TABARKA, i Relitti.

[Francesco De Domenico]

Jean-Pierre ha provvisoriamente identificato il sommergibile DESSIE' tra i relitti del Golfo di Tabarka, e ha comunicato la notizia all'ambasciatore d'Italia in Tunisia.

Edited September 7, 2015 by Corto Maltese
Corretto post

[Corto Maltese]

Ed ecco la mail inoltrataci da Jean Pierre con cui ci comunica questa importante notizia. La prudenza in questi casi è d'obbligo quindi non vi nascondo che attendo, con grande interesse, il rapporto che l'amico Misson redigerà dopo aver ispezionato il relitto.

 

 

"This is  to confirm that one of the many wrecks off Tabarka, Tunisia, is:

 

ITALIAN SUBMARINE DESSIE'

 

Position:   37°  04'  N         8°  52'  E (l'indicazione dei secondi è stata volontariamente omessa n.d.r.)

Depth ca.:  70 m

 

See Wreck.eu:  http://www.wrecksite.eu/wreck.aspx?142208

 

The attached picture shows a circular opening, larger than the drain holes, under the Gun Platform. It correlates with the large circular opening showing on the sonar image. This aperture seems to have only been on the hull of the 17 submarines of the  ADUA Class. No other submarines (of other Italian "Class" or of any other origin)  had such a large circular opening under the gun platform. All features and fittings on a submarine are symmetrical on Port and Starboard. With a good matching of the vintage picture against the sonar image and considering that submarine DESSIE' was operating in the area at the time she disappeared , it seems safe to assert the wreck is of this submarine. Diving the wreck is being planned".

 

Attachments:

 

Tabarka wrecks area:

 

 

 

Sommergibile Dessié:

 

 

 

Dessiè 2G:

 

 

 

Circular shape side of gun:

 

 

 

Large Circular Aperture Platform:

 

 

Edited September 3, 2015 by Corto Maltese
Sostituita immagine

[Corto Maltese]

News of the day from Tabarka:

 

 

"Pic. 1  The wreck as  "shown"  by the sidescan sonar during the sweep in Otober 2014.

Pic. 2  Notes.

Pic. 3  The zone of search , where so many wrecks have been sonar-located. Only one wreck is shown on nautical chart Oceangrafix 52200.

Pic. 4  View of the coastline with the position of the area where the wrecks of 3 Submarines and of Destroyer HMS QUENTIN  have already been sonar-located. A CargoShip, an MTB  and several other wrecks have been located but not identified, yet. 

Pic. 5  Picture of the Italian submarine  RM  DESSIE'  presumed to be the wreck on Pic. 1. For the details leading to this assumption, see earlier mails.

Pic. 6  Table showing the different types of Italian submarines (from Storia Militare, n° 11 , 2013)            

Pic. 7  List of all 16 sisterships of RM Dessié (from Storia Militare) See Submarine RM Dessié on Internet for articles on the operations and the fate of this submarine. The sonar image Pic. 1  shows a submarine heavily listed to Port.

Heading ca.  40°. Depth ca.  70 m.  Flat seafloor. Probably  Sand / Mud. The snapshot does not show a good portion of the wreck due to the target being in what is called the "water column" (the corridor immediately under the sonar transducer): in this narrow corridor the sonar is blind. An additional  "side passage"  would be required to see the wreck in full. The sonar equipment used was TRITECH, Starfish 450. A better image could be obtained with a Starfish 452 or Starfish 900. The figures 450/452/900 relate to the frequency used. The higher the frequency, the better the "definition" of the image (but lower is the range !). The Gun is clearly visible. The bows are heavily damaged : this would indicate the vessel fell foul to a mine. As we now know, this area was a naval minefield, laid by the germans in 1942-1943. This is clear not only from the many wrecks but also from the remains of the mine-anchoring gear, still on the seafloor. Steel cables and chains, together with cube-shaped anchor blocks

can be seen on the sonar recordings, in large number and at regular interval.

Pic. 8  The submarine which has been identified as British U Class (no Name / Pennant Number, yet).

