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Warship Wednesday 30 September 2026: What Friends Are For

Here at LSOZI, we take a break every Wednesday to explore the old steam/diesel navies from 1833 to 1954, profiling a different ship each week. These ships have a life, a tale all their own, which sometimes takes them to the strangest places.- Christopher Eger 

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Warship Wednesday 30 September 2026: What Friends Are For

NIMH photo, via the Fotoafdrukken Koninklijke Marine, No. 2158_002974

Above, we see the Free Dutch Gerard Callenburgh-class destroyer (torpedobootjager) Hr.Ms. Isaac Sweers (G 83) steaming into the Grand Harbor of Malta circa late 1942, wearing British Atlantic camo.

Some 85 years ago this week, Sweers was part of the epic Operation Halberd, a resupply operation to keep besieged Malta fed, and lent her advanced AAA guns to help swat down Axis torpedo bombers.

All in a day’s work.

Dutch destroyer primer

A fleet based on cruisers, gunboats, and torpedo boats, the Netherlands dipped their first toe in the water of destroyerdom in 1909 with a group of eight Roofdier (Wolf)-class tin cans, the first serial-built Dutch turbine-engine ships, built for service in the East Indies. Small, 510-ton, 229-foot ships with four 3-inch guns and two torpedo tubes, they could make 30 knots on their combination of Krupp-Germania steam turbines and English Yarrow boilers.

The Torpedobootjager Hr. Ms. Fret (Ferret), of the first Dutch destroyer class, was in commission from 1911 to 1922, then used as a target ship until 1930. All of her sisters were named after predators (Roofdiers). Note the canvas sea bridge and knifelike 21-foot beam. NIMH 2158_002538

With the eight obsolete Roofdiers stricken by the 1920s, they were replaced hull-for-hull with a batch of eight 30-knot Admiralen-type tin cans built on a Yarrow design starting in 1925, based on the construction of the British destroyer Ambuscade. Built in two batches, the Van Ghents and the Van Galens, they were the same general size (1,640 tons/322-feet) and batteries (4×4.7-inch guns, 6 torpedo tubes); they differed in range. Plus, interestingly, they had weight and space for a seaplane.

The Dutch Admiralen types, via the 1938 Jane’s:

Then, by the mid-1930s, with both the Germans beating the war drums in Europe and the Japanese doing the same in the Pacific with an eye towards the Dutch East Indies, it was decided to replace the fleet’s 12 mis-matched and aging T-class (Thornycroft), Z-class (Schelde), and G-class (Fljenoord) torpedo boats– most dating to the Great War, armed with just a deck gun or two and a few 17.7-inch tubes and struggling to make 25 knots– with a dozen much larger and more capable destroyers, outclassing even the Admiralens.

Dutch Callenburg-class destroyers, Janes 1938

This expansion came as part of Vlootplan Deckers, the Deckers Fleet Plan, named after Minister of the Navy, Dr. L.N. Deckers. The plan was to replace aging assets with modern ones and envisioned three light cruisers, another pair of “torpedokruisers” (torpedo/scout cruisers) to serve as flotilla leaders for the 20 modern destroyers (eight Admiralen and 12 Callenburghs), and at least 26 submarines (eight in Europe and 18 in the Dutch East Indies) augmented by 90 land-based Dornier Do 24K three-engine patrol bombers of the Marine-Luchtvaartdienst (MLD). Added to this were new gunnery training ships and gunboats to serve ancillary wartime duties. By 1938, this ambitious plan was even augmented by a new push (Project 1047) to build a trio of hulking 25,000-ton Scharnhorst-style “cruiser killers” with 11-inch guns and swathed in 9 inches of armor, envisioned to begin to join the fleet in 1944.

Moving past the Deckers Plan, let’s just focus on the Callenburghs.

With an overall length of 349 feet and a 35-foot beam, they had a natural 1:10 ratio and could float in just over 10 feet of seawater. Light displacement was 1,628 tons, full 2,240. This made them roughly the same size as the British Tribal-class destroyers.

The Dutch machine factory Werkspoor obtained licenses for Parsons geared steam turbines and Yarrow 3-drum boilers intended to equip the newest fleet of destroyers. Using a powerplant of three oil-fired boilers and twin turbines on twin screws, they could generate 45,000 shp at 475rpm for a designed speed of 36 knots. Of note, the class leader hit 50,100 shp on speed trials at full load by superheating the boilers to 350 °C, reaching 515 rpm and 42 knots. Twin in-line fire rooms and stacks provided redundancy against damage. Range on 560 tons of oil was 5,400nm at 19 knots, which was superior to the 5,700nm @ 15 kts of Tribals.

The intended armament was to be a main battery of five 4.7″/45 Bofors-derived Wilton-Fijenoord guns in two No. 8 twin mounts (one fore, one aft) and one single No. 6 mount amidships between the two stacks.

