Author Topic: Atlantic Bow modified for underwater refuelling (Read 11295 times)

NZSnowman · « **on:** 28 Dec , 2011, 12:28 »

Here is my research for the modified Atlantic Bow for underwater refuelling.

I welcome any feedback or discussion about it.

Would like to ask the other forum members if they have time to look through their U-boat photographs collection and see if they have any pictures of this bow alteration.

http://www.mediafire.com/?ms0cu75b786royo (You will need version 8 or higher to view the PDF file)

Nevermind4712 · « **Reply #1 on:** 28 Dec , 2011, 14:04 »

Thanks for your awesome Work Snowman:)

Is it okay for you that i divide the PDF with other german modelers?.
There are some really hot about this Information:)

NZSnowman · « **Reply #2 on:** 28 Dec , 2011, 14:32 »

Quote from: Nevermind4712 on 28 Dec , 2011, 14:04

Thanks for your awesome Work Snowman:)

Is it okay for you that i divide the PDF with other german modelers?.
There are some really hot about this Information:)

Thanks for the kinds words.

I have just uploaded a newer version of the PDF file as I found some spelling and grammar errors. (Sorry my spelling and grammar is real bad). This is only part of a larger PDF of all my research. I am current reworking all my Schnorchel research. Should have it finsh soon.

You are most welcome to forward it to other modellers!

SnakeDoc · « **Reply #3 on:** 28 Dec , 2011, 15:27 »

Great work, Simon!

You have touched really interesting and almost unknown topic.

--
Regards
Maciek

NZSnowman · « **Reply #4 on:** 28 Dec , 2011, 19:28 »

Quote from: SnakeDoc on 28 Dec , 2011, 15:27

Great work, Simon!

You have touched really interesting and almost unknown topic.

--
Regards
Maciek

Thanks Maciek

I had noted a while ago that there was two different Atlantic Bow versions, but did not know why. When the other day I was reading about loss U-boats in the English Channel and the talked about one of the U-boat being modified for underwater refuelling, and it all started to come together

Also a small update on the PDF file, fixed more spelling & grammar, and added one more drawing.

dougie47 · « **Reply #5 on:** 29 Dec , 2011, 13:47 »

Hi Simon,

Fantastic work! I don't think I've heard anyone discuss this subject before and your article really does provide very good information. It has been speculated that there were two Atlantic bow versions, one wider than the other. Do you think they are as follows? -

Version 1 - Normal Atlantic bow
Version 2 - Wider Atlantic bow due to addition of underwater refuelling

Might this explain the two versions?

We would be happy to add your article to the AMP library (under Documents / U-boats), under your name of course.

Cheers,

Dougie

TopherVIIC · « **Reply #6 on:** 29 Dec , 2011, 16:04 »

Good Stuff Simon! As usual, you have done a fine job!
Thanks!

NZSnowman · « **Reply #7 on:** 30 Dec , 2011, 12:40 »

Hi All

Just a small update on this research. Jerry Mason from Uboatarchive.net http://uboatarchive.net/ has ckecked the KTB for U-460 on the 7 December, and are no record of the underwater refueling for this day

So the date and/or U-boat numbers could be wrong.

Jerry, said he will translate the full KTB for U-460 in a few months, & I will check my notes again. So I will keep you posted of that we found.

NZSnowman · « **Reply #8 on:** 01 Jan , 2012, 01:09 »

Quote from: dougie47 on 29 Dec , 2011, 13:47

Hi Simon,

Fantastic work! I don't think I've heard anyone discuss this subject before and your article really does provide very good information. It has been speculated that there were two Atlantic bow versions, one wider than the other. Do you think they are as follows? -

Version 1 - Normal Atlantic bow
Version 2 - Wider Atlantic bow due to addition of underwater refuelling

Might this explain the two versions?

We would be happy to add your article to the AMP library (under Documents / U-boats), under your name of course.

Cheers,

Dougie

Hi Dougie

Thanks for the kind words.

My feeling is both Atlantic bows have the same measurements. I not seen any different that I can tell yet.

Dougie, thanks for the offer to add my article to the AMP library. I would like that

I have been updating my Schnorchel research also, and would like to combine most of my research into a single document. So, would is be Ok to do this, or would you prefer single research articles?

dougie47 · « **Reply #9 on:** 01 Jan , 2012, 13:06 »

Hi Simon,

Thanks for the reply, I'll send you an email.

Cheers,

Dougie

PS Happy New Year to everyone.

NZSnowman · « **Reply #10 on:** 02 Jan , 2012, 21:55 »

I have just finish another small update for this article.

I have added additional information on the Telephone Cable, Fuel Hose, added detail of U-460 War Diary/War Log Book (KTB), corrected the Fuel Hose and fuel valve alignments and dimensions, and added a new drawing to illustrate arrangement for the fuel hose.

