German Sonar on Italian Vessels – Pt. 3

German Sonar on Italian Vessels – Pt. 3

In the third and, for the moment, final part of this mini series on the use of German S-Gerät sonar on Italian vessels, here is a list of the vessels which had it installed, or were scheduled for installation, as of 28 February 1942. The list excludes Antonio da Mosto, which had been sunk by that date (see this link and this link and this link).

The list is fairly self-explanatory. I am using the Italian abbreviations, so ‘Ct’ stands for Cacciatorpediniere – Destroyer, and ‘Tp’ for Torpediniere, Escort Destroyer or Torpedo Boat. The destroyers listed are an interesting mix, and five were going to be assigned to the Italian fleet following the installation of the S-Geraet. They included the older Navigatori class, of the late 1920s, and the most modern fleet destroyers of the Soldati class.

The Torpediniere are also a bit of a mix, primarily Spica class, but with two older vessels included, the San Martino and the Calatafimi, both of which dated back to WW I destroyer designs and had only recently been downgraded to Torpediniere status. Unlike the destroyers, most of the Torpediniere were going to be assigned to specific stations, Sicily (4), Libya (3), Greece (2), Rhodes (2), Naples (1), and the escort group (1).

A number of destroyers and Torpediniere have no destination allocated to them.

In the table, ‘DC’ stands for depth charge. For Italian depth charges installed, where it reads ‘0 16/50 12/100’, this means ‘no depth charge launcher, 16x50kg depth charges and 12x 100kg depth charges’. For background on the Italian depth charges, please see this link. I am not certain the information in the report is fully correct, but it is given as is.

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Destroyers Usodimare and da Noli in port, late 1930s. The picture shows well the range finder, rounded bridge house, and the twin-turret with its 4.75” (12cm) guns. Courtesy Wikipedia.

 

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The obsolete destroyer San Martino entering a port. Courtesy Wikipedia

Apart from the naval vessels, some auxiliaries were also equipped with the S-Geraet, for harbour defense in La Spezia and Taranto, and two motor sailing vessels (Motoveliere) for serving with the submarine defense school at La Spezia, to train new personnel. The only vessel where the future port of service isn’t given is the Cyprus.

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Mystery Sub Loss?

Mystery Sub Loss?

Showing that German S-Gerät was not perfect, here is a report by Regia Marina Tp. Orsa about an attack and confirmed sinking, that cannot be corroborated and therefore has to be dismissed as an error.

The Orsa-class was a class of four torpedo boats, developed from the Spica-class, with a clearer focus on anti-submarine warfare and escort duties than the earlier boats. Two of the four survived the war (the other two were scuttled at the Armistice in September 1943), modernized, re-designated as frigates, and served the Marina Militare until the mid-1960s.

In the records of the German navy command South (Marinebefehlshaber Süd – Admiral Weichold), there’s a telegram from a chap called Ahrens, who was assigned to the Regia Marina‘s torpedo boat Orsa, about a successful attack by Orsa on a submarine. Based on the report about the attack in the same file, Orsa was equipped with the German sonar equipment and depth charge launchers (see this older post), and Mr. Ahrens was an offiicial responsible for the final hand-over of this equipment to ships’ crews, and participated in the mission.

The text of the telegram is as follows:

131 Trapani 725 34 TF 8 1941

German Naval Command, Navy Ministry Rome

Entered Trapani with Orsa on 8 January 17.30 hours. Submarine attacked with visual success. Depart 8 January [should be 9?] 08.00 hours for Messina. Request information of Fürbringer Berlin. Ahrens.

The separate report states that the attack happened on 7 January, at 09.45 hours. The target was identified as a submarine because of the very clear echo. The visual confirmation of success consisted of an oil spot on the surface, coming after a depth charge attack, an air bubble, and wooden pieces coming up.

RN Procione

Orsa-class torpedo boat Procione underway.

