Marauders of the Sea, German Armed Merchant Ships During W.W. 2

Thor, First Cruise

Thor (Ship 10)
"Thor" of only 3,144 tons built in 1938 in Hamburg, had commissioned as the Banana ship, "Santa Cruz." When compared with the usual merchant ship, any vessel designed as a fruit carrier was faster. Because of the deterioration factor of the cargo carried, it was rnandatory to quickly move the fruit across the seas to a waiting market; any delays were liable to cause loss of both cargo and profit. These ships also were usually smaller. For a Raider, the presentation of a small silhouete to an enemy ship was a distinct advantage, thus, "Thor," was one of the smaller ships to convert to a Raider role.


This ship had a design speed of 17 knots, to be produced from oil fired steam turbines, and at the economical speed of 10 knots, was blessedwith a 40,000 miles cruising capacity. Her main armament was the usual Raider 6 by 5.9 inch guns. plus a 60mm poop gun, carried for defence by most Allied Merchantmen. Four torpedo tubes were fitted, 2 by 37mm weapons, and 4 by 20mm AA guns completed the offensive armament. Finally, an Arado aircraft was onboard for scouting purposes.

Otto Kahler was appointed in command in Octoler 1939. He was then 45, and had been a Naval Officer since 1914. "Thor" sailed on the 6th of June in 1940 out of Kiel, posIng as the Russian steamship "Orsk" and managed to slip into the Atlantic assisted by low visibility due to fog and snow.

By the 23rd of June this new raider was South West of the Azores, having avoided four likely enemy ships, as she was making for her South Atlantic sphere of opetations and did not want to alert prying eyes to her intended role; disguise was again changed, now becoming the Yugoslav "Vir" from Split, and sailing ex Liverpool to Pernambuco and Santos.

When nominating to be a specific ship it was always necessary to have a plausible reason to be sailing in that section of the world's oceans, and the Raider needed to be of a similar tonnage and appearance as her real namesake.

"Thor" was in business on the 1st of July 1940, she quickly found and stopped the Dutch "Kertosono," a single warning shot had done the trick. This vessel of 9,289 tons was loaded with asphalt, timber, petrol, plus agricultural machinery, She had sailed from New Orleans then on to Curacao and Freetown in West Africa and was destined for British ports. A crew of 56 were aboard, plus 9 passengers includitig 4 women, one of whom had a baby. Kahler was loath to scuttle this shp, and put a prize crew onboard, giving them instructions to sail her to Lorient, and his orders were achieved in 12 days.

In another week, a second ship was sighted just below the eequator, it was chased and stopped after firing a full broadside at a range of 8,000 yards. This victim proved to be the British "Delambre," just over 7,000 tons. full of cotton, hides and cotton seed from South America and bound for Liverpool. She carried an English crew of 44, plus a passenger.

I can't imagine why cotton seed would be shipped to Britain in 1940, the country needed immense quantities of food to survive, but perhaps this commodity was meant to be trans-shipped to assist Russian agriculture, another of the unsolved mysteries of the war.

All of the 45 people were taken aboard "Thor," and "Delambre," and scuttled. Her Captain indicating he had suffered the same indignity during WW1, when captured by the "Mowe."

'"Thor" remained busy; on the 9th. the Belgian "Bruges," who happened to have been a former 5,000 ton German ship captured in 1914, now carrying 6,746 tons of wheat, was stopped and scuttled, yielding a further 44 prisoners. Then in another 5 days, the "Gracefield," a British ship, was stopped off Trinidad. She also had holds bulging with wheat and bran, and was sailing for London. The crew of 36 all joined those previously captured in "Thor," and 2 torpedoes were fired, one ran erratically round in circles, and the Captain needed to use gunfire to finally despatch this ship.


On the 16th of July, the "Wendover," loaded with 7,250 tons of coal was fired upon without the customary order to "stop your ship," she was set on fire, abandoned, and a "Thor" boarding party set off demolition charges. She subsequently turned turtle, then floated. 5.9 inch shells were needed to sink her. Four of the 40 crew members died as a result of this action.

The next day the Dutch "Tele," of 3,777 tons and carrying 5,451 tons of grain for Britain was overtaken and sunk. All 33 of her crew were transferred to "Thor."

In the short space of but 17 days "Thor" had struck, and sunk, 6 ships making up a total of 32, 501 tons, and had or board 194 prisoners. "The little ship is beginning to get crowded."

Three of the vessels sunk had been carrying grain no doubt desperately needed in the United Kingdom. "Thor" was indeed making her presence felt in her role of harrassing Allied commerce, and removing from the scene trained Merchant seamen.

