First World War RAF Coastal Patrols


ROYAL NAVAL AIR SERVICE RNAS 1914-1918 (Q 67581) Curtiss H.12


Fairey designed the Campania floatplane in response to the Royal Navy’s specification for a purpose-built, two-seat patrol and reconnaissance aircraft. The initial prototype first flew on 16 February 1917. This was the first of two prototypes, designated F.16 which was powered by a 250 hp (190 kW) Rolls-Royce Eagle IV. The second prototype was powered by a 275 hp (205 kW) Eagle V engine, it was designated F.17. Both prototypes would later see active service operating from Scapa Flow.

Great Britain declared war on Germany on 4 August 1914. On 5 September, Korvettenkapitän Hersing in U-21 sank the light cruiser HMS Pathfinder off St Abbs Head. On 22 September, Leutnant Weddigen in U-29, sank three ships – the British cruisers Aboukir, Cressy and Hogue. On 1 January, 1915 U-24 sank HMS Formidable. British submarines had sunk the German cruiser Hela, the destroyer S-116 and the Turkish battleship Messoudieh. A response was soon to come. The German Zeppelin L-5 made the first-ever attack on a submarine, HMS/ME11, but missed. On 15 May, 1915 Kapitänleutnant Heinrich Mathy in Zeppelin L-9 attacked three British submarines. None were sunk, but one of them, the D-4, was severely shaken.

The Royal Navy by now saw the value of aircraft patrols to keep down the U-boats, but in the first part of 1915 the service had only three airships and a number of small seaplanes. However, by the end of the year, at the instigation of Lord Fisher, the First Sea Lord, the RN had 29 purpose-built airships in service. These were Submarine Scouts, small non rigid airships, designated SS and generally known as blimps. Some 200 of these were built. They were equipped with wireless and one or two machine guns and could carry a small bomb load. Aeroplanes were also making attacks on submarines. Whether or not kills were achieved was difficult to ascertain, but certainly life was being made difficult for them. Sightings of course were made visually, but frequently submarines saw the aircraft before the aircraft saw the submarine and were below the surface by the time the aircraft was on top. Even if no attack was made, part of the object had been achieved -to deny the submarine the use of the surface. The chances of an aircraft making a kill were not high, as the bombs in use at that time were not powerful enough to damage the pressure hull. However they could cause damage to the hydroplanes, causing the submarine to go out of control. Damage to the pressure gauges or the high-pressure air system could lead to the loss of a submarine. High-pressure air was used to blow water from the ballast tanks, enabling the boat to surface. There was always the danger of sea water getting into the batteries, reacting with the sulphuric acid and thus releasing chlorine gas into the boat.

In 1914 the Curtiss Company in the United States of America built a twin-engined flying boat called the America for transatlantic flying. Such an aircraft, with its long range, albeit with only 90 hp engines, would be ideal for maritime flying. The RN bought it and others and they came into service in 1915. It was called the Curtiss H-4. The aeroplane had an all-up weight (AUW) of 5000 pounds, carrying a small bomb load and two machine guns. It was not very successful, but the idea was on the right track.

Curtiss then built the H-8, the Large America, with an AUW of 10,000 pounds and two 160 hp engines, giving a speed of 85 miles per hour. However it proved to be as underpowered as the H-4. The RN bought 50 of these to be stationed at Felixstowe. The first machines arrived in July 1916. The station commander, Wing Commander (RNAS rank) John Porte, had one of them re-engined with two Rolls Royce Eagle engines of 250 hp each. This gave an increase in power of 50 per cent and the aircraft came into service as the H-12 Large America. However, the Rolls Royce engines were in short supply and until these problems were sorted out, the short range Short 184 seaplane carried out anti-submarine work.

At the beginning of the war, a surprise attack against a warship by a submarine was a legal act of war; against a merchant ship, it was not. The submarine had first to surface, send a boarding party and check that the cargo was prohibited. Only then was the submarine commander allowed to sink the ship, although he was still responsible for the safety of the ship’s crew. The Germans did not like this as the British had mounted a blockade against Germany, and they saw these rules as unfair. In February 1915 the Kaiser ordered his commanders to ignore the rules and to sink any ship found in the war zone around the UK.

