Supermarine special: The First of the Future

First in a series of Naval Air History specials on Supermarine’s contribution to naval aviation – the first swept wing jet to successfully land on an aircraft carrier.

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One of the catalogue of almost unremarked but nonetheless significant aviation ‘firsts’ in the postwar period was claimed by Supermarine, despite its star then being on the wane as an aircraft manufacturer. This was the first landing of a swept-wing jet on an aircraft carrier, which took place in late 1950.

Supermarine 510
The first swept-wing jet to land on an aircraft carrier was the Supermarine Type 510 VV106

The Supermarine Aviation Works made a significant contribution to naval and maritime aviation in its own right and later when part of Vickers, although this is generally overshadowed by that company’s superlative land-based fighter, the Spitfire. Nevertheless, Supermarine continued working on naval aircraft until the name finally disappeared in the late 1950s and its last design to enter production was a naval fighter, the Scimitar.

This achievement was remarkable for a number of reasons. At the time, the UK was drastically scaling back spending on military development, and in truth the country had already ceded a lead in aircraft design to the US. The first US swept wing fighter, the superlative P-86 Sabre (later F-86), flew over a year before the first such British aircraft.

Britain was taking a cautious approach to innovation in naval aviation, not for the first time, and there was a degree of doubt as to the practicality of swept-wing flight from aircraft carriers. The US, on the other hand, had seized on the potential offered by swept wings, even for naval aviation. The radical tailless swept wing Vought F7U Cutlass for the US Navy had flown in 1948, but had not yet landed on a carrier.

The aircraft involved was part of a long and tortuous development programme in which Supermarine struggled for years to get a swept-wing jet into service, making it all the more remarkable that the aircraft achieved a notable world first.

How the Supermarine 510 VV106 came to be the first swept-wing jet to land on an aircraft carrier is part of a lengthy and complex story. This began with Supermarine’s latest attempt to replace the iconic Spitfire, with an aircraft known as the Spiteful – initially a Spitfire with a new, laminar-flow wing but later developed into a new aircraft. When it became apparent that the future of fighters was in jet aircraft, Supermarine mated the new wing to an ellipsoid fuselage designed around the Rolls Royce Nene centrifugal flow turbojet engine. This aircraft, initially known as the ‘Jet Spiteful’ was rejected for the RAF but became the first operational jet fighter for the Fleet Air Arm, the Attacker.

Supermarine 510
Two Supermarine Type 510s were built, based on the fuselage of the Attacker naval fighter jet. VV106 is preserved at the Fleet Air Arm Museum

In 1946, the Air Ministry recognised the performance increases possible with swept wings and commissioned Hawker and Supermarine to build prototypes of existing straight-wing fighter designs with swept mainplanes. The Hawker design, a modified Sea Hawk, was the first to fly by a few days, in December 1948.

Supermarine instigated a detailed investigation of available data on swept wings which at the time was still new technology. After much consideration, a sweep of 40° at 25% chord was selected as the greatest angle that could be sustained without encountering undue problems in low-speed handling. The aerofoil adopted was a 10% thickness/chord laminar flow section developed by the National Physical Laboratory which had a number of beneficial features. These included a narrow trailing-edge angle which had been found to be beneficial at high Mach numbers, a leading-edge sufficiently rounded to permit good low-speed handling, and a maximum thickness at 35% chord. The latter was useful not so much for its aerodynamic properties as the fact that it coincided with the Attacker’s main spar location.

As little was known about particularly low-speed handling characteristics with this wing, Supermarine built integral slots into the leading edge. These were progressively reduced in size as confidence in the design increased, and were eventually removed altogether.

The Supermarine design was known as the Type 510, but it would be developed into the Type 517, Type 528, Type 535 and Type 541 before the aircraft emerged as a production aircraft, the Swift F.1 fighter (which was quickly withdrawn from service in its intended role).

However, in 1948 the Type 510 showed promise. Despite its somewhat piecemeal design, and the shoestring budget it was developed on, the Supermarine aircraft’s performance and handling was comparable to the F-86 in some flight regimes. The lack of powered controls and a variable-incidence tailplane meant handling suffered at high altitude compared with the Sabre. A second prototype was under construction and would fly in March 1950.

In fact, Supermarine was quietly confident in its design by this time and started forming plans to mount an assault on the World Speed Record with the second aircraft, VV119. These plans were shelved in the mounting rush to develop the aircraft for service use though the Type 510’s descendant the Swift would later successfully challenge for the record.

