A recipe for obsolescence? British naval torpedo bomber development in the 1930s

The Fleet Air Arm led developments in torpedo attack using landplanes flying from aircraft carriers between the two world wars. How is it then, that until the last two years of the Second World War, the service was equipped with aircraft that were utterly outdated? The Fairey Swordfish and to a lesser extent the Albacore were undoubtedly popular with their crews and despite their vulnerability to enemy fighters enjoyed some spectacular successes.

Nevertheless, traditional biplanes were clearly becoming anachronistic by the mid-1930s when the Swordfish entered service – so how was it that the Fleet Air Arm found itself bringing a wire-braced, fixed undercarriage biplane into service as late as 1940? To answer this question it is necessary to look into Fleet Air Arm tactical thinking and procurement in the 1930s.

Blackburn Baffin
The Blackburn Baffin was the Fleet Air Arm’s main torpedo bomber from 1934-1936

By the time an armistice was signed in November 1918 the naval wing of the RAF had planned what would have been the first carrier torpedo strike against an enemy fleet. Sopwith Cuckoos flying from HMS Furious and HMS Argus were to have carried out an attack on the German High Seas Fleet but the end of the war saw an end to the proposed attack.

After the First World War ended, development of carrier launched torpedo attack continued. The Fleet Air Arm as a whole did not prosper under RAF control in the austere 1920s and 1930s, but the importance of torpedo attack was such that Britain’s capability remained at the state of the art for the first decade after the war and beyond. After the end of the First World War, the carrier-launched aircraft quickly replaced the ‘big gun’ as the primary method of countering an enemy battle fleet.

The first purpose-built torpedo aircraft for flight deck operations, the Cuckoo, was replaced by the more capable Blackburn Dart in 1923. When engines became powerful enough to carry both a torpedo and a second crew member, the Dart was replaced by the more practical Blackburn Ripon in 1930.

In view of its later virtual monopoly in British naval torpedo aircraft, it is perhaps surprising that the Fairey Aviation Company Ltd had not made any serious attempt to offer a torpedo bomber to the Fleet Air Arm until the mid-1930s. The company known as ‘Faireys’ had been formed in 1915 and had strong links to British naval aviation. The first aircraft designed for use on an aircraft carrying ship was the Fairey Campania floatplane of 1917, and Fairey designs had equipped the Royal Navy’s aircraft carriers solidly from 1926.

While Blackburn specialised in torpedo aircraft, Fairey had specialised in spotter-reconnaissance aircraft with the highly successful III series of biplanes, and to a lesser extent fighters with the popular Flycatcher.

Fairey’s interest in torpedo bombers came about as a result of moves in naval aviation circles to reduce the number of separate types used aboard aircraft carriers by increasing the number of roles that each aircraft could carry out.

In 1930, naval aviators had begun to formulate their thinking around this concept, spurred by a paper written by officers of the carrier HMS Courageous. Instead of the traditional three types it was proposed that RN carriers operate two types per ship. The RN’s current standard types were a three-seat aircraft for reconnaissance and spotting the fall of shot for naval gunnery (known as a ‘spotter-reconnaissance’ type), a two-seat torpedo-strike aircraft and a conventional single-seat fighter.

The proposed new types would combine the role of torpedo-bomber and spotter-reconnaissance into a single aircraft, along with a two-seat fighter that could also conduct reconnaissance and carry bombs.

Swordfish
The Swordfish and its anticipated main weapon, the MkXII torpedo. It represented a relatively small improvement over the Baffin

Coincidentally, in 1930 Fairey had prepared a design for a biplane for the Greek Navy, which would be able to carry a torpedo as well as undertake reconnaissance and gunnery-spotting duties. The design was based on an aircraft that was being prepared for the Air Ministry to Specification S.9/30 for a relatively straightforward replacement for the Fairey Seal, the last of the III series line.

The Air Ministry, having considered all these developments, scrapped Specification S.9/30 and a requirement for a new torpedo bomber, M.1/30, and created a new requirement combining the two roles. This was classified S.15/33 and led to the first ‘TSR’. Indeed, the Fairey prototype was labelled ‘TSR I’ – this led to the TSR II, the Swordfish of 1934.

While the Swordfish was under development, the FAA had made another decision which was more to do with economy and a gradual, incremental improvement that was felt to be sufficient at the time. The improvement in relatively lightweight, simple air-cooled engines prompted the FAA to re-engine its Ripon fleet with Bristol Pegasus radials replacing the Napier Lion liquid-cooled engines. The aircraft was renamed Baffin, as if to suggest that the reworked aircraft was a new type. In reality, most Baffins were the FAA’s old Ripons modified to accept the new engine. The change led to a useful increase in range and a slight improvement in performance, but development was already falling behind the state of the art.

