Author Topic: Tores mailbox IX C and IX C/40 operational and technical details (Read 45521 times)

Rokket · « **on:** 31 Jul , 2016, 02:03 »

A new, extra Tore's Mailbox for IX C and IX C/40 operational and technical details

tore · « **Reply #1 on:** 31 Jul , 2016, 03:37 »

I hope we shall have an interesting discussion around the difference between the two types VIIC and IXC, and welcome Dons input.
Allthough the IX type was developed simuntaneously with the VII type both having roots back to the WW1 submarines, they were designed for different purposes, type IXC being the long distant counterpart to the medium range VIIC and the command boat for the wolfpackleader. In addition some of the IXs was in the latter part of WW2 converted as supply boats,"Milchkuhes" for the VIICs.
The IXCs had one more torpedotube than the VIICs but I guess the VIICs was a better attack boat as the divingtime was considerably quicker than the larger IXCs which took its toll when the allied airsuperiority became a problem.
Below is an image of a IXC moored together with a RN T class (two midship aft torpeotubes) and the RN A class originally designed for the Pacific.
Tore

Don Prince · « **Reply #2 on:** 05 Aug , 2016, 16:25 »

Hello Mr. Tore,

I am reviewing the trim system on the IXC and everything looks very familiar except for item a3 which is a change-over cock but no central passage way? I marked the item on the attached drawing. Now back to the basics:

a3 - is the change-over cock
e - is the main control valve
m - is a spring loaded pressure valve

When the pump man turns the main control valve (e) to pressurize the trim tank he can monitor the air pressure in the line when viewing the pressure gauge.

1. Is the main control valve (e) used to adjust the amount of air pressure in the line?
2. If the air pressure in the line exceeds the limit set by the pressure valve (m), then will the excess air pressure be vented into the pressure hull?

Regards,
Don_

tore · « **Reply #3 on:** 06 Aug , 2016, 02:46 »

Don.
The plan you are referring to is the LP system,practical identical to the IIVC system. As you know there are two ways of adjusting the trimsystem, normally by the trimpump or by LP air. Using the trimpump implies operating a closed system eg. the air and water volume is constant. When you pump the water to the aft tank the equivalent volume of air is replenishing the watervolume in the forward tank via the LP blow/vent pipe. In that case the LP air pipe is used as an "airshifting" pipe and the enclosed air is free flowing through a central bore of the aircock whereas the LP air connection is shut, you add nothing to the system.
If the trimming is carried out by LP air, you add air to the system as you turn the trim cock to put the required trimtank under pressure and simultaneously the other tank has to get rid of the excessive air to accommodate the receiving water and is vented via the cock and funnel to the bilge. The water is controlled by the trim valve and the water meter as normal. As you normally don`t want to change the amount of water used for trimming, you check the air cock for possible water in the funnel indicating when the receiving tank is full.
As you see, the central bore for the air cock is not drawn neither on the plan for the VIICs or IXCs, on the trimlineplan for the VIICs however you see the bore clearly marked, I assume you`ll find same on the trimline plan for the IXCs.
Tore

Don Prince · « **Reply #4 on:** 06 Aug , 2016, 19:21 »

Hello Mr. Tore,

I believe the Germans copied an error and promulgated it in their drawings... On the type VII drawings the TRIMMDRUCKLUFTSCHALTER item (g1) on the Lenz -und Trimmanl drawing looks to be the exact same device TRIMMDRUCKLUFTSCHALTER item (d2) on the Nd luftanlage drawing, but they are not drawn the same??? Both should be a change-over cock with a central passage.

Item (g1) looks to be drawn correctly... Perhaps, it was added to the Type VII drawings and missed on the Type IX drawings. I have attached the Type IX Trim drawing which does NOT have an air line going to the trim tanks...

Regards,
Don_

tore · « **Reply #5 on:** 07 Aug , 2016, 00:57 »

Don.
When you have two systems interconnected like LP system connected to the trimsystem I guess you would have a certain individual judgement as to the details you should include on the systemsketch. The people making the VIIC sketches thought it was a good idea, as I would have done, to include the equalizer line on the trimlinesystem, the IXC people was of the opinion that same line belong to the LP system. Nevertheless I am inclined to maintain the central passage in the changeover cock for both IIVC and IXC types.
Tore

Don Prince · « **Reply #6 on:** 07 Aug , 2016, 01:43 »

Hello Mr. Tore,

I agree with what you stated... The Type IX should have the change-over cock with the central passage!

Regards,
Don_

Don Prince · « **Reply #7 on:** 09 Aug , 2016, 12:57 »

Hello Mr. Tore,

I added the Trim vent line and valve to the drawing and translated the German to English on the page... Does it look OK to you?

Regards,
Don_

tore · « **Reply #8 on:** 09 Aug , 2016, 14:44 »

Don.
I guess it is OK but may be you should use the correct icon for the central passage chageover cock , a singel line instead of double.
Tore

Don Prince · « **Reply #9 on:** 09 Aug , 2016, 19:57 »

Hello Mr. Tore,

Suggestion taken and I fixed the drawing...

Regards,
Don_

Don Prince · « **Reply #10 on:** 17 Aug , 2016, 20:50 »

Hello Mr. Tore,

I got some interesting photos of U-505... I am curious about the Dive Plane control stations; it looks like the two manual control wheels are tied together by a sprocket and chain. Would that mean that if there was a power failure, then both dive planes would move in the same direction (sort of parallel to each other)? what do you thing?

Regards,
Don_

tore · « **Reply #11 on:** 18 Aug , 2016, 03:09 »

Don.
It looks indeed as the two manual hydroplane controlwheels are interconnected by chaindrive, I never saw it before. I assume the electrical push button system is unaltered and thus the dual operated system is an emergency system. Generally the forward hydroplanes are used for depthcontrol (pitch) and the aft hydroplanes for leveling, on the VIICs. This system required two operators. todays submarines combines the two, thus reducing the manning.
I am astonish to see that the IXCs emergency system of the 1940 years already got a rude version of it. The flexibility of the two man operation is gone however, but I assume a possible porpoising effect as well, interesting.
Tore

Don Prince · « **Reply #12 on:** 19 Aug , 2016, 21:10 »

Hello Mr. Tore,
Hello Mr. Tore,

Does my update to the Fuel Oil Measuring (Sounding) look OK for the Type IX C U-Boat? I had a some problems figuring out Bild 1 and Bild 2....

