Coastal Command was a formation within the Royal Air Force (RAF). Founded in 1936, it was to act as the RAF maritime arm, after the Fleet Air Arm became part of the Royal Navy in 1937. Naval aviation was neglected in the inter-war period, 1919–1939, and as a consequence the service did not receive the resources it needed to develop properly or efficiently. This continued until the outbreak of the Second World War, during which it came to prominence. Owing to the Air Ministry's concentration on Fighter Command and Bomber Command, Coastal Command was often referred to as the "Cinderella Service", a phrase first used by the First Lord of the Admiralty at the time A. V. Alexander.Hendrie 2006, p. 60.

Its primary task was to protect convoys from the German Kriegsmarines U-boat force. It also protected Allied shipping from the aerial threat posed by the Luftwaffe. The main operations of Coastal Command were defensive, defending supplies lines in the various theatres of war, most notably the Battle of the Atlantic. A limited number of detachments served in the Mediterranean, Middle East and African theatres under the control of Coastal Command from 1941, operating from a headquarters in Gibraltar.Franks 2014, p. 2014. Coastal Command squadrons operated from bases in the United Kingdom, Iceland, Gibraltar, the Soviet Union, West Africa and North Africa.Hendrie 2007, p. 90. Coastal Command also served in an offensive capacity. In the Mediterranean and Baltic it carried out attacks on German shipping moving war materials from Italy to North Africa and from Scandinavia to Germany. By 1943 Coastal Command finally received the recognition it needed and its operations proved decisive in the victory over the U-boats.

The service saw action from the first day of hostilities until the last day of the Second World War. It flew over one million flying hoursBowyer 1977, p.43. in 240,000 operations, and destroyed 212 U-boats.Hendrie 2006, p. 179. Coastal Command's casualties amounted to 2,060 aircraft to all causes and some 5,866 personnel killed in action. During 1940–1945 Coastal Command sank 366 German transport vessels and damaged 134. The total tonnage sunk was 512,330 tonsGoulter1995, p. 353. and another 513,454 tons damaged.Hendrie 2006, p. 179. A total of 10,663 persons were rescued by the Command, including 5,721 Allied crews, 277 enemy personnel, and 4,665 non-aircrews.Ashworth 1992, p. 179.

Equipment

Aircraft

On the outbreak of war in 1939 Coastal Command had 18 squadrons. These consisted of ten squadrons of Avro Ansons, including four squadrons manned by the Royal Auxiliary Air Force, two of Vickers Vildebeests, two of Short Sunderlands, three of Saro London and one of Supermarine Stranraers. The Anson had insufficient range for long-range reconnaissance which was left to the flying-boats, four squadrons of which were equipped with the obsolescent Vildebeest and London. Only three squadrons with suitable aircraft, the Lockheed Hudson and Sunderland, were effective. Anson engines were in limited supply in 1939 and the Sunderland and Hudson airframes were also limited, the latter being delivered at a rate of just two per month.Hendrie 2006, p.28. To fill the gap in production capacity, the Air Ministry dispatched several missions to the United States to buy more Hudson airframes.Buckley 1995, p. 104.

The Director of Organisation at the Air Ministry Charles Portal recognised there would be a problem in procurement of aircraft. Coastal Command's operational nature would make twenty-four hour operations a basic requirement. Suitable aircraft for take-off and landing, in particular flying-boats, in all weather was vital for the safety of crews and the effectiveness of the Command. The new twin-engine Saro Lerwick had been touted as the ideal aircraft. It came into service in April 1939 but was a disaster. There was a need for long-range machines to cover the South-Western Approaches and in December 1939 to August 1940, No. 10 Squadron of the Royal Australian Air Force (RAAF) received Sunderlands while No. 235 Squadron, No. 236 Squadron, No. 248 Squadron and No. 254 Squadron were equipped with Bristol Blenheims from RAF Fighter Command in February 1940. In June 1940 No. 53 Squadron and No. 59 Squadron received Blenheims on loan from RAF Bomber Command and two months later No. 98 Squadron was provided with Fairey Battles, also on loan from Bomber Command and based in Iceland. By 15 June a further 15 squadrons were to have been handed over to Coastal Command, this was only achieved by the loan of seven squadrons from other commands, despite an agreement by the Air Ministry and Admiralty. The daily operational strength of Coastal Command amounted to 298 aircraft, most unsuitable for maritime operations. Within a month, that had risen to 39 squadrons and 612 aircraft but they were made of 11 types, causing training and conversion problems.Hendrie 2006, p.28.

By 1 December 1941 the situation was improving. Some 18 Consolidated Catalinas, nine Sunderlands, 20 Armstrong Whitworth Whitley and 170 American Hudsons. The Command's strike aircraft consisted of 60 Bristol Beaufort and 40 Bristol Beaufighters and 60 Blenheim fighter versions for a total of 397 aircraft in 18 squadrons. By June 1942 this figure increased 496 aircraft. Philip Joubert de la Ferté, the commander-in-chief (CinC) of Coastal Command, was not satisfied. He believed the command was short of three land-based and ten flying-boat squadrons. He refuted the Air Ministry's assertions that Coastal Command, in terms of suitable aircraft, was "comparatively well off".Hendrie 2006, p.29.

