E-boat

This design was chosen because the theatre of operations of such boats was expected to be the North Sea, English Channel and the Western Approaches. The requirement for good performance in rough seas dictated the use of a round-bottomed displacement hull rather than the flat-bottomed planing hull that was more usual for small, high-speed boats. The shipbuilding company Lürssen overcame many of the disadvantages of such a hull and, with the Oheka II, produced a craft that was fast, strong and seaworthy. This attracted the interest of the Reichsmarine, which in 1929 ordered a similar boat but fitted with two torpedo tubes. This became the S-1, and was the basis for all subsequent E-boats.

After experimenting with the S-1, the Germans made several improvements to the design. Small rudders added on either side of the main rudder could be angled outboard to 30 degrees, creating at high speed what is known as the Lürssen Effect.[8] This drew in an "air pocket slightly behind the three propellers, increasing their efficiency, reducing the stern wave and keeping the boat at a nearly horizontal attitude".[9] This was an important innovation as the horizontal attitude lifted the stern, allowing even greater speed, and the reduced stern wave made E-boats harder to see, especially at night.

E boats were primarily used to patrol the Baltic Sea and the English Channel in order to intercept shipping heading for the English ports in the south and east. As such, they were up against Royal Navy and Commonwealth, e.g., Royal Canadian Navy contingents leading up to D-Day, motor gunboats (MGBs), motor torpedo boats (MTBs), motor launches, frigates and destroyers. They were also transferred in small numbers to the Mediterranean, and the Black Sea by river and land transport. Some small E-boats were built as boats for carrying by auxiliary cruisers.

Crew members could earn an award particular to their work—Das Schnellbootkriegsabzeichen—denoted by a badge depicting an E-boat passing through a wreath. The criteria were good conduct, distinction in action, and participating in at least twelve enemy actions. It was also awarded for particularly successful missions, displays of leadership or being killed in action. It could be awarded under special circumstances, such as when another decoration was not suitable.

Schnellboot S-1

E-boats of the 6th & 9th flotillas from Cherbourg attacked Exercise Tiger on 28 April 1944, causing about 749 American Army and Navy casualties.

E-boats of the 9th flotilla were the first naval units to respond to the invasion fleet of Operation Overlord.[10] They left Cherbourg harbour at 5 a.m. on 6 June 1944.[10] On finding themselves confronted by the entire invasion fleet, they fired their torpedoes at maximum range and returned to Cherbourg.[10]

During World War II, E-boats claimed 101 merchant ships totalling 214,728 tons.[11] Additional claims include 12 destroyers, 11 minesweepers, eight landing ships, six MTBs, one torpedo boat, one minelayer, one submarine, and a number of smaller craft such as fishing boats. They also damaged two cruisers, five destroyers, three landing ships, one repair ship, one naval tug, and numerous other merchant vessels. Sea mines laid by the E-boats sank 37 merchant ships totalling 148,535 tons, a destroyer, two minesweepers, and four landing ships.[11]

E-boat crews were awarded 23 Knight's Cross of the Iron Crosses and 112 German Crosses in Gold.[11]

To boost Axis naval strength in the Black Sea, the OKW ordered to the region the transfer of six E-boats of the 1st S-flotilla, the last to be released from action in the Baltic Sea before refit. The Romanian port of Constanța, in the Black Sea, was chosen as the S-flotilla's headquarters. Transporting the six boats overland from Germany to Romania was an impressive logistical feat. The superstructure and all weapons were removed, leaving only the hull. After a long road journey of 60 hours, the boats arrived at Ingolstadt, where they were transferred back to water and towed towards Linz.[12] Upon reaching the Austrian city, the superstructure was rebuilt, then the journey continued down the Danube to Galați, where the main engines were installed. The E-boats then continued on their own power towards Constanța, where refitting was completed.

The first two boats, S-26 and S-28, arrived in Constanța on 24 May 1942, the second pair, S-72 and S-102 on 3 June, and the final pair, S-27 and S-40 10 days later.[13] After the sinking of S-27 by a malfunctioning torpedo, four more reserve boats, S-47, S-49, S-51, S-52 were dispatched to the Black Sea, in order to replace boats undergoing maintenance.[14] S-28, S-72 and S-102 were soon relegated to the Constanța Shipyard for engine replacement, leaving only S-26 and the newly commissioned S-49 operational.[15] On 1 January 1944, the 1st S-flotilla numbered six operational boats: S-26, S-42, S-47, S-49, S-52 and S-79 while S-28, S-40, S-45 and S-51 were all out of commission, undergoing repair in Constanța. Three more boats were shipped down the Danube and were being reconstructed at Constanța.[16] On 1 June 1944, 8 boats were operational in Constanța: S-28, S-40, S-47, S-49, S-72, S-131, S-148 and S-149. The boats were however penned in harbor, due to fuel shortage. During July, S-26, S-28, S-40 and S-42 were transferred to Sulina at the mouth of the Danube, where S-42 was fitted with a new propeller. They were joined by S-72 in early August, the rest of the boats remaining in Constanța. On 19 August, S-26, S-40 and S-72 were destroyed in port by a Soviet air attack. On 22 August S-148 hit a mine and sank near Sulina, and on the following day, S-42, S-52 and S-131 were destroyed in Constanța by a Soviet air attack.[17] What remained of the S-flotilla was disbanded after Romania switched sides on the same day.[18]