Regards,
Don_

Don Prince · « **Reply #13 on:** 20 Aug , 2016, 00:32 »

Hello Mr. Tore,

Can you translate this for me?

"Entwässern Entlütungsleitung bei Frostgefahr Tauchbunker 4 Stb bzw Bd"

Sheet 9 index item "f" I'm having a problem with "Frostgefahr"

Regards,
Don_

tore · « **Reply #14 on:** 20 Aug , 2016, 01:03 »

Don.
Seems to me OK. Bild 1 shows the cock in a venting position. To be sure you are not fooled by an airpocket on top of the fuel you vent the top of the tank into the boat to check before you carry out the sounding. Bild 2 has a wrong translation Lenzen does not mean pressurizing but emptying eg. Bilgepump is Lenzepump. Thus you might connect a bilge hose to the system. Otherwise I guess your understanding of the system is OK.
Tore

tore · « **Reply #15 on:** 20 Aug , 2016, 01:13 »

Quote from: Don Prince on 20 Aug , 2016, 00:32

Hello Mr. Tore,

Can you translate this for me?

"Entwässern Entlütungsleitung bei Frostgefahr Tauchbunker 4 Stb bzw Bd"

Sheet 9 index item "f" I'm having a problem with "Frostgefahr"

Regards,
Don_

Don.
First question: Drain in case of freezing danger of dive bunkers 4 port and starboard via venting pipe. I guess you have misprinted the german word for ventingpipe which should read: Entluftungsleitung.
Frostgefahr: danger of freezing, "Freezing danger".

Tore

Don Prince · « **Reply #16 on:** 26 Aug , 2016, 12:44 »

Hello Mr. Tore,

I have been reading through the MAN 9 cylinder diesel engine USN document and after the schnorkel was installed on the U-Boat IXC they replaced the reversing cam with a cam that reduced the overlay of the valves. I don't see any reference in our discussions about the GW 6 cylinder diesel engine on the type VII. U-995 diesel control panel had the reversing lever removed and had the schnorkel installed. Did the make any changes to the cam timing on the GW engines? I have attached a link to what I was reading...

http://www.uboatarchive.net/Design/DesignStudiesTypeIXC-S41-5.htm

Regards,
Don_

tore · « **Reply #17 on:** 26 Aug , 2016, 13:47 »

Don.
As you know there is a significant difference in the GW and MAN engine, you may say, MAN was the Ferrari and GW the Ford. With regard to the timing of the exhaustcams MAN was more susceptible to back pressure variations as they were equipped with the BUCHI system, an early version of todays turbo supercharger systems. The Buchi system was, as to days turbocharger system, in continious operation over the whole power range. At that time the it was difficult to get the alloys for exhaustgas turbine blades capable of withstanding the high temperatures. The temperatures increases with the back pressure so I guess they had to install the special schnorchelling cams for continious schnorchelling in order to increase the overlapping to get the exhausttemperatures down. This in contradiction to the GW engine having a mechanical supercharger (Roots blower) which was only clutched in at high loads and revs. Thus on the GW engines the whole reversingmechanism including the reversing cylinder and astern cams were removed which simplyfies the engines and give a very welcome weight reduction particulary for the VIIC/41 type.
Tore

Don Prince · « **Reply #18 on:** 31 Aug , 2016, 22:05 »

Hello Mr. Tore,

I placed the file Skizzenbuch IX 11 x 17 - Prologue.pdf in the Skizzenbuch Type IX folder in dropbox. You have full permission in that folder, so you should be able to download or visw the file. This is very similar to the Type VII Prologue section with 20 pages (Mostly Graphics). Please review what I have done and I look forward to your expert comments...

Regards,
Don_

tore · « **Reply #19 on:** 31 Aug , 2016, 23:36 »

Don. For some reasons I can`t find the IX folder in the drop box, I only get the VIIC mailed 17 days ago. I am still at my remote farm with limited internet capacity but I am expected one of my grandsons up for the week end hopefully he might be able to figure out what`s wrong.
Tore

Don Prince · « **Reply #20 on:** 01 Sep , 2016, 18:47 »

Hello Mr. Tore,

I deleted the share and re-established it again... The file is below all those IXC images...

Regards,
Don_

Don Prince · « **Reply #21 on:** 02 Sep , 2016, 11:45 »

Hello Mr. Tore,

I corrected some of the drawings where I didn't have MBT 1, MBT 5, and MBT 8 flooded when summerged. I also corrected a spelling error. The new file Skizzenbuch IX 11 x 17 - 0 - Prologue.pdf is in the Skizzenbuch Type IX folder...

Regards,
Don_

tore · « **Reply #22 on:** 03 Sep , 2016, 04:58 »

Don I still don`t get the IXC Skizzenbook folder. Could you kindly share on my other E-mail adresse tberg-ni@online.no?
Tore

Don Prince · « **Reply #23 on:** 03 Sep , 2016, 13:21 »

Done....

tore · « **Reply #24 on:** 04 Sep , 2016, 00:15 »

Don.
Thanks, I got it and shall revert after reading your prologue.
Tore

Don Prince · « **Reply #25 on:** 04 Sep , 2016, 20:04 »

Hello Mr. Tore,

I really do apologize for wasting your valuable time... I read over the prologue again and I was astounded to see so many stupid mistakes. I have corrected some of the stuff that you have told me about before, and I sure hope I have it right this time.

Skizzenbuck IX 11 x 17 - 0 - Prologue.pdf was just uploaded...