Pic. 9  A third submarine, yet to be identified. At first glance this one would also be Italian because of the Hydroplanes, still in the upturned position: the tips are parallel to the level of the deck. On british submarines, of any Class WWII, the tips of the Hydroplanes were triangular and protruded somewhat above deck level: Pic. 10

 

Attachments:

 

1)

2)

3)

4)

5)

6)

7)

8)

9)

10)

 

Jean Pierre Misson, Tabarka, Tunisia. August 27, 2015".

 

 

[Naumachos]

Questo si che è un 3d interessante ! Finalmente riesco a leggerlo,gran lavoro davvero,il tutto a profondità assolutamente fattibili anche respirando aria.

[Corto Maltese]

"Irrespective of the name that will eventually be found for this submarine, this vessel is definitely of Italian design: the CLASSE 600.
A preliminary correlation exercise has been done, using the vintage picture of RM Dessié: the matching is conclusive. To differentiate this wreck from the many other wrecks in the area, it has been identified as 2G: Sonar Search 2 (October 2014), the Seventh Wreck (A-Z). When judgeing the validity of this study it is essential to keep in mind two important points:

1. The sonar snapshots, printed out from a sonar recording are nowhere near as sharp as what can be seen on the display of the computer playingback the recording. However meticulous is the adjustment of the sonar's software (Gain,Contrast,Range,Colour), the Printout will never be as good as the display on the computer...;
2. The sonar images are of vessels that have been on the bottom of the sea for about three quarters of a century: the metal has been severely eaten away. In the particular case of submarines, the body was a combination of a (thick) metal plating for the Pressure Hull and a (thinner) metal plating for the Outer Casing and Conning Tower. What we now see on the sonar image is in no way what can be seen on pictures or what can be found on the drawings. In fact the sonar image only shows what remains of the thick and solid parts of the structure, after the thin parts have disappeared due to rusting and decay over time. For this reason, the deciphering of sonar images can be rather difficult, at times. In all cases: it requires a lot of Time to patiently view the images and it also needs repeated, playback sessions, at intervals. A fresh mind can see things that were totally missed in earlier viewings.

Jean Pierre Misson, Tabarka, Tunisia. September 5, 2015".

 

Attachments:

 

 

Dessié Large Drain Hole:

 

 

 

2G Bows damage:
 

 

 

2G The Larger Drain Hole:
 

 

 

Dessié Correlation:
 

 

 

600 Class Drawings:
 

[Long John Silver]

Pubblico per conto del nostro socio Jean-Pierre Misson:

 

E' stato localizzato (solo dal sonar) fra altri nuovi relitti : un sommergibile Italiano.

 

Position   :      37°  04'  41"  N        8°  52'  31"  E

 

Questo è stato Domenica 13 Settembre : il secondo sweep di quest'anno e non è completata la ricerca...

Ci saranno sicuramente altri ritrovamenti.
In allegato l'immagine della parte posteriore dello scafo con le due cupole dietro la torretta.

 

 

e una Correlazione con un disegno costruttivo della Classe 600 (Storia Militare , n° 11 , pagina 10))

 

 

Il design è tipico dei soli sommergibili Italiani. Pic.3 , Pic. 4  (Storia Militare , pagina  49)

 

 

 

Con le foto d'epoca e  i disegni costruttivi si tenterà di  identificare / proporre un nome per questo sommergibile.

 

JPM

Note :

There are two other submarines not fully identified yet , but probably Italian too. These are shown on  Pic. 5 and Pic. 6

 

 

Another two submarines are decisively British because of their short Outer Casing , Aft.

 

This brings the total of wrecks identified as "submarine" to five , in the area. Pic. 9

 

 

Diving these wrecks is a challenge because of the depth.

 

[Long John Silver]

Pubblico una mail appena arrivata dal nostro socio JP Misson in missione a Tabarka.

 

For information only .

 

Four Sidescan Sonar searches have been conducted off Tabarka , Tunisia : in September and October 2014 and in July and September 2015.

