Armament varied and some S26 class boats substituted a 40mm Bofors or, less commonly, a 20mm flakvierling (quadruple mount) for the aft 37mm cannon.

[6] As a result of early war experience of combat against the fast and powerful S-boats, the Royal Navy created its MGB force and later developed better-matched MTBs, using the Fairmile 'D' hull design.

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 shipbuilding company Lürssen at Vegesack, Bremen, overcame many of the disadvantages of such a hull and, with the private motor yacht Oheka II in 1926, produced a craft that was fast, strong and seaworthy.

[7] 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".

Its length was generally divided by eight transverse bulkheads (made of 4mm steel below the waterline and slightly thinner light metal alloy above) into nine watertight compartments.

[10] From bow to stern, these were: Note that the earliest (shorter) boats lacked the first transverse bulkhead, and thus the senior ratings' accommodation was included in the first watertight compartment.

Each flotilla required the backup of a depot ship; initially this was provided by the converted steamer Nordsea, but from 1934 a series of purpose-built tenders were commissioned - the Tsingtau in 1934, followed by the Tanga (in 1939), Carl Peters and Adolf Lüderitz in 1940, and finally the Herman von Wissmamm and Gustav Nachtigal.

[14] Upon reaching the Austrian city, the superstructure was rebuilt, then the journey continued down the Danube to Galați, where the main engines were installed.

Kajmakcalan and Durmitor escaped to Alexandria in April 1941 to join the Allies; the other six fell into Italian hands and became Ms41 to Ms46, four of them eventually captured by the Germans and refitted with standard 533 mm torpedoes (see below under "S2 class").

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.

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.

[24] 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 (19.685 in) torpedo tubes.

[citation needed] 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 the Royal Navy's E-boats in order to infiltrate its agents into the Baltic states and Poland.

[26] 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.

[27] Lieutenant-Commander Hans-Helmut Klose [de] was assigned to command a German crew, recruited by the British MI6 and funded by the American Office of Policy Coordination.

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.

Serving initially in the Unterwasserwaffenschule training sailors in underwater weaponry such as mines and torpedoes, she later became a test boat under the name EF 3.

[citation needed] S130 was purchased and towed from Wilhelmshaven to the Husbands Shipyard, Marchwood, Southampton, England in January 2003, under the auspices of the British Military Powerboat Trust.

In 2004, S130 was taken to the slipway at Hythe, where, under the supervision of the BMPT, she was prepared and then towed to Mashfords yard in Cremyll, Cornwall, England to await funding for restoration.

In 2008, S130, having been purchased by the Wheatcroft Collection, was set up ashore at Southdown in Cornwall to undergo restoration work involving Roving Commissions Ltd.

Although commissioned in 1939, its petrol engines gave frequent problems, and on 10 September 1940 its stern was rammed (by S13) in Vlissingen, and was later removed from active service.

Eight petrol-engined boats similar to the original S2 class had been ordered from Lürssen, Vegesack, and completed in 1937-39 for that navy as Orjen, Durmitor, Suvobor, Kajmakcalan, Velebit, Dinaira, Rudnik and Triglav.

When Italy occupied Yugoslavia in April 1941, two of them (Durmitor and Kajmakcalan) escaped to Alexandria and served with the Allied forces, while the other six were commissioned into the Italian Navy as Ms41 to Ms46.

They were originally ordered on 9 August (a week after S26 to S29) for the Chinese (Nationalist) Navy (the last two initially from Naglo, Berlin, but the contract was later switched to Lürssen), and were sequestered for use by the Kriegsmarine.

S67 introduced an improved design with a partially armour-plated cupola (the Kalotte or skull cap) over the bridge, providing protection from weather as well as small arms fire, with a lower profile.

Originally the Germans planned to sell these to Bulgaria, and they were formed as the new 7th S-flotilla in October 1941, but the Kriegsmarine's need for them in the Mediterranean had caused them to be sent south via the French inland waterways.

A class of small fast attack craft designed as offensive mine-layers (rated Küstenminenleger), able to carry up to 4 mines, and to operate close to enemy shores.

21 boats were equipped with 2 x 450mm fixed stern torpedo tubes replkacing the mines, and were reclassed as KS-boats (Kleinst Schnellboote), retaining their original numbers but replacing the "KM" prefix by "KS".