The Handley Page Type D or H.P.4 was a single seat, single engined tractor

Tractor configuration

thumb|right|[[Evektor-Aerotechnik|Aerotechnik EV97A Eurostar]], a tractor configuration aircraft, being pulled into position by its pilot for refuelling....

 monoplane

Monoplane

A monoplane is a fixed-wing aircraft with one main set of wing surfaces, in contrast to a biplane or triplane. Since the late 1930s it has been the most common form for a fixed wing aircraft.-Types of monoplane:...

, the first Handley Page design to fly for more than a few hops. Only one was built.

Development

The Type D was the third and last of Handley Page's early single seat monoplanes (the Type B being a biplane). It was a close relative of the Type A, which crashed on its first turn, and the Type C which did not fly at all. Like them the Type D used the wing patented by José Weiss that promised, but failed to deliver, automatic lateral stability. Its structure was based on a rigid inner section, built with four spars and standard ribs with a flexible outer section carried on ribs attached fanwise from the end of the spars in a bird-like fashion. The wing was braced by wires from a tall, narrow inverted V kingpost, lifting loads being carried by symmetric bracing to a matching V post under the fuselage. This latter structure also carried the two wheel single axle undercarriage and a long central skid to prevent nosing over and to hold the tail clear of the ground. After the Type A crash, Handley Page had added wing warping for lateral control to the Type C. The Type D also used this system, with a steering wheel pulling on wires to the mid-wing via the kingpost. The horizontal tail was an approximately 60^o delta with rounded tips; most of the surface moved to form the single-piece elevator and carried the rudder post and split (above and below the elevator) rudder, so all the control surfaces moved together as a cruciform piece. The elevator was operated by pushing or pulling the lever mounted steering wheel and the rudder by a "foot tiller". There was no fixed fin.

The Type D was built for the 1910 Olympia Aero Show and appeared there with a borrowed 35 hp (26 kW) liquid cooled Green engine mounted tractor fashion in a semi-monocoque mahogany planked fuselage. This engine was not powerful enough to get the Type D into the air and a new canvas covered fuselage had to be built to house the 50 hp (37 kW) Isaacson from the Type C.

It was entered into the Daily Mail

Daily Mail

The Daily Mail is a British daily middle-market tabloid newspaper owned by the Daily Mail and General Trust. First published in 1896 by Lord Northcliffe, it is the United Kingdom's second biggest-selling daily newspaper after The Sun. Its sister paper The Mail on Sunday was launched in 1982...

circuit of Britain race, starting on 22 July 1911 but crashed at the end of its first flight on 15 July. Appearing after repairs in yellow varnish, it was named The Antiseptic by Handley Page's new test pilot, Edward Petre, after the tincture of iodine commonly used on cuts in those days. In the Handley Page factory at Barking, north east London

Barking

Barking is a suburban town in the London Borough of Barking and Dagenham, in East London, England. A retail and commercial centre situated in the west of the borough, it lies east of Charing Cross. Barking was in the historic county of Essex until it was absorbed by Greater London. The area is...

 it was often called the Yellow Peril after the current nickname for Gold Flake cigarettes. It flew several times from a rented part of a sports field at Fairlop

Fairlop

Fairlop is a district of Ilford in the London Borough of Redbridge, just north of Barkingside. It mainly consists of fields, forestry and open land providing space for sport/ activity centres , a few houses, farmland and watersport/ fishing lakes . It also has a tube station....

, six miles north of Barking, before Handley Page decided to concentrate on two seaters with better sales prospects. Nonetheless, the Type D was the first Handley Page designed aircraft to