To this date , the recordings have revealed the wrecks of several submarines from WWII:
The loss of these submarines is due to naval mines : the bows of all vessels are severely damaged.

 

Sonar Image of submarine 2F 37° 04' 32"  N 8° 52' 34" E

 

Sonar Image of submarine 2G (37° 04' 45" N 8° 52' 35" E  (presumed Italian)

 

Sonar Image of submarine 3T     37° 04' 31" N       8° 52' 34" E  (presumed British)

 

Sonar Image of submarine 40     37° 04' 36" N       8° 52' 35" E  (presumed British)

 

Sonar Image of submarine 4V    37° 04'  44" N       8° 52' 32" E

 

Sonar Image of submarine 4B'    37° 04' 41" N        8° 52' 31" E  (confirmed Italian)

 

All these wrecks are at a depth rangeing from  72 m  to   77 m.

 

While waiting for the day when a visual approach will be possible , efforts will be made to obtain better Sonar Images and possibly some Photographs using a Drop CCTV Camera. 

Note : The wrecks have been temporarily identified as   2F , 3T , 4V  etc. The Prefix is the Search Number , the Suffix is the position of the wreck (A-Z) during the search.
Wreck 2G was located during Search 2 and is the 7th wreck appearing on the recording.
The list will not prove to be (possibly) wrong on more than one count.

 

[Naumachos]

Lo so che è pura fantasia,ma per fare questi relitti sono disposto a scendere via mare a Tabarka da Genova,peccato ci siano problemi burocratici per le immersioni senza diving.

Comunque un gran lavoro che meriterebbe di essere completato con una documentazione tramite video e foto,bravo Misson.

[Corto Maltese]

Riporto in calce al presente post una mail inoltrataci, il 25.09.2015, dal socio Jean Pierre Misson: 

 

"Four Sidescan Sonar searches have been conducted off Tabarka, Tunisia: in September and October 2014 and in July and September 2015. Among other wrecks, the recordings have revealed several submarines. The loss of these submarines is due to naval mines, WWII: the bows of all vessels are severely damaged. The position of the minefield and of most wrecks is shown on Pic. 8:

 

Pic. 1  Sonar Image of submarine 2F     37° 04' 32"  N      8° 52' 34"  E:

 

 

Pic. 2  Sonar Image of submarine 2G    37° 04'  N      8° 52'  E  (presumed Italian) [1]:

 

 

Pic. 3  Sonar Image of submarine 3T     37° 04' 31" N       8° 52' 34" E  (presumed British):

 

 

Pic. 4  Sonar Image of submarine 40     37° 04' 36" N       8° 52' 35" E  (presumed British):

 

 

Pic. 5  Sonar Image of submarine 4V    37° 04'  44" N       8° 52' 32" E:

 

 

Pic. 6  Sonar Image of submarine 4B'    37° 04' N       8° 52'  E  (confirmed Italian) [1]:

 

 

Rev. 24-9: Addendum: Pic. 7  Sonar Image of submarine 4M'   37° 04' N       8° 52'  E  (confirmed Italian)[1]:

 

 

Pic. 8

 

 

All these wrecks are at a depth rangeing from  72 m  to   77 m. While waiting for the day when a visual approach will be possible, efforts will be made to obtain better Sonar Images and possibly some Photographs using a Drop CCTV Camera.  

 

Note : The wrecks have been temporarily identified as   2F , 3T , 4V  etc. The Prefix is the Search Number, the Suffix is the position of the wreck (A-Z) during the progression of the search. Wreck 2G was located during Search 2 and is the 7th wreck appearing on the recording. The list should not prove to be (possibly) wrong on more than one count. To date, only one surface vessel has been identified from her sonar image: this is HMS QUENTIN, now resting in position 37° 04' 44"  N  8° 52' 33"  E. Putting a name on each wreck will require much time and effort".

 

[1] I secondi sono stati volontariamente omessi.
 