Supermarine test pilots had taken the aircraft to Mach 0.95 within weeks of its first flight, and the Type 510 was capable, with assistance, of just over 670 mph. According to Supermarine’s Chief Test Pilot Mike Lithgow, “with the Nene engine it could not reach this speed in level flight and a slight dive was necessary, but then it could be held for some time.” This was more than 70 mph faster than the standard Attacker and only a whisker slower than the F-86.

Supermarine Attacker wing
The straight, cannon-armed wing of the standard Attacker contasts with the sharply-swept wing of the Type 510 – although the undercarriage was the same

The development of jet fighters was progressing rapidly and by 1950 it was apparent that the standard straight wing types the FAA was beginning to adopt risked being outclassed. Furthermore, developments to aircraft carrier design such as the angled flight deck promised to enable faster aircraft to successfully operate from carriers. The ‘Jet Spiteful’ had been successfully adapted for carrier use, so a logical experiment with the Type 510 was to use it to assess the practicality of swept wing aircraft in this environment.

The Type 510 VV106 was modified over several months in 1950 with standard Attacker undercarriage oleos and arrestor hook. Take-off assistance was also added for security. According to Mike Lithgow: “We were uncertain about the take-off of the 510 from the deck, and to be on the safe side provision was made for two RATOG (rocket assisted take-off gear) units on either side of the fuselage.”

The modified Type 510 flew in September 1950, and spent some time engaged in aerodrome dummy deck landings (‘ADDLs’) at Farnborough. Accounts differ as to when the first carrier flights actually took place – most sources, including Barrie Hygate’s British Experimental Jet Aircraft put the date at 29 December 1950. Mike Lithgow’s book Mach One, however, puts the flights on 8 November.

The flights were made by Lithgow and two naval pilots, Lieutenant Commander Doug Parker and Lieutenant Commander Jock Elliott, from the carrier HMS Illustrious. According to Lithgow: “The trial went exceedingly well until the last take-off. For some reason never satisfactorily explained, possibly an ‘underproof’ RATOG unit, the port wing dropped as Doug Parker became airborne. By the greatest good fortune it struck the flat top of the forward port 4.5 in gun turret. This literally threw him back into level flight, from which he was able to accelerate away in the orthodox and accepted manner.”

The Type 510 had claimed the important ‘first’ and proved beyond doubt that swept wing jets could be operated from a carrier. From this time onward, no straight-wing fighter would again be ordered for the Fleet Air Arm.

VV106 was quickly stripped of its naval accoutrements but the aircraft would continue to innovate. As part of a programme to improve control at higher altitudes, a variable incidence tail was fitted in 1953. However, rather than install a by-now conventional adjustable tailplane, Supermarine opted for an articulated rear fuselage. This moved the entire tail section, including the jetpipe, through +/- 4° and could be controlled by the pilot. This development was the first of its kind. While it was never introduced onto a production aircraft, it was not only successful as a trim device but presaged the later idea of ‘thrust vectoring’. VV106 flew again in this form, and redesignated the Type 517, in September 1953. (Contrary to some reports, VV106 was not designated Type 517 until after its carrier landings).

Supermarine 517 tail
The Supermarine Type 517 tail, including an articulated, variable-incidence rear fuselage. The first jet thrust vectoring? Unusually for a jet, the Type 510/517 retained tailwheel undercarriage

Attacker tail
The swept tail surfaces of the Type 510/517 contrast with the large straight fin and tailplane of the standard Attacker

In fact, the Type 517 may have been the first aircraft to fly with a form of thrust vectoring. A Gloster Meteor had been heavily modified to deflect some of its jet exhaust downwards to assist lift, but the ‘Jet Deflection’ Meteor did not fly until May 1954. In any case, the Meteor system was very different to current thrust vectoring jets like the Lockheed-Martin F-22, which like the Type 517 alter the angle of the jetpipe to ‘steer’ the exhaust flow while manoeuvring. The Supermarine system was used for trim in flight only, but was in essence just a short step away from a system that is currently used to dramatically improve low speed manoeuvrability. It is intriguing to consider what might have been if this development had been pursued further.

In any case, the Type 510 proved that swept wing aircraft could operate from aircraft carriers and can therefore considered the first of a new generation of higher-performance carrier fighters.

VV106 is currently preserved at the Fleet Air Arm Museum at Yeovilton as part of the reserve collection. It is not currently on permanent display, but can be viewed during the annual openings of the reserve collection building, Cobham Hall.

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