Seehunds in the Thames Estuary II

During February there had been thirty-three Seehund missions, four of the Seehunds being lost in action. Despite these losses and the destruction of several machines that had been run aground, for the first time the month ended on an optimistic note for the Seehund crews as victories appeared to be on the increase.

Linsen operations had been delayed by bad weather in the latter half of February though three units departed Hellevoetsluis on the night of 21 February in search of targets within the Scheldt. Two of the units turned back with engine problems, while the third searched in vain, forced to scuttle one boat due to lack of fuel. Molchs too had begun operations in the Scheldt that same night. Ten were towed to the Scheldt and four others setting out from Hellevoetsluis under their own battery power. This operation marked the beginning of an almost suicidal undertaking – Totaleinsatz, or, ‘total commitment’. K-Verbände planners only envisioned the possibility of a maximum of four boats returning. Nevertheless, at least two-thirds of the Molch crews volunteered on 22 February for what they were told was probably a one-way mission. As it transpired, eight Molchs returned, but claiming no results. B-Dienst listening service indicated that Allied forces off West Kapelle sank three and captured two men. Three further Molchs were destroyed at their depot at Assen and another three damaged by air attack on 21 February.

The general situation for the German armed forces was dire in the extreme as March dawned on an increasingly beleaguered Wehrmacht. In conference with Hitler on 26 February Dönitz had suggested that Seehund attacks be concentrated against the Thames area as aerial reconnaissance had shown large shipping concentrations there. The latest Seehunds possessed an increased combat radius due to the addition of external saddle tanks as standard fittings and he expected better results than achieved previously. He also stressed the necessity of maintaining Dutch ground for the K-Verbände if it was to be able to operate effectively. Indeed the SKL later pointed out that the maintenance of Dutch roads and railways was vital to K-Verbände operations, since it was only from the Netherlands that Seehunds could reach the Thames under their own power, let alone the Biber, Molch and Linsen operations. Requests to transfer some Seehunds to the Mediterranean were declined by Dönitz, at least until a strength of eighty machines was reached in Ijmuiden. Dönitz countered this proposal with an idea to ship a Marder unit to Rhodes, though the Luftwaffe representative at Führer headquarters, Oberst-Leutnant von Greiff, replied that an undertaking of that nature would only be justifiable if of extreme strategic significance due to the fuel requirements and the necessary reallocation of Ju290 transport aircraft. The idea was immediately abandoned and the K-Verbände fought on as before. The sole addition to their arsenal was a so-called ‘Marder simulator’ which comprised a Plexiglas Marder hood from which was suspended an explosive charge that would be exploded by ramming. It is unknown if they were ever deployed, but a shipment of them bound for the frontline was definitely destroyed in an air attack on Rosenheim on 6 March.

Adverse weather forced a suspension of K-Verbände operations until 6 March when Seehunds and Bibers were once more cleared for action. For the Bibers it was also another day marked by disaster as they gathered ready to put to sea. In the crowded harbour basin at Hellevoetsluis, ten minutes before the Bibers were due to commence departure, a pilot accidentally released his torpedoes sinking fourteen Bibers in the resultant explosion and damaging another nine. Only eleven Bibers were left in a seaworthy state following this fresh accident, but they all sailed for the Scheldt that evening. None of them returned. One was captured by a British motor launch off Breskens on 7 March, another sunk by coastal artillery fire off Westkappelle the following day, four found abandoned ashore on the coastline at North Beveland, Knocke, Domberg and Zeebrugge. The remaining five vanished without trace. Undeterred, the assault against Scheldt shipping continued with six Linsens leaving Hellevoetsluis on the night of 10 March to attack the Veere anchorage on the northern Walcheren coast. Sighted by shore batteries they were driven away by heavy fire, leaving two boats grounded behind them.

The following night a combined massed operation was launched by using fifteen Bibers armed with torpedoes and mines, fourteen Molchs and twenty-seven Linsens, all targeting shipping in the West Scheldt. The results were predictably disastrous; thirteen Bibers, nine Molchs and sixteen Linsens lost for no result. Of the Biber casualties, the RAF’s 119 Squadron off Schouwen sank two on 11 March.

