return cooling water from the starboard exhaust manifold, as I was hoping it was.

[tore]

Maciek.
I just had a brief look at Community Forum and are astonished about what people know and discuss. I agree there are a lot of details which don`t match in all the stories on U 864. The basic is the U 864 had a schnorchel installed just before she left the yard in Germany. They spent 4 days sailing to Norway included grounding in Farsund area. She was in the Bergen submarine pen during an air raid where dambusters were used, one penetrated the roof. Just after the bergenrepair they decided to train the crew in schnorcheling prior to the departure to Japan, thus inexperienced crew doing exercises on schnorchelling off the Norwegian coast. I agree that the schnorchel mast is the first thing to be spotted rather than periscope. The theory on seasickness and zig zacking while schnorchelling I have never heard of. The talks and theories about supercharger is  strange and not worth to comment.
I guess U 864 was exercising the inexperienced crew on schnorchelling, the noise picked up by the sonar of HMS Venturer, probably not experienced in diesel sound while training schnorchelling ( they would not use the engine with a failure). They had decided to return to Bergen for engine repair. The supercharger should not be used while schnorchelling. I believe they had stopped schnorchelling, still submerged switched to E-motors, took the usual sweep by the sonar and realised they were spotted started zigzagging heard the torpedoes were coming and  crash dived deep. This is my theory, but take it with a grain of salt, I have not read any reports on the sinking.
Tore

[tore]

Simon.
Another leap  ahead, but a lot to go. Progressing every day.
Tore