Kind regards,
Don_

tore · « **Reply #26 on:** 05 Sep , 2016, 02:37 »

Don. A few comment to your prologue. May be it would be an idea to start with the pressure hull which on the IXc is divided into 5 pressureproof compartments as indicated on my image below. Each compartment is separated by a doomed pressureproof bulkhead and have a separate escape
( access)hatch. Further as the 9 cylinder main engines are having a considerable weight, you would like to avoid a large moment,distance from the submarines center of gravity and buoyancy, hence the main engines are placed next to the control room.
If you should like to stay to the RN English may be you should go back to hydroplanes instead of diveplanes.
Emergency mechanical operated steering. I am not sure if you used same for "silent running" we never did on the VIICs.
Mechanical connected hydroplanes. May be you misunderstood my remark on the porpoise effect of the independent hydroplane control. By purpoise effect ( a type of dolphin) we mean an alternating up and down movement of the submarine as a consquence of unexperienced hydroplane operators. The delicate interplay between the skilled forward and aft hydroplane operators, normally make an smooth controlled movement of the submarine, if you have unexperienced hydroplane operators they might create a porpoise effect which at periscope depth could cause you are breaking the surface.
Tore

Don Prince · « **Reply #27 on:** 05 Sep , 2016, 19:39 »

Hello Mr. Tore,

I will take your advice and change the Prologue to comply with your suggestions...

The info below is from the US Navy report on the Type IX C U-Boat.

STEERING AND DIVING

SUMMARY

The steering gear and plane operating gear operates on a traveling screw-fixed nut principle. Push button electric control is provided, and hand-wheels are fitted for emergency and silent-running service. Bow planes are permanently rigged out. Twin steering rudders are provided.

Rudders and planes are well located to obtain maximum effect with minimum area. The systems are compact, but are not otherwise unusual in any respects, and do not warrant exploitation.

Regards,
Don_

Don Prince · « **Reply #28 on:** 05 Sep , 2016, 23:48 »

Hello Mr, Tore,

Perhaps the 3rd time is a charm... I believe I have got the Prologue right (or very close to being right). I will always concede to your wisdom about U-Boats. I have uploaded my latest Prologue into the dropbox Type IX folder...

Regards,
Don_

tore · « **Reply #29 on:** 06 Sep , 2016, 00:34 »

Don. Shall recheck your last prologue today. Your remark on manually operated hydroplanes during silent running. You are right, the German instruction in the Handbook for submarine commanders says you should switch over to manual operation of the hydroplanes during silent running see copy below. As I said we never followed the German instructions.
Tore

tore · « **Reply #30 on:** 10 Sep , 2016, 02:11 »

Don. I have read your IXC prologue and have a few remarks.
Page XII I guess it would be appropriate to describe the attack periscope only to be used in the tower as fully hydraulic operated both raising and lowering as well as rotating, allowing the CO to sit for accurate observation. At the time of the WW2 this was a unique design.May be an image of the attack periscope would be helpful.
Page XV When showing the floodvalves, I guess if you stick to the RN English you may use Kingstons for the flood valves.
Page XIX You normally fill the regulating tanks to the COs order to fulfill his request as to the buoyancy at the required depth. For inst. some times he would like it a bit heavy at periscope depth when you have a rough swell to make it a bit better for the hydroplane operators to holde the submarine at periscope depth.
Page XX you are able to use hp air at 25 atu blowing the Qs, this does not mean you are using full pressure all the time, it all depend on circumstances and you always keep an eye on the air consumption.
Page XXI Overpressure inside the pressure hull is the result of many cases like inside venting and leakages from a number of valve connections. The overpressure upset all the manometers as well as the boiling temperatures and as such a nuisance.
Sorry for the late answer as my internetconnection is too slow, I hope to get it better next month.
Tore

Bob Tomlin · « **Reply #31 on:** 20 Sep , 2016, 06:12 »

Hello Mr Tore, Don,

Many apologies as I feel as though I'm interrupting two very knowledgeable gentlemen in mid conversation here, but I did wonder if this might be the best place for a layman such as myself to perhaps get an answer to a technical question on a Type IXC/40 please?

I'm modelling a IXC/40 (U-889) at the moment and I'd like to ask about the rectangular diesel outlet on the sides of the hull please.
This is quite a large aperture on the model and so I wanted to put some sort of construction in the space behind it to represent something of what should be there (the visible bit anyway).
I was thinking initially that this would be a sort of rectangular box type duct?

I've been reading that passage regarding the exhaust that mentions mufflers, water jacketing, spark arrestor chamber, valves, etc. but can't find any plans or good photos for me to make some sense of it all.
I've seen some shots taken looking down on the salvaged U-534 which show some structure as viewed from above, but this doesn't tell me what's happening on the undersides.
I came across this piece of film of the U-889 which shows water draining from the twin drainage holes below the exhaust outlet (particularly at the 00.40 point into the film), but not much draining out of the actual exhaust outlet itself. I then wondered whether or not there might be a drainage channel which would be in the 'floor' of any 'box type exhaust ducting' in order to either allow for maximising drainage from there?
http://footage.framepool.com/en/shot/678512935-corvette-ship-royal-canadian-navy-surrendering-naval-warfare

A lot of the structure has disintegrated on the U-534, (which I've been examining lately), the only small bits of structure that are left in the aperture being two small 'ribs' at one third intervals on the top edge of the aperture.
I've attached a very rough sketch to indicate the area I'm talking about (as I'm very likely using all the incorrect terms for parts). It's only representational and rough of course, so nothing's to exact scale.

Any help on what might be in there or suggestions on where I could find the answers would be very much appreciated please. Thank you.
I'm going down to the national archives at kew in a couple of weeks so could pull out a file if you happen to know if the information might be in one.

SnakeDoc · « **Reply #32 on:** 20 Sep , 2016, 11:31 »

Hi Gentlemen,

welcome back after two month, it is good to see so many new posts and discussions.

Quote from: tore on 18 Aug , 2016, 03:09

Quote from: Don Prince on 17 Aug , 2016, 20:50
I got some interesting photos of U-505... I am curious about the Dive Plane control stations; it looks like the two manual control wheels are tied together by a sprocket and chain. Would that mean that if there was a power failure, then both dive planes would move in the same direction (sort of parallel to each other)? what do you thing?