On the fine clear morning of the 28th. of July, at a distance of 14 nautical miles, a large ship was sighted. It could be a cargo ship steaming at 6 knots, or, more ominously, an enemy Armed Merchant Cruiser. "Thor" went to action stations, increased speed to 17 knots, and altered course to investigate. She now turned to the South West, to be immediately followed by the ship in view. Kahler was convinced he had met a British Armed Merchant Cruiser.

He carried in his general orders, a segment indicating that he should always try to avoid any confrontation with an enemy Warship. He thus turned away seeking to escape at maximum speed but the British ship followed at a distance of about 10 miles. and chased them for another 2 hours. It was the "Alcantara," formerly a 22,000 tons plus Royal Mail liner. She proved to be the faster ship, and began to close the gap.

If he was to survive and escape, Kahler believed that he must damage the "Alcantara" by gun fire to slow her down.

Just before 1300 (1PM) "Thor" showed her true identity, and reduced speed to I5 knots; at top speed, heavy vibration made it impossible for both the gun layers and range finder personnel to work accurately. "Thor" turned across the bows of "Alcantara" and at a range of 7 miles let loose a 4 gun broadside.

The Armed Merchant Cruiser immediately responded with return gun fire but the German Raider scored 3 hits, one in the engine room which promptly slowed down her opponent A British shell passed right through "Thor" without exploding, then splinters from a second hit wounded 4, killed 3, and put the starboard torpedo tubes out of action on a temporary basis.

"Alcantara" stopped and Kahler pondered whether to close her and deliver the "coup de grace," but decided that discretion was the better option. "To break off the the engagement and live to continue his mission appeared the action to take. It would he a tragic end to be sunk by a lucky shot from the British ship. Nonetheless Kahler had fired 284 of his outfit of 5.9 inch shells.


Under cover of"Alcantara's" smoke, "Thor," at 1335 (1.3 5PM) steamed away, and then her crew worked upon changing her appearance.

"Alcantara" survived and steamed back to her base, it needed a collision mat fitted over her side to stop the ocean rushing in, whilst 2 feet of water slopped around above the top of her tanks.

By the end of July, "Thor" was in the latitude of Cape Town, she slowed down to 5 knots, spending 12 days boiler cleaning, and making repairs to the battle damage.

The ship was to meet "Rekem" as arranged by Berlin, to get rid of the prisoners, and replenish, but when they finally made the rendezvous this tanker was unable to accept the prisoners.

The 12th. of September, found "Thor" well East of Pernambuco, and they cruised to the northward for another 2 weeks, then came across a whaling factory ship- the Norwegian "Kosmos," she was a large vessel over 17,000 tons, with a full load of whale oil, a crew of 89, and bound for Curacao.

Kahler would have liked to get such a prize with this very valuable cargo of oil home to a French port now in German hands, but in his judgement, a number of factors mitigated against such action. "Kosmos" was short of fuel, she was a slow ship, it would be hard to disguise her, she had 2 very distinctive funnels, side by side, close to her stern. He sank this ship, to be later roundly criticised by his control in Berlin, for not trying to get such a valuable ship and cargo home.

British ship "Willesden"

British ship "Willesden"

Another boiler clean was carried out, as "Thor" wallowed in the mid Atlantic swell just North of the equator over the next 12 days.

On the 8th. of October, a ship was sighted enroute to America from Europe. "Thor" opened fire to immediately score a direct hit, but this did not prevent their quarry using her radio, gunfire continued, and the alarm radio signals jammed. 175 rounds were fired to score 4 hits, then a torpedo rushed to the target and hit, but still the "Natia" did not succumb, another 35 shells were required to finally sink her.

This ship, a British refrigerated freighter of 8,715 tons was on her way to Buenos Aires, one presumes to load meat for the return trip to Britain. She carried a large crew of 85, one of whom was killed, and another wounded by the gunfire.

"Thor" crammed these survivors onboard, to now carry a total of 368 prisoners.

"Rio Grande" now met "Thor," who at long last was able to divest herself of the burden of all the prisoners, one can imagine the sigh of relief now uttered by "Thor's" Captain, as once again he was relieved of this problem of feeding, housing and guarding them.

"Thor" now shaped a course for the River Plate/Capetown shipping route, being warned from home that between the Cape of Good Hope and Freetown in West Africa there were 8 enemy Cruisers operating, whilst a further 2 were off the South American East coast.

Early in December, at 0531 (5.31 AM), out of the fog loomed a large steamship, but four miles away.


It was quickiy identified as an Armed Merchant cruiser, probably the "Carnarvon Castle." Kahler had hoped to elude this enemy ship by sneaking away in the fog. He rang up full speed from the bridge, and called the crew to "action stations."