After Arthur Harris' appointment as CinC Bomber Command, the situation declined. Harris, since his days as a group captain at the Air Ministry's strategic planning division, had attacked the use of resources in maritime aviation, suggesting that bombing enemy shipyards and port facilities would solve the threat to trade defence.Buckley 1995, pp. 70–71. By November 1942, 259 Hudsons were available, but were shared by other services. The Whitley and Hampden were too vulnerable to operate near enemy coastlines without heavy fighter escort. Beaufort squadrons were sent to the Middle East to operate over the Balkans and North Africa. The highly successful de Havilland Mosquito was sought after, but priority was given to the other two air commands. By February 1943, the then CinC Coastal Command John Slessor, had some 850 aircraft, but in respect of quality he was not impressed. Slessor continually wrote to the Air Ministry, complaining that Mosquitoes were being used as reconnaissance machines, while over 200 were being used by the RAF tactical air forces supporting the army, and merchant shipping was suffering high losses in the Atlantic. His successor Sholto Douglas' written records indicate the desire to upgrade, rather than produce new aircraft. By his tenure, January 1944, ten squadrons of Consolidated Liberators, five Vickers Wellingtons squadrons equipped with the Leigh light, and two Handley Page Halifax, Hudson, and Boeing Fortress squadrons were available. Among other technological developments, these long-range aircraft helped defeat the U-boats in May 1943.Hendrie 2006, p.30.

Official requirements

Until the fall of France in 1940, the function of Coastal Command and its aircraft was to cover the English Channel, North Sea and Western Approaches. But the fall of Western Europe and Norway resulted in a vast hostile coastline from the North Cape to the Bay of Biscay. The entry of Italy into the war extended that threat to the Mediterranean. The Irish Sea covering the British western ports required a further three flying-boat squadrons. In total, a further 200 long-range aircraft were needed. The Blackburn Botha was unsuitable and the Anson and Hudson were expected to act as interim solutions. The Anson in particular had limited range and did not possess the capacity to carry heavy weaponry needed to sink a submarine.Hendrie 2006, p.30.

Towards the autumn of 1941, U-boats began operating further into the Atlantic. Coastal Command's requirement programme was 150 Catalinas and 76 Sunderlands for 26 flying-boat units; 32 Liberators and 32 Wellingtons or Whitleys to equip four long-range GR squadrons; 64 Mosquitoes and 180 GR Hudsons for 15 medium to long-range units; 128 Beauforts for eight torpedo-bomber squadrons; and 160 Beaufighters for 10 long-range fighter squadrons. However, four flying-boats and two GR short-range squadrons were to be sent to West Africa, and another three flying-boat squadrons were for Gibraltar.Hendrie 2006, p.31.

By December 1941 operational requirements necessitated aircraft with an extra-long-range of 2,000 miles as U-boats were operating 700 miles from the British Isles. If patrols were deployed 350–600 miles covering port approaches, the enemy would move to the 600–700 mile area and out of range. By then ASV (air-to-surface-vessel) radar homing had been developed, and aircraft were being developed with all-weather and short-take off capabilities. Priority went to Coastal Command Anti-submarine warfare, units by this time.Hendrie 2006, p.31. (Anti-submarine warfare was then denoted "A/S" but since been denoted "ASW")

In January 1942 it was decided that the limit of long-range aircraft endurance should be the crew's limits, (due to extreme aircrew fatigue seriously affecting efficiency) not the fuel supply of the aircraft. De la Ferté decided, on 7 January, sorties should not exceed 14 hours, which reduced flying hours by four per mission. This was despite the entry of the very long-range Liberators in June 1941. The Liberator Mk I had a stated Air Ministry range of 2,720 miles, but crew endurance methods now meant it would be airborne for just 2,240. De la Ferté wrote to the Ministry arguing the Liberator should be used for reconnaissance work, rather than bomb load for the solitary squadron being accepted at that time. The Liberator would assist in closing the 'Mid-Atlantic Gap' which U-boats could operate in without worrying about air interdiction. After replacing Bowhill in 1941, de la Ferté had issued a directive on 12 June 1941 to use Wellingtons and Whitleys as an interim solution to unrestricted submarine warfare now practised by the Germans. Their uneconomical operational cost meant immediate replacement of these medium-range machines was pressing. Some Avro Lancasters and Halifaxes, with some difficulty, were seconded from Bomber Command.Hendrie 2006, pp. 32–33.

The Lancaster was denied as a large-scale or long-term replacement. The Chief of the Air Staff, Portal, argued it was the only aircraft capable of carrying an 8,000 lb bomb to Berlin and could not be spared. As a result, the RAF official history does not include the Lancaster as a Coastal Command aircraft. With a range of 2,350 miles it could have been invaluable. The Boeing Fortress was given to the service only because the Air Ministry considered it unfit as a heavy bomber. It issued a directive on 27 January 1942 stating all Fortresses were to given over to Coastal Command for A/S operations. No. 59 Squadron RAF, No. 206 Squadron RAF and No. 220 Squadron RAF all used the Fortress as successful reconnaissance aircraft. However, the bulk of the force by early 1942 was still medium-range aircraft, which could now reach only 600 miles into the Atlantic. U-boats were now operating at 700 miles plus.Hendrie 2006, p. 34.