It looks indeed as the two manual hydroplane controlwheels are interconnected by chaindrive, I never saw it before. I assume the electrical push button system is unaltered and thus the dual operated system is an emergency system. Generally the forward hydroplanes are used for depthcontrol (pitch) and the aft hydroplanes for leveling, on the VIICs. This system required two operators. todays submarines combines the two, thus reducing the manning.
I am astonish to see that the IXCs emergency system of the 1940 years already got a rude version of it. The flexibility of the two man operation is gone however, but I assume a possible porpoising effect as well, interesting.

Regarding the above quote, I recommend the following fragment of the type IXC study:

Quote

It is of interest here to note that later vessels if the type have a third plane control station in the control room and a manual coupling and chain connection between the bow and stern plane handwheels. These are provided to permit the following type of operation:

If there is a casualty to the electric control of either the bow or stern planes, the two hand wheels can be tied together so that two men can simultaneously control the affected planes in hand. The diving officer connects the third pair of planes and operates them electrically.

--
Regards
Maciek

tore · « **Reply #33 on:** 20 Sep , 2016, 13:08 »

Maciek.
Welcolme back, we missed you. Hope everything is OK and am looking forward to your participation in the discussion especially on the IXC which I have no experience.
Tore

tore · « **Reply #34 on:** 21 Sep , 2016, 13:29 »

Bob.
I guess you have a pretty good idea about the spark arrestor arrangement having done some research on your own hand. I am not so conversant with the IXC but I guess the IXC followed pretty much the development of the VIIC. Which has a number of alternative solutions to the exhaust outlet. The arrangement is a dry silencer having a coolingwater jacket with an outlet to the compensating tank in the tower and from this tank overboard. The spark arrestor being the last item in the system was in the beginning a wet type meaning the exhaust gases were led down under the seawater before the outlet. I don`t think it was any connecting pipe to the water jacket on the silencer, thus somehow baffle plates led the exhaust down below the sea surface and then via the water up through the slit in the casing. The two floodgates below was probably at the top level of the water in the spark arrestor hence only occasionally draining water as the water level changed. Later the system was changed and the sparkarrestor was removed and the exhaustpipe ended under the sealevel. Again this is the VIIC development but I assume the same development took place with the IXC as well. May be my image below can be of some help.

Tore

Bob Tomlin · « **Reply #35 on:** 21 Sep , 2016, 15:15 »

Hello Mr Tore,

Thank you very much for that information. I'd read about the spark arrestor in that study document from the Canadian Navy but I wasn't sure how it worked.
It mentions keeping a water trap at the same level. Am I right in thinking this principle to be a similar sort of thing to a toilet 'U-bend' then, with the exhaust gases having to pass through this water?
As I mentioned I'm going down to the National Archives to have a look through some files (one is titled:- 'U-boats: Diesel engines') so they may give more answers if they go into exhausts.

A lot of the current U-534 internals have corroded away, unfortunately and the port diesel exhaust has been plated over (the starboard one isn't accessible for close inspection) but I had a look in to see what clues there might have been to this construction and I took this shot. It might be my eyes of course but there appears to me to be a 'curving plate' which looks as though it might meet the position of the lower edge of the exhaust aperture. It might well be some other structure that has simply fallen down due to corrosion, but I did wonder if this could be part of the construction that constitutes the spark arrestor chamber (i.e. a descending baffle leading down to this water level)? ...or not.

Thank you again,
Bob.

Don Prince · « **Reply #36 on:** 21 Sep , 2016, 16:25 »

Hi Maciek,

Good to see you again my friend... What does it mean "The diving officer connects a third set of planes and operates them electrically."

A third set of planes - or - a third set of BBC controllers (1 or 2)? What and where is this located... I believe the dual rudder has a BBC controller in the control room, the tower, and a manual hand wheel in the aft torpedo room.

Regards,
Don_

Don Prince · « **Reply #37 on:** 22 Sep , 2016, 00:06 »

Hi Maciek,

I have been attempting to understand the relationship between the bow buoyancy tank and MBT 1... This is what I came up with looking at the 1 dimensional drawings. This is my 3-Dimensional view; what do you think?

Regards,
Don_

tore · « **Reply #38 on:** 22 Sep , 2016, 01:15 »

Don.
Interesting and useful!
Tore

SnakeDoc · « **Reply #39 on:** 22 Sep , 2016, 12:18 »

Hi Don,

Quote from: Don Prince on 21 Sep , 2016, 16:25

What does it mean "The diving officer connects a third set of planes and operates them electrically."

A third set of planes - or - a third set of BBC controllers (1 or 2)? What and where is this located... I believe the dual rudder has a BBC controller in the control room, the tower, and a manual hand wheel in the aft torpedo room.

take a look at the "Schaltbild der Tiefenruderanlage" in the Skizzenbuch fur das Machinenpersonal IXC (Band E Allgemeine E Anlagen).

You can see there two standard electrical BBC controllers (for forward and aft diving planes), and between them, the third, dual BBC controller, which could be connected (by means of the integrated change-over switch) either to forward or to aft diving planes driving motor.

I could not locate this third controller on any available photo of the type IXC control room. From the wiring diagram, it seems that it was fixed connected (not by means of the socket and plug), and as so, it should be somehow attached to the other equipment or hull.

Diving planes controllers (electrical and mechanical) were located in the control room only (as in control room only were located the respective instruments: inclinometers, Papenberg depth-meters, depth-gauges).

Regarding the main rudder, the standard helmsman station was in the conning tower, where the BBC controller was located. This controller was detachable and connected by means of the flexible wire and plug and socket. After detaching, it could be moved to the bridge, and during the harbor maneuvers, the boat could be steered from there.

The second (backup) control station was located in the control room, where the fixed BBC controller was located (at the forward bulkhead of the control room). It was intended to use, when the conning tower was damaged (i.e. flooded). In the later period of war, on the Schnorchel boats, it was used as a primary control station.