Now here’s the puzzle. No submarine has been reported lost in the area on the 8 January or on the preceding days. One submarine went missing during this period, HMSub Triumph, but that was far away from Trapani, in the Aegean. More detail on this can be found at this link. HM/Sub Triumph was quite an interesting boat, having been involved in Operation FLIPPER, the raid on ‘rommel’s HQ’ (actually offices of the Chief Quartermaster Panzergruppe). And her successor in name was busy again in Libya during the intervention post-Ghaddafi…

As can be seen, even though visual confirmation of the supposedly successful attack was obtained, there was no submarine. One boat that was in the area just prior to the attack was the famous HMS Upholder, which on 5 January 42 had sunk Regia Marina sub Ammiraglio Saint Bon during a supply mission for North Africa, but she had returned to Malta.

Sinking of HM Submarine P.38 – 23 February 1942

Sinking of HM Submarine P.38 – 23 February 1942

Background

This is only indirectly related to Operation CRUSADER, but of interest nevertheless because it shows the increasing sophistication of Italian escort vessels which happened around the time of the end of the operation, and which probably contributed somewhat to 1942 becoming the worst year for losses in the Mediterranean, with a total of 13 of HM Subs lost, compared to 9 in 1940 (admittedly in just over six months), and 11 each in 1941 and 1942. I have added information on the Italian convoy on 28 May, based on the entry in the Seekrieg website.

HM/Sub P.38

P.38, under the command of Lieutenant R.J. Hemingway RN DSC, was sunk by Tp Circe (Tp = Torpediniere – torpedo boat, a class of light escort destroyers), which sank or participated in the sinking of four Royal Navy submarines, HM S/M Grampus on 16 June 1940, HM S/M Tempest and P.38 in February 1942, and HM S/M Union in July 1942. Circe herself was lost on 27 November 1942 in a collision with auxiliary cruiser Citta di Tunisi. Lt. Hemingway was probably awarded his DSC on 20 December 1940 for  what was believed to be a successful action against an Axis submarine (either U-58, or Italian submarines Veniero or Otario) in the Bay of Biscay, while serving on HM S/M Tigris under Lt.Cdr. Bone, DSO, DSC. In reality however Tigris did not sink the target, whichever of the three it was. His previous command was HM S/M H.31, which was lost with all hands on 19 December 1941 in the North Sea.

Hms p38 submarine

HM/Sub P.38 underway. Wikipedia.

Attack Operations

P.38 was sunk while trying to attack one of the big convoys of early 1942, in this case the third major operation of the year, convoy K.7. It consisted of two separate convoys of six merchants each from Messina and Corfu. The convoys were the fast motor vessels Unione, Monginevro, Ravello (all in convoy 1), and Monviso, Lerici, and Giulio Giordani (convoy 2). They were escorted by destroyers in direct escort (Ugolino Vivaldi, Lanzerotto Malocello, Nicolo Zeno, (all Navigatori-class), Premuda (captured Yugoslav Dubrovnik), Strale (Freccia-class), – convoy 1; Antonio Pigafetta (F), Emanuele Pessagno, Antonio Usodimare, (all Navigatori-class) , Maestrale, Scirocco (both Maestrale-class) – convoy 2) and also by two squadrons of heavy escorts, those of the  old battleship Duilio with the Soldati-class destroyers Aviere, Ascari, Geniere, Camicia Nera, and the heavy cruisers Gorizia and Trento, the light cruiser Giovanni della Bande Nere, and the destroyers Alpino (Soldati), Antonio Da Noli (Navigatori), and Alfredo Oriani (Oriani/Poeti-class).

Convoy 1 was escorted by the Spica-class torpedo boat Pallade, and convoy 2 by Spica-class torpedo boat Circe. Commander of the close escort of convoy 2 was the Captain of the destroyer Antonio Pigafetta.  It appears that only Circe and Pallade were equipped with the German S-Gerät sonar and German depth charge throwers (and maybe also depth-charge rails, since references to depth charges used on Circe use two German separate designations).

