As well as attacks against the enemy’s merchant shipping, the question of allocating Seehunds to the resupply of German defenders at Dunkirk – ‘Operation Kameraden’ – had been raised once more. This time Donitz agreed and the opening supply run departed Ijmuiden on 27 March, Frohnert and Beltrami the first of three crews assigned. The Seehund’s weaponry had been removed and replaced with two empty canisters of the same dimensions as a torpedo. These so-called ‘butter-torpedoes’ were loaded with the intended cargo, which comprised urgently-required foodstuffs such as a fat ration for each of the defenders as well as weaponry such as anti-tank mines and anti-tank artillery ammunition. Beltrami later recalled their voyage:
On 27 March we three supply Seehunds left Ijmuiden. We successfully travelled about two or three miles and made the obligatory trim test dive in salt water. But as soon as my tower hatch went under water I got a cold shower down the neck. We put the boat on the seabed to determine where the water was coming in and discovered two more places around the hatch that it was leaking from. I assumed that this was caused by damage that we had taken on an earlier mission when we were heavily depth charged by the enemy. The difficult mission that we had lined up ahead could not be accomplished with a boat unfit to dive. We decided that we had to return. When in the headquarters I reported to F.K. Brandi, complaining about the sloppy work done when repairing our boat.
The Seehund was worked on throughout the night and made ready to sail during the following afternoon. This time the test dive passed without problems and Frohnert and Beltrami were able to begin their mission proper. They headed into the teeth of a severe weather front that forced them underwater for hours as they waited for the storm to subside. Once surfaced they ironically had to creep past enemy shipping traffic – normally a target they longed to see.
We followed the coast and in the grey morning of the seventh day, we saw the silhouette of Ostend. There were many enemy ships in the harbour and we only had ‘butter torpedoes’ … We hugged the coast on to Dunkirk. There we were unable to enter the harbour as a minefield blocked our way forward. So we decided on a plan: I would climb out and signal with a hand torch to notify the posts on shore that we were there. It was still sea state 4! If I should fall overboard then the LI was to head south toward the beach. So I did what I said: clambered out, shut the hatch and held on to the periscope and signalled. The boat dipped a little so I was sometimes up to my waist in the water. In due course a signal came back from the head of the Mole: ‘Head 100 metres to the east, you are in a minefield! We will send a boat to guide you’. Open the hatch and back in the boat, the LI is very pleased. We head east…
Once docked in Dunkirk soldiers took the two crewmen to the hospital where they were given a warm bath while their boat was unloaded. The Fortress Kommandant, Admiral Frisius, made time to personally congratulate them, Heye doing likewise via radio. On 9 April they departed Dunkirk under a glowering sky. Their ‘torpedoes’ had been reloaded, this time with outgoing mail and messages from the trapped soldiers. Following a brief brush with a Mosquito fighter-bomber – bullets hammering the sea where the boat had just dived -and the almost obligatory motor and engine problems the Seehund entered Ijmuiden on 11 April. With the idea proven, the pattern of this successful mission was to be repeated until the end of the war.
By the beginning of April 1945 the Allied isolation of German-held regions within the Netherlands was nearly complete. The problems of supply for the K-Verbände had become critical and consideration was given to withdrawing the Biber and Linsen forces and rebasing them at Emden to defend the Ems waterway. This idea was deemed logisti-cally unworkable and rejected almost as quickly as it had been proposed, though further thought was given to moving Biber, Molch and Linsen units from Borkum to Emden instead. This too was judged impractical on transportation grounds and use of a single Linsen flotilla, which had already operated in support of the Army, was mooted instead.
Admiral Frisius in Dunkirk suggested that the K-Verbände units still in the Netherlands should move instead to Dunkirk from where they could continue operations against the Scheldt traffic. Frisius’s idea was based on the fact that the Seehunds remained the only craft of sufficient range to reach their allocated combat area from German bases, though his proposal was ultimately rejected and the K-Verbände fought on in Holland.
The bad weather that had dogged Fröhnert and Beltrami on their way to Dunkirk remained in place until 5 April after which operations were resumed. The Seehunds immediately began sailing, directed against the Thames-Scheldt convoy routes as well as the supply lines that traversed the British coast east of the Thames and as far as Dungeness. Seehund strength on 8 April in Ijmuiden was recorded as twenty-nine, of which only perhaps half were operational on that day. Reinforcements were scheduled to arrive from Germany; eleven Seehunds heading from Neustadt on 18 April to Wilhelmshaven and ultimately Ijmuiden, shepherded as far as Brunsbüttel by the armed trawler KFK445. The Seehunds had originally been intended to relocate to Heligoland but increasingly heavy air raids had rendered the island virtually unusable. Four other Seehunds arrived in Ijmuiden from Wilhelmshaven on 20 April and three more by the beginning of the following month, bolstered by a further two from Heligoland.