Some time ago, Tore described the reasons of the change, and his experiences regarding that arrangement. If remember correctly, it was related with the better communication between all three men controlling the planes (that is main rudder, and two sets of diving planes), which was especially important during Schnorcheling.

The emergency, manual control station was in the aft torpedo room.

--
Regards
Maciek

SnakeDoc · « **Reply #40 on:** 22 Sep , 2016, 12:36 »

Hi Don,

Quote from: Don Prince on 22 Sep , 2016, 00:06

I have been attempting to understand the relationship between the bow buoyancy tank and MBT 1... This is what I came up with looking at the 1 dimensional drawings. This is my 3-Dimensional view; what do you think?

I'm not sure about this top part protruding from the ballast tank (btw. I believe you meant MBT 8 ). I think, that in this area were located anchor windlass with its driving gear and capstan gear. I think, that all space at the level of the bow buoyancy tank, further aft, was just free-flooding space under upper-deck.

--
Regards
Maciek

Don Prince · « **Reply #41 on:** 22 Sep , 2016, 17:19 »

Hi Maciek,

You know - I should NOT attempt to multitask when doing drawings... The label for the buoyancy tank was WRONG!!! Here is the corrected version and the print I got it from.

Regards,
Don_

SnakeDoc · « **Reply #42 on:** 23 Sep , 2016, 01:22 »

Hi Don,

Quote from: SnakeDoc on 22 Sep , 2016, 12:18

I could not locate this third controller on any available photo of the type IXC control room. From the wiring diagram, it seems that it was fixed connected (not by means of the socket and plug), and as so, it should be somehow attached to the other equipment or hull.

At the beginning of the type IXC Design Study you can see the photo:

On two upper photos, near the antenna shaft, there is visible something like electrical controller, I guess, it is third diving planes controller we were looking for.

--
Regards
Maciek

tore · « **Reply #43 on:** 23 Sep , 2016, 01:46 »

Maciek.
Absolutely, I never saw it before, we did not have this arrangement on the VIIC . In fact the construction reminds me of the of the hydraulic ( oleosystem) actuators for the hydroplanes of RN submarines.
Tore

SnakeDoc · « **Reply #44 on:** 23 Sep , 2016, 01:57 »

Hi Don,

Quote from: Don Prince on 22 Sep , 2016, 17:19

You know - I should NOT attempt to multitask when doing drawings... The label for the buoyancy tank was WRONG!!! Here is the corrected version and the print I got it from.

I think it looks OK.

--
Regards
Maciek

Don Prince · « **Reply #45 on:** 23 Sep , 2016, 12:33 »

Hi Maciek,

Could this be it?

Regards,
Don_

SnakeDoc · « **Reply #46 on:** 23 Sep , 2016, 14:52 »

Hi Don,

Quote from: Don Prince on 23 Sep , 2016, 12:33

Could this be it?

I don't think so. From the wiring diagram it seems, that switch (fwd/aft/off) is integrated with controller (not as separate box).

On the photo from the design study there is visible controller with one large, horizontal handle and smaller switch below. I guess that this selection switch is 3 position switch (vorn/acht/aus).

I have attached the photo, where I marked the switch. The photo is low-resolution, but one can see some details of the controller.

I doubt, if we can find the controller on the present photos from U 505 control room. Some equipment was removed for investigation in corresponding labs, some was removed when converting to museum and so on.

Regarding the box you have marked on your photo, I think that it is distribution box (maybe for Ordering and Reporting installation - BuM Anlage). I have found other view of this box. Please compare with the similar the box in the U 995 control room (see attachments).

--
Regards
Maciek

Don Prince · « **Reply #47 on:** 23 Sep , 2016, 22:45 »

Hi Maciek,

Yep! I believe you are correct about the selectable 3rd hydroplane controller unit location. This controller allows them to switch-out a defective BBC hydroplane unit (fwd or aft). However, they could have simply went manual on one BBC control unit and the other BBC unit could continue to run electrically; they wouldn't be tied together by chain drive unless both units were switched to manual.

It looks like the whole purpose of the 3rd control unit was they did not want to go to manual control of a hydroplane! Why?

The electrical drawing for the rudder BBC control unit indicates the tower rudder BBC unit was just unlatched and taken to the bridge with the cable running through the tower hatch. I don't believe they would want to water proof a receptacle for the controller on the bridge. Also, there is a cut-off switch to disable the tower BBC rudder unit in the control room. I suppose they would disable the tower BBC unit if the helmsman was in the control room, or the tower got flooded. Let me know if you find the cut-off switch...

Regards,
Don_

SnakeDoc · « **Reply #48 on:** 24 Sep , 2016, 02:30 »

Hi Don,

Quote from: Don Prince on 23 Sep , 2016, 22:45

Yep! I believe you are correct about the selectable 3rd hydroplane controller unit location. This controller allows them to switch-out a defective BBC hydroplane unit (fwd or aft). However, they could have simply went manual on one BBC control unit and the other BBC unit could continue to run electrically; they wouldn't be tied together by chain drive unless both units were switched to manual.

It looks like the whole purpose of the 3rd control unit was they did not want to go to manual control of a hydroplane! Why?

Well, in my opinion, the scenario is as follows: the electric drive for the aft/fwd diving planes fails (electric motor, power or control). So this (aft/fwd) diving planes needs to be controlled manually. The electric motor is decoupled pneumatically, and the driving shaft is connected. The driving shaft is driven by respective handwheel.

Now, I suppose, due to length of the shaft (25-30 meters) and many couplings and joints between the handwheel and diving planes gear, the designers anticipated difficulties in movement the shaft by one operator. So they provided the gear for coupling both handwheels together, so both operators could use their strength to drive resistive shaft.

But if both operators were controlling one diving planes, the other one has to be controlled by another man. Assuming, that this other diving planes set was not-damaged (could be controlled electrically), this was done by means of the third controller by another crew member.

