The German Biber midget submarine – part one; Biber 90 at IWM London 1946

Richard Maddox

IT MUST HAVE BEEN AN EERIE SCENE that confronted Royal Navy minesweeper HMS Ready, on 29 December 1944 off Northforeland, a promontory on the Kent coast of southern England.

The boat from HMS Ready nears the German Biber submarine. Image © IWM (A 28249).

A hawser is rigged from HMS Ready, so that the submarine can be taken in tow. Image © IWM (A 28249)

The ship had gone to investigate what was thought to be a marker buoy drifting out of position. Instead the crew found a small grey painted German submarine slowly sinking, the waves lapping against its steel hull.

The minesweeper probably watched and waited adding to the silence. On the ship’s bridge, binoculars scanned the winter sea and sky.

The submarine was a ‘Biber’ (‘Beaver’ in English) class midget submarine. Length just 29.5 feet (9m) long with a crew of one. On her conning tower was the pennant number ‘90’.

The sole crewman (or ‘pilot’) would turn out to be Joachim Langsdorff, son of Kapitän zur See (Captain) Hans Lansdorf who while in command of the damaged German cruiser KMS Admiral Graf Spee had scuttled the ship in the River Plate off Montevideo in far-away Uruguay in December 1939.

A boat launched from the British ship. Warily it approached the German vessel and a line was attached.

But there was nothing to fear. Joachim Langsdorff was dead at the controls. He had died of carbon monoxide poisoning sometime after setting out from Hellovoetsluis in the Netherlands.

Slowly HMS Ready towed the tiny submarine the fifty miles to Dover Harbour.

Once there the submarine sank near the harbour entrance.

Not to be cheated of their prize it was later raised by the Royal Navy and with other captured and abandoned Biber boats – including Biber No. 105 now at the Royal Navy Submarine Museum at Gosport Hampshire – minutely examined and documented. (2)

During extensive trials Biber No. 90 was found to be unsafe and was modified to make it safe for the men (chiefly Lieutenant Commander Arthur Connuch Halliday RN a very experienced submariner) (3) who tested it.

Even so, with at least one report of the vessel catching fire because of an electrical fault (4) – Halliday claimed replacement uniform items after his were damaged (5) – working with the vessels, even on dry land was always a potentially hazardous venture.

Langsdoff’s vessel was one of 324 Biber submarines operated by the nine flotillas of the Kleinkampfverbände der Kriegsmarine (the German Navy’s Small Battle units). (6) He had set sail on 27 December, two days before his vessel was found. Of the 14 that were prepared for patrol, eleven were destroyed with the remaining failing to return. (7)

Besides midget submarines, the unit also operated fast boats equipped with high explosives as well as combat divers. Their targets were – unsurprisingly – shipping supplying the allied armies pushing across Europe and transport structures such as canals and bridges.

The Biber’s design was apparently influenced by that of British Welman boats – a specialist midget submarine designed to be operated by Britain’s Special Operations Executive.

Although the use of Welman boats was abandoned by the British after a single unsuccessful mission when a boat was captured intact by German forces on 21 November 1943 in the Norwegian port of Bergen, Kreigsmarine Korvettenkapitän (Lieutenant Commander) Hans Bartels saw the potential for a German low-cost and easy to operate submarine – the Biber was born.

In February 1944 a prototype was constructed by the Flenderwerke shipyard at Lübeck in northern Germany and undertook initial trials on 29 March 1944, much of which was carried out by Bartels on the River Trave in Schleswig – Holstein.

In all some 324 units were delivered in seven batches during 1944. (8) Operational vessels were organised into nine flotillas under Bartels’ command to form Lehrkommando 250. This unit was self-contained and responsible for training crews and for operational deployment. (9)

The first mission was to attack shipping supplying the Allied Invasion beaches and submarines were launched from Fécamp in northern France on 21 August 1944. (10)

The centre section of Biber No.90 looking forward showing one of the batteries in place. Image © IWM (A 27777)

The German submarine was built in three sections – the forward buoyancy tank, the crew compartment and the rear section that contained both the power plant and the rear buoyancy tank. The sections were bolted together with watertight seals to protect the operator. It was armed with either mines or G7e electric powered torpedoes – which it could only fire once on the surface.

Although designed to be easy to operate, the pilots – many from non-naval units like the SS – needed to be trained and although the programme was designed to be some eight weeks long, the initial group of submariners were trained in just three weeks.

Within the submarine everything was reduced to a bare minimum.

A view of the sail or conning tower of Langdorff’s submarine after it had been raised from Dover Harbour. Note the compass projector, periscope and snorkel air intake masts. The size of the entry hatch is approximately 18 inches (45 centimetres) in diameter with the scuttle or ‘window’ being around 15 inches or 35 centimetres. Image © IWM (A 28253)

With only a single crewman and operations lasting up to two days, handling the submarine and conditions aboard could be very difficult. With no trimming tanks and diving planes manoeuvring underwater was difficult. Because of its small size it was a ‘fair weather’ boat – able to operate only in relative calm waters.

A technical evaluation report in the IWM Archives on the Biber submarine dated 27 March 1946 (11) contains a detailed summary of the submarine’s technical capability.

The small conning tower was made of aluminium and projected 15 inches (381mm) above the hull. The vessel was entered through a circular hatch with a glass scuttle (window) in the top. This was secured by three simple hand clips and a rubber seal. The tower also had a small running light.