Built under license from Bofors by the ordnance office of the Wilton-Feijenoord Dockyard in Rotterdam, the Dutch before the war produced 17 4.7″/45s for the ships in armored turrets, and another 22 to equip six coastal batteries along the coast of the Netherlands. Capable of firing 10-12 rounds per minute at 19,500m, the electrically powered turrets were armored to 60mm.

Gerard Callenburgh-class destroyer initial 1937 general plan and longitudinal section, showing the original planned stern Fokker platform. Note the gun and torpedo arrangement. Nationaal Archief

Her secondary battery included two twin 40mm/56 Bofors No. 3 AAA guns (one over each twin 4.7″/45 mount) with Hazemayer fire control systems (more on this later) and two twin water-cooled .50 cal Colt (Browning) export Model 1924 mounts (on each side of the bridge wings), the latter platform also used on Dutch Flores-class sloops, minesweepers, and the minelayer Bloemendaal. The Dutch were also trialing the twin air-cooled Swiss-made Solothurn S-14-200 .50 cals with Zeiss sights, which were installed on the one-off frigate Johan Maurits van Nassau.

Twin Colt Model 1924 watercooled 50 cal Browning on a Dutch minesweeper, 1940s 2158_015801

They had eight 21-inch torpedo tubes (lancerbuizen) in two quad turnstiles serviced by a torpedo davit on each side of the deck. Two spare torps could be carried in a magazine behind the first turnstile, giving the destroyers a capacity of 10 fish in all.

Maintenance on the torpedoes aboard the destroyer Hr. Ms. Isaac Sweers, circa 1941-42. NIMH 2158_002975

Anti-submarine weapons consisted of four depth charge throwers (dieptebombenwerpers) with space for a dozen cans.

They also had space for 24 sea mines on deck in place of stern depth charge rails and mechanical minesweeping gear in the form of two paravanes and chains, stored by the ship’s boats, which included a 23-foot motor launch and a 26-foot eight-oared rowing sloop with an auxiliary motor (Sloep B IV met hulpmotor).

Like the Admiralen-classes, these new destroyers would be capable of carrying a crane-launched and recovered single-engine seaplane, typically a Dutch-made Fokker C.VII-W.

The plane was initially going to be stowed to the aft with its tail hanging over the stern 40mm mount when stocked, but this shifted amidships with the single 4.7″/45 No. 6 single mount shifted aft instead, overlooking the stern 4.7″/45 twin No. 8, in the position of the stern 40mm twin mount which instead was moved to a bandstand between the two torpedo tube turnstile. The two twin .50-cal water-cooled Colt-Brownings were likewise moved from the bridge wing to flank the second funnel, abeam, port and starboard.

Gerard Callenburgh-class destroyer plan, showing the planned amidships Fokker platform and the reallocated guns. Nationaal Archief NL 4.MST_1921

Gerard Callenburgh-class destroyer finalized rigging plan, showing the planned amidships Fokker platform and the reallocated guns. Nationaal Archief

A Fokker C.VII-W seaplane on the Admiralen-class destroyer Hr.Ms. Witte de With at anchor, Koepang, Timor, Dutch East Indies, September 1934.  NIMH 2173-223-014

The Dutch were the only users of the Fokker C.VII-W, buying 30 of them for the MLD. Capable of a 70 kt cruising speed and 600nm range, these open cockpit canvas beauties could carry two light bombs and a twin observer-manned Vickers gun on a ring mount.

They were designed for a peacetime complement of 158: 11 officers, 19 NCOs, and 128 enlisted, growing to over 200 in wartime.

As they were built for service in the Dutch East Indies, it was likely that as much as a quarter of their enlisted would be drawn from Indonesian volunteers. In 1933, the Dutch Navy had about 12,000 officers and men, including around 2,500 indigenous sailors drawn from the DEI, with efforts to train local officer candidates underway in 1940.

The first two members of the class, Callenburgh (Yard No. 208) and Tjerk Hiddes (Yard 207), were laid down six weeks apart at RDM in Rotterdam and constructed side by side.

Construction of -right- the Tjerk Hiddes and -left- the Gerard Callenburgh at the Rotterdamsche Droogdok Maatschappij, 9 June 1939. Note the RDM yard numbers on each hull. NIMH 2158_012320

Construction of -right- the Tjerk Hiddes and -left- the Gerard Callenburgh at the Rotterdamsche Droogdok Maatschappij, 13 September 1939. Note the RDM yard numbers on each hull.  NIMH 2158_031833

They were both christened by Mrs. G. A. J. Dijxhoorn-Ybes, the wife of the Minister of Defense.

The next two of the class, our Isaac Sweers and sister Philips van Almonde, were ordered from Koninklijke Mij De Schelde, Flushing.