Quote from: Don Prince on 23 Sep , 2016, 22:45

The electrical drawing for the rudder BBC control unit indicates the tower rudder BBC unit was just unlatched and taken to the bridge with the cable running through the tower hatch. I don't believe they would want to water proof a receptacle for the controller on the bridge. Also, there is a cut-off switch to disable the tower BBC rudder unit in the control room. I suppose they would disable the tower BBC unit if the helmsman was in the control room, or the tower got flooded. Let me know if you find the cut-off switch...

I cannot locate this switch on the U 505 photos. I suppose, it's missing. In U 995's control room this switch (labeled as Seitenruder) is near the rudder controller in the control room (see attachment).

--
Regards
Maciek

Don Prince · « **Reply #49 on:** 24 Sep , 2016, 23:01 »

Hello Mr. Tore and Maciek,

The photo attached shows the bow of U-505 and the flooding slots and the flood gates near the torpedo chute. You can see internal flooding slots for the bow buoyancy tank through those huge flooding slots on the torpedo chute. The drawing attached shows the bow buoyancy tank layout where there is a fairly large space below the bow buoyancy tank. My prints refer to the area that includes the space above and below the torpedo tubes as "Durchfluteter Raum" or Flooded Room. Could the space above the upper flood gates just be considered as part of the bow buoyancy tank? There doesn't look to be any means to vent that upper area?

Regards,
Don_

tore · « **Reply #50 on:** 25 Sep , 2016, 07:26 »

Don.
Based on the GA plans of VIICs I guess the IXCs bow buoyancy tank might be something as my image below, the floodgates would probably be the first line of gates from the bowdeck .
Tore

SnakeDoc · « **Reply #51 on:** 25 Sep , 2016, 11:47 »

Hi Don,

on the attached drawing, the buoyancy tank is marked with green color, and I believe, that volume (given in technical data) 11,89 m³ and 12,89 m³ (at type IXC and IXC/40 respectively) refers to this green area.

However, as you noted, the upper part of the free-flooding volume (marked with grey color) also can be considered as part of buoyancy tank, because when you are blowing buoyancy tank, the joint volumes green and grey are blown.

So I think, that strictly speaking, the buoyancy tank is only the green part, but some space below (grey) can be considered as a part of it as a side effect of flooding slits located just above torpedo tubes.

One can ask, why designers did not locate these flooding slits higher, just below the buoyancy tank (i.e. between grey and green areas)? I almost sure, that it's because of the large flooding gates inside the torpedo tube recess. These large flooding gates are intended to catch any air bubbles, that can escape from the torpedo tube during the torpedo launch. These air bubbles would float toward the top of the buoyancy tank and there be stored, instead of floating to surface and betray the boat position.
Such design was developed later into Schwallfang, used on type XXIII U-Boats.

Any other flooding slots between these "catching holes" and the bottom of buoyancy tank would corrupt this design.

--
Regards
Maciek

tore · « **Reply #52 on:** 26 Sep , 2016, 02:11 »

Maciek.
I guess the grey area may be considered as the variable buoyancy part of the tank which fluctuate as the boat pitches on the surface compressing the green area as the effective constant bow buoyancy. I have not been able to locate the bow buoyancy vent and operation arrangement, do you have any details Don?
Tore

Don Prince · « **Reply #53 on:** 27 Sep , 2016, 18:05 »

Hello Mr. Tore,

I'm still looking for drawings similar to the Type VIIC diagrams with all the valves. The only thing I have is the photo of U-505 and I point to the metal grate above the vent valve for MBT 8 (Bow Main ballast Tank).

Regards,
Don_

tore · « **Reply #54 on:** 27 Sep , 2016, 23:11 »

Don.
I don`t think the bow buoyancy vent could be operated mechanically from the controlroom it was probably operated locally as on the older type IIVCs or even pneumatically.
Tore

SnakeDoc · « **Reply #55 on:** 28 Sep , 2016, 07:59 »

Hi Tore, Don,

Quote from: tore on 27 Sep , 2016, 23:11

I don`t think the bow buoyancy vent could be operated mechanically from the controlroom it was probably operated locally as on the older type IIVCs or even pneumatically.

according to type IXC Design Study, bow and stern buoyancy tanks have vents operated manually from the bow and aft torpedo room respectively.

--
Regards
Maciek

SnakeDoc · « **Reply #56 on:** 28 Sep , 2016, 10:35 »

Hi Don,

Quote from: Don Prince on 27 Sep , 2016, 18:05

I'm still looking for drawings similar to the Type VIIC diagrams with all the valves. The only thing I have is the photo of U-505 and I point to the metal grate above the vent valve for MBT 8 (Bow Main ballast Tank).

I believe, you marked the metal grate above the vent valve of the buoyancy tank. To the right the man-hole for access to the buoyancy tank is visible.

I believe, that the vent valve for the MBT 8 is located under wooden deck, further aft.

--
Regards
Maciek

Don Prince · « **Reply #57 on:** 28 Sep , 2016, 10:41 »

Hello Mr. Tore and Maciek,

Yes, I agree the vent valve for MBT 8 is under the wooden deck. Also. none of the main ballast tank vent valve hand wheels are located in the control room. It was much different in the type VIIC U-Boats. See the attached drawing...

Regards,
Don_

SnakeDoc · « **Reply #58 on:** 28 Sep , 2016, 10:53 »

One more thing regarding the third diving plane controller: while looking photos of the vent valves, I have found the photo of U534 control room (after salvage). You can see there a rusted BBC controller, the same as in U889 control room.

Regards
Maciek

Don Prince · « **Reply #59 on:** 08 Oct , 2016, 00:40 »

Hello Mr. Tore and Maciek,

The Type IX C/40 print on Plan 10 refers to an MBT blowing and emergency blowing system… I sure don’t see any emergency blowing system on that schematic? At least not to the hardware extent that was available on the early Type VII U-Boats. They can’t blow the Fuel 1a and Fuel 2a bunkers because there are no Kingston flood valves; they could only blow MBT 1, MBT 5, and MBT 8 which are the normal ballast tanks. However, if they are in a dyre position, they could open the Kingstons and blow the RFO tanks; MBT 3, MBT 4, MBT 6, and MBT 7…

Would that be the emergency blowing system?