The submarine in 1914 was basically a submersible torpedo boat. It had diesel engines for use on the surface and electric motors powered by batteries for use underwater. The batteries were charged by the diesels when running on the surface. The maximum submerged speed was only 9 knots, whereas on the surface it was nearer to 15 knots. The electric motors gave a maximum range of about 60 miles, so most U-Boat commanders preferred to remain on the surface, leaving the electric motors for emergency use. When an aircraft sighted a submarine, the boat had to submerge or be attacked. In addition the submarine commander did not know when or if the aircraft had gone away, so he had difficulties giving the order to surface. Thus the aircraft could prevent the submarine from reaching its target.

As the war progressed the U-Boat became a greater menace and the United Kingdom was losing many ships. In 1917 the device used in the Napoleonic wars and previously was reintroduced – the convoy system. This had been difficult to implement as the ship owners were against the idea. The speed of the convoy was the speed of the slowest ship, increasing voyage times and reducing income. They also believed that such a large target would attract U-Boats and that sinkings would increase. The ship masters were against it, as they would be subordinate to Royal Navy Officers and their capacity for action at sea and ashore would diminish sharply. RN officers were against it as well, as it was not considered to be “offensive” but “defensive”.

The Admiralty ignored the fact that troopships had been convoyed since August 1914 and that the Hook of Holland trade route had been convoyed since 1916.There had been six losses, all before mid-1917. Other arguments against convoys were that large ones would be unable to zigzag, congestion would occur at the ports, masters would not be able to keep station, a separate escort would be needed for each merchant vessel and a convoy presented a larger target.

The advantages were that the ships were more difficult to find, and when they were found the U-boats were up against more escorts. While there were more ships, the U-boat could only attack one at a time. Escorting aircraft and ships would be employed more efficiently. A trial convoy sailed in May 1917 from Gibraltar and was a success. A further trial convoy sailed from the USA. Ten ships that stayed in the convoy arrived safely, but two which could not keep up with it were sunk. The system was instituted and an immediate reduction in losses was achieved. For example, Alfred Price in his Aircraft Versus Submarine states that in April 1917 834,000 tons were lost. With the introduction of the convoy in May, losses averaged 590,000 tons in May and June and 430,000 in the following three months. The submarine now, instead of waiting for individual ships, had to positively look for them. When they had found them they also met escorts, both warship and aeroplane. The aircraft, by forcing submarines to submerge, assisted in the “safe and timely arrival of the convoy”.

The escorts being equipped with depth charges and hydrophonic listening devices, now began to achieve sinkings. Instead of looking for U-Boats, the U-Boats were coming to them. By the end of the war, aircraft were being equipped with hydrophone systems, although the flying boat had to alight on the sea to use it. Airships were also equipped with the systems, but they had only to hover to use them. No successes were gained, but it was useful experience for the next war.

In 1918, the U-boats, gaining no successes in the Western Approaches, now tried coastal waters around the UK. To counteract this, it was decided to increase the number of aircraft on the strengths of the various flying boat and seaplane bases with the addition of land-based aircraft. It was well known that U-Boats submerged when sighting any aircraft, whether armed or not. There were about 300 surplus de Havilland DH 6’s available, and these were chosen for the job. Around 220 of them were fitted with a pilot, a 100lb bomb and no observer and the remainder flew with a pilot, an observer and no bomb. Just under 4900 seaplane and landplane sorties were flown in 1918 and in that time only two ships were attacked when being escorted. However, when the weather prevented flying, then the U-Boats moved in.

On 19 April 1918 orders were given for the formation of seven DH6 flights, to be known as Special Duty Flights. The patrols they flew were known as “scarecrow” patrols. The DH6 was a trainer but had been superseded by other types, so there was a large surplus of them available. The logic of the patrol was that if a submariner sighted any aircraft he would submerge his boat, as this was certain protection. A U-Boat had at most two machine guns for anti-aircraft protection. The deck gun could not be elevated high enough to shoot at aircraft.

The flights were to be given squadron numbers, starting with No 250 Squadron. However, in practice, the DH6’s were mixed with other aircraft and other squadrons.

No 250 Squadron was formed at Padstow, Cornwall on 1 May 1918 out of Nos 494, 500, 501, 502 and 503 Flights, using DH6’s and DH9’s. There was a detachment to Westward Ho! in May where Nos 502 and 503 Flights were formed into No 260 Squadron in August. It was disbanded in May 1919.