During the afternoon F/LT Campbell took up the Anson on an air test cum /ASR flight (searching for an aircraft lost on 9 March) … Having a keen eye, he spotted something suspicious in the sea 10 miles east of Schouwen and on flying down to investigate identified the conning tower of a Biber. No R/T, no W/T, but remembering his early training, he switched his I.F.F. to Stud 3 trusting it would be picked up and understood but it wasn’t. As the Anson was unarmed there was no possibility of attacking the midget, but a spot of ‘beating up’ was attempted without, however, shaking the Jerry sufficiently to make him do anything silly. After several attacks it was eventually given up as a bad job, and the aircraft was just making for home when lo and behold! Another little Biber made its appearance about a mile away. Campbell tried out the same tactics, and this time success greeted his efforts for the ‘U-Boat Commander’ (as the subsequent newspaper story dubbed him) evidently didn’t like the feel of an aircraft roaring over him at twenty feet, and on the third dive pilot and observer glimpsed one large rump disappearing over the side of the U-boat. On the final return a figure was seen trying to struggle into a dinghy, the midget turning turtle and slowly disappearing beneath the waves. ‘Killer’ Campbell returned to make his report and Swordfish ‘H’ … immediately took off followed in a few minutes by ‘R’… to search for the U-boat that was still at large.

At 18.25hrs at position 51°48’N 03°31’E, Flying Officers Corbie and O’Donnell aboard Swordfish ‘F’ sighted the Biber’s cupola as it surfaced, and attacked with four depth-charge runs. The last exploded almost directly beneath the Biber which was enveloped in spray and disappearing, leaving just a thick oil slick on the disturbed surface of the sea. The second Swordfish then arrived and dropped four more depth charges on the oil streak to ensure the Biber’s destruction.

The following day Swordfish ‘E’ of 119 Squadron encountered Linsens for the first time, sighting three and diving to release depth charges and strafe the Linsens below, disabling one which was seen to be ‘lower in the water after the shoot up’ and later still found floating abandoned on the swell. Further Swordfish encountered more Linsens, attacking and then calling for support from two Tempest fighter-bombers of 33 Squadron who destroyed the sighted Linsens with strafing, a single survivor seen floating in the wreckage.

The run of success enjoyed by 119 Squadron continued that day as two more Swordfish encountered Bibers, both subjected to depth charge and machine gun attacks rewarded by both Bibers sinking and in once case a small yellow life raft observed amongst the oil slicks, the other leaving only wreckage and oil behind. The jubilation felt by the Swordfish crews was reflected in their Squadron Log Book: ‘Four Bibers in two days! Whizzo!’ Two days later Swordfish ‘D’, engaged on a similar anti-Biber patrol, arrived on the scene of a single Linsen being circled by a Warwick and Beaufighter. Soon a Walrus flying boat of 276 Squadron arrived and landed beside the solitary German to pluck him from his disabled boat.

Four more Bibers were sunk by MGBs off Westkappelle, another four by shore batteries at Vlissingen and Breskens on 12 March. That same day a Spitfire attacked and sank a Biber off Walcheren and the following day HMS Retalick engaged another.

At 02.17hrs a midget submarine, Type Biber, was observed inclination 90 right dead ahead. Speed was increased to maximum and Pom-Pom opened fire. The submarine passed close down the starboard side and five charges, set for 50 feet, were fired. The submarine by then was very low in the water, and passed within ten feet of the starboard side at 02.27hrs. A five charge pattern, set for 50 feet, was fired. The charge from the starboard thrower was observed by myself to fall over the submarine. There was a particularly violent explosion and all trace disappeared. There was no doubt that the submarine had been hit repeatedly and was probably sinking before the last pattern was fired.

Gunners aboard HMS Retalick swore that they had also seen another Biber nearby during the attack, so the ensuing search for a survivor was brief and unsuccessful.

The massacre of the Bibers, Linsens and Molchs would continue throughout March. Linsens had also been deployed against the Thames estuary for the first time on the night of 11 March, carried into action aboard the converted S-boats. Launched in the South Falls area at midnight against a TAM convoy that had been sighted at a distance of 18 miles, the attack was unsuccessful. The sole German reference to it was that three control Linsens, carrying the pilots of their expended explosive boats, grounded the following morning near the Goeree lighthouse, where they were destroyed and the men killed in an Allied air attack. Linsens were also sortied on the nights of 22 March and 26 March without any success.

During the night of 23 March, sixteen Bibers armed with mines and torpedoes left Hellevoetsluis for the Scheldt estuary once more. This time there were more survivors as seven managed to return though with no successes. Of the remainder one was found abandoned on Schouwen and another sunk by Beaufighters of 254 Squadron off Goeree. Beaufighters ‘R’ and ‘G’ of 254 Squadron engaged on anti-Seehund patrols sighted the Biber at 09.40hrs on 25 March, circling the surfaced craft that appeared to be stationary and listing slightly with the operator standing atop the hull next to the conning tower. Consideration was given to capturing the Biber and the two Beaufighters circled while awaiting notification of whether a motor launch was close enough to assist. Two hours after first contact the aircraft were instructed to sink the boat and attacked immediately.