Although there was a magnetic compass mounted in a bowl near the periscope, it was found that this was not steady enough for accurate navigation, as the compass was affected by movement of the hull.

The 4 foot 6 inch (1.2 metre) periscope had a fixed magnification of 1.5 times and was clear – at least when dived – and was fitted with cross hairs and a bearing indicator to enable torpedo attacks to be launched.

However the periscope could only be turned to see about a quarter of the horizon.

The pilot had to be awake throughout the mission and had a special chocolate ration fortified with caffeine and other stimulants as well as an experimental drug known as D1-X (12) (13)

Some pilots suffered from claustrophobia, some from violent sea-sickness and of course there were no ‘heads’ aboard meaning that all bodily waste had to be disposed of overboard when – and if – possible.

The rear compartment of a captured ‘Biber’ showing the Opel vehicle petrol engine. Image © IWM (A 27775)

But the real problem was the choice of the main power plant. Submarines at this time made extensive use of diesel engines for surface running with a battery-driven 13 horse-power electric motor for manoeuvring beneath the waves.

The Biber used the readily available and proven petrol engine from an Opel ‘Blitz’ lorry to propel the boat on the surface and to charge the electric motor’s batteries.

The main engine not only heated the crew compartment but also gave off poisonous carbon monoxide gas – so much so that running the engine for 45 minutes or more built up dangerous levels of the gas.

Pilots were equipped with oxygen apparatus but this supply only lasted for twenty hours – often less than half of that of a typical mission.

The rear of the Biber No.90’s conning tower with the cracked rear armoured scuttle. Note what appears to be a hole in the pipe on the right of the image (to the right of the hair on the original negative) as well as possible heat damage forward of the pipe’s connection to the large dark shape in the centre of the image.  Many of the original parts were redesigned and fabricated in Royal Navy workshops to enable the submarine to be tested safely. A report on these tests found that the Biber class of vessels were succumbing to ‘numerous defects’ as ‘the direct result of poor material or detail in design’. It went on to conclude that ‘There is no doubt that the Biber is a layout and production of very low calibre and must be intended as a “one-shot” weapon’. Image © IWM (A 28254)


Although the cause of Langsdoff’s death can be explained, there is still a mystery surrounding a message in a bottle found under his seat.

An ‘official report’  (since lost) apparently states that there was ‘a bottle hidden under the seat and inside was a document in English which, romantic as it read, appeared to have some bearing upon the capture of the submarine and possibly the explanation of why the pilot met his end’. (14)

Because of this, there is speculation that suicide may have played a part in Langsdoff’s death. (15)

Langsdorff’s submarine on display prior to the Imperial War Museum reopening to visitors after the Second World War in November 1946. Note that the periscope assembly is not fitted to the submarine. Although the hull of Biber 90 was transferred to Imperial War Museum in April 1946, the periscope assembly was not sent to the museum until September of that year. Image © IWM (D 29422)

Biber no. 90 submarine with masts fitted and a single G7E 21 inch (53 cm) electric torpedo as fitted when the vessel was first captured. Although the submarine is no longer at IWM London an example of the torpedo can be found in the Second World War gallery. Image © IWM (MAR 558). Original Source:



(1) – retrieved 10 September 2017

(2) ‘The German Biber Submarine’ by James Bullen, Imperial War Museum Review No. 4 (pages 79-86) Published by The Trustees of the Imperial War Museum (1989). ISBN 0-901627-5-26

(3) – retrieved 10 September 2017

 (4) German Midget Submarine – Biber type, Report of trials carried out on Clyde area; risk to personnel prohibits completion of trials. Report dated 25 April 1945 detailing a petrol vapour explosion that occurred on 22 April.

Following a previous breakdown the submarine had been repaired and Halliday was sitting in the vessel. He had operated the engine starter when an electrical spark caused the explosion that damaged his clothing and caused him to receive minor burns to his face and head. Another man Able Seaman Hastings who was standing nearby also received minor flash burns to his face.

According to the same report Halliday was expected to be off duty for about a week while Hastings returned to duty the nexy day.

File reference: ADM 1/18151, UK National Archives. File consulted 7 September 2017.

(5) Private papers of Lieutenant Commander A C Halliday RN. IWM Catalogue reference: Documents 1460 – consulted 18 September 2017.

(6) – retrieved 10 September 2017.

(7) – retrieved 10 September 2017.

(8) – retrieved 10 September 2017.

(9) – retrieved 10 September 2017.

(10) – retrieved 10 September 2017.

(11)Private papers of Lieutenant Commander A C Halliday RN. Op. cit.

(12) – retrieved 11 September 2017.

(13)  – retrieved 8 January 2018.

(14) – retrieved 11 September 2017.

(15) – post 22. Retrieved 10 September 2017.



The IWM Sound Archives contains an oral interview with Klaus Rudolf Georg Goetsch who served aboard the heavy cruiser KMS Prinz Eugen in 1943 before transferring to the Kleinkampverbande in 1944.

Image of the main Biber controls: – retrieved 8 January 2018

A variety of Biber submarines are preserved. See the links below for details: – retrieved 8 January 2018 – retrieved 8 January 2018– retrieved 8 January 2018– retrieved 8 January 2018 – retrieved 8 January 2018

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