No 251 Squadron was formed at Hornsea on 1 May 1918 out of Nos 504, 505, and 506 Flights using DH6’s and DH9’s. No 252 Squadron was formed at Tynemouth on 1 May 1918 out of Nos 451, 452, 495, 507, 508, 509 and 510 Flights using DH6’s, Sopwith Baby’s and Blackburn Kangaroo’s. It was disbanded in June 1919. No 252 Squadron was formed in May 1918 at Tynemouth from Nos 451, 452, 495, 507, 508, 509 and 510 Flights. It was equipped with Sopwith Babys and Kangaroos until August 1918 and DH6s until January1919. There were detachments at Seaton Carew, Redcar and Cramlington. The Squadron moved to Killingholme in January 1919 as a cadre and disbanded in June. No 253 Squadron was formed at Bembridge, Isle of Wight in June 1918 out of Nos 412, 413, 511, 512 and 513 Flights with Short 184s, Fairey Campanias and in August DH6s. In August No 513 Flight detached to Chickerell and formed the basis of No 241 Squadron. The squadron disbanded in January 1919.

No 254 Squadron was formed at Prawle Point, Plymouth in May 1918 out of Nos 492, 515, 516, 517, and 518 Flights with DH6s and DH9s. No 492 Flight was one of the elements of No 260 Squadron. Nos 515 and

516 Flights were the basis of No 236 Squadron when they detached to Mullion. The squadron disbanded in February 1919.

No 255 Squadron was formed at Pembroke in July

1918 out of Nos 519, 520, 521, and 522 Flights with DH6s. It disbanded in January 1919.

No 256 Squadron was formed at Seahouses in June 1918 out of Nos 495, 525, 526, 527 and 528 flights with DH6s. In November it received Kangaroos when No 495 Flight was moved from No 246 Squadron. It disbanded in June 1919.

No 257 Squadron was formed at Dundee in August 1918 out of Nos 318 and 319 Flights with Curtiss H-16s, Felixstowe F2As and F3s. The Squadron disbanded in June 1919.

No 258 Squadron was formed at Luce Bay in July 1918 from Nos 523, 524 and 529 Flights with DH6s. It became a cadre in December 1918 and disbanded in March 1919.

No 260 Squadron was formed at Westward Ho! in August 1918 from No 492 Flight from No 254 Squadron, and Nos 502 and 503 Flights from No 250 Squadron, with DH6s and DH9s. It disbanded in February 1919. No 272 Squadron was formed at Machrihanish, near Campbeltown, in July 1918 from Nos 531, 532 and 533 Flights. It was equipped with DH6s initially and in November, Fairey IIIAs. The Squadron disbanded in March 1919.

No 259 and No 261 Squadrons were authorized to form at Felixstowe but in the event this did not happen. Nos 342, 343 and 344 Flights were to be No 259 Squadron and Nos 339, 340 and 341 Flights were to be No 261 Squadron. Both units were to be equipped with Felixstowe F2As.

There were other squadrons outside the above numbering.

No 236 Squadron was formed in August 1918 at Mullion in Cornwall from Nos 493, 515 and 516 Flights with DH6s and DH9s. Nos 515 and 516 Flights were part of No 254 Squadron and had been detached to Mullion. No 241 Squadron was formed in August 1918 at Portland with DH6s, Short 184s, Fairey Campanias and Wight Converteds from Nos 416, 417 and 513 Flights. These squadrons were allocated to Groups as follows:


No 236 Squadron

No 250 Squadron

No 254 Squadron

No 260 Squadron



No 241 Squadron

No 242 Squadron

No 253 Squadron



No 244 Squadron

No 255 Squadron



No 251 Squadron

No 252 Squadron

No 256 Squadron



No 258 Squadron

No 272 Squadron


The following squadrons were formed in the UK in August 1918:

  1. No 228 Squadron from Nos 324, 325 and 326 Flights at Great Yarmouth, with Felixstowe F2As and Curtiss H16s.
  2. No 229 Squadron at Great Yarmouth from Nos 428, 429, 454 and 455 Flights, with Sopwith Babies, Hamble Babies, Short 184s and Short 320s.
  3. No 230 Squadron at Felixstowe from Nos 327, 328 and 487 Flights, with Curtiss H16s and Felixstowe F2As. In September Sopwith Camels, Felixstowe F3s and Short 184s were added. Fairey IIIB/Cs were also added.
  4. No 231 Squadron at Felixstowe from Nos 329 and 330 Flights, with Felixstowe F2As.
  5. No 232 Squadron at Felixstowe from Nos 333, 334 and 335 Flights, with Felixstowe F2As.
  6. No 233 Squadron at Dover from Nos 407, 471 and 491 Flights.
  7. No 234 Squadron at Trescoe, Scillies, from Nos 351, 352 and 353 Flights.
  8. No 235 Squadron at Newlyn, Cornwall from Nos 424 and 425 Flights.
  9. No 236 Squadron at Mullion, Cornwall from Nos 493, 515 and 516 Flights.
  10. No 237 Squadron at Cattewater, Plymouth from Nos 420 and 421 Flights.
  11. No 238 Squadron at Cattewater, Plymouth from Nos 347, 348 and 349 Flights.
  12. No 239 Squadron at Torquay from No 418 Flight. 13. No 240 Squadron at Calshot from Nos 345, 346 and 410 Flights.
  13. No 241 Squadron at Portland from Nos 416, 417 Flights and from No 253 Squadron, No 513 Flight while at Chickerell.
  14. No 242 Squadron at Newhaven from 408, 409 and 514 Flights with Short 184s, DH6s, Fairey Campanias and Wight Converteds.
  15. No 243 Squadron at Cherbourg from Nos 414 and 415 Flights, with Short 184s and Wight Converteds. 17. No 244 Squadron at Bangor from Nos 521, 522 and 530 Flights, with DH6s.
  16. No 245 Squadron at Fishguard from Nos 425 and 427 Flights, with Short 184s.
  17. No 246 Squadron at Seaton Carew from Nos 402, 403, 451, 452 and 495 Flights, with Fe2bs, Blackburn Kangaroos, Short 184s, Short 320s and Sopwith Babies. The Kangaroos came with No 495 Flight, which came from No 252 Squadron.
  18. No 247 Squadron at Felixstowe from Nos 336 and 337 Flights, with Felixstowe F2As.
  19. No 248 Squadron at Hornsea from Nos 404, 405 and 453 Flights, with Short 184s and Sopwith Babies.
  20. No 249 Squadron at Dundee from Nos 400, 401, 419 and 450 Flights, with Sopwith Babies, Hamble Babies and Short 184s.
  21. No 273 Squadron at Burgh Castle from Nos 470, 485, 486 and 534 Flights with DH4s, DH9s and Camels. There were detachments at Covehithe, Westgate and Bacton. The Squadron was reduced to a cadre in March 1919, moved to Great Yarmouth and disbanded in June 1919.

It had been intended to form No 274 Squadron at Seaton Carew in November 1918 with Vickers Vimys in the antisubmarine role, but the end of the war made that unnecessary.

Meanwhile in the Mediterranean/Aegean Seas further squadrons were formed on 1 April 1918:

No 220 Squadron at Imbros from C Squadron on No 2 Wing RNAS. These elements became Nos 475, 476 and 477 Flights. It was equipped with DH4s and then in June, DH9s. In July, Sopwith Camels came on to the inventory. Two months later, in September, the Squadron adopted the No 220 Squadron number plate.

No 221 Squadron was formed at Stavros from D Squadron of No 2 Wing RNAS. These elements became Nos 552, 553 and 554 Flights. It was equipped with DH4s and Camels and in June, DH9s were added. Again, in September, the Squadron adopted the No 221 Squadron number plate.

No 224 Squadron at Alimini from No 6 Wing RNAS. These elements became Nos 496, 497 and 498 Flights. It was equipped with DH4s and in May DH9s were added.

There was some confusion over how these units were formed. While the RAF allocated the number plates on the date of formation of the Royal Air Force (1 April 1918), these units combined with others to form other squadrons (numbered alphabetically) and the original RAF intention was not carried out. The genealogy above is probably correct. See Annex L of Wing Commander C. G. Jefford’s book RAF Squadrons.

Further squadrons were formed in September:

  1. No 263 Squadron at Otranto from Nos 359, 435, 436 and 441 Flights, with    Sopwith Babies, Hamble Babies, Short 184s, Short 320s and Felixstowe F3s. It disbanded in May 1919.
  2. No 264 Squadron at Suda Bay from Nos 439 and 440 Flights, with Short 184s. It disbanded in March 1919.
  3. No 266 Squadron at Mudros in the Aegean Sea from Nos 437 and 438 Flights, with Short 184s and Short 320s. It had a detachment at Skyros and moved to Talikna in January 1919. The next month it went to the Caucasus on board HMS Engadine, thence to Petrovsk and flew operations from HMS Aladar Youssonoff and HMS Orlionoch. The Squadron withdrew in August and went to Novorossisk. It disbanded in September 1919.
  4. No 267 Squadron at Kalafrana from Nos 360, 361, 362 and 363 Flights, with Short 184s, Felixstowe F2s and F3s. There were detachments at Alexandria and Port Said. Fairey IIIDs were added to the inventory in December 1920 and had detachments on HMS Ark Royal and at Kilya Bay. The Short 184s and Felixstowe F.3s were disposed of in 1921 and the Squadron disbanded in 1923, being redesignated No 481 Flight.
  5. No 268 Squadron at Kalafrana from Nos 433 and 434 Flights, with Short 184s and Short 320s. It disbanded in October 1919.
  6. No 271 Squadron at Taranto, Italy from Nos 357, 358 and 367 Flights, with Short 184s and Felixstowe F3s. It disbanded in December 1918.