In Dutch fashion, all were to have name initials as pennant numbers (Gerard Callenburgh was GC, Tjerk Hiddes TH, Isaac Sweers IS, Philips van Almonde PA)

This all brings us to…

Meet Sweers

Our subject is named in honor of Isaak Sweers (also seen as Ysaack Sweerts), Vice-Admiraal van Holland en West-Friesland, a 17th-century naval hero of the Anglo-Dutch wars. Sweers was a swashbuckler who first saw combat in his 20s under Jan van Galen against the Barbary Pirates and later sailed on Michiel de Ruyter’s expedition to West Africa and America. He was killed in a North Sea naval battle via a direct hit from a British 24-pounder cannonball that saved only his torso for the coffin– but left the Dutch with a victory.

Sweers and the painting by Willem van de Velde the Younger, “Night Battle between Tromp and Spragge at Kijkduin,” August 21, 1673; the 227-ship naval battle in which Sweers was mortally wounded, at age 51. Both via the Nationaal Archief

Laid down on 26 November 1938 at Koninklijke Mij De Schelde, Vlissingen, Zeeland, she was Yard No. 212 while her sister, the planned Philips van Almonde, was laid down four months later as Yard No. 213.

March 1939. The future Isaac Sweers on the builder’s ways on Kon. Mij. De Schelde te Vlissingen. NIMH 2158_002965

The future Isaac Sweers was christened by sponsor (doopster) Mrs. Johanna van den Arend-Keers, wife of LtZ Henry van den Arend, supervisor of the destroyers under construction at the yard. 16 March 1940

The future Torpedobootjager Hr. Ms. Isaac Sweers was launched at Vlissingen, 16 March 1940. NIMH 2158_028945

Torpedobootjager Hr.Ms. Isaac Sweers gereed voor de tewaterlating bij de Kon. Mij. De Schelde te Vlissingen, 16 March 1940. NIMH

Sliding down the ways, 16 March 1940. NIMH 2158_002967

Hr.Ms. Isaac Sweers in Schelde te Vlissingen being fitted out, between April and May 1940. NIMH 2158_028947

Same as the above. NIMH 2158_028946

30 April 1940, the submarine Hr.Ms. O 22 (K XXII) comes back home to Vlissingen following sea trials, passing the fitting out Isaac Sweers. For reference, O 22 escaped incomplete to England when the Germans occupied Holland the next month and went missing off Norway on her fifth war patrol. NIMH 2158_015482

War!

During the first eight and a half months of WWII, although the country was neutral, the Dutch merchant marine was very much at war, with 43 merchant ships lost or severely damaged due to acts of war– and that isn’t even counting the fishing fleet, which also suffered heavy losses.

When the Germans swept into the neutral Netherlands as part of their sweep through the Lowlands on 10 May 1940, the Dutch had no hopes of stopping the 29 battle-hardened enemy divisions of Von Bock’s Armee Group B with their nine much lighter divisions– especially with an army that had not seen combat in Europe since 1831. Plus, the Germans had something like a 7:1 local advantage in tactical aircraft, allowing the Luftwaffe to largely control the skies on Day 1.

Most of the Dutch fleet at the time was deployed to the Far East to oppose an increasingly warlike Japan. This included the cruisers De Ruyter, Java, and Tromp, all of the active Admiralen-class destroyers, 15 submarines, and a myriad of smaller craft, as well as the bulk of the MLD’s combat aircraft– including 37 new Dornier Do 24 K-1 flying boats, soon augmented by 36 PBY Catalinas. Their inferno along the Java Sea would come at the hands of the Emperor’s Combined Fleet in 1942.

Left in Europe was the old 8,000-ton cruiser Hr.Ms. Sumatra, awaiting her mid-life refit in Vlissingen; the new cruiser Jacob van Heemskerck, still fitting out; the four building Gerard Callenburgh-class destroyers; assorted auxiliaries; and 13 submarines, most of which were either under construction or in dry dock for refit. The commander of the Royal Dutch Navy, VADM Johannes Furstner, soon left the country with Queen Wilhelmina and family on Sumatra for England to continue the fight, and issued orders for the rest of the fleet to do the same.

The Admiralen-class destroyer Van Galen, in refit at Rotterdam, was bombed and damaged by Heinkel He 111 aircraft of Kampfgeschwader 4 on 10 May and sank in the Merwedehaven. The same day, the tug De Oceaan, too slow to make a getaway, was scuttled as a block ship.

The 11th saw the old gunboat Braga scuttled in the Waal, while the Luftwaffe sank the Dutch liners Statendam and Veendam, along with the steamer Stella.

The 12th saw the gunboats Bulgia and Friso and the hospital ship Luctor et Emergo sunk by German bombs, joined by the steamers Prinses Juliana and Van Rensselaer.

