Light Coastal Forces was a branch of the Royal Navy, formally established in late 1940 during the early period of the Second World War, in response to an emerging threat from the German Navy, known at that time as the Kriegsmarine.
Its distinctiveness as a unit lay not just in its use of motor boats—which included some of the fastest sea-going craft of their day—nor in its varied roles or methods of operation, but in the men who crewed the boats; men who were mostly drawn from civilian life, either as reservists or as volunteers, and who served for the period of ‘hostilities only’ before being discharged back to ‘civvy street’.
The motor boats or ‘little ships’ as they were affectionately known by their crews, were in sharp contrast—in terms of scale—to the regular ‘big ship’ navy of major warships, and the close camaraderie enjoyed by the men of these tight-knit fighting units was to prove a defining characteristic of Coastal Forces.
Though no distinct branch named Coastal Forces existed during the earlier 1914–1918 conflict, the large scale use and deployment of purpose-built fast motor boats began at this time.
During the First World War the unrestricted use of submarine and mine warfare constituted a grave threat to shipping, particularly in the English Channel, where millions of men and their supplies were required to be transported by sea to France throughout the period of the war.
In response to the growing menace posed by these modern forms of warfare, an irregular assortment of boats including private yachts were drafted into service in support of the regular navy as part of the Auxiliary Patrol, before more effective solutions to tasks such as submarine chasing were sought in the form of purpose-built motor launches built by the American company Elco.
A force of some five hundred and eighty of these motor launches were built by Elco, augmented by faster boats called Coastal Motor Boats (CMBs). The CMBs were designed and built by the British manufacturer Thornycroft to carry torpedoes as part of an offensive capability. The use of motor boats on this scale mostly crewed by reservists served as a blueprint for the later Coastal Forces.
Following the defeat of Germany in 1918 and the signing of an Armistice which expressly forbad Germany the “construction or acquisition of any submarine”, most of the Motor Launches and Coastal Motor Boats together with the knowledge and experience their crews had acquired during that period were disposed of, in favour of a peace dividend, and the focusing by senior officers once more on capital ships.
Though the experience of the officers and men passed into and was held in the reserves, and although manufacturers such as Vosper and British Power Boat continued to evolve the design of fast motor boats in a non-military context for private buyers; momentum in development of the military use of such boats, together with the organisational know-how required for their use, was effectively lost at this point.
The Admiralty did not look again at the concept of the fast motor boat until the 1930s, when the prospect of war with Germany and Japan, in what they considered would be the following decade, looked increasingly likely. They began to weigh up designs for a new generation of motor torpedo boat from power boat manufacturers of the day such as British Power Boat under Hubert Scott-Paine, and Vosper under Peter Du Cane.
The slow pace of development however did not see any new boats commissioned until 1936, and although the Admiralty may have signalled their intent to rebuild forces in the long-term, military marine development during this period lagged behind the evolution in aeronautical design of fighter aircraft such as the Spitfire, whilst training for navy personnel in the tactical use of fast motor boats, and overall command & control structures, were poor or non-existent.
This comparative neglect of fast motor boat capability was to be lamented by some involved in their later use during the Second World War, who faced an uphill struggle at that time to re-establish the kind of training & support network needed to tend to such high-maintenance craft.
Those involved in the early formation of Coastal Forces were to find themselves doing battle at sea in boats that proved underpowered and poorly armed, in comparison to an enemy whose boats had enjoyed continuous development throughout the decade leading to war.
The German Schnellboot or E-boat which the early motor torpedo and gunboats encountered were faster and more heavily armed, and showed better seakeeping qualities in rough seas. They also derived the benefit of high-speed marine diesel engines which proved safer in operational use than the highly flammable petrol engines fitted to most British designed boats.
Within less than a year of the start of war, German forces achieved objectives they had failed to accomplish throughout years of bitter fighting during the previous conflict—the complete overthrow of France, Belgium, and the Netherlands.
At a stroke Britain's coasts were put within range of Kriegsmarine bases on the French, Belgium and Dutch coasts, from where they could mount attacks on vital shipping routes in the Channel and the southern part of the North Sea.
A crash building program for torpedo boats, gunboats, and motor launches was rapidly put in place, as was a recruitment program for officers and men to crew these new craft.
At first personnel were drawn from the regular navy and reservists, but then increasingly from the Royal Navy Volunteer Reserve, and ‘hostilities only’ volunteers, such that by the end of the war, Coastal Forces was almost exclusively manned by reservists and volunteers.
All of this activity was initially placed under the dedicated command of a Rear-Admiral Coastal Forces—Piers Keane Kekewich—in late 1940, before being absorbed in the mainstream organisation of the Admiralty later in the war, as a service in its own right.
From a relatively modest beginning, Coastal Forces was to expand throughout the course of the war, to a force of some 1,700 boats, with 25,000 officers and ratings, operating in areas as diverse as the British Isles, the Mediterranean, the coasts of Africa, and the Far East.