Italian MS 472, post-war configuration

The poor seaworthiness of the Italian-designed MAS boats of World War I and early World War II led its navy to build its own version of E-boats, the CRDA 60 t type, classed MS (Motosilurante). The prototype was designed on the pattern of six German-built E-boats captured from the Yugoslav Navy in 1941. Two of them sank the British light cruiser HMS Manchester in August 1942, the largest warship to be sunk by fast torpedo craft in the Second World War.[19] After the war these boats served with the Italian Navy, some well into the 1970s.[20]

The Kriegsmarine supplied the Spanish Francoist Navy with six E-boats during the Spanish Civil War, and six more during the Second World War. Another six were built in Spain with some assistance from Lürssen. A motor boat of the early series, either the Falange or the Requeté, laid two mines off Almería that crippled the British destroyer HMS Hunter on 13 May 1937. The German-built boats were discarded in the 1960s, while some of the Spanish-built ones served until the early 1970s.[21]

This is one of the S-7-class boats, S-13. The Chinese Navy operated three boats of this class.

The Chinese Nationalist Navy had three S-7-class boats during the Second Sino-Japanese War.

• Yue-22 (岳-22)
• Yue-253 (岳-253)
• Yue-371 (岳-371)

Yue-22 was destroyed by Japanese planes, Yue-371 was sunk by its sailors to avoid being captured by the Japanese soldiers and Yue-253 was captured by the People's Liberation Army during the Chinese Civil War. Yue-253 was renamed "Hoiking" (海鯨), meaning "Seawhale" in Chinese. The People's Liberation Army Navy used it as a patrol boat until 1963.

The Chinese Nationalist government also ordered eight S-30-class E-boats and a tender, Qi Jiguang (戚繼光). These were taken over by the Kriegsmarine in 1939. Qi Jiguang was renamed Tanga.

Germany sold four E-boats to Romania on 14 August 1944.[22] These vessels displaced 65 tons, had a top speed of 30 knots generated by three Mercedes-Benz engines totalling 2,130 kW (2,850 hp) and were armed with two 500 mm (20 in) torpedo tubes. Each of the four boats had a crew of 25. They were numbered 10 to 13 (formerly S-151, S-152, S-153 and S-154) and served in the Romanian Navy until at least 1954.[23]

At the end of the war about 34 E-boats were surrendered to the British. Three boats, S-130 (renamed P5230), S-208 (P5208) and S-212 (P5212) were retained for trials.

The Gehlen Organization, an intelligence agency established by American occupation authorities in Germany in 1946 and manned by former members of the Wehrmacht's Fremde Heere Ost (Foreign Armies East), used Royal Navy's E-boats in order to infiltrate its agents into the Baltic states and Poland.[24] Royal Navy Commander Anthony Courtney was struck by the potential capabilities of former E-boat hulls, and John Harvey-Jones of the Naval Intelligence Division was put in charge of the project. He discovered that the Royal Navy still had two E-boats, P5230 and P5208, and had them sent to Portsmouth, where one of them, P5230 (ex-S130), was modified to reduce its weight and increase its power with the installation of two Napier Deltic engines of 1,900 kW (2,500 hp) each.[25]

Lieutenant-Commander Hans-Helmut Klose was assigned to command a German crew, recruited by the British MI-6 and funded by the American Office of Policy Coordination. The missions were assigned the codename "Operation Jungle". The boats carried out their missions under the cover of the British Control Commission's Fishery Protection Service, which was responsible for preventing Soviet navy vessels from interfering with German fishing boats and for destroying stray mines. The home port of the boats was Kiel, and operated under the supervision of Harvey-Jones. Manned by Klose and his crew, they usually departed for the island of Bornholm waving the White Ensign, where they would hoist the Swedish flag for a dash to Gotland, and there they would wait for orders from Hamburg. The first mission consisted in the landing of Lithuanian agents at Palanga, Lithuania, in May 1949,[26] and the last one took place in April 1955 in Saaremaa, Estonia.[27] During the last two years of the operation, three new German-built motorboats replaced the old E-boats.[28] Klose was later assigned the command of a patrol boat in the Bundesmarine and became commander-in-chief of the fleet before his retirement in 1978.[27]

In 1947, the Danish navy bought twelve former Kriegsmarine boats. These were further augmented in 1951 by six units bought from the Royal Norwegian Navy. The last unit, the P568 Viben, was retired in 1965.[29]

After World War II, the Norwegian Navy received a number of former Kriegsmarine boats. Six boats were transferred to Denmark in 1951.