‘R’ made two attacks and ‘G’ four attacks, one-man crew seen to jump overboard and enter dinghy. He was last seen paddling away with both feet making his way to the distant Dutch coast.

HMS Retalick took a heavy toll on the Bibers deployed. The after action report submitted on 24 March recounts the ship’s actions against the attacking midget submarines as the battle soon developed into chaos.

At 19.41 when in position 293° Westkapelle 9.75 miles, Course 030°, Speed 14 knots, a small radar echo was detected at 030° 2 miles … At 19.48 Asdic contact was obtained, two echoes being recorded on trace … before a five charge pattern set at 100 feet was fired …

Course was maintained at reduced speed … and a second attack made … At 20.02 a third and deliberate attack was made.

The area was illuminated and at 20.15 shouting and whistle blowing was heard and two men were clearly seen in the water. All the bridge personnel saw these two men, one of whom (subsequently recovered) was very active, the other bleeding from the mouth was much quieter. Their pale grey clothes and red or orange life-belts were unmistakable. An attempt to recover them was made when it was realised that this might invite disaster, and a calcium flare was dropped, FH3, MTB493 being instructed to recover the survivors. He could only find one however, and after some time had elapsed at 21.14 Fähnrich Heinz Lehne was placed on board.

The prisoner was most emphatic that his was a one-man craft, nevertheless there were two men in the water. The plot shows some discrepancies as to the position and it may be that two midgets were close together, one attack being delivered on one and one attack on the other and both destroyed.

At 21.24 … a small radar echo was detected …

HMS Retalick engaged the third Biber with depth charges and cannon fire when an object was blown to the surface. Gunners reported the propeller of the midget submarine thrashing in the air as the Biber went down in a spume of churned water, Retalick herself violently shaken by an underwater explosion that was probably the midget’s torpedoes. The third ‘kill’ rendered no trace and at 02.37hrs another radar echo was established. Racing to intercept the Biber was seen on the surface as snowflake was fired above it. Cannon fire peppered the Biber as it passed to starboard, hammered as well by a full depth-charge pattern. Two large oil patches were all that marked its obliteration.

Aboard Retalick there was understandable jubilation at the destruction of four Bibers. Lehne was brought aboard soon afterward for interrogation and to have his effects examined. Amongst the usual equipment found on him were:

Leave tickets, photograph folder, photographs (personal), newspaper obituary and cuttings.

His initial interrogation revealed to the British that he:

… had served in submarines for six months. Was hit by the first pattern, and escaped after his submarine was holed, using escape apparatus: was the member of a mobile unit, and was out with several others proceeding independently.

Most insistent that he was the only man in the submarine. He was no Nazi, but a German citizen and his duty was to his country. No one in his service had yet returned from an operation. It was a suicide job, he did not expect to return. He was partial to the English, but opposed the Russians.

HMS Retalick had destroyed four of the six Bibers, the remainder disappearing without trace. Of the fifty-six Bibers and Molchs which sortied in March 1945, forty-two had been lost for no result.

The SKL were appalled by the results of these brave though doomed missions. They appealed for greater assistance from the Luftwaffe who were asked to bomb the docks and locks at Antwerp to delay Allied stores from being unloaded. The K-Verbände were obviously not having the desired affect on Allied supply lines with which the German Army struggled against on land. The German Naval Staff complained to OKW that counter-measures against the various midget services had been intensified, including the use of ‘old biplane aircraft’ which by virtue of their slow speed were capable of a more thorough search for targets below.

Fortunately for the men of the 1st and 2nd Seehund Flotilla, their two-man submarines fared better during the month of March. German records remain incomplete for this period, so the events can only be gradually pieced together. During March thirty-one Seehunds sailed, though two that put to sea on 13 March stranded outbound; one near Katwijk and the other near the Hook of Holland. Both crews were rescued, but their boats are not in the list that follows. The attackers mounted two distinct waves focussing on different regions, the first spanning from 6 to 19 March, the second 24 to 26 March.

6March – five boats sailed for Margate Roads and the Elbow Buoy, four boats for Great Yarmouth area.

9March – three boats sailed for Margate, one for Great Yarmouth.

11March – two boats sailed, one for each of the above stations.

16March – again one boat for each station.

19March – two boats sailed for Great Yarmouth.

24March – three boats sailed for the Thames-Scheldt convoy route, two for the British east coast north of the Thames.