This rapid expansion clearly demonstrates the important role the fast motor boat was required to play at all stages of the Second World War. They were to be involved in all the major events of that conflict, from the evacuation at Dunkirk in 1940, through to landings in North Africa, Sicily, and the D-Day landings of 1944, during which they formed a formidable defence guarding the flanks of the invasion forces.
Besides these major events, Coastal Forces boats were involved in separate actions on a daily basis throughout the war, during which time their crews earned numerous awards for gallantry, suffering many casualties in the process.
The nature of this campaign at sea was unlike any previous conflict, and comparisons have been made with the aerial dogfights of the Battle of Britain, in being a form of combat not seen on this scale before, or since. Indeed the fast boats of Coastal Forces were to earn themselves the epithet ‘Spitfires of the Seas’.
Whilst the iconic form of the motor torpedo boat may still command recognition today for its contribution to the wartime defence of Britain, the association of these craft and the men who crewed them with the name Coastal Forces, is a fact less well understood.
Though its exploits were celebrated in news and editorials of the day, and although many informative books have since been written on the subject, including many by veterans who served, today the name of Coastal Forces is more likely to summon up an image of a cliff-top home guard, or be confused with that of Coastal Command—a branch of the Royal Air Force—than be correctly associated with the oftentimes close-combat fighting waged at sea, by men of the navy’s ‘little ships’.
This lack of awareness amongst the general public today is no doubt attributable to the fact that large numbers of boats with their crews were rapidly decommissioned once war in Europe ended in 1945, whilst the branch itself was officially disbanded in 1957 with no modern-day equivalent left to carry on its name, or perform the wartime functions for which it was justly famous.
The different types of motor boat used by Coastal Forces varied in their performance, both in terms of speed, displacement, and armament, in line with the different roles they were to play. Throughout the period of their use during the Second World War they underwent continuous development and refinement, their evolution occurring as a direct response to the threats and opportunities faced in their areas of operation.
The British Power Boat Company designed motor anti-submarine boat, was intended to reprise the role played by the motor launches of the First World War, which had proved decisive in helping to secure Britain's coastal waters from the threat posed by the adoption of unrestricted submarine warfare by Germany.
In the event, the availability of air cover and the development of Asdic helped counter this threat and German submarines mostly steered clear of coastal waters, adopting the tactics of the 'wolf pack' in more open waters of the Atlantic instead.
Since the earlier design of motor torpedo boat proved limited when trying to defend against the better armoured German E-boat, the short-lived MASBs were converted for use as motor gunboats, their armament and engines being upgraded to heavier and more powerful alternatives. This enabled them to provide better protection against marauders, and accompany motor torpedo boats on offensive sweeps, so as to provide them with additional cover fire.
The origins of the motor torpedo boat lay in the earlier design of Coastal Motor Boat (CMB) that the Royal Navy had introduced during the First World War. The successful use of the CMB against much larger warships brought the concept of the highly manoeuvrable, shallow-drafted boat to the attention of the world's navies, particularly those with more limited resources, or facing constraints on building programs, such as those imposed on Germany by the Versailles Treaty of 1919.
When war with Germany broke out in 1939—earlier than certain Royal Navy strategists had anticipated—it was the existence in British yards ironically of boats already on stocks or completed for a number of foreign navies that proved vital. The Royal Navy requisitioned these boats for their own use, in order to strengthen the resources it had available, with which to meet its new found obligations.
The Motor Gunboat was a concept born of clashes early on in the war with German E-boats in the North Sea and English Channel. Conceived as support for the motor torpedo boat to allow greater firepower to be brought to bear in encounters with E-boats, the first dedicated gunboats were converted for use from the earlier MASBs.
Both the early gunboats and torpedo boats were known as ‘short’ boats, on account of their length of between 60–72 feet. Later in the war, the navy introduced a heavier armed boat known as the Fairmile D or ‘Dog Boat’ which measured 115 feet in length. Other manufacturers such as Denny and Camper & Nicholson also produced larger boats, which together with the Fairmile-D were termed ‘long’ boats.
In time the functions of the MTB and MGB were to be combined into a single platform, with new and existing MTBs receiving superior firepower with which to attack or defend themselves, whilst MGBs were equipped with torpedoes to attack larger targets with. On the introduction of these changes, the designation MGB was dropped in favour of the single classification MTB.
The Motor Launch was the largest numerically of the motor boat types used by Coastal Forces. Manufactured by the Fairmile Marine Company founded by Noel Macklin, the Fairmile A, Fairmile B, and Harbour Defence Motor Launch (HDML), were the ‘maids of all work’. They were primarily designed for use in anti-submarine warfare, but were also equipped for use as minelayers or minesweepers, or used as navigation leaders.
Noel Macklin had foreseen the need for levels of coastal protection similar to those required during the First World War, having gained experience of that earlier campaign, during his service as a
To that end, he evolved a radical construction process making use of pre-fabrication methods, that enabled smaller, underused yards to participate in constructing large numbers of these boats in a relatively short space of time.
Photo: Imperial War Museum (A11896) Coastal Forces crew of an Elco MTB in the Mediterranean