No 265 Squadron was supposed to form at Gibraltar with Short 184s and Felixstowe F3s, but the project was cancelled.

The following squadrons were formed in October


  1. No 269 Squadron at Port Said, Egypt from Nos 431 and 432 Flights, with BE2es and Short 184s. In December 1918 DH9s were added to the inventory and the following month it moved to Alexandria with a detachment at Port Said. The Squadron disbanded in November 1919, being absorbed by No 267 Squadron.
  2. No 270 Squadron at Alexandria, Egypt from Nos 354, 355 and 356 Flights, with Sopwith Babies, Short 184s and Felixstowe F3s. In December 1919 it disbanded, being absorbed by No 269 Squadron.

It will be apparent from the above that squadron and flight numbering was somewhat confusing, in that flight numbers were retained within squadrons and some flights were transferred between squadrons.

By 1917, the Large Americas were showing signs of deterioration to the hulls. Wing Commander Porte designed a better hull, improved the tail surfaces and fitted two Rolls Royce engines. This aircraft became the Felixstowe F-2A. It was armed with two 230 pound bombs and carried fuel for eight hours.

The first land plane to be used in maritime work was the Blackburn Kangaroo. At a maximum all-up weight of 8000 pounds this aircraft weighed less than the Felixstowe but carried 920 pounds of bombs, was faster and had a better endurance. It only served with No 246 Squadron and in its six-month war service its crews sighted twelve U-boats, attacked eleven and shared in the destruction of UC-70.

The first sign of a detection device to be used with ever greater effect, in the Second World War and after, was sound. Early in the war British scientists carried out experiments with hydrophones to detect the sound of a submarine. These were successful and the device was carried on ships and on shore stations. The idea of fitting one of these to an aircraft came shortly after. However, the aircraft had to land on the water to operate it and the engines had to be switched off. This was not very appealing to crews in the middle of the ocean, or even the English Channel, as there was no guarantee that they could be restarted. The equipment was not very useful therefore, but fitted to the blimps it was more effective, as they did not have to alight on the sea. They did however, have to switch off the engines. These hydrophones were of the non-directional type but in 1918 trials using directional hydrophones were carried out and proved to be more effective.

The Great War, as it was originally known, was the first time that submarines had been used in strength against shipping and the first time aeroplanes had been used in the antisubmarine role. A number of lessons were learned. Air cover for ships, even if the aircraft were unarmed, was vital. To be really effective, continuous cover was required. Aircraft with long endurance were better than those with short endurance. It had been shown that aircraft could sink submarines but that it was necessary for the weapon to explode very close to the target, if not on it. Speed was vital. Once the submarine had sighted the aircraft, it had to attack the boat before it was completely submerged. Aircraft crews could not see submerged submarines unless the sea was clear and the aircraft was on top. Such conditions were only found in the lower latitudes, and certainly not in the North Atlantic. They could see the “feather” of a periscope only in relatively calm conditions. A surfaced submarine could be seen, but the detection range diminished with sea state. The convoy system was probably the best countermeasure against submarines and with air cover it was even better.

The RNAS was in action in the Dardanelles in 1915 in the bombing and anti-ship roles. Commander Samson arrived with an advance party, soon to be strengthened with eighteen aircraft and crews from the RN and the army. Operations were carried in support of the British submarine E15 with bombing attacks on shore batteries, spotting for the artillery and reconnaissance. This last involved several aircraft and was on a daily basis.

The first attack on a battleship was carried out. This was the obsolete Heireddin Barbarossa, which was sunk by Lt.Cdr. Nasmith in aircraft E11. In August 1915, Flight Commander Charles Edmonds, operating from the carrier Ben-My-Cree, attacked and sank a 5000-ton Turkish supply ship. This, the first successful torpedo attack by an aircraft, was followed up five days later when Edmonds sank three tugs. Flight Lieutenant D’Acre, having engine problems, landed on the sea and taxied towards a large tug. He launched a torpedo which sank the ship. He was then able to take off and returned to the Ben-My-Cree.

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