British Coastal Forces - Two World Wars and After

Norman Friedman has published an expanding series of impressive in-depth volumes covering British warships in the twentieth century which complement his eight-volume series on American warships in that century. This latest addition to the British series covers coastal forces and embraces the motor launches and coastal motor boats of the First World War and the motor torpedo boats, motor gunboats, steam gunboats and motor launches of the Second World War. It also takes in the RAF’s air sea rescue launches, which were similar to the fast attack boats, and the post war coastal forces. Three classes of coastal motor boats (CMB), the first motor torpedo boats, were built in the First World War to Thornycroft designs. The 40-foot boat carried one torpedo, while the 55-foot version carried two. Their stepped planing hull had been developed by Thornycroft before the war in a series of hydroplanes culminating in Miranda IV which reached a speed of 35 knots. The idea to adopt this hull for a torpedo boat originated in the summer of 1915 when three lieutenants in the Harwich Force suggested a fast hit-and run boat capable of skimming over minefields and attacking German surface shipping in the Heligoland Bight. Thornycroft responded with the 40-foot design, with double and, below the waterline, triple mahogany planking, and 39 boats were completed. The torpedo was carried pointing forward in a trough on the stern and was launched by being pushed along rails and over the transom by a steel ram powered by expanding cordite gases. The boat, with a speed roughly equal to that of the torpedo, had to swiftly turn out of the way. Later the 55-foot version was added (73 boats), and finally the 70-foot minelaying type (five boats). Their two main bases were Osea Island on the River Blackwater and Dunkirk, and their main operations were off the Belgian and Dutch coasts. Their first success came in April 1917 when four CMBs attacked German destroyers off Zeebrugge and sank one of them. In the spring of 1918 CMBs played a major part in the Royal Navy’s attempt to block the harbours of Zeebrugge and Ostend, laying down smoke to cover the approach of the blockships, marking the harbour entrances with flares and attacking German ships and gun positions. Fifteen CMBs were lost in the war: the greatest threat came from aircraft. In August 1918 six 40-foot boats were caught by German seaplanes off the Dutch coast and, in a long battle, three were sunk and the other three driven into Dutch waters where they were interned. In 1919 and 1920 CMBs were used in operations to support the White Russians in the north (Dvina River), the Baltic and in the Caspian Sea (to where 40-foot boats were transported overland), during the Russian civil war. The 40-foot CMB 4 (Lieutenant Augustus Agar) sank the Russian cruiser Oleg off Kronstadt in June 1919. Two months later CMB 4 and six of the 55-foot boats raided the base at Kronstadt, torpedoing and heavily damaging a Russian pre-Dreadnought battleship and sinking a submarine depot ship. Here Friedman gets some of the details wrong, asserting that two battleships were sunk in addition to the depot ship. After the war coastal forces were wound down because the main threat was perceived to be war with Japan, but by 1936, with the increasing prospect of war in Europe, the Royal Navy was again investing tentatively in coastal forces and a number of motor torpedo boats (MTBs) were built by the British Power Boat Co. (BPB) at Hythe, on Southampton Water. Vosper, at Portsmouth, responded by building, as a speculative venture, an experimental MTB of 68-foot length, which, before being armed, achieved 48 knots on trials. Once fully armed and loaded she achieved 44 knots and proved her seaworthiness in winds of Force 7. This led to her being purchased by the Admiralty as MTB 102 and signalled the start of the extensive programme of MTB development and construction by Vosper during the Second World War. The Admiralty ordered some 75 Vosper 70-foot MTBs in 1939 and 1940 as the German occupation of Europe and the threat of invasion exacerbated the need for such craft. A further 16 were ordered in 1942, followed in 1943 and 1944 by 28 of the slightly larger and improved 73-foot design. Meanwhile BPB concentrated on motor gunboats (MGBs) and built 113, mostly 70-and 72-foot, some of which were completed as MTBs. Some boats were built in America and Canada to Vosper and BPB designs respectively, whilst White and Thornycroft also contributed a few boats of their own designs. In service, the boats were used to attack German coastal convoys at night and to lay mines. To counter German E-boats it was thought that larger, more heavily armed boats were needed, leading to the steam gunboats and the ‘long’ MGBs (of the Fairmile D and Camper & Nicholsons