OS 1 / H.Cowin - X-Planes

Frederick Handley Page, later to be knighted, was among the first to realise the advantages of the slotted wing, a feature that allowed the aircraft either to fly slower for a given weight, or to lift-off at a higher weight without stalling - avoiding that frequently literal sinking feeling when an aircraft quits flying. Following a series of patents granted Handley Page in late October 1919, his company acquired this war-surplus Puma-engined DH 9 in February 1920, modifying it as the Handley Page HP 17, with leading edge slots fitted to both upper and lower wings. Seen here in its earliest form, a longer, stronger set of landing gear legs were later fitted, in April 1920. These trials had an enormous impact on the aviation world, with the HP 17 demonstrating a 30% improvement in the peak amount of wing lift produced by the use of slots.

Flight 1921-12 / Flight

FIRST FULL-SCALE EXPERIMENT WITH HANDLEY PAGE SLOTTED WING: The "D.H.9" fitted with slotted wings.

Aeroplane Monthly 1979-08 / Cricklewood /Gone but not forgotten/ (4)

Регистрационный номерRegistry number: H9140   [2]

The slotted H.P.17 was a much-modified D.H.9, H9140, purchased by Handley Page from the Aircraft Disposal Board in February 1920. It was fitted with full-span slats on both upper and lower wing leading edges and the undercarriage was later lengthened by 12in. The H.P.17 was flown against a standard D.H.9 in comparative tests, and both aircraft are seen here at Cricklewood on October 21, 1921. Frederick Handley Page is second from left.

Другие самолёты на фотографии: Another planes on the photo: De Havilland D.H.9B / D.H.9C - ВеликобританияUnited Kingdom - 1919

Flight 1920-10 / Flight

Регистрационный номерRegistry number: H9140   [2]

THE HANDLEY PAGE WING: The Airco 9 fitted with the H.P. device. Inset the machine in flight. The false leading edge and its supporting brackets can be clearly seen

Flight 1921-12 / Flight

FIRST FULL-SCALE EXPERIMENT WITH HANDLEY PAGE SLOTTED WING: A close-up view of the arrangement of the slot.

Aeroplane Monthly 1986-02 / K.Desmond - H.P. (1)

D.H. and H.P. This historic photograph was taken at Cricklewood on October 21, 1920 and shows Capt Geoffrey de Havilland and Frederick Handley Page standing in front of a D.H.9 fitted with H.P. leading edge slats, which improved low-speed lift, landing and safety.

Flight 1921-11 / Flight

THE HANDLEY PAGE SLOTTED WING TESTED AS A MONOPLANE: 1. The complete machine. 2. Slot closed and aileron normal. 3. Slot open and aileron normal. 4. Slot open and aileron down.
The photographs show a Handley Page slotted wing mounted on the fuselage of a D.H.9A. The machine is comparatively crudely made, but it has served to demonstrate that the scale effect is normal for a slotted wing, and also that the slotted ailerons fitted are effective up to the angle of maximum lift. A more refined machine is now being built, and the full-scale experiments will then be continued with the latest forms of slots.