U-573 The Spanish U-boat (photos from Cartagena added 09/07/2024)

The Spanish U-boat

Submarine G-7 (formally U-573) docked at Barcelona

The U-573 was a Type VIIC U-boat. Her keel was laid down 8 June 1940 at the Blohm & Voss yard in Hamburg. She was launched on 17 April 1941 and commissioned 5 June with Captain Heinrich Heinsohn (12 February 1910 – 6 May 1943) in command. Heinsohn commanded her for her entire career in the Kriegsmarine. In May 1941 he had arranged that the city of  Landeck in Tyrol adopted the submarine within the then popular sponsorship programme (Patenschaftsprogramm), organising gifts and holidays for the crew, earning her the honorary name "U-573 Landeck".

Badge of the U-573 Landeck

U-573 had a displacement of 769 tonnes. She had a total length of 67.10 m, a beam of 6.20 m, a height of 9.60 m and a draught of 4.74 m. The submarine was powered by two Germaniawerft F46 four-stroke, six-cylinder supercharged diesel engines producing a total of 2,800 to 3,200 metric horsepower for use while surfaced, two Brown, Boveri & Cie GG UB 720/8 electric motors producing a total of 750 metric horsepower for use while submerged. She had two shafts and two 1.23 m propellers. The boat was capable of operating at depths of up to 230 metres.

The submarine had a maximum surface speed of 17.7 knots and a maximum submerged speed of 7.6 knots. When submerged, the boat could operate for 80 nautical miles at 4 knots; when surfaced, she could travel 8,500 nautical miles at 10 knots. U-573 was fitted with five 53.3 cm (21 in) torpedo tubes (four in the bow and one at the stern), fourteen torpedoes, one 8.8cm SK C/35 naval gun, 220 rounds, and a 2cm C/30 anti-aircraft gun. The boat had a crew complement of between forty-four and sixty.

The boat began her service career as part of the 3rd U-boat Flotilla when she conducted training; on 1 September 1941 she commenced operations with that flotilla. She was transferred to the 29th Flotilla, also for operations, on 1 January 1942. She was sold to the Spanish Navy that same year and became the Spanish submarine G-7.

U-573 (renamed G-7) in Spanish service

Combat History during WW2

Her operational career began with her departure from Kiel on 15 September 1941. She entered the Atlantic via the North Sea and the gap between Iceland and the Faroe Islands. She almost reached the Labrador coast before heading for St. Nazaire in occupied France, docking on 15 November.

U-573's second patrol involved the boat slipping past the heavily defended Strait of Gibralter into the Mediterranean, where she sank the Norwegian Hellen (5,289 GRT) with two torpedoes on 21 December 1941 (the boats only kill during her service). She arrived at Pola in Croatia on 30 December.

Her third sortie was relatively uneventful, starting and finishing in Pola between 2 February and 6 March 1942.

During her fourth and final patrol, on 1 May 1942 at approximately 15.56 hrs, 40 miles north-west of Ténès, Algeria, a British Hudson bomber AM735 (RAF Sqdn 233/M, pilot: Sgt Brent) on patrol from Gibraltar dropped three 250lb depth charges on the boat. Two were seen to explode very close on the starboard side aft, lifting the stern out of the water as the boat dived. U-573 was then seen to resurface close to a large patch of oil with about ten men standing on the bridge and raising their hands in surrender. The pilot felt it was not justified to strafe the U-boat as the crew did not man the AA guns, but the assessment of Coastal Command was that he should have machine-gunned the crew because there were no surface vessels nearby to accept the surrender. The aircraft circled the area until it was low on fuel, returning to base at 16.20 hrs.