[Corto Maltese]

Jean Pierre Misson ci ha inoltrato questa mail da Tabarka il 28.09.2015:

 

"This is to confirm that recent sidescan sonar searches have revealed an exceptional concentration of wrecks off Tabarka, Tunisia. The evidence is on the recordings of these sweeps.  Aside from the wreck of Destroyer HMS Quentin, there are many more wrecks of all kinds of surface vessels. Of particular importance (because they still hold their entire crews) are seven submarines. Three of them have been recognised as being of Italian construction and another three are presumed British. All these wrecks show damaged bows and steel cables, chains and anchors blocks can be seen on the sonar recordings. The place has been a naval minefield installed by a German Schnellboot Flotilla, based in Bizerte from December 1942 to May 1943.

 

Pictures: 

 

Pic.1  The area with many wrecks: the position of the minefield WWII.

 

 

Pic.2  Naval mines moored at a depth to obstruct passage of submarine:  

 

 

Pic.3  An Italian submarine, identified from Domes on the deck:

 

 

Pic.4  A British submarine, identified from a short Casing, aft:

 

  

 

It is believed there is no similar place in the Mediterranean with such a number of submarines, all lying in a very limited perimeter. The only but great difficulty is the depth: in the range  72 - 77 m. Scuba Diving in Tunisia is strictly regulated: no diving outside of a Dive Club and no Club will allow a dive beyond 40 m. Therefore, some other solution is to be found to visually approach these wreck".

 

[Corto Maltese]

Abbiamo ricevuto in data 29.09.2015 la seguente mail di Jean Pierre:

 

 

"A summary of data for the seven wrecks identified as "Submarine", as at 29/9/2015. Sonar images in earlier posts, depth: 70 - 77 m".
 

T A B A R K A



Submarine 2F  37° 04' 32" N 8° 52' 34" E

Submarine 2G  37° 04' --" N 8° 52' --" E (presumed Italian)[1]

Submarine 3T  37° 04' 31" N 8° 52' 34" E (presumed British)

Submarine 40  37° 04' 36" N 8° 52' 35" E (presumed British)

Submarine 4V  37° 04' 44" N 8° 52' 32" E

Submarine 4B' 37° 04' --" N 8° 52' --" E (confirmed Italian)[1]

Submarine 4M' 37° 04' --" N 8° 52' --" E (confirmed Italian)[1]

[1] I secondi sono stati volontariamente omessi.

[Long John Silver]

Inoltro per conto del nostro socio JP Misson:

 

Italian Submarines : the typical DOMES on Deck

 

From 7:08 to 7:10

 

https://www.youtube.com/watch?v=Bem-_t6Q_2o

 

 

[Long John Silver]

Pubblichiamo un aggiornamento del nostro socio JP Misson a Tabarka:

 

TABARKA Wreck 2G Confirmed Italian

 

For infomation only.

 

Earlier Posts (of this thread NDR) hinted at the possibility for this wreck to be the Italian submarine RM Dessié .
This was only based on a larger-than-normal Drain Hole seen on the sonar image and on vintage pictures of this submarine (and of no other , except possibly RM Adua)
One more detail confirms this is an Italian submarine:
The sonar image shows a Dome on the Fore Deck , between the Gun and the Hydroplanes.

 

Domes on the decks (Fore and Aft) were a feature specific to submarines of Italian construction (WWII era) Wreck 2G  is an Italian submarine.
This reinforces the case for this wreck to be RM Dessié.

 

http://www.xmasgrupsom.com/Sommergibili/Dessie.html

 

http://www.wrecksite.eu/wreck.aspx?142208

 

https://www.youtube.com/watch?v=H3Sk4FZFLI0

 

The Dessié is said to have been lost to an attack by HMS Quentin and HMAS Quiberon, off BONE (today ANNABA) on December 2nd , 1942.
The Allies had already landed in nearby Algeria and Annaba is just a few miles from Tabarka.
The nearest Italian base was Bizerta and had RM Dessié been only hurt and had wanted to take refuge there: she would have hugged the shore.
The wreck shows severe damage to the bows but it remains to be seen if this is due to hitting a mine or to some other type of damage damage suffered during the attack by the British destroyers off BONE (Annaba).