The Baffin’s replacements, the Shark and Swordfish offered again an only incremental increase in performance. However, the responsive yet forgiving nature of the Swordfish, along with its robust and simple construction, made it an instant hit with the FAA. Blackburn’s Shark, developed to roughly the same requirement as the Swordfish, represented a moderate stride towards modernity; it was still a biplane with fixed undercarriage, but replaced the Baffin’s canvas-covered fuselage with an all-metal monocoque, while the wings did away with bracing wires through ‘warren girder’ struts. Nevertheless, the qualities of the slower, more old-fashioned Swordfish were sufficient to overturn Blackburn’s two decades of superiority in torpedo aircraft. The Fairey aircraft became the Royal Navy’s sole torpedo-spotter-reconnaissance in the late 1930s and early 1940s, supplanting the Shark which was relegated to second-line duties.

By this time, the Fleet Air Arm’s TSR aircraft were required to carry equipment which might be needed, if not all at once, for torpedo attack, bombing, long-range navigation, reconnaissance, gunnery spotting and numerous other duties such as smokescreen-laying. The Swordfish managed this all with aplomb.

It was nevertheless apparent even to the Admiralty and the Air Ministry that the Swordfish was by no means a modern aircraft by the standards of 1934. It had taken four years to bring into service an aircraft that could do all that was required of it, in addition to being an effective deck-landing aeroplane that was tough enough to stand up to the rigours of shipboard service.

With evidence of the muddled thinking that would blight future naval aircraft requirements, the Air Ministry issued two specifications for a replacement, a ‘TSR’ (M.7/36) and a dive bomber (O.8/36). However, these were swiftly cancelled for reasons that are unclear. The requirements had called for a slow stalling speed of 58 knots (66 mph) and a high cruising speed with torpedo of 183 knots (210 mph) and as with some other contemporary requirements, the large difference may have proved too challenging for design houses at the time.

Fairey had begun work on a design to M.7/36 but its offering came nowhere near the specification’s performance requirements. Nevertheless, the Admiralty was apparently happy with a marginal improvement on the Swordfish. It went ahead and created Specification 41/36 around the Fairey design, which was ordered into production as the Albacore.

Fairey S14/36
The Fairey S.14/36 was ordered into production as the Albacore to replace the Swordfish, despite being obsolescent before leaving the drawing board

It was becoming clear that in an era of rapid advances in aircraft design, the RN was arguably over-emphasising docile handling and deck-landing qualities at the expense of performance. Maximum speed of RAF fighters between 1930 and the introduction of the Hawker Hurricane, which like the Albacore was ordered into production in 1936, rose from the 178 mph of the Bristol Bulldog to the early Hurricane’s 320 mph. Indeed, at the time 41/36 was issued, both the Spitfire and Hurricane had flown at around double the Albacore’s top speed. By contrast, the maximum speed of the RN’s torpedo bombers/TSRs in the same period rose by a mere 25 mph, from the 136 mph of the Blackburn Baffin to the 161 mph of the Albacore.

Even this did not raise many eyebrows in the Admiralty and Air Ministry in 1936. It was generally considered that high-performance aircraft would not make practical carrier aircraft. Secondly, there was no imperative to improve the performance of carrier-based aircraft because it was thought that they would not have to face high-performance land-based aircraft in combat. It was not until the Norwegian campaign of 1940 that this thinking would be shattered completely. The Albacore entered operational service the month prior to Hitler’s invasion of neutral Norway, and did not operate from a carrier until November, the month Swordfish from HMS Illustrious struck at Italian capital ships at Taranto.

The Admiralty had compounded the order of the arguably obsolescent Swordfish in 1934 with the order of the arguably obsolete Albacore two years later. But thinking was changing. By the time the Albacore was ordered, the US Navy was preparing to equip its torpedo squadrons with the Douglas TBD Devastator, an all-metal monoplane torpedo and level bomber which was capable of 206 mph. Meanwhile in Japan, the 235 mph Nakajima B5N (the main torpedo bomber at Pearl Harbour) had already made its first flight.

British aircraft manufacturers were not blind to the rapidly advancing state of the art. Blackburn and Fairey submitted private venture proposals for a modern TSR in the summer of 1937. Though the Blackburn was felt to have too low a performance and the low wing, twin-engined layout of the Fairey offering was felt to be unsuitable, the proposals were a spur to a new specification.

Unfortunately, though the decision to create a more high-performance torpedo aircraft was taken in 1937, indecision and confused thinking conspired to delay the resulting aircraft entering service almost until 1944.

The specification that was drawn up in 1937 continued the orthodoxy that had held sway in British naval aviation since the early 1930s – namely, the emphasis was on multi-role capability rather than excellence in any one area. The Fleet Air Arm was aware that its chief weapon was torpedo strike against enemy shipping, but was also enthusiastic about the potential of dive bombing. The FAA was still required to spot the fall of shot for the big guns of the RN’s capital ships and cruisers, and reconnaissance capability was essential for both finding the location of an enemy to strike at, and discovering potential threats to the surface fleets. In the late 1930s the FAA did not benefit from anywhere near the same level of resources for rearmament that the RAF enjoyed, so versatile aircraft made the most of small numbers of airframes and limited personnel to operate them.