U-573 was left severely damaged, with one electric motor and both diesel engines out of order, both batteries damaged, leaks in the diving and ballast tanks on the starboard side and a large dent in the pressure hull at the stern. On receiving a distress call from U-573, the FdU ordered the nearby U-74 and U-375 to assist, and Italian submarines Emo and Mocenigo also joined the rescue operation. The Allies sent aircraft from Gibraltar and detached HMS Wishart and HMS Wrestler from a group of five destroyers on A/S patrol east of Gibraltar to intercept the crippled U-boat. The commander of U-573 at first thought he would have to scuttle the boat, but the engineers managed to restart one of the electric motors to move slowly northwards. The radio was also initially out of action, and U-573 was unable to report her position to rendezvous with her rescuers. On the morning of the 2nd May, SKL ordered her to proceed to Cartagena in neutral Spain, where U-573 arrived at 11.36 hrs. Allied forces searching for U-573 located and sank U-74 shortly afterwards.

International agreements allowed ships in neutral ports 24 hours to make emergency repairs before they were to be interned. The Spanish authorities granted U-573 a three-month period for repairs, which prompted several strong protests from the British Embassy in Madrid. On 19 May Heinsohn flew from Madrid to Stuttgart, then travelled on to Berlin, in order to discuss the situation with the Kriegsmarine. He returned by train via Hendaye (in southwest France) on 28 May. Realizing that even three months would not be enough to repair the boat, the Kriegsmarine sold the vessel to Spain for 1.5 million Reich Marks. On 2 August 1942, at 10 am, (one day before the three-month period was due to expire), the Spanish navy commissioned the boat as the G-7.

U-573's crew were interned in Cartagena and were gradually released in groups of two or three. The last five members of the crew left with Captain Heinsohn on 13 February 1943. He returned to Gotenhafen (now Gdynia, Poland). In March he was ordered to Brest, to take command of U-438, and died with all his crew on 6 May 1943.

Spanish Service

G-7 being repaired at Cartagena

Work started on the U-573, now the G-7, began in August 1943 following the sale to Spain but took four years to complete. The damage caused by the British attack was found to be more extensive than was first thought; also German technical assistance and parts were difficult to obtain in the last years of World War II and indeed after the war in Europe had ended! In addition, Spain's economy was weak following the Civil War. Finally repairs were completed in early 1947 and on 5 November 1947 G-7 was re-commissioned. The bow's net cutter and the 20mm anti-aircraft cannon were removed.

Despite the Type VII being out-dated by the end of World War II, G-7 was the most modern of Spain's submarine fleet; her other vessels (two ex-Italian, and four home-built boats) dating from the early 1930s. G-7 lacked radar and did not possess a snorkel.

G-7 here photographed after she was renamed S-01 in 1961

In 1958 Arca-Filmproduktion GmbH rented G-7 to take part in the semi-fictitious movie U-47 Kapitanleutnant Prien partially based on his patrol to Scapa Flow, where he sank HMS Royal Oak.

In 1961 the Spanish Navy's submarine force was re-numbered, and G-7 became S-01.

On 2 May 1970 she was de-commissioned after 23 years service. She was auctioned for 3,334,751 Pts (about 26,500 US Dollars), after which, despite efforts to save and preserve her as a museum, the submarine was broken up for scrap.

Submarine exhibition, Cartagena Naval Museum

Back in May we visited the excellent Spanish Naval Museum at Cartagena

One Spanish Submarine was covered in some detail, the famous Spanish U-boat - U573  

1/56 scale model showing internal detail

The Submarine`s badge note the two Spanish designations G-7 and S-01

The sub`s deck gun which used to be displayed out on the harbour front

Additional information

One other U-Boat was interned by the Spanish during WW2 - U-760.

On 8 September 1943, about 150 nautical miles off Cape Finisterre, U-760 was sailing on the surface alongside U-262 when they were attacked by Allied aircraft. U-760 fled into Vigo harbour and surrendered to the Spanish cruiser Navarra. Under International neutrality agreements allowed ships to spend up to 24 hours in neutral harbours to make emergency repairs, but U-760 was unable to get underway in time. She was interned at Ferrol for the remainder of World War II. The submarine engine was dismantled and used to generate electric energy for the city of Vigo's tram network. On 23 July 1945, the boat was taken to the United Kingdom for Operation Deadlight and was scuttled on 13 December 1945.