There seems to be some questions about the date when naval mines were first laid a few miles East of Tabarka. It could be that naval mines were planted in that zone earlier than December 16 , 1942 when the first sorties of German E boats out of Bizerta are reported in naval archives and in books...

If it were confirmed that the wreck of this Italian submarine (2G) is indeed RM Dessié ...then a remarkable coincidence would come to light : HMS Quentin (the Destroyer that attacked RM Dessié off BONE (Annaba) on December 2, 1942 ) ....came to rest on the seabed about one hundred meters from her , exactly one year later:  on December 2  1943!

 

The wreck of HMS Quentin (last picture) is in position    37°  04'  44"  N     8°  52'  33"  E

http://www.aidmen.it/topic/188-jean-pierre-misson-e-i-relitti-del-golfo-di-tabarka/

 

[Long John Silver]

Inoltro dal nostro socio JP Misson:

 

TABARKA Wreck 5P is an Italian Submarine

 

The sonar search on October 6 has revealed yet another wreck of a submarine in the area off Tabarka , where a german naval minefield had been planted  Dec.42 - May 43.

The attached Pictures 1 and 2 are the sonar images of this wreck. They are complementary to one another.
Picture 1 is the Fore end , while Picture 2 is the Aft portion of the vessel.

 

 

 

The submarine is slightly listed to Port but is otherwise on an even keel. The bows look damaged or altogether missing , the result of hitting a mine.

The submarine is Italian for the following reasons :

-The Anchor (stockless type) is seen on the Port side of the hull (Pic. 3) : this was standard for all the   Italian units of the "Classe 600". (Very few Italian submarines had the anchor on the Starboard side: these were of some other "Classe" :  Settembrini , Mameli , Argo).
Most British submarines operating in the area were of the U Class:  the anchor was on the Starboard side.

 

This wreck is in position: 37° 04' 47" N  8° 52' 36" E
Depth circa 70 - 75 m

 

 

-Some Domes can be seen on the Aft deck (Pics. 2 , 6) :  this is a very specific Italian design : no other submarines of any other origin had such Domes.

 

 

 

 

 

5P is the fourth submarine , found in this area , to be confirmed Italian : the other three are : 2G , 4B' , 4M'.

They all lie within the perimeter shown on Pic. 7.

 

5P indicates the wreck is on Sonar Recording 5 (Oct. 6 , 2015) and shows as the 16 th Target (A-Z).
The Sonar Recordings are numbered

 

1. September 2014
2. October 2014
3. July 2015
4. September 2015
5. October 2015

 

 

 

[Long John Silver]

Inoltro da parte del socio JP MIsson:

 

OUTLET for BILGE PUMPS on Submarines

 

 

For information only.

For some time the Large Circular Apertures seen on vintage pictures of submarines (whether Italian or British) had remained a question mark.
Many  pictures show one , sometimes  two , odd  openings on the side of the hulls. These apertures are generally not aligned with the row(s) of drain apertures on the casing. An illustration of such "special" apertures is on the attached Pic. 1 (Italian submarine  RM DESSIE') and Pic. 2 (British submarine HMS AFFRAY , courtesy P. Hulme). 
The apertures are positioned in the Fore and the Aft portions of the craft. They are for the Outlet of the Bilge Pump(s) and are believed to be duplicated : Port and Starboard. This finding is the result of a research that started when a larger-than-normal circular aperture was noticed on the sonar image of wreck 2G , off Tabarka. Pic. 3 , 4.

 

It led to believe that the wreck is of Italian submarine RM DESSIE' as the only vintage picture showing such a larger-than-normal circular aperture , in that precise position , is a picture of the DESSIE' !

Plans are being made to dive the wreck in the summer of 2016. Although the bows look damaged it is hoped the name , in raised letters , will be found.
A few letters of it would suffice.

Note :
When not apparent as a distinct aperture in the casing , the outlet of a  Bilge Pump is simply taking advantage of an existing standard Drain Aperture as shown on Pic. 5 (RM UARSCIEK , courtesy E. Bagnasco)