Sometimes an aircraft is built for mundane reasons, like the progressive development of a series – the Douglas DC-7c airliner would be a prime example; sometimes out of sheer desperation – the Miles M.20 fighter prototype, constructed at the height of the Battle of Britain seems to fit this bill; but rarely, very rarely, is an aircraft built as the result of an argument!
English Electric’s ‘weaponization’ of their P.1 supersonic research aircraft, into a Mach 2 interceptor (the Lightning), only survived because the process was too far along for the U.K.’s appalling 1957 Defence White Paper – authored by Duncan Sandys, who should have been sacked on the spot for single-handedly destroying the British military aircraft industry – to take effect. I have written in an earlier piece, how there were constant arguments about the whole project, and how it came close to cancellation on several occasions. One rather contentious point involved the wing. The Royal Aeronautical Establishment disagreed with the projected figures from English Electric, who maintained that even with a wing of 60 degrees sweep, the intended fighter would perform quite satisfactorily at the relatively low-speeds encountered during the landing phase of flight.
Much to the displeasure of English Electric (who stood by their data), in 1950 the RAE persuaded the Air Ministry to issue Specification ER.100, to cover the construction of one research aircraft to explore the low-speed handling characteristics of highly-swept wings in a jet aircraft. The wing planform was to closely resemble that of the projected English Electric fighter, but would be capable of being mounted at various angles of sweep (adjusted on the ground, not in flight) and, as an added bonus, would have either a T-tail, mounted on top of the vertical fin, or a low-set tailplane, as was being used by the E.E. P.1 research aircraft, which had been flying since 1954. The contract, ’6/Aircraft/5347/CB.7(a)’ was granted to Short Brothers & Harland Ltd, of Belfast, Northern Ireland on 2nd August, 1950, and the RAF allocated the serial ‘WG768′ to what became known as the Short SB.5.
The fuselage construction was conventional, stressed skin aluminium alloy, but made in such a way as that the whole rear fuselage could be detached. Also, the wing had alloy leading edges, but plywood skinning behind that. The undercarriage was fixed (most unusual in a jet aircraft) as the maximum speed wasn’t expected to be above 400 mph (403mph, in actuality). The wings could be removed and refitted at 50°, 60° or 69° sweep between different phases of the mission. Despite having a small triangular tailplane fitted at the top of the raked fin, it was found that the only practical way to compare that to a low-set tailplane was to construct a whole new rear fuselage, then fit that unit when the time came.
Power was supplied by a Rolls-Royce Derwent 8 centrifugal compressor turbojet of 3,600 lbs thrust; it turned out that this left the aircraft somewhat underpowered. The completed aircraft was sent via ship and road transport to the Aircraft & Armament Experimental Establishment at Boscombe Down, Wiltshire. After re-assembly, it made its first flight on the 2nd December, 1952, piloted by Tom Broooke-Smith. The initial configuration was with the wing at 50°, with the triangular tailplane on top of the fin. Changes came in 1953, when following a spell in the Short’s factory in Belfast, WG768 emerged with its wings set at 60°; it was at this time that a photograph was released to the public, the SB.5 being described as ‘a slow-speed research aircraft….the machine abounds in unorthodox features’. It was in August 1953, that the famous WW2 ‘ace’ and test pilot, Wing Commander Roland Prosper “Bee” Beamont CBE, DSO & Bar, DFC & Bar, who was in charge of the English Electric P.1 test programme, first flew the S.B.5. “Bee” was apparently less than impressed with the tail, as it was set up at the time. Tom Brooke-Smith flew the SB.5 at the annual Society of British Aerospace Companies Airshow at Farnborough, where it demonstrated excellent manoeuverability and low-speed handling with the 60° wing. Once again a trip to Belfast gave rise to a new configuration, this time with the alternate rear fuselage and low-mounted tailplane.
Starting in 1954, there began a couple of years handling work with the Royal Aircraft Establishment, first at Farnborough, and then RAE Bedford; a final configuration change was initiated in 1958, when the aircraft was dismantled. The fuselage was placed on a 40 foot long RAF ‘Queen Mary’ semi-trailer (built by Taskers Trailers Ltd), and the SB.5 wings on a 33 foot long Lancaster trailer, and driven to Preston, where the road convoy embarked on the M.V. ‘Bardic Ferry’ and departed for Belfast once more.
Arriving at Short’s, the SB.5 was virtually rebuilt. The lack of power was addressed by swapping the Derwent for a Bristol Siddeley Orpheus BE.26 axial-flow turbojet of 4,520 lbs thrust to match the new 69° sweep wing – this made it the most highly swept wing flying at this time. A Martin-Baker ‘zero-level’ ejection seat was fitted along with extra cockpit instrumentation. By the time the SB.5 arrived back at RAE Bedford, it had also received a new coat of paint – bright blue! The last phase of the aircraft’s testing life was probably the most significant. In May 1964, ‘Flight’ magazine, described it thus, ‘The venerable SB.5, having long ago finished its low-speed work for the Lightning, is once again active in the hands of Flight Lieutenant Farley. The tufted, 69° sweep wing is investigating leading edge flow patterns as part of the low-speed testing for the Concord wing’.
There was nearly a radical end to the aircraft’s career; it was offered to the Australian Aeronautical Research Laboratory, but, finally, it was decided that the SB.5 would not be useful ‘Down Under’. As an alternative, in 1965, it was sent to the Empire Test Pilots School at Boscombe Down, to enable students to gain low-speed handling experience in highly-swept aircraft.
When finally withdrawn from use in 1967, the SB.5 was slated for eventual display at the RAF Museum, but was flown to RAF Finningley and placed in storage for a period; whilst there it received the ‘silver over very dark blue’ finish you can see above. After shuttling between various RAF units, it finally ended up in the ‘Test Flight’ section of the RAF Museum at Cosford; you can just make out the triangular fin of the ‘spare rear fuselage’ displayed behind the SB.5.
As Wing Commander Beamont had predicted, the SB.5 was a waste of time, as the data English Electric provided was proved right and the RAE's suggestion proved wrong, in that the P.1′s low-set tailplane turned out to be the correct solution. However, the aircraft DID render valuable service to the Concord testing program, so all was not lost.
One more thing. The British have a peculiar talent for choosing inappropriate names for their aircraft. Who can forget that the Spitfire was going to be called the Shrew, for example? Then there was the whole business about the Hawker Hedgehog! When the SB.5 was announced there was a debate over what the ‘fighter’ that was to be developed from the P.1B was to be called. Here are some of the names that were suggested (and published!) Arrow, Assegai, Fiend, Wraith, Terror, Excalibur, Champion, Strongbow, Crossbow, Virago, Warrior and Paladin. I can only suggest that someone had a Royal Navy fixation, as all but ONE of these were names – at one time or another – of RN ships. Not only that, but one is also the name of a model of Rolls-Royce, and yet another the name of a brand of strong cider! Thank goodness they finally selected the English Electric Lightning!
The Short SB.5 – a initial failure, but very useful in the end.