In total thirty-six Seehunds put to sea on war patrols between 5 April and 28 April, the maximum effort achieved on 12 April when sixteen boats were at sea. Of the thirty-eight that sailed, eight returned prematurely with defects, fifteen returned safely, six were recorded as definitely lost by 28 April, three unaccounted for and four were still at sea on that date. Only three of them reported successful attacks.
The first, U-5309, crewed by L.z.S. Benediktus von Pander and Lt(Ing.) Martin Vogl claimed a 1,000-ton tanker hit north-north-west of Dunkirk on 9 April, the day before they returned to Ijmuiden. The American army tanker Y17 had been hit and set ablaze by a torpedo in that approximate position while part of convoy TAC90. The 484-ton ship was one of the small tankers operated by the US Army. They were of a standardised design, similar in size and appearance to the Navy Yard oiler, though designated as ‘Y’ boats. These vessels were built for the Transportation Corps in two classes, a twin-screw version and a single-screw version, Y17 belonging to the latter. Burning fiercely after the magnetic torpedo exploded beneath the hull, Y17 was lost in less than thirty minutes after being hit.
Seehund U-5363 attacked convoy TBC123 off Dungeness late on 9 April, the British Liberty ship ss Samida hit and sunk and the American Liberty ship ss Soloman Juneau damaged a little before midnight. Again, there is confusion over who actually hit the two ships, German B-Dienst listening service crediting the Type VIIC U-245 engaged on Dönitz’s inshore campaign with the attack, though her captain denies that he was responsible. The likelihood is that it was L.z.S. Harro Buttmann and Omasch. Artur Schmidt’s Seehund that inflicted the damage, though the German midget was subsequently lost to an attack by ML102 during the action and both crew killed. Schmidt’s corpse was recovered during August 1945 in fishing nets near Föhr Island, his remains interred in Wyk cemetery. At around the same time that U-5363 was sunk by the British motor launch, Beaufighter ‘W’ of 254 Squadron accounted for another of the Seehunds destroyed during that month.
Markworth and Spallek’s U-5070 obtained a hit on an estimated 4,500-ton ship from convoy UC63B near Dungeness on 11 April, successfully torpedoing British ss Port Wyndham though the 8,480-ton Port Line ship survived the attack. Hit twice off the outer Lade Buoy at Dungeness the ship was holed forward, later being towed stern-first into Southampton where she was given temporary repairs prior to permanent work being completed by her builder. U-5070 had little time to celebrate as an escorting destroyer, HMS Vesper, hammered them for several hours with depth charges before they managed to limp silently away.
L.z.S. Reimer Wilken and Omasch. Heinz Bauditz aboard U-5368 made the third Seehund claim though in hindsight their target appraisal remains optimistic. They recorded two hits, the first against a corvette on 14 April that they fired at from a range of 800m, the second a 5,000-ton ship hit two days later at 18.30hrs from 1,000m. There is no Allied record of the former but on 16 April the 1,150-ton British Post Office cable layer ss Monarch was torpedoed near Orford Ness, this likely to have been Wilken’s target. Nonetheless, it was a successful and aggressively handled patrol, U-5368’s two crew expending their boat’s last reserves of diesel by 18 April, the incapacitated Seehund drifting ashore five days later near Katwijk.
In Ijmuiden there were also two further successes transmitted to Brandi’s men by the B-Dienst. On 18 April two ships from convoy TAM142 were torpedoed half a mile from the South Falls buoy early that morning, the Norwegian freighter MS Karmt and British steamer ss Frilleigh subsequently sinking. However, the attribution to Seehund attack appears to be misplaced as U-245 logged the attack in its own War Diary, making Seehund involvement unlikely.
The returning crews also reported three unsuccessful attacks during their patrols. The most dramatic narrow escape was undoubtedly suffered by Oberfähnrich Korbinian Penzkofer and Obermaschinist Werner Schulz’s U-5305 after an attempted attack on a destroyer in the South Falls area on 10 April. The port torpedo was readied to fire at the British warship, but failed to disengage, dragging the terrified crew through the water toward their enemy. As the Seehund shot underneath the ship the magnetic warhead failed to detonate and after a severe counter-attack from the startled British crew that involved a great deal of machine gun fire at the crazed midget that was apparently attempting to ram a British ‘Hunt’ class destroyer, U-5305 was able to creep away from the scene and return to Holland. U-5071 also recorded near disaster when they were attacked while homebound and still carrying their torpedoes. A splinter penetrated the warhead of one torpedo, though it failed to explode.