The new aircraft would be expected to carry the MkXIIA aerial torpedo, and 250 lb and 500 lb bombs when acting as a dive bomber. The specification asked for similar performance figures to the cancelled 1936 requirement. It stipulated that the TSR/TBR should be able to cruise at 185 knots (212 mph), land at 58 knots (66 mph) and have an endurance of six hours at reconnaissance load and a range of 600 nautical miles at strike load. It is probably no coincidence that the performance requirements were almost identical to those of the cancelled M.7/36. The new specification can in part be regarded as a merging of the previous specifications for a TSR and a dive bomber, as well as being another attempt to persuade the industry to come up with an aircraft of the required performance and capability.

A British built, air-cooled engine was preferred, and it had to have passed its 100 hour type test. The aircraft was not to exceed an all-up weight of 10,500 lb as a shipboard aircraft. Consideration was to be given to configuring the aircraft as a float plane. Most significantly, only monoplanes would be accepted.

Six manufacturers responded to the invitation to tender. Even so, many of the entries did not have all the modern features of types already entering service in the US and Japan. Of the six entries, all but Fairey’s had fixed undercarriage. Westland’s submission lacked cantilever wings, with the shoulder-mounted mainplanes braced by large struts. Part of this can be attributed to the requirements for high visibility for the Observer. All the entries had been required to adopt a high or shoulder-mounted wing to ensure aerodynamic stability while keeping the field of view clear. The high wing required either a fixed undercarriage or a complex, heavy retractable solution. (Long oleo legs are by their nature heavy and more prone to failure).

There were, nevertheless, one or two innovative features among the six entries – Supermarine’s Type 322 had an electrically-powered variable-incidence wing, while the Westland P.10/11 boasted an internal weapons bay. Hawker’s submission had power-folding wings, while Fairey’s Type 100 had an auxiliary aerofoil aft of the wing that acted as a flap, dive-brake and increased wing area and efficiency in cruising flight. Fairey’s design was chosen, and eventually emerged as the Barracuda.

The complex and conflicting requirements of the specification undoubtedly made it more difficult for the manufacturers to come up with a practical aircraft of the requisite performance. The subsequent cancellation of the chosen engine, the 1,200 hp Rolls Royce Boreas added to the delays. Nevertheless, the complex specification led to a complex aircraft which took time to prepare for service. The first two prototypes were ordered in January 1939 – the first prototype first flew in December 1940, and the Barracuda finally became operational in late 1943.

By comparison, the American Grumman TBF Avenger was conceived two years after S.24/37, flew in prototype form seven months after the Barracuda did, and beat it into service by over a year.

A combination of complacency and an over-emphasis on practicality and versatility had left the Fleet Air Arm’s torpedo attack capability struggling to catch up with its major rivals in the mid-1930s. When the need for a high-performance replacement for the Swordfish was belatedly recognised, confused requirements, over-ambition in performance and reluctance to sacrifice maid-of-all-work types hampered the development of a new type.

In the meantime, the Swordfish and Albacore had soldiered on. In reality, the role for which all three FAA aircraft had been conceived – striking against an enemy battle fleet – did not fully arise again after the Swordfish’s miraculous night attack on the Italian fleet at Taranto. The first major task the new Barracudas were prepared for was to protect the seaborne invasion of Italy in September 1943 against the threat of the remaining Italian fleet. Ironically, when the fleet surrendered, Barracudas were scrambled to protect the Italian warships en route to Malta from a possible attack by German vessels.

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2 responses to “A recipe for obsolescence? British naval torpedo bomber development in the 1930s

  1. interesting and well researched. One point which has to be made is that the Swordfish was remarkably more successful than the more advanced B5N or the TBD in it’s tactical employment. It’s successes at Taranto and against Bismark changed the balance of power at a strategic level.

    The TBD is known only for being massacred at Midway and the B5N although probably the best technical carrier attack aircraft at the beginning of WWII, never was able to create a positive strategic impact.

    I have even heard that the Swordfish was so slow that it was impossible to track using modern shipboard anti-aircraft weapons.

    The String Bag, despite it’s age and limits, was a game changer.

    • Thanks for your comment and your kind words. You’re absolutely right that the Swordfish had a strategic effect on the war in several operations, and is among the most successful torpedo bombers of the early war period. I hadn’t heard about it being too slow to track using shipboard AA guns, though that sounds plausible – it was certainly able to fly below the elevation of larger AA guns because of the confidence it inspired. That is a message that comes through when you speak to the RNHF, for example, which is that the Swordfish was a confidence-inspiring aircraft that its crews had total faith in. In the air, it would not bite, and all components were stressed to 9G so it could be thrown around with abandon. Where there were modern fighters in the vicinity though, it was too vulnerable, so as the war progressed it would have been too dangerous to keep in the frontline TBR role. Thanks again

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