types). These had a longer range than the short boats but were slower and, in the case of the Fairmile Ds, less sturdy, and were met with less than universal approval by coastal forces commanders. The fast attack craft of the short and long types served in both home and Mediterranean waters and, with the motor launches, played an important part in the Normandy invasion. By mid-1945 coastal forces (including motor launches) claimed a total of 503 enemy vessels sunk, probably sunk, destroyed, or captured. This figure does not include the many midget submarines captured or destroyed, nor vessels sunk as a result of the extensive minelaying activities of the coastal forces. After this war coastal forces were again run down but a core fleet of two operational squadrons was maintained, with many more boats in reserve, mostly unmaintained. The Korean war led to orders for new boats of the Gay and Dark classes and some of the war-bult reserve boats were refitted. Trials with gas turbine-engined fast patrol boats were also underway. However, the 1957 defence review concluded that in a ‘limited’ war with the USSR they would be of little use despite the protestations of the Navy that they could seal off the Baltic. The new post-war craft were paid off and only a small trials and training unit of three boats was retained. Finally, in 1970, three fast training boats of the Scimitar class were built for use in anti-patrol boat training and the Vosper demonstration boat Tenacity was purchased, all serving until the early eighties. Friedman hits his usual high standard. Whilst the emphasis is on the technical aspects of the boats’ design and development, this is skilfully combined with summaries of the operational tactics and patrols. Throughout, the book is both detailed and analytical, and relies on extensive research in the primary source archives as well as authoritative secondary sources. It is profusely illustrated with monochrome images accompanied by informative, often extended, captions, as well as plans. There are comprehensive data lists covering all the craft in the appendices. This is undoubtedly an important, major work and, despite a few minor errors (which are surely inevitable in book of this size and scope), will serve as a seminal work on the subject.

Sometimes called the “mosquitoes of the sea”, coastal forces have always enjoyed an image of dash, verve and unconventional leadership, but this belies a highly professional and brave force. Norman Friedman opens his review of British coastal forces in both wars with a succinct chapter covering administration, operational experience in both world wars and the steady decline of RN Coastal Forces post-war. WW1 saw the RN using US built motor launches primarily for ASW patrol, including being armed with hand dropped depth charges! The CMBs were the first offensive coastal forces craft with a “tail first” torpedo fired from the stern, and by the end of the war the Admiralty was convinced of the value of small attack craft, reinforced in 1919 by Agar’s VC winning attack on the Bolshevik ships at Kronstadt. Post WW1 coastal forces were low priority but by the late 1930s the competition between the British Power Boat company and Vospers was resulting in new designs for MTBs and MGBs. At the start of WWII the Admiralty was still not convinced that MTBs “were worth what they cost”, operationally constrained in daylight and bad weather, with limited endurance and maintenance intensive. However, the German occupation of Europe and threat of invasion gave new impetus to coastal forces. The book traces the development of the wartime MTBs with enhanced weapons, radar and communications; the 70ft lightly armed MTB of 1940 evolved into the heavily armed 110ft Fairmile “Dog” boats, both MTB and MGB. The wartime MGBs were tasked with dealing with the E-boat threat. As Friedman says, the workhorse MLs saw “considerable action” not least on the St Nazaire raid of 1942. Whilst the book primarily focuses on the evolution of coastal forces craft, those manning the MTBs and MGBs are given proper recognition. Fighting a thin skinned wooden boat in the dark with no modern navigation aids, sitting on top of some 1700 gallons of petrol, was not for the faint hearted. Predominantly officered by RNVR officers, their courage is epitomised by the exploits of MGB legend Robert Hichens. This book has all the hallmarks of Norman Friedman‘s previous books on British warship classes -exhaustive research, comprehensive informative text and well-captioned, fascinating photos. The book isn’t cheap but it really is the “complete” story of RN Coastal Forces from the CMB to the final days of the Scimitar Class. As I have remarked in reviewing some of Friedman’s previous books, this is not a book to read in one go but to be enjoyed in quiet study. Very highly recommended.