 

Torpediniere Circe Marina Militare

Spica-class Torpedo Boat Circe with dazzle camouflage, which she carried by May 1942. USMM

Lt. Commander Palmas’ Report

Here’s the report of her captain, Capitano di Corvette (Lt.Cdr.) Palmas, which is held in the captured German records section in NARA. It can be found in the files of the German Naval Attache in Rome.

GKDOS 1706/42

28 March 1941 (sic!)

SECRET COMMAND AFFAIR!

REPORT ABOUT THE SINKING OF AN ENEMY SUBMARINE BY TORPEDO BOAT “CIRCE” ON 23.2.42 – ACCORDING TO STATEMENT BY COMMANDER K.KPT.PALMAS

CIRCE escorted a convoy of 3 steamers on the way to Tripolis. Calm sea. Light swell. Speed 14 knots.

Northwest of Cape Misurate an echo was reported at 1014 [hours] in 46 degrees, 1,800 metres. Bearing wanders out quickly. Signal to convoy to turn to port.

Boat [CIRCE] turns into the bearing, increases speed to 18 – 20 knots and moves across the target. At around 1,000m the periscope is sighted at the position of the echo. With 16 knots moved onto it and dropped six depth charges from rails and four from throwers into the location of the dive which was indicated by air bubbles. Depth setting 70 metres. Shortly after the submarine surfaces with heavy list to stern, it had apparently used pressurised air [emergency surfacing]. Other boats [escorts] and planes open fire and throw depth charges, in some cases in front of other boats. One Italian rating is killed by friendly machine-gun fire. This makes an orderly attack by CIRCE impossible. After the other boats have been called off, CIRCE again receives an echo from the by now again submerged submarine. This resurfaces shortly after like a dolphin with running screws and drops 45 degrees listing to prow into the depth. A lot of oil and air bubbles come up, which only slowly reduce. Apart from that parts of the interior fittings (polished cupboard door, table top), one bag with flags and body parts (lung) drift up.

Boat remains 1.5 hours on the scene of the attack. Echo shows the same location until the last. Water depth 350m. The echo is probably caused by the continuing rising of oil and the still escaping air.

In his formal report to Supermarina, the Italian admiralty, he also analysed the performance of the attack. Below is the section on lessons learnt.

  1. March during lively sea during the night 22 to 23 February has taxed the ship’s hull very much, especially while marching direction 180 degrees.
    Three cracks occured at the movement gap [Dehnungsfuge], which is situated in the centre of the boat, between machinery centre and the ventilators of boiler room 2.
  2. In contrast to the attack on 13 February [on HM S/M Tempest, which was sunk], this attack on a submarine was carried out almost with lightning speed, with the intent to prevent the submarine, which was already lying ready to attack, from carrying this out and to then hunt and destroy it.
    The second task, far more important by comparison to the first, was achieved almost immediately. The convoy could, because of my signals, turn away 90 degrees to port, and thereby move away from the danger zone. The second task was then resolved shortly after, by the almost immediate dropping of all depth charges, which were set at 75 metres depth [sic!] from the rails and throwers.
    The explosion has certainly hit the submarine which was in rapid dive. It was so strong that the enemy commander could do nothing else but surface immediately and give pressurised air on all the tanks.
    The second and last attempt by the submarine to surface failed, and it dived forever.
  3. The attach was carried out based on the information received from the S-Geraet, the prior sighting of the periscope, and the air bubbles which remained on the surface when the submarine dived rapidly. These visible signs led me to drop all depth charges at once, even though by this I partially violated existing regulations. 11 depth charges were dropped. I found it not useful to undertake further depth charge drops during the later phases of the search since the proof I had seen and collected left not the slightest doubt about the result of the attack. The parts of the interior fittings of the submarine and the human remains prove beyond any doubt the destruction of the submarine. During the two unsuccessful attempts to surface the tower was closed and nobody came out. The small bag with flags was probably inside the tower under the hatch, inside the pressure vessel.
  4. The behaviour of the crew was again commendable. The rapidity of the attack has excited the crew beyond belief.
  5. The explosion of a depth charge packet is extremely strong. The hull of the torpedo boat has vibrated noticeably, but not too much, because I carried out the attack at a speed of 15 knots.