25March – one boat sailed for each of the above areas.

26March – two boats sailed for the convoy route, one for the Thames.

Again Harald Sander was aboard one of the Seehunds that were active off the English coast. After his experiences during February, when his Seehund was wrecked, he had been allowed time to return to Germany before putting to sea once again.

Admiral Heye … said, ‘Harald, go home to Berlin for eight days and then from there go back to Wilhelmshaven and get yourself a new boat’. Then I told him that I didn’t really get on with my companion. ‘Okay, find yourself a new commander. We still have some in training’ … It wasn’t easy coming to Berlin because the ‘chain dogs’ were in operation … Mr Himmler and Adolf had formed these troops that were a sort of military police force and they wore chains. Everyone running around in Berlin and elsewhere was gathered together by them as troops for the Berlin defence. This was already the end of February and the Russian troops were advancing on Berlin. I had a special pass of course, so that they couldn’t recruit me. I had papers from Heye stating that I was in the ‘K group’ so they couldn’t send me off towards Russia.

Then the scheme started again from the beginning. Pick up a boat in Wilhelmshaven, then run it in, then we travelled from there by train. The whole ten boats in the flotilla were loaded onto a train. We had the infantry there as guards and we travelled by night. By day we halted at the border in a siding under guard and then we continued on, arriving in Ijmuiden after the second night. And then we ran the boats in again. Down there at the Scheldt it was different now. The invasion was more advanced. Then I was given the job of going to Great Yarmouth with my comrade. If a line is drawn directly from east to west from Ijmuiden you come to the corner of England where the port and the city of Great Yarmouth are situated … In two days we chugged across, lying low by day and continuing by night, because the boat couldn’t move fast … Then in Great Yarmouth we went to ground and the next day from a long way off we heard the sound of two ships and then we surfaced. There was a destroyer and a big commercial ship. At the time we estimated about ten or twelve thousand tonnes. It was behind the destroyer. Okay, it was a target and we wanted to try it out. We dived again until the destroyer had passed overhead and then we went down to sea bed level and my commander tried it out. I had to pull both the levers which were behind my chief engineer’s seat in order to free the torpedoes – first one lever and then the other. There was no explosion.

Well after firing we dived straight away and stayed on the bottom and then we had to be quiet. We couldn’t make a sound, no sound of metal, otherwise the English would start to attack immediately. Then came the sonar ‘Asdic’, as it is called… it sounded as though a handful of gravel was being thrown against the outside of the boat. There is this ticking noise, which comes at intervals. Then it was quiet for a while and then we heard the destroyer returning. The other boat, the freighter, of course, had kept moving and then the destroyer came looking for us.

That took a couple of hours. Either they changed position, or we changed position and when they changed position we moved as well, because it was sound against sound. And then when they were quiet and stopped moving they were looking for us, so we remained still. The whole thing went like that and they dropped about thirty depth charges on us. We weren’t hit directly, otherwise I wouldn’t be here, but they kept trying by dropping depth charges in our general position. They kept this up for a while and then afterwards we were so far away and we were really quite a small target. The boat is not quite one metre wide and with a length of twelve or thirteen metres it is not a big target to pinpoint. So we were in luck again and then we went home by night. We landed in Ijmuiden again and that was towards the end. It was already late March or early April of 1945. At that time the Canadians and the English were steadily advancing towards us.

Of the nine boats that sailed on 6 March, Oblt.z.S. Ross, L.z.S. Gaffron, L.z.S. Gohler, L.z.S. Drexel and L.z.S. Markworth were all forced to return with technical faults. One other was sunk by MTB675 26 miles east of Ramsgate on 7 March.

Over the remainder of the month several more Seehunds were lost. The confusion of reported attacks and sinkings from Allied sources and a lack of German records that detail losses, returning boats and sailing dates mean that only estimates can be made of the scale of sinkings experienced by the Seehund units. It is thought that at least fifteen boats were lost, possibly more.

