The Handley Page HP.88 was a British research aircraft, built in the early 1950s for Handley Page to test the aerodynamics of the Victor

crescent wing The crescent wing is a fixed-wing aircraft configuration in which a swept wing has a greater sweep angle on the inboard section than the outboard, giving the wing a crescent shape. The planform attempts to reduce several unpleasant side-effects o ...

design, and was intended to be a scaled-down version of that aircraft.

Development

The single HP.88 aircraft was designed to Air Ministry Specification E.6/48 as an aerodynamic testbed for the proposed

Handley Page Victor The Handley Page Victor is a British jet-powered strategic bomber developed and produced by Handley Page during the Cold War. It was the third and final '' V bomber'' to be operated by the Royal Air Force (RAF), the other two being the Avr ...

V-bomber. To save time and cost it was decided to base the fuselage on the

Supermarine Attacker The Supermarine Attacker is a British single-seat naval jet fighter designed and produced by aircraft manufacturer Supermarine for the Royal Navy's Fleet Air Arm (FAA). The type has the distinction of being the first jet fighter to enter oper ...

. This was then changed to the Supermarine Swift which had already been redesigned with a swept wing. In the event, the many changes led Supermarine to give the design its own designation as the Supermarine 521. Detail design was contracted to

General Aircraft General Aircraft Limited was a British aircraft manufacturer from its formation in 1931 to amalgamation with Blackburn Aircraft in 1949 to become Blackburn and General. Its main products were military gliders and light transport aircraft. His ...

(GAL) at

Hanworth Aerodrome London Air Park, also known as Hanworth Air Park, was a grass airfield in the grounds of Hanworth Park House, operational 1917–1919 and 1929–1947. It was on the southeastern edge of Feltham, now part of the London Borough of Hounslow. In th ...

, but after GAL merged with Blackburn the work was moved to

Brough Aerodrome Brough Aerodrome was a private use aerodrome located at Brough, East Riding of Yorkshire, England. It is now disused with the last known flight out of the airfield occurring in 2011. The airfield closed in 2013. It is planned that the site ...

and the design was given the Blackburn/ SBAC designation YB-2. The aircraft was allocated military serial ''VX330''. The HP.88 had a 0.36 scaled-down equivalent of the Victor's

and

T-tail A T-tail is an empennage configuration in which the tailplane is mounted to the top of the fin. The arrangement looks like the capital letter T, hence the name. The T-tail differs from the standard configuration in which the tailplane ...

with slab tailplane. However where the Victor had a mid wing, the Type 521 set the wing low on the fuselage. Also, the Victor design continued to be refined, so the HP.88 was no longer representative of the Victor. The HP.88 wing featured inboard trailing-edge flaps, which badly affected trim when deployed. The tailplane was too small to counter the trim change, so a system was developed where the ailerons deflected upwards together to balance the trim forces. The system was wholly automatic with no pilot intervention, and in the event of any failure all surfaces would return to their normal positions. Uprigging the ailerons was a technique used during flutter testing on the second prototype Victor. The fin flutter speed was critically dependent on the steady airload on the tailplane. With both ailerons rigged in the up position the pressure distribution around the wing was altered and hence the trim load required from the tailplane. The Supermarine fuselage was delivered to the

Blackburn Blackburn () is an industrial town and the administrative centre of the Blackburn with Darwen borough in Lancashire, England. The town is north of the West Pennine Moors on the southern edge of the Ribble Valley, east of Preston and north-n ...

factory at Brough, where it was modified and the wing fitted. The completed HP.88 was taken by road to Carnaby near

Bridlington Bridlington is a coastal town and a civil parish on the Holderness Coast of the North Sea in the East Riding of Yorkshire, England. It is about north of Hull and east of York. The Gypsey Race enters the North Sea at its harbour. The 2011 ...

, where it was flown for the first time on 21 June 1951. Testing by Blackburn revealed pitching oscillations at speeds above 230 knots. Modifications to the tailplane gave acceptable behaviour, with only minor oscillation, up to 450 knots (Mach 0.82). The HP.88 was delivered to Handley Page and on 6 August 1951 was flown to

Stansted London Stansted Airport is a tertiary international airport serving London, England, United Kingdom. It is located near Stansted Mountfitchet, Essex, England, northeast of Central London. London Stansted serves over 160 destinations acro ...

for further testing. On 26 August 1951, in preparation for the 1951 SBAC Air Display at Farnborough, the HP.88 carried out a high-speed pass at 300 ft over Stansted, and was seen to start a pitching oscillation before breaking up in mid-air. The "black box" flight recorder subsequently showed pitching accelerations of +/-12g. The cause was traced to a

tailplane A tailplane, also known as a horizontal stabiliser, is a small lifting surface located on the tail (empennage) behind the main lifting surfaces of a fixed-wing aircraft as well as other non-fixed-wing aircraft such as helicopters and gyropla ...

control system servo instability involving a bob-weight that had been added as a safety measure.Bombers of the West, Bill Gunston 1997, Ian Allan Ltd., SBN 684-13623-6, p.84 The HP.88 had only flown 14 hours in 26 sorties over a lifetime of just 36 days, and had little time to gather useful information, but the loss of the aircraft was of little significance to the V bomber project; two prototype Victors were already nearing completion by the time of the HP.88's first flight.

Specifications (HP.88)

References

Notes

Bibliography

* Barnes, C. H. ''Handley Page Aircraft Since 1907''. London: Putnam & Company, Ltd., 1987. . *Buttler, Tony and Jean-Louis Delezenne. ''X-Planes of Europe: Secret Research Aircraft from the Golden Age 1946-1974''. Manchester, UK: Hikoki Publications, 2012. * Clayton, Donald C. ''Handley Page, an Aircraft Album''. Shepperton, Surrey, UK: Ian Allan, 1969. . * Hygate, B.; ''British experimental jet aircraft'', Argus, 1990, Pages 106-112. * * Taylor, John W.R. ''Jane's Pocket Book of Research and Experimental Aircraft'', London, Macdonald and Jane's Publishers Ltd, 1976. . {{British military aircraft since World War II 1950s British experimental aircraft HP.088

Development

Specifications (HP.88)

See also

References

Notes

Bibliography