Aircraft continued to be a prime predator of the Seehunds, at least 1,000 of them being involved in anti-Seehund patrols, alongside 500 naval vessels. Mosquito ‘H’ of 254 Squadron, Wellington ‘V’ of 524 Squadron and Beaufighter ‘M’ of 236 Squadron combined to destroy a returning Seehund off the Hook of Holland on 12 April. The following day Barracuda ‘L’ of 810 Naval Air Squadron attacked another in the same area.
Friday 13th: New patrols now being flown off the Dutch coast… S/Lt McCarthy made an attack on a midget some 14 miles off the Dutch coast. The attack was successful, two survivors coming to the surface! S/Lt Taylor made an attack on a disappearing contact, but no results were observed. S/Lt Bradbury made an attack on a midget during the last patrol. Nothing came to the surface. But it can be assumed to be a probable.
Unbeknownst to the men of 5. K-Division the bloodbath was over for them as of 28 April. The final four Seehunds to run supplies into Dunkirk, U-5365, U-5074, U-5090 and U-5107, were the last of their kind to be on active patrols. There they would see the end of the war, later destroyed by their own crews before Dunkirk eventually capitulated.
Chaos had overwhelmed the German military in Holland during April. As Dutch harbours and installations were prepared for both defence against ground assault and destruction in the face of possible German withdrawal, Georgian troops that were serving in the Wehrmacht on the island of Texel revolted on 8 April. It was two more weeks before German soldiers managed to subdue the rebellion, the same day that the locks at Ijmuiden were destroyed by demolition. Dutch resistance members reported German morale to the British as ‘low’, though not among ‘younger elements’ which may well have included the K-Verbände. Looting began to increase amidst the breakdown of military order, though Heye’s men remained disciplined and loyal to the very end.
While the Seehunds had helped carry the war back into British home waters, the Bibers and Linsens had continued their desperate onslaught in the Scheldt, sixty Molchs being held in reserve in Amersfoort. In the early afternoon of 9 April, five Bibers armed with a mine and torpedo each had sailed for the Scheldt estuary. Two were forced to return within two days with mechanical defects, one striking a mine and sinking en route, while the remaining three were lost without apparent success, Beaufighter pilots of 236 Squadron and Swordfish of 119 Squadron reported attacking and hitting Bibers within the area.
For the Biber pilots the emphasis moved completely to mine laying and on 11 April two Bibers sailed from Zierikzee to lay their mines before Sandkreek. One accomplished its mission successfully while the other was lost. Swordfish of 119 Squadron probably accounted for the missing Biber, their logbook entry echoing what had become regular reports for Allied airmen as they harvested a grim tally of Biber kills.
April 12: Swordfish ‘F’ … Scrambled to search for Bibers reported approximately 40 miles north of base. At 15.10hrs two were sighted in position 0051°54’N 0003°17’E, one stationary on surface, the other just surfacing about 50 yards away. The first Biber apparently attempted to submerge but the conning tower was still visible when ‘F’ attacked with four depth charges. The stick fell between the two, the first one being blown out of the water and left stationary on the surface. The second was not seen again.
At 06.30hrs on 21 April the penultimate Biber mission in Holland was launched with six leaving to lay mines in the silt of the Scheldt estuary. Only four of them returned.
On 26 April the final recorded Biber mission from Dutch territory took place when four left Poortershaven at 01.30hrs to lay mines again in the Scheldt estuary. One grounded while outbound and was forced to return with damage. American Thunderbolt fighters off the Hook of Holland attacked the remaining trio, two of them sunk in the battle. The sole survivor escaped the prowling aircraft and aborted his mission, returning to base. During April, the twenty-four remaining Bibers that were in the Rotterdam area had all taken part in missions. Of these, nineteen were lost with no sinkings or damage of enemy ships attributed to their missions. The defeat of the Bibers was complete.
The last active component of the K-Verbände in Holland – that of the Linsens – had also comprehensively failed in its missions during April. Weather conditions moderated enough by 11 April to allow a resumption of their operations. Five units put out from Hellevoetsluis to attack shipping off Ostend during that evening. One unit reached the target area and unsuccessfully attacked an Allied patrol vessel. Of the remainder, one unit returned with mechanical problems, two failed to find the target area and another unit was lost in action. The same mission plan was repeated on the night of 12 April by seven units in total. Two of the control boats were also tasked with landing agents ashore in enemy-held territory, but the mission was scrubbed due to an unexpectedly heavy swell.