On her second war patrol starting on 1.12.42 U-175, a type IX C U-Boat, encountered a heavy air attack which resulted in extensive damage. The U-boat sank stern first to a depth of 310 meters (1,017 feet), which was well beyond the hull's tested crush depth. The emergency release of the ballast reversed the plunge into the deep and saved U-175 to fight another day. On her third and last war patrol starting on 10.4.43, U-175 encountered two depth charge attacks by the US Coast Guard cutter Spencer. U-175 surfaced heavily damaged and 12 crewmen were lost and 41 became PoW.

Regards,
Don_

SnakeDoc · « **Reply #60 on:** 08 Oct , 2016, 04:55 »

Hi Don,

Quote from: Don Prince on 08 Oct , 2016, 00:40

The Type IX C/40 print on Plan 10 refers to an MBT blowing and emergency blowing system… I sure don’t see any emergency blowing system on that schematic? At least not to the hardware extent that was available on the early Type VII U-Boats. They can’t blow the Fuel 1a and Fuel 2a bunkers because there are no Kingston flood valves; they could only blow MBT 1, MBT 5, and MBT 8 which are the normal ballast tanks. However, if they are in a dyre position, they could open the Kingstons and blow the RFO tanks; MBT 3, MBT 4, MBT 6, and MBT 7…

Would that be the emergency blowing system?

On the plate 10 is no sign of the emergency blowing system. I guess, the drawing was modified (the salvage system was removed), but title not. I think it is normal, that in the late-war more and more inconsistencies appeared.

From the Design Study:

Quote

14. Salvage air arrangements, while shown in sketch books and text material were not actually installed in surrendered vessels.

Quote from: Don Prince on 08 Oct , 2016, 00:40

On her second war patrol starting on 1.12.42 U-175, a type IX C U-Boat, encountered a heavy air attack which resulted in extensive damage. The U-boat sank stern first to a depth of 310 meters (1,017 feet), which was well beyond the hull's tested crush depth. The emergency release of the ballast reversed the plunge into the deep and saved U-175 to fight another day. On her third and last war patrol starting on 10.4.43, U-175 encountered two depth charge attacks by the US Coast Guard cutter Spencer. U-175 surfaced heavily damaged and 12 crewmen were lost and 41 became PoW.

"The emergency release of the ballast" - it means the emergency blow, i.e. procedure of blowing ballast (with normal blowing system) at depth. As you know, normally blowing at depth was avoided, because it used a lot of compressed air. First it was desired to decrease depth dynamically (using speed and hydroplanes), and finally blow ballasts near the surface (this required less amount of air than blowing at depth).
That's why blowing at depth was called emergency blow.

"The emergency release of the ballast" was not related with the emergency blowing system ("Notausblasenanlage"). "Notausblasenanlage" was rather salvage system, which made possible to blow the ballasts (from the outside - by divers) of the sunken boat. Because it was usable only in the areas, where boat can not sunk very deep (practically < 100 m, below the divers cannot descent, I guess Tore will explain this further), it was installed only on new boats that were directed to the training in Baltic sea, and on training units. Because during training many accidents could occur, the salvage (emergency blowing) system could make possible to salvage the boat and rescue the crew. After the boat passed the training and was combat-ready, the salvage system was removed.

--
Regards
Maciek

tore · « **Reply #61 on:** 08 Oct , 2016, 05:39 »

Don. I fully agree with Maciek. The wording emergency release of ballast might be an old expression deviating from a system of the WW1 submarines where the boats very often carried a mechanical fixed ballast attached to the keel, this ballast could in some cases consisted of lead. In emergency you could release the ballast from the controlroom and surface the boat. However when depthchargers were introduced, the ballast had occasionaly a tendency to be released by the depthcharge attack and the system was abandoned on the WW2 uboats. As in many naval expression may be some people still used the old expression "drop the ballast".
Tore

Don Prince · « **Reply #62 on:** 08 Oct , 2016, 23:51 »

Hello Mr. Tore and Maciek,

I have a problem with Plan 9, the text sheet says there is an item (g) a grease fitting, but I can not find one on the print? Any thoughts? Also the drawing for the bow and aft buoyancy tanks has the drain valves item (f) outside of the pressure hull. I don't believe that is correct... What do you all think?

Regards,
Don_

Don Prince · « **Reply #63 on:** 09 Oct , 2016, 00:02 »

Hello Mr. Tore and Maciek,

I have a translation problem, or things just don't match up with the text sheet and Plan 11. I'm having problems with the German text for items (c) and (d). Item (c) looks like an external gate valve to me, and Item (d) looks like an internal emergency blowing cock or hand wheel. All assistance is appreciated...

also Plan 11 calls out the ballast tanks for a IX C and the drawing is for a IX C/40 U-Boat... That part I can handle.

Regards,
Don_

tore · « **Reply #64 on:** 09 Oct , 2016, 01:53 »

Don
I guess the system is quite similar to the VIICs. The Cs are the external gatevalves for isolating the external reserve bunkertanks when in fuel mode. The ds are the emeregency shut off valves operated from inside for the external vent ducts of the ballasttanks. The possible reason for a confusion is that plan 9 has exchanged c and d.
Tore

Don Prince · « **Reply #65 on:** 10 Oct , 2016, 11:12 »

Hello Mr. Tore and Maciek,

I believe the Items I marked should be within the pressure hull and not in the aft buoyancy tank or within MBT 8 as drawn in the original German diagrams. This German version of this Skizzenbuch has the title cover for the IX C/40 U-Boat, but many of the diagram Text sheets reference the IX C U-Boat (MBT 2). Apparently, the control for the shipbuilding documentation was in disarray as early as August of 1943. See my attached drawing...

Regards,
Don_

tore · « **Reply #66 on:** 12 Oct , 2016, 06:13 »

Don.
I am not sure I have full understanding of your question. The way I see it is the image shows the mechanical operation of the vents of fore and aft buoyancy tanks which are outside the pressurehull having an arrangement of mechanical operation by a wheel inside the pressurehull. The cocks f are on the greaselines to the arrangements.
Tore

Don Prince · « **Reply #67 on:** 13 Oct , 2016, 14:49 »

Then this is what is confusing to me...