On the 13th, the torpedo boat Christiaan Cornelis was scuttled by her crew after sustaining crippling battle damage, while the minesweeper M 2 was sunk while doing her job.

The 14th was a day of reckoning for the Dutch Navy. Destroyed by the Germans or scuttled by their crew were the ancient and immobile 5,000-ton coastal battleship Batterijschip IJmuiden, the brave sloop/frigate Johan Maurits van Nassau, the yard-bound submarines O 8, O 11, O 12, O 25, O 26, and O 27; the minesweepers Abraham van der Hulst, M 1, M 3, M 4, and Pieter Florisz, the minelayer Hydra, the gunboats Brinio, Freyr, Hefring, and Tyr; the torpedo boats Jan Danielzoon van de Rijn, G 16, and Z 3; the tug Noordzee II, and the merchant steamers Jan Pieterszoon Coen and Naaldwijk.

Picture postcard with drawings of some of the Dutch warships lost during the May days of 1940. Top left: the gunboat Hr.Ms. Johan Maurits van Nassau (1933-1940), which was sunk by aerial bombs on May 14, 1940, between Petten and Callantsoog. Top right: the torpedo boat Hr.Ms. Z 3 (1920-1940), which was sunk by its own crew near Enkhuizen on May 14, 1940. Below that: the destroyer Hr.Ms. Van Galen (1929-1940), which was sunk by aerial bombs near Rotterdam on May 10, 1940. Below that, on the left: the minelayer Hr.Ms. Hydra (1912-1940), which was heavily damaged by German anti-tank fire in the Zijpe near St. Philipsstad on May 15, 1940, and grounded in shallow water. Next to it on the right are the minesweepers Hr. Ms. Pieter Florisz (1937-1940) and Hr. Ms. Abraham van der Hulst (1937-1940), which was sunk by its own crew near Medemblik and Enkhuizen on May 14. Below that on the left is the accommodation ship in Vlissingen, Hr.Ms. Noordbrabant (1925-1940) was set on fire by its own crew on May 17, 1940. Next to it is the gunboat Hr. Ms. Friso (1915-1940), which was heavily damaged by aircraft bombs on the IJsselmeer on May 12, 1940, and subsequently by gunfire from Hr. Ms. Pieter Florisz (1937-194) was sunk after the crew had abandoned the ship. Additionally, the gunboat Hr. Ms. Brinio (1914-1940), which was sunk by its own crew on Lake IJssel near Enkhuizen on May 14, 1940. Additionally, the minelayer Zr./Hr.Ms. Bulgia (1894-1940), which was sunk during an air raid on Vlissingen on May 12. NIMH 2061-006-001

Looking to fight another day, the cruisers Sumatra and Jacob van Heemskerck, the gunboat Gruno, the minelayers Jan van Gelder and Willem van der Zaan, and seven Dutch submarines (O 9, O 10, O 13, O 21, O 22, O 23, and O 24) escaped from the European mainland to Great Britain, most under strafing attacks by German fighters and a hail of German bombs. Heemskerck had to be towed, and the O 20-series subs were at various stages of incompleteness.

They were joined by an armada of coasters and merchant vessels that also ran the gauntlet. No less than 39 Dutch coasters took part in the “Miracle from Dunkirk” and the Channel harbors of France over the next month, lifting at least 1,900 Dutch troops away from the maelstrom. In all, more than 1,200 Dutch merchant ships would serve with the Allies during WWII, with estimates hovering at about 525 of those lost.

The Dutch army units, which had not yet linked up with the Allies, laid down their arms on the morning of 15 May.

Dutch RADM Hoyte Jolles, commanding nearly 10,000 stranded sailors, marines, shipyard workers, and recalled reservists at Den Helder, which included several fortified coastal defense sites, wanted to keep fighting until the bitter end and was only narrowly convinced by CiC Gen. Henri Winkelman not to waste his men’s lives.

But what of our four building destroyers?

On the Issac Sweers, MLD LtZ Baron Hugo Anne Victor Raoul van Lawick gathered 10 naval personnel and six shipyard workers, all volunteers, and, with the blessing of KMDS personnel, cast off the incomplete destroyer on the late evening of 10 May 1940.

Using the requisitioned 850-ton L. Smit & Co tugboat Zwarte Zee (Black Sea), the shoestring operation managed to tow the hull 80 miles from Vlissingen to The Downs in England– dodging four German magnetic mines dropped in the path of the tug– where they arrived on the late morning of the 11th. Safe, they moved to Spithead the following day.

There, Sweers was tied up, safe from the German advance. Zwarte Zee remained English waters, joining 12 other Dutch ocean-going tugs, and, despite being sunk at least once, entered the service of the British Admiralty as a salvage vessel and tow boat. Zwarte Zee’s master throughout the war, Teun Vet, was honored with the Dutch Bronze Lion (Bronzen Leeuw).