Five nights later two formations of Linsens set out once more. Two units were to attack enemy shipping in the Scheldt estuary again, while the remainder were destined to head for Dunkirk and continue their operations from there against the Thames-Scheldt convoy route as Frisius had suggested. The former returned with engine trouble while the fate of the latter remains unknown and conjectural.
At 21.30hrs on 20 April the last recorded Linsen operation began with four units slipping from Hellevoetsluis to attack Allied convoy traffic due around buoy NF8 at 02.10hrs and from there to sail onwards to Dunkirk at 04.00hrs. Two units aborted with engine trouble while the others were hammered by Allied naval vessels and aircraft west of Schouwen a little before midnight and obliterated. Once more the MTB control frigate HMS Retalick and its four accompanying MTBs were heavily involved in fighting the K-Verbände. The British report on the action paints a harrowing picture of the demise of the Linsen unit.
An overcast night but owing to the moon behind the clouds, one of reasonable visibility.
Both MTB units (FH3 and FH4 of two MTBs each) were established in position … Aircraft reporting at 22.26 a persistent contact… At 00.16, a small radar echo bearing 355°, 1.8 miles stationary and thought to be a midget submarine. Range closed at high speed and snowflake [illumination flares – author’s note] used. Target (I) seen to be a small motorboat, which was engaged as it started to move. Immediate hits were seen, it burned fiercely and stopped.
In the glare of the burning boat a second (II) was seen … this was pursued but contact was lost at 00.21 … At 00.33 EMB (III) was sighted after radar contact, pursued, engaged and seen to burn at 00.38.
Seen through the smoke from III, IV was seen, pursued, being destroyed at 01.00. A survivor was recovered from the water. FH3 and FH4 were vectored to search for survivors and wreckage. Depth charges were dropped at 00.49.
HMS Retalick recorded the destruction of four Linsens and another probable before the battle ended. The British had suffered no casualties or damage and gathered together the few shocked survivors.
The prisoners recovered were the leader, Oberleutnant zur See [Karl] Feigl and his coxswain [Bootsmaat Robert] Klein, both of whom were dead, having had the major portion of their heads shot off. Both [Matrosenobergefreiter Walter] Kettemann and [Funkgefreiter Günther] Mellethin, who were alive (Kettemann with his arm broken by gunfire) were in separate boats. They kept on enquiring for Schultz another member of the unit, whom one had seen in the water … Feigl had a chart and his orders on him.
The prisoners stated that after the death of their leader … they were thrown into confusion. It would appear that they were not individually briefed. They were of an excellent physical type and ardent members of the Hitler Youth.
With this characterisation in mind there remains one truly bizarre postscript to the K-Verbände operations in Holland. German naval documents reveal that on the night of 27 April at least thirty volunteers from unspecified K-Verbände units were to be heavily armed and flown to Berlin where they would act as a personal bodyguard for their Führer Adolf Hitler. They apparently got as far as assembling at the aerodrome at Rerick and preparing to board three Ju52 transport aircraft before their mission was abandoned – the sole reason for this cancellation appearing to be the expected inability to land men in the besieged German capital.
On 6 May 1945 the Royal Canadian Hastings and Prince Edward Regiments of the 1st Canadian Division took the surrender of German forces in Ijmuiden. Among the battered remnants of many Wehrmacht formations, the K-Verbände men marched into captivity with their commander K.z.S. Albrecht Brandi.
There we, 3,000 comrades of Brandi’s K-Verbände, were taken into custody. Since he, ‘Diamonds-Brandi’, had a huge reputation with our enemies, even more so than with the German public, the Canadian General and his men passed on this reputation to us … After we had cleaned our weapons and had them inspected one last time, we transferred them all complete with ammunition to a detail of trucks. Then in good disciplined order we marched as ‘Marine Division Brandi’ into a camp of tents, equipped with a special food supply. The next Allied order was that no military honour with the Swastika on it could be worn, so we deployed close to the town square. Then Brandi spoke to the assembled troops. ‘Our decorations are bestowed by our highest commanders, and if we are not able to wear them in the form given to us, then we will lay them down!’ Then he took off his Knight’s Cross with Oak Leaves, Swords and Diamonds, along with 3,000 comrades that did likewise. We marched silently back into the camp.