Happy viewing

http://www.mediafire.com/?ms0cu75b786royo

TopherVIIC · « **Reply #11 on:** 03 Jan , 2012, 08:57 »

Simon -
Nice drawings and report, as always. I look forward to seeing the final piece!
Do you by any chance have any drawings (yours or other peoples) that show sectional slices of the Atlantic bow, looking from stem toward stern?
I believe I would like to put the Atlantic Bow on my cutaway but finding sectional drawings of what it looks like for each frame, from say frame 102 forward is proving difficult.
I am holding off doing more detailing in that area till I can gather resources, but if there are none, then I shall go with a standard VIIC.
Keep up the great work! I am impressed!
Cheers!
Christopher

NZSnowman · « **Reply #12 on:** 03 Jan , 2012, 11:02 »

I am sad to say that I have never seen any original German drawings or measurements for the Atlantic Bow.
My Atlantic Bow on U-1308 is base on the Type VIIC bow framing, the few photographs of the Atlantic Bow, and on that I think the German

TopherVIIC · « **Reply #13 on:** 03 Jan , 2012, 12:14 »

Quote

I am sad to say that I have never seen any original German drawings or measurements for the Atlantic Bow.
My Atlantic Bow on U-1308 is base on the Type VIIC bow framing, the few photographs of the Atlantic Bow, and on that I think the German

NZSnowman · « **Reply #14 on:** 03 Jan , 2012, 13:29 »

I am 100% sure that were are plans for the Atlantic Bow but after the war ended they were either lose, or are not viewable on the internet for as. I believe more that they are loss. For example there are about 15,000 set of drawings (plans for the Type XXI) so you can safety say that were are about 10,000 set of drawings for the Type VIIC. I have only seen about 5 original German drawings.

I think the main reason why we are not seeing many original German drawings is that almost all were burn before the Russian arrive.

NZSnowman · « **Reply #15 on:** 14 Apr , 2015, 13:15 »

Here is a updated list of U-boats that we know were modified for underwater refuelling.

U-234
U-244
U-249
U-250
U-310
U-315
U-317
U-481
U-766
U-848
U-858
U-873
U-1023
U-1056
U-1060
U-1165
U-1208
U-1229
U-1233

falo · « **Reply #16 on:** 21 Oct , 2015, 11:39 »

Hi Snowman,

just a question concerning the bow for underwater refueling: How is the piping? From the bow vent to the saddle tank or to the fuel bunker in the lower sections of the pressure hull (fuel oil tank inboard "Treibölbunker 2")?

Thanks in advance and regards
falo

NZSnowman · « **Reply #17 on:** 21 Oct , 2015, 12:27 »

I never see any information on this, so I have no idea

Tore, should have a better idea of the piping might be, but I imagine the Germans keep it very simple.

tore · « **Reply #18 on:** 22 Oct , 2015, 01:27 »

Simon and Falo.
I agree with Simon. I guess the bow fuelling pipe is very simple like the red line on my sketch below. The refuelleing is done by the original fuelling system having a connection right outside the pressurehull.
Tore

falo · « **Reply #19 on:** 22 Oct , 2015, 02:45 »

Hi Tore, hi Snowman,

thanks for the information, it reads well.

Regards
Falo

NZSnowman · « **Reply #20 on:** 22 Oct , 2015, 12:37 »

The only other thing I can add to this.

In real life I imagine the pipe run down the starboard side of the boat, as the inlet was starboard and there virtually no room to run piping on the portside between the conning tower casting and the schnorchel.

Tore, one thing I always wonder about, do you think the Germans put a slight down hill angle into the pipe to drain the line or would they not bother about draining the line?

tore · « **Reply #21 on:** 22 Oct , 2015, 13:01 »

Simon.
Indeed I am pretty sure the piping would be run on starboard side. I don`t believe they would have a drain angle on the pipe. The fuelling would had to be done at a pressure against the submerged compensating head to force the compensating water out of the tanks to accomodate the fuel and I guess it might be they could have an airblowing possibility to blow the line. This is quite common on naval fuelling at sea installations.
Tore

falo · « **Reply #22 on:** 23 Oct , 2015, 11:35 »

Tore and Simon,

find som pictures of boats with underwater refueling bow (IXC and typeseven). Guess you know some of the photos. You have to scroll a little bit down:

http://forum.axishistory.com/viewtopic.php?t=208908

Regards
falo

NZSnowman · « **Reply #23 on:** 23 Oct , 2015, 12:39 »

Here is a updated list of U-boats that we know were modified for underwater refuelling. Now 30 boats