He began to put distance between himself and the A.M.C. but now the enemy had worked up speed and was starting to catch him, and at 0701(7.01 AM) opened fire, "Thor" returned fire, and 2 torpedoes were also fired, but they both missed their target.

The German Raider was now firing salvoes quite rapidly, and scored 5 hits. After an hour's action, "Carnarvon Castle" turned to the North, and made off at reduced speed, having failed to score a single hit on "Thor." In fact the British ship had suffered about 40% casualities to her exposed crew members. Another victory for Kahler, his ship, and her ship's company.

The British A.M.C. made for Montevideo to undertake emergency repairs, patches to her hull used steel plates from the wreck of "Admiral Graf Spee," scuttled in December of 1939.

A few days short of Christmas, Kahler kept a rendezvous with 5 friendly ships including the pocket battleship "Scheer." Some thought was given to working in concert with "Scheer" - but Kahler avoided that proposition. It was resolved that "Scheer" would operate North of the 30th. parallel of latitude, and "Thor" would stay South of it.

One of the 5 ships met was the "Duquesa," which had been captured by the "Scheer" - she was used as a floating store. When seized, she carried 3,500 tons of frozen meat, and an incredible 15 million eggs. If brought to action, what a huge amount of scrambled eggs that would have provided!!

As she had exhausted her fuel, it was the task of the 'Nordmark" to tow her around the South Atlantic, to provide sustenence to the roaming German ships, eventually after supplying another Raider, the "Pinguin," she was then scuttled. New Year's day 1941 dawned, and the whole of this month passed without any sightings or action. From the 14th. of February for 2 weeks, supplies, torpedoes, 1000 rounds of 5.9 inch shells were ferried on board from 2 supply ships, a heavy swell making these transfers a hazardous operation.

March was uneventful until the 25th. when on the horizon a cloud of smoke came into view, it was to become the British "Britannia" of 8,799 tons with a passenger list of 300, and a crew of 200. Gunfire forced the abandonment of this ship, and 500 souls took to the ship's boats. Once they had pulled clear, Kahler then proceeded to systematically sink her, scoring 16 hits on her waterline.

Sierra Leone radio station reported that a British Cruiser, 100 miles away was hastening to the rescue, so Kahler left this assembly in their open boats and quickly steamed away.

The same day in the afternoon watch, "Thor" stopped a Swedish ship - "Trolleholm" of just over 5,000 tons. She was under charter to the British Admiralty and carrying coal from England to Port Said. Her crew were removed, and she was quickly sunk using demolition charges.


Just after dawn on the 4th. of April, the bridge watch sighted a coal burning ship, the range was closed quickly as the two ships were steaming on opposite courses, hauling down the Greek flag he was wearing~ and replacing it with the German flag, Kahler fired a shot across the bows of the oncoming vessel.

He was suddenly aware of 2 guns fitted in the fore part of this ship, then quickly came the realisation that he was engaging a British Armed Merchant Cruiser, this time the "Voltaire" of 13,245 tons.

The first salvo from "Thor" struck home, and within 3 minutes "Voltaire" was heavily on fire amidships, by 0715 (7.1 5AM) it was apparent that the enemy ship had steering gear problems, steaming around in circles. "Voltaire" sank at 0835 (8.3 5AM) and "Thor' stayed in the vicinity until 1300 (1PM )- to pick up survivors, 197 including their Captain and 19 officers, she then sailed off to the North.

"Thor" fuelled from the tanker "Ill" over the 12th. and 13th. of April, transferring 170 of her prisoners. It was time to make for home. This Raider made her last capture, the Swedish "Sir Ernest Cassel" of 7,739 tons- she was in ballast, and after taking onboard all her crew, she was scuttled.

By the 23rd. of April, Kahler was off France, and being escorted by 2 Destroyers and 3 Aircraft, up the Channel via Cherbourg, Le Havre and the Hook, steaming only at night.

By the month's end they were safe in Hamburg, after 329 days at sea, having steamed 57,532 miles, sunk 12 ships for a total of 76, 547 tons.

Kahler was a resourceful and efficient Raider Captain who had been most successful in his mission to harry and destroy Allied ships, including surviving 3 actions against British Armed Merchant Cruisers. In each of these actions he had proved superior, sinking one ship, and damaging the other two, whilst keeping his ship intact, although being damaged on one occasion.

He eventually headed up the Department for Merchant Shipping, and in February 1944 made Rear Admiral, then was appointed Naval Officer in Charge Brittany- however, after the Allied landings he was captured by Americans, and transported to the United States as a Prisoner of War.

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