As well as the confirmed sinking made by MTB675, there are several other definite German losses. One Seehund was lost to a Beaufighter attack on 10 March near Goeree, another sunk the following day and L.z.S. Newbauer taken prisoner. Two Seehunds were sunk by HMS Torrington; the first, U-5377, near Dumpton Buoy on the edge of Goodwin Sands on 11 March, the second, U-5339, 20 miles north of Dunkirk three days later. The hunt for this second Seehund caused considerable damage to Torrington herself, the engine and boiler rooms suffering from the concussion of depth charges set for 50 feet and exploding in shallow water. During the bombardment the wire rope lanyard that operated the starboard depth charge thrower parted following the first salvo. Its operator, Able Seaman Charles Horton, picked up a duffel coat and wrapped it around his head as he continued to fire the thrower by hand, burning his face and hands until the Seehund was destroyed.107 Leutnant zur See Siegert and Maschinenmaat Heilhues of U-5377 were both taken prisoner, picked up by MTB621 and later transferred aboard Torrington. Five minesweepers reported sighting and attacking a Seehund on 13 March northeast of Felixstowe. HMML466 attacked and sank a Seehund on 12 March in drifting fog, capturing the coxswain L.z.S. John but killing MascMt Teichmüller with machine gun fire. L.z.S. Hermann Bohme and his coxswain were also listed as killed by fighter-bomber attack on 12 March west of Schouwen. On 21 March enemy aircraft attacked L.z.S. Gohler and Omasch. Kassier as their boat sortied from Ijmuiden after the rectification of their technical problems – the boat was sunk and both men lost. Another Seehund of the first wave of attackers was sunk by MTB394 23 miles south-east of Great Yarmouth on 22 March, both crewmen rescued.

The second wave that had slipped from Ijmuiden between 24 and 26 March fared little better, losing one Seehund to Beaufighter attack at 14.40hrs on 25 March 20 miles north-west of the Hook of Holland, though misidentified by the attacking crew.

Aircraft ‘Q’; F/O B.V. Ekbery, F/S Thomas on Anti-Seehund patrol. 14.40: 52°12’N, 03°45’E. Sighted wake dead ahead and identified as conning tower of a midget U-boat, believed to be a Biber. Aircraft attacked with cannon as U-boat was crash diving. Hits were probable but target was hidden by splashes. About three minutes after attack a patch of thin oil was seen, about 15ft in diameter in approximate target position.

Another Seehund was lost to HMS Puffin off Lowestoft in the early morning of 26 March. The ship rammed a Seehund, the subsequent impact causing a torpedo to detonate, obliterating the Seehund and buckling the British ship’s bows, HMS Puffin limped into Harwich where the damage to the ship was judged so severe that she was not repaired. In Jürgen Rohwer’s book on U-boat successes he states that: ‘HMS Puffin was obviously rammed by a surfacing midget, which had already been abandoned.’

The same day that Puffin made her attack, the Royal Navy motor launch ME1471 sank a Seehund, and perhaps the final German victim for March fell to ML586 the following day west of Walcheren.

Their attempts were not without success though. On 10 March L.z.S. Lanz and Lt(Ing.) Gerhard Müller’s U-5364 recorded a successful torpedoing of a destroyer, though Allied records hold no mention of this. However, on 13 March the 2,878-ton Canadian steamer ss Taber Park taking coal from the Tyne to London was torpedoed by L.z.S. Maximilian Huber and Lt(Ing.) Siegfried Eckloff. The ship was travelling out of convoy and sank rapidly, killing four DEMS gunners and twenty-four crew out of a total of thirty-two people aboard. Two of the Seehunds operating within the Thames area claimed two ships sunk, Fröhnert and Beltrami claiming a steamer hit before they were subjected to a devastating depth charge bombardment that they narrowly managed to sneak away from and return bruised but intact to Ijmuiden. Kruger and Schmidt’s U-5064 also claimed a large steamer, estimated at 3,500 tons sunk in the Thames Estuary. Neither claim has been firmly corroborated by Allied sources.

On 21 March Hauschel and Hesel’s U-5366 torpedoed and sank the American Liberty ship ss Charles D. Mclver southeast of Lowestoft. Enroute to Southend from Antwerp and then planned to head onward to New York, the Liberty ship was at first thought by Allied sources to have been mined, though the attack coincides with that reported by the crew of U-5366. On 22 March ML466 was sunk by what has been suggested was a Seehund torpedo, though no surviving crew claimed the attack. More definite was the torpedoing by Küllmer and Raschke of the British steamer ss Newlands within the Thames Estuary. Newlands was hit with a shot fired from 320m, the Seehund escaping to return to Ijmuiden. The last sinking attributed to a Seehund for March was the successful torpedoing of the British coastal freighter ss Jim travelling from Goole to Dieppe.

The pressure on the Seehund crews was increasing during March as Germany tottered towards annihilation between the Russian and Western Allied forces. In Ijmuiden the USAAF returned to attack the concrete pens twice more; nine B-17s using ‘Disney’ rockets on 14 March, three more returning with the same payload a week later. March had yielded some more hopeful results for the midget service though, with Seehund attacks taking their toll despite a total of fourteen men definitely killed on operations and at least the same number captured.