U-234 TRUE
U-243 TRUE
U-244 TRUE
U-249 TRUE
U-250 TRUE
U-310 TRUE
U-315 TRUE
U-317 TRUE
U-481 TRUE
U-766 TRUE
U-776 TRUE
U-806 TRUE
U-848 TRUE
U-853 Not see photo evidence
U-858 TRUE
U-864 TRUE
U-873 TRUE
U-875 TRUE
U-883 TRUE
U-1023 TRUE
U-1056 TRUE
U-1060 TRUE
U-1165 TRUE
U-1208 TRUE
U-1228 Not see photo evidence
U-1229 TRUE
U-1231 Not see photo evidence
U-1233 TRUE
U-1234 TRUE
U-1235 Not see photo evidence

falo · « **Reply #24 on:** 23 Oct , 2015, 14:09 »

Hi Snowman,
thanks for the updated list. Just some "What-if"-thoughts about the late Alberich boats (for example U-1105/"Black Panther" or U-1308) and the refueling bow.

In place of the german navy engineers at the time I would have been a proponent to equip all (late) alberich boats with the rubber coat. Because a boat with this stealth abilities - which only protect them from ASDIC detection by underwater operations - to rig whit a refueling system which works under the surface makes sense.

I have attached two photos of U 1105. One pix is a magnification of the bow (red circle) with a little bit interpolation via Photoshop. IMO the bow does not look like the usual bull nose but the resolution of the picture is not good enough to say with all certainly it is a refueling-bow.

What do you think?

Thanks in advance
falo

NZSnowman · « **Reply #25 on:** 23 Oct , 2015, 22:31 »

I believe there was no boats with both Alberich and the underwater refuelling system together.

The Germans were super keen to update the boats with Alberich and/ or the underwater refuelling system, however, both run into ran into problems during the war. The Oberkommando der Marine must have put a lot of significance into underwater refuelling as Type VIIC's were being modified before the testing was fully finish. The problem was by August 1943 all but one U-boat tanker was lost. So the German gave up the idea underwater refuelling system by mid 1943.

The Oberkommando der Marine planned to use Alberich on the new Type XXI and Type XXII U-boats. But also run to in problems again, as the adhesive was found not to be strong enough to stick the synthetic rubber sheets to the pressure hull and casing of the U-boat. They never really sorted this problem out before the war ended.

NZSnowman · « **Reply #26 on:** 04 Nov , 2015, 12:01 »

Quote from: falo on 23 Oct , 2015, 14:09

Hi Snowman,
thanks for the updated list. Just some "What-if"-thoughts about the late Alberich boats (for example U-1105/"Black Panther" or U-1308) and the refueling bow.

In place of the german navy engineers at the time I would have been a proponent to equip all (late) alberich boats with the rubber coat. Because a boat with this stealth abilities - which only protect them from ASDIC detection by underwater operations - to rig whit a refueling system which works under the surface makes sense.

I have attached two photos of U 1105. One pix is a magnification of the bow (red circle) with a little bit interpolation via Photoshop. IMO the bow does not look like the usual bull nose but the resolution of the picture is not good enough to say with all certainly it is a refueling-bow.

What do you think?

Thanks in advance
falo

Hi Falo

I can now confirm you are right. There is one Type VIIC's with both Alberich and the underwater refuelling system together. U-1105.

In the higher resolution news reel footage video you found, you are clearly see it. Also I rechecked my photo’s I found three photo’s with more evidence.

OldNoob · « **Reply #27 on:** 04 Nov , 2015, 16:18 »

Silly question here.
How did they filter out seawater contaminates from the fuel? OR Was it that there simply was not enough contamination to be an issue?

NZSnowman · « **Reply #28 on:** 04 Nov , 2015, 16:30 »

Quote from: OldNoob on 04 Nov , 2015, 16:18

Silly question here.
How did they filter out seawater contaminates from the fuel? OR Was it that there simply was not enough contamination to be an issue?

From: The U-boat: The Evolution and Technical History of German Submarines. By Eberhard Rossler. Cassell, 1974 (German), 1981/2001 (English)

"Field trails were hold with UD-4, travelling on the surface at a constant speed; a buoy was released with a towing hawser, hose and telephone cable. The hose was filled with air so that towing hawser and telephone cable floated. The buoy was taken aboard the receiving boat, the towing hawser was made fast and the hose was connected. Both U-boats would then go to periscope depth. After the transfer of fuel the two U-boats would resurface simultaneously, the receiving U-boat let go the buoy and turned directly to port."