As for the building, Tjerk Hiddes and Gerard Callenburgh, still being fitted out in Rotterdam, were both scuttled on the Nieuwe Waterweg by naval and RDM personnel, putting them out of the Germans’ hands for at least the time being.

The fourth ship of the class, the building Philips van Almonde, still in the stocks as she was just laid down in March 1939, was blown up at the shipyard in Vlissingen and scrapped by the Germans.

Completion abroad

In June, Isaac Sweers was towed to Thornycroft shipyard at Southampton, where she would be completed, a process that took nearly a year.

Torpedobootjager Hr.Ms. Isaac Sweers in drydock at John I. Thornycroft & Co. Ltd., Southampton, October 1940. Note that her screws haven’t been installed yet. NIMH 2158_002969

Isaac Sweers in drydock at John I. Thornycroft. Note that her 40mm mount is covered, and the radar and fire-control system antennas have been marked out by the censor. Nationaal Archief 934-9828

While she had most of her intended equipment installed, including her propulsion plant, she did not have her main guns. This left her with three twin British 4″/45 QF Mk XVI mounts rather than the five 4.7″/45 Dutch guns she had planned. The incomplete cruiser Jacob van Heemskerck, likewise without guns, received five of the same mounts.

At Alexandria on the Free Dutch destroyer Issac Sweers (G 83). Dutch sailors off duty, enjoying a yarn beside depth-charges. Note the 4″/45 QF Mk XVI twin mount, 24 December 1941. By LT E.A. Zimmerman, RN. IWM (A 7263)

She also got two Vickers quad .50 cal mounts instead of the planned Colt-Browning twin .50s and British torpedo tubes, but never did get that seaplane fitted. Instead of the Dutch listening gear she had planned, she got a British Type 124 sonar.

Quad .50 cal Vickers mount on Isaac Sweers, at Alexandria, Egypt, 24 December 1941. By LT EA Zimmerman, IWM (A 7264)

Issac Sweers as completed, 1941, with British guns and radar. Dutch Nationaal Archief. 4.MST

Drawing by AD Baker III via British Destroyers from Earliest days to the Second World War by Friedman (Seaforth 2009).

The Brits were very interested in her 40mm Bofors mounts, as was its Hazemayer local fire control system, which was classified as the Range & Direction Finding system 289, or just called “The Dutch Device” by ASE Plymouth. Sea trials with the primitive radar showed that a Swordfish had a continuously trackable echo out to 4,400 yards, while barrage balloons could be pinged out to 6,600.

Hr.Ms. torpedobootjager Isaac Sweers at Vosper Tornycraft soon after completion. Note the barrage balloons overhead. NIMH 2158_005293

The electric listening device (RDF 289) transmitter-receiver on Isaac Sweers with the J-scope and headphones, shown next to an image of the RDF 289 transmitter section. Sweers had one of these sets in shacks behind each of her two 40mm Bofors mounts. 

The Brits elected to simplify the system for their own use and augment the Dutch ship with a range-only British UHF-band Type 282 fire control radar as well.

As noted by Friedman:

The Royal Navy was most impressed by the twin stabilized Bofors guns aboard Isaac Sweers and other Dutch warships. Both it and the U.S. Navy saw them demonstrated on board a Dutch gunboat in the West Indies. The U.S. reaction was to adopt a simplified (unstabilized) twin-powered Bofors in place of its quadruple 1.1-in anti-aircraft gun; this weapon entered widespread service from 1942 onwards. The Royal Navy was more interested in the mount, which it called a Hazemeyer, after the Dutch manufacturer (which later became Signaal), as a self-contained unit, carrying its own fire-control computer and its own range-only (Type 282) radar. A ship armed with multiple Hazemeyers could engage multiple air targets; a U.S. ship could engage only as many targets as she had off-mount directors (Mk 51 or radar-equipped successors such as Mk 57).

However, the complex mount turned out to be a manufacturing and maintenance nightmare, and the A through to I class destroyers could never be fitted with it. The promise of the Hazemeyer led the Royal Navy to develop the much heavier STAAG, with a next-generation radar (Type 262), and to project an even more elaborate Buster mounting, which would have weighed twenty tons (and was canceled).

The early 40mm Bofors Hazemeyer mount shown is aboard the destroyer Isaac Sweers, probably in mid-1941. The antennas are for the range-only British UHF-band Type 282 fire control radar. In effect, a Hazemeyer combined gun and fire control system, NIMH 2158_053881

A closer look at that Type 282. NIMH 2158_028955

With a 194-man crew drawn from across the assembled Free Dutch naval personnel in the West, Hr.Ms. Isaac Sweers, complete with the British pennant G 83 rather than her Dutch IS, entered service on 29 May 1941. Her first skipper was KtZ Jacques Houtsmuller, RNN, a regular who obtained his commission in 1916.