It is clear from this account that P.38 and her crew never stood a chance. The Italian commander made all the right decisions (and risky ones – emptying his depth charge racks could have landed him in trouble if P.38 had survived the first attack), he had advanced detection systems that allowed him to find the enemy (and I wonder if 10th Flotilla on Malta was aware of this – does anyone know?), and his relentless initial attack doomed the submarine.All 32 hands on her were lost. May they Rest in Peace. You can read a bit of background on one of her crew, 22-year old Clarence Durnell, at this link. Before rejoining the convoy escort, Circe made a final gesture to the fallen, according to the report of her commander:

Before I finally move off, I cross the site of the sinking at slow speed and and offer the fallen honourable recognition with the whole crew on combat stations.

The convoy arrived in Tripoli without any losses, and brought much needed reinforcements for the Axis forces in North Africa, allowing them to build up strength for the Gazala battles in May 1942, the conquest of Tobruk, and the advance to El Alamein.

Many thanks for Dili from the Comando Supremo forum for his comments and corrections.

German Antisubmarine Equipment on Italian Vessels

German Antisubmarine Equipment on Italian Vessels

Background

In the files of the German naval command in Italy held at NARA, I found something completely new to me (as one does).  In autumn 1941 the German navy had started to equip Italian escort vessels withASDIC active sonar equipment (S-Geraet) and depth charge launchers (WBW).  The priority was apparently given to equipping escort units in the Aegean, where allied submarines had been active and successful for a while.  In December 1941, the Kriegsmarine established a sub-hunting flotilla at Piraeus to be able to contribute to the Regia Marina’s effort.  Italian vessels were equipped with the German sonar when they went into wharf in Italy for general maintenance, i.e. they were not pulled from service to have this equipment fitted. My guess is they were stretched so thin already that this would not have been possible.  Until the German sonar came along, the Italian vessels had to use passive listening devices to locate submarines.  One is tempted to conclude from the significant successes achieved by Allied submarines that these were not very good at fulfilling their purpose.

The sonar equipment on the Italian vessels was operated initially by German sailors, while Italian naval personnel was attending the Kriegsmarine anti-submarine school at Gotenhafen. One of the first Italian units to be outfitted with the German equipment was the older destroyer Alvise da Mosto. She was sunk in a surface engagement with the Royal Navy’s Force K from Malta on 1 December 1941, off Tripoli (see this older entry). It had only been outfitted at the Italian navy shipyard in Fiume two weeks beforehand, it appears.

Alvise Da Mosto5 da La difesa del traffico con l AS vol VII

Alvise da Mosto underway in the first months of the war, probably off Taranto. USMM.

Report for the Kriegsmarine

A report by the two surviving German sonar operators found its way into the files of the German naval command, and is preserved at NARA.  Both of these men were re-assigned to other Italian escort vessels and when on the Spica-class torpedo boat helped sink HM Submarine Tempest on 13 February 1942 (this article describes the incident). In this attack, Ordinary Seaman Maidenoff being credited with re-establishing her location when she was submerged.

The report must be from after March 1942, since it refers to the death of Commander del Anno who was lost when his destroyer went down in a gale  at the 2nd battle of Sirte. While probably not a completely accurate report, it is an interesting eye-witness statement. Below is a translation of the report.

Report about the Actions of the Destroyer “Da Mosto” from 18 November 1941 to 1 December 1941 based on the Statements of the two Rescuees Petty Officer Rublack and Ordinary Seaman Maidenoff

 

German listening crew consisting of:

Petty Officer (Bootsmaat) Rublack

Able Seaman (Matrosengefreiter) Hartmann

Able Seaman Macar

Ordinary Seaman (Matrose) Maidenoff

Ordinary Seaman Retter

During the move from Fiume to Pola on 18 November a submerged Italian submarine located at 4200 [metres].  Echo remained good until the end. Speed 16 knots.

During the move Pola -Tarent on 24 November one steamer escorted. Defect on the motor cinema [screen of the sonar, I guess]. Mirror running too slow, therefore no correct distance.  Reason: strong variations in net. Turning the unit off leads to only slight improvement.

Around 0700 [hours] perfect echo ranged at 320 degrees. Distance could not be fixed. Boat [this refers to Da Mosto] zig-zags at high speed, steamer turns away.  This location was very probably an enemy submarine since a few hours later  an attack occured on another steamer in the same area (statement by the commander).

Enter Taranto on 25 November around 1500. With help from a German mechanic the cinema motor is changed against another one from the installation of another boat.  The work is completed shortly before the boat leaves harbour.

On 26 November 1500 left harbour with a tanker for Trapani.  In the Messina Straits submarine alarm raised by another boat. Search by Da Mosto without result.

At the southern tip of Sicily an unknown mine barrier was well located.  Proceeded according to guidance by S-Geraet.

28 November at 2000 entered Trapani with tanker.

30 November at 0300 left harbour with tanker on western route to Tripoli.  On the way location of a floating mine, a buoy, and a wreck.  Furthermore three French coastal vessels were located on 3,600 to 3,800 metres, which were only then recognised from the bridge.

During the course of 1 December attacks by English bombers occured in several waves. The tanker was hit in the stern and remained motionless. Attempts to take it in tow failed.  Air defense of tanker was weak.  Around 1730 English surface units came into view.  Da Mosto immediately went into the attack and achieved hits on a cruiser.[1]  After a short time Da Mosto was hit in the stern.  Ammunition and the Italian depth charges went off.  During the sinking the forward torpedoes were fired, but without a hit. Da Mosto sank around 1800. The crew gave cheers to its ship, the Duce and the Führer.  The English destroyers drove through the swimming crew without attempting to rescue someone, and shouted derisively “Good bye boys”.

Petty Officer Rublack swam to the tanker with two Italians to bring a still intact boat into the water and to sink the tanker. A destroyer opened fire however, so that the intent could not be carried out.  The tanker then also sank soon afterwards.  Another destroyer appears to have had the intent before that to take it into tow[2].

The S-Geraet was kept manned until the start of the engagement when the boat went to high speed.  The listening crews thereafter went to their battle stations on the guns.  Petty Officer Rublack and Ordinary Seaman Maidenoff were on the bridge. Able Seaman Macher fell at the rear gun.  Nothing has been observed concerning the whereabouts of Able Seaman Hartmann and Ordinary Seaman Retter, who until the last moment manned the S-Geraet.

Around 2300 the torpedo boat Prestinari reached the site of the engagement and took the survivors on board.

The commander, Fregattenkapitaen (Commander) del Anno was very complimentary about the performance and the brave behaviour of the German listening crew. Petty Officer Rublack received the Iron Cross 2nd Class and the Italian Bronze Medal of Valour, and Ordinary Seaman Maidenoff the Iron Cross 2nd Class and the Italian War Merit Cross. The commander received the Gold Medal (later killed in action as commander of Scirocco).

RCT Da Mosto USMM

Alvise da Mosto underway in the 1930s. The picture shows the unusual configuration of the B-turret very well. USMM via Wikipedia.

Notes

[1]This is not correct.

[2]This is wrong.

Further Reading
A very informative article on the anti-submarine warfare development of the Kriegsmarine can be found at this link (search the document for “magnetostrictive” to jump directly to the ASW section).

A very informative, but highly technical, article on German passive sonar can be found at this link.