This sugguct that there was no seawater contaminate, as the hose was full of air.

tore · « **Reply #29 on:** 05 Nov , 2015, 00:54 »

Sea contamination of fuel.
As all the bunker tanks are seawatercompensated so in essence you could say the fuel was always in contact (or contaminated) by sea water. Due to a substantial difference in the specific gravity between the sea water and dieselfuel, approximately 0.87, the seawater is settled in the lower part of the tanks, the fuel to the consumption tanks (daytank/settlingtanks) in the engineroom is taken from the upper part of the bunkertanks. If by accident some of the fuel should be seawater contaminated, the engineers would notice this by the spyglasses on the settling tanks which are fitted with drainage facilities to the dirty fuel oiltank below the floorplating. As Simon are quoting, the fuelling hose was filled with air floating both the hose and phonecable. This air would eventually be forced into the bunkertanks where it collects on top of the fuel. As you do not want this air in your system you have venting possibilities inside the submarine. As previously mention I guess the fuelling hose was emptied by blowing same by air which eventually was vented as mention above.
Tore

OldNoob · « **Reply #30 on:** 05 Nov , 2015, 01:20 »

Great information. Thank you Tore and NZ

falo · « **Reply #31 on:** 08 Nov , 2015, 15:04 »

Hi Snowman,

thanks for the information about U-1105 with alberich and refueling bow. I'am really pleased about it so I have attached a quick photoshop mashup. The screenshots were taken from the higher resolution news reel footage. IMO that's a good photo evidence.

Thanks again and regards
falo

P.S.: The three U-1105 photos you checked are they well known to alberich supporters or do you have never seen before pictures on your HD? If so it would be nice to cast an eye at

NZSnowman · « **Reply #32 on:** 08 Nov , 2015, 15:32 »

All three photo's are from the same time when U-1105 was next to U-802, but from different viewpoints.

Below is the best viewpoints. You can see the radio antenna cable attachment point had been shifted from the centre of the towing eye to the right side of the towing eye to allow for the fuel hose.

falo · « **Reply #33 on:** 08 Nov , 2015, 15:59 »

Thanks a lot, Snowman.

Regards
falo

falo · « **Reply #34 on:** 09 Nov , 2015, 10:48 »

Hi Snowman,

I missed your pdf file you provided on media fire years ago. Could you please post one picture again if possible (see red circle on the preview jpg)?

Thanks in advance and regards
falo

NZSnowman · « **Reply #35 on:** 09 Nov , 2015, 10:57 »

falo, try here.

http://www.u-historia.com/uhistoria/tecnico/articulos/reabastinmer/reabastinmer.htm

falo · « **Reply #36 on:** 09 Nov , 2015, 23:04 »

Hi Snowman,

thanks for the hyperlink.

Regards
falo

falo · « **Reply #37 on:** 28 Jun , 2016, 05:42 »

Hi Snowman,

I know U-1060 ist on your underwater refueling list but do you have seen these pictures? If not, there is another photo evidence.

http://www.ebay.de/itm/U-BOOT-KRIEG-FOTO-U-1060-NACH-GEFECHT-AUF-GRUND-NORDSPITZE-INSEL-FLEINA-NORWEGEN-/112034929969?hash=item1a15cd5d31:g:p1oAAOSwv9hW2t-S

http://www.ebay.de/itm/U-BOOT-KRIEG-FOTO-U-1060-NORDSPITZE-DER-INSEL-FLEINA-NORWEGEN-NACH-SPRENGUNG/112034929976?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D35393%26meid%3D9d985b85c33e49e5b41c04c14f021ac0%26pid%3D100005%26rk%3D1%26rkt%3D6%26sd%3D112034929969

According to the text U-1060 was sunk by the crew after an air raid.

Regards
falo

NZSnowman · « **Reply #38 on:** 30 Jun , 2016, 14:59 »

Quote from: falo on 28 Jun , 2016, 05:42

Hi Snowman,

I know U-1060 ist on your underwater refueling list but do you have seen these pictures? If not, there is another photo evidence.

http://www.ebay.de/itm/U-BOOT-KRIEG-FOTO-U-1060-NACH-GEFECHT-AUF-GRUND-NORDSPITZE-INSEL-FLEINA-NORWEGEN-/112034929969?hash=item1a15cd5d31:g:p1oAAOSwv9hW2t-S

http://www.ebay.de/itm/U-BOOT-KRIEG-FOTO-U-1060-NORDSPITZE-DER-INSEL-FLEINA-NORWEGEN-NACH-SPRENGUNG/112034929976?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D35393%26meid%3D9d985b85c33e49e5b41c04c14f021ac0%26pid%3D100005%26rk%3D1%26rkt%3D6%26sd%3D112034929969

According to the text U-1060 was sunk by the crew after an air raid.

Regards
falo

Hi falo

Thanks for the information & photo. The list in the link is old and out of date. Below is the the current list

U-Boat Number
234, 243, 244, 249, 250, 310, 315, 317, 481, 766, 776, 806, 848, 853, 858, 864, 873, 875, 883, 1023, 1056, 1060, 1105, 1165, 1208, 1228, 1229, 1231, 1233, 1234 and 1235.

Author Topic: Atlantic Bow modified for underwater refuelling (Read 11295 times)

Nevermind4712

TopherVIIC

TopherVIIC

TopherVIIC