Hr.Ms. torpedobootjager Isaac Sweers (G 83) after completion in England. IWM (A 30815)

Finally, in the fight!

June 1941 saw Sweers in a series of trials off Portsmouth and Plymouth, during which she achieved a top speed of 36.7 knots over a measured mile. She continued her workups and exercises at Scapa Flow through July and on 1 August, arrived at Greenock to join the Western Approaches Command for escort duties.

She soon was part of the escort for Convoy WS 10, a slow “Winston Special” headed to Africa from the Clyde.

Then came WS 11, which she took as far as Gibraltar.

Our little Dutch destroyer, sailing with the 4th Destroyer Flotilla, became part of Admiral Somerville’s Operation Halberd at “The Rock,” bound for Malta. Running two convoys totaling 12 freighters packed with supplies for the island, Sweers fell in with 18 other destroyers (including two Poles), five cruisers, the battleships HMS Nelson, Rodney, and Prince of Wales, and the carrier Ark Royal. A force of nine Allied submarines (including the Dutch O 21) lined the way in patrols for the Italian fleet.

Speaking of which, the Italian RADM Angelo Iachino sortied out with two battlewagons, five cruisers, and 14 destroyers of his own, while the Italian air force had 500 assorted tactical aircraft based in Sardinia and Sicily that the Halberd force had to sail through.

When the smoke cleared, the Allied escorts and Ark Royal’s Fulmar’s shot down 21 attacking SM.79 and BR.20 torpedo bombers while only one Allied steamer (MV Imperial Star) was lost along the way. The Allied tin cans of Sweers’ 4th DF, specifically HMS Gurkha and Legion, sank the Italian sub Adua. Gurkha and Sweers also unsuccessfully chased the Italian submarine Diaspro.

Sweers had at least three “narrow misses” from Italian torpedoes in as many days, two sub-launched torps traveling too deep, and an air-dropped fish missing her bow by 30 meters. She also suffered two men injured from friendly fire splinters.

Arriving back in Gibraltar on 1 October, Sweers ventured out to help escort Convoy OS 9 to Freetown then came back north as an escort for Convoy SL 90

Back in Gibraltar for Operation Perpetual, one of the Club Run aircraft delivery missions to Malta, Sweers fell in with Force H– the carriers Argus and Ark Royal (the latter packed with Hurricane fighters and Blenheim bombers), battleship Malaya, cruiser Hermione, and six destroyers on 10 November.

Ordered from Gibraltar to Alexandria via Malta with fellow destroyers HMS Sikh, Legion, and Maori to reinforce the Mediterranean Fleet in December, on the early morning of 13 December near Cape Bon, Tunisia, the four greyhounds sighted ahead the outlines of two medium-sized ships steaming south. With the force commodore on Sikh (CDR Graham Stokes) warned about two Italian cruisers (Alberico da Barbiano and Alberto di Giussano) proceeding from Palermo to Tripoli thanks to Ultra intercepts, he immediately presumed them to be these ships, and soon the surface action was afoot.

Sikh, leading the column, went in first, torpedoes and guns opening up at 1,000 yards, followed by Legion and Maori, with 12 torps wrecking the Italian cruisers. Sweers, the last in the column, was able to get off 4-inch rounds at one of the burning cruisers (Alberto di Giussano) then switched fire an Italian torpedo boat (Cigno) running in close, obtaining several gun hits as the two traded missed torpedoes at close range in the dark. At the end of the scrap, the Allies suffered no casualties or damage, while both Italian cruisers were on the bottom, with 817 men from their crews. The damaged Cigno returned after dawn to pick up 500 waterlogged survivors.

The four Allied destroyers sailed into Alexandria with a hell of an after-action report on 19 December.

On Christmas Eve 1941, RN Photographer Lt. E.A. Zimmerman came aboard the Dutch man-of-war at Alexandria and captured her crew at work, then accompanied them for a Christmas ASW patrol.

Zimmerman’s photo essay:

CDR Houtsmuller, captain of the Isaac Sweers (left by one of the ship’s torpedo turnstiles) with RADM Irvine Gordon Glennie, Rear Admiral (Destroyers, Mediterranean Fleet). Glennie, who started the war commanding HMS Hood but had been kicked upstairs before she met Bismarck, retired as a full admiral in 1947, capping 42 years in uniform. By Zimmerman. IWM (A 7258)

At Alexandria on Issac Sweers. Dutch sailors pulling out torpedoes for cleaning, oiling, varnishing, and revision, 24 December 1941. By Zimmerman. IWM (A 7259)

At Alexandria on Issac Sweers. Dutch sailors pulling out torpedoes for cleaning, oiling, varnishing, and revision, 24 December 1941. By Zimmerman. IWM (A 7261)

At Alexandria on Issac Sweers. Members of the gun crew overhauling their pom-poms while in harbor. 24 December 1941. By Zimmerman. IWM (A 7264)

25 December 1941. ASW Patrol. Sending and receiving messages on the Dutch destroyer Isaac Sweers, while the look-out below scans the horizon. By Zimmerman IWM (A 8056)

25 December 1941. ASW Patrol, eastern Med. HMS Napier and HMS Nizam are almost hidden by bow waves from Isaac Sweers in heavy seas.  By Zimmerman IWM (A 8053)

In early 1942 at a ceremony at Admiralty House, a DSO (Houtsmuller), 2 DSCs, and 3 DSMs were presented by Admiral of the Fleet and First Sea Lord, Sir Dudley Pound, to officers of Isaac Sweers, “who participated in the night action in the Mediterranean on 13 December 1941 when two Italian cruisers and an E-boat were sunk and an Italian torpedo boat was heavily damaged.”

By this time, Houtsmuller had been replaced by KltZ Willem Harmsen, RNN, who had commanded the British loaned destroyer HNMS Campbeltown (I 42) throughout 1941. A regular, Harmsen had earned his first stripe in July 1915.

The new year saw Sweers on cross-Med Convoy ME 8, AT 12, and MW 8A/B. It was on the latter that U-133 (Kptlt Hesse) torpedoed Gurkha off Sidi Barrani on 17 January 1942. Sweers and Maori rushed to her aid and, after towing her out of a burning oil slick, Sweers picked up 240 survivors while Maori screened the rescue and hunted the attacker. Gurkha suffered nine losses.

Royal Navy L-class destroyer HMS Gurkha (G 65), one hour after being torpedoed by U-133 off Sidi Barrani on 17 January 1942. She would be on the bottom just 30 minutes later, with Sweers saving the majority of her crew. The photo was taken by D.J.Hoefsloot, the ship’s barber on Isaac Sweers.

On 29 January 1942, with a brand-new war being fought in the Pacific, Sweers was released from the Mediterranean Fleet and ordered to proceed to the Dutch East Indies to reinforce the Free Dutch forces there under pressure from the Japanese. However, upon arriving in Colombo via Port Said and Aden in late February, the situation in the Java Sea had come to a head, and there was no longer a Dutch fleet for Sweers to join in the Far East.

Falling in with the British Eastern Fleet in the Indian Ocean, she spent most of March and April escorting the battleship HMS Royal Sovereign, reacting to Operation C, the strong 5-carrier/4-battleship Japanese raid into the region.

Isaac Sweers in the Indian Ocean under British RN orders. Nationaal Archief NL 934-9831

Sweers, likely in a British port in 1942, looking worn. NIMH 2158 028954

After the Japanese retired back to the Pacific, Sweers was released to make her way to England via Durban, Simonstown, Freetown, and Gibraltar.

On 22 June 1942, she arrived at Thornycroft shipyard in Portsmouth for a much-needed refit after a solid year of high-tempo operations. She would remain there for three months. The refit saw Sweers land her quad Vickers .50s in exchange for four Oerlikon singles and pick up a British Western Approaches-style camo scheme.

Hr.Ms. torpedobootjager Isaac Sweers’ post-camo scheme late in her career. NIMH 2158_005303

After working up and exercises in Scapa Flow, Sweers was attached to the escort for troop Convoy KMF 1 for the Torch Landings in North Africa, and headed back to the Med in October. Once there, she was carved off on 5 November to join Force H, supporting the Eastern (Algiers) and Center (Oran) Task Forces.

On 11 November, Sweers and the British destroyer HMS Porcupine rescued 238 survivors from the Dutch troop transport Nieuw Zeeland, which had been torpedoed and sunk by U-380 about 80 miles east of Gibraltar.

The next day, our subject’s long streak of luck finally ran out.

At 0615  on 13 November, while northwest of Algiers, Sweers was hit by two torpedoes from U-431 (Kptlt Wilhelm Dommes) on the starboard side. One torpedo struck an oil tank, which had just been topped off by the fleet oiler HMS Dingledale, spreading burning oil over the ship and the water. The second torpedo hit the logroom and O quarters, killing all 13 officers sleeping there, with the butcher’s bill topping 108.

The 86 survivors were picked up by the British armed trawler HMS Loch Oskaig.

A snapshot of Hr. Ms. Isaac Sweers was found on the body of one of her crew after she was lost. The discolored spots are due to fuel oil, with which this survivor was also soaked. NIMH 2158_001537

For what it is worth, U-431 was chased to the ground the following October by RAF Wellingtons off Cartagena and sent to the bottom with all hands. Kptlt Dommes had, however, left the boat by then, sailing to the Pacific to become the Monsun Group commander at Penang, surviving the war with 11 patrols and 40,103 GRT to his credit.

Epilogue

Sweers‘ 1941 skipper of Cape Bon fame, KtZ Jacques Houtsmuller, RNN, survived the war and retired from the Navy in December 1946, capping a 30-year career and was made an Officer of the Order of Orange-Nassau. He passed away in 1974, aged 80.

Kapitein ter zee Jacques Houtsmuller, DSO, et, al

Her final skipper, KltZ Willem Harmsen, would go on to command the completed Jacob van Heemskerck in the Indian Ocean in 1943 and 44. He retired in 1946 as Commanding Officer, Naval Forces Rotterdam. He would pass in 1970, aged 77.

The Dutch naval aviator who managed to save the incomplete Isaac Sweers, Baron von Lawick, was killed in a plane crash in the Dutch East Indies in 1941, aged just 31. His only son, naturalist Baron Hugo van Lawick, married Jane Goodall and won eight Emmy Awards for his documentary films.

As for Zwarte Zee, the little tug that saved Isaac Sweers from the Germans in 1940, sailing as W 163, she and 11 other Dutch tugs would take part in Operation Pluto, the breakwater for Normandy, in 1944, when her sister Roode Zee was struck by a German torpedo and sunk with her entire crew. Returning home after the war, Zwarte Zee had a long career, chugging along for 33 years on her original pair of good old Werkspoor crosshead diesels.

On her last voyage to the scrappers in 1966, the old tug sailed slowly along the Nieuwe Maas through the port of Rotterdam, with many on the riverbank to bid farewell to the vessel.

Sleepboot Zwarte Zee waarschijnlijk in het Noordzeekanaal 1933

As for Issac Sweers’ sisters, the scuttled Gerard Callenburgh was salvaged and seized by the Germans in July 1940, then completed and served in the Kriegsmarine with a mixture of her Dutch main guns and German 20mm C/38 (16) and 37mm C/30 (4) flak guns and torpedo tubes, and as ZH1 (Zerstörer Holland 1), commissioned 11 October 1942.

Ex-Gerard Callenburgh, German ZH1, was sunk on 9 June 1944 by Allied destroyers (British HMS Tartar, Ashanti, Eskimo, and Javelin, the Canadian Haida and Huron, and the Polish Blyskawica) in the English Channel 10 miles NW of Ile de Bas by gunfire and torpedoes. NIMH 2158_035728

The scuttled Tjerk Hiddes, raised in June 1942, was planned to become ZH 2 but was never completed as such and was eventually scrapped at Hendrik-Ido-Ambacht.

An illustration of ZH 1 and 2 destroyers Source: “Die deutschen Kriegsschiffe 1815 – 1945, Band 2” book, by Erich Gröner

In a passive resistance kind of thing, the good patriotic employees of Werkspoor, under chief engineer Gerard Jan Lugt, duly disassembled and hid from the Germans eight Werkspoor-Parsons turbines meant for the Gerard Callenburgh class destroyers along with plans and machinery for their production, through a variety of subterfuges including offsite storage (including at the company’s vast railcar plant at Utrecht), disassembly, and burying them under scrap and rubbish piles until 1945.

Post-liberation, they were coupled with new Babcock boilers and recycled into the power plants of four new, albeit smaller and more modern, Type 47A (Holland) class submarine hunter (onderzeebootjager) ASW destroyers built in the early 1950s, sailing into the mid-1970s in Dutch service, with one later serving in Peru well into the 1980s.

The Type 47A Onderzeebootjager Hr.Ms. Holland, complete with a pair of quad Bofors 375mm ASW mortars forward of the bridge. She served from 1954 to 1977 with the Dutch, then until 1986 with Peru as BAP Garcia y Garcia (DD75)– and did it all with pre-WWII engines ordered for the Gerard Callenburgh class– and Holland broke 40 knots on builder’s sea trials! NIMH 2158_002863

Speaking of carrying a legacy forward, the Dutch reused the name of VADM Sweers for an NDSM-built Van Speijk (Dutch Leander)- class frigate (F 814), commissioned in 1968. She continued in service to the Koninklijke Marine until 1990, when she was decommissioned as part of a post-Cold War drawdown. Still young and in good condition, she was sold to Indonesia, where she remains in service as the Ahmad Yani-class frigate KRI Karel Satsuitubun (F 356), aged 58.

HNLMS Isaac Sweers (F814) during her Cold War service in the Royal Netherlands Navy. She continues to ply the Pacific under an Indonesian flag, serving alongside four of her sisters.

Thanks for reading!

Meminisse est ad Vivificandum – To Remember is to Keep Alive

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