Item (f) is listed as "Entwässern Entlüftungsleitung bei Frostgenfahr Taunchbunker 4 Stb bzw Bd."
Item (g) is listed as "Fetten - - - zB Flutklappe Tauchbunker 2 Stb."

In order to pump grease into the bow and aft lines, then the line and valve must be inside the pressure hull and not outside as drawn. It looks like the descriptions were transposed again, and I don't see any item (g) on the print (Previous drawing uploaded)?

Regards,
Don_

tore · « **Reply #68 on:** 14 Oct , 2016, 01:32 »

Don
I don`t think it is full correlation between your German text and plan 9 it could possibly refer to another plan.
Tore

Don Prince · « **Reply #69 on:** 14 Oct , 2016, 12:38 »

Hello Mr. Tore,

I absolutely agree, the German Text does not match Plan 9's drawing in the book... Early on, I recognized that the Skizzenbuch was for the type IX C/40 U-Boat, but some of the text pages still referenced the type IX C U-Boat physical characteristics. The German Skizzenbuch copy that I have looks to be a transition book from the Bundesarchiv. Therefore, I had to cover both U-Boat types in order use the text sheets and the drawings. Basically, the only difference between the type IX C and the type IX C/40 is the IX C is more complicated because of the presence of MBT 2 and all the hardware required for the ballast tank and the RFO option. Physically, the IX C/40's U-Boat's beam is 0.1 meters wider than the type IX C U-boat. That's it!

I have discussed this with Maciek and I have drawn a modified Plan 9 and produced a Type IX C drawing which seems to match the original text page that I uploaded. The only question that remains unresolved for me is item (f) the "Drainage Vent Pipe for Freezing Danger MBT 4 Port and Starboard" and item (g) "Grease Fitting - - - For Example: Kingston Flood Valve MBT 2." There is NO item (g) in the drawing, so are the 4 lines from all the Kingston flood valves a drainage line or a grease fitting?

I have attached my drawing of the Plan 9 for the type IX C U-boat.

Regards,
Don_

tore · « **Reply #70 on:** 14 Oct , 2016, 14:37 »

Don.
I cannot see any use for drain on the Kingstons and certainly not for danger of frost. So I guess the "f" for the Kingstons would be shut off cocks for the grease lines. I Guess the only need for venting and waterdrainage in case of frost would be the venting pipesystem with gatevalves and emergency flapvalves below the casingdeck. The "e" is clearly marked as a drain in the system. However it is strange to name "f" cocks both as drain and grease cocks, hence it might be another systemsketch they are refering to where the "g" cocks are shown as well.
Tore

Don Prince · « **Reply #71 on:** 21 Oct , 2016, 00:18 »

Hello Mr. Tore and Maciek,

I have suspended work on the Type IX Skizzenbuch until I get through the clean-up on the Type VII C Skizzenbuch. I should have the cleaned-up version in dropbox in about 2 weeks. However, If you all have any suggestions, then please let me know...

Maciek, about my Internet provider Comcast rejecting your email. I called and talked with then 2 days ago and they were supposed to fix the problem. I haven't had any issues with emails from Jak Showell in the UK. I think it may have to do with your email address "Snakedoc", I can see them thinking this is spam!!! Can you try and email me again and let's see if they resolved the issue...

Regards,
Don_

tore · « **Reply #72 on:** 21 Oct , 2016, 00:30 »

Don.
As to Macieks problem with US rejection of E-mails. I experienced the same as mine ended up in the US spambin in some of the states. I changed my E-mail address and everything is now OK.
Tore

Bob Tomlin · « **Reply #73 on:** 01 Jan , 2017, 05:01 »

Happy New Year Tore,

I know you said last time I had a question that you had more experience of type VIIs than IXs, but I thought I'd try here with this question if that's ok as i'm not having much success finding out about these anywhere else yet.
Here's a sketch of two things that I can see on type IXC/40 U-889 in period photos.

The top 'thing' is something I see on type IXs quite a bit in photos. They are usually found over the deck 'flap-type' hatches sometimes immediately forward of the magnetic compass housing
or sometimes on the hatches midway betweeen the tower and bow on the foredeck. There's often a longer version of these over the hatches at the stern end of the boat too.
All I can make out in photos are the sketchy sort of details that I've drawn above and that might be enough for 72nd scale, but I did wonder if you might have ever come across these or something like them and knew what they are or how they work/attach?

The bottom 'thing' is something that I've seen in photos on some Type IXs (including the U-889) which looks to me like a sort of bar/rod that 'locks' over part of this type of hatch.
I've seen this type of hatch on some type VIIs as well, so wondered if you might have come across anything like this and knew again what it is and how it works? Not all hatches of this type seem to have this 'bar' across them so I wondered if it might be a modification/later introduction or something?

Thanks very much for any help.
Bob.

tore · « **Reply #74 on:** 30 Jan , 2017, 08:46 »

Bob.
As you probably have noticed my PC crashed and I have not been able to communicate for the last 3 weeks which I regret. The marker buoy hatch is a leftover from the earlier VIIC design which contained two markerbuoys able to be released from inside the submarine for emergencies. They were removed sometime in 1942 but several VIICs delivered after that time had the marker buoycontainers installed without buoys. Even good old U 995 had the forward container(not the aft), although due to the Schnorchel it was replaced from off center ( port) at appr. frame 60 to in front of the Ascaniacasing (on U 995 the old type). On the image below you see me almost standing on the hatch.
The "bar" you are refering to is unknown to me and seems to be a quick temporarely securing to prevent the hatch to be flung open in case of depthcharging.

Bob Tomlin · « **Reply #75 on:** 13 Feb , 2017, 05:22 »

Thanks very much for that, Tore.
I hadn't noticed that you'd replied until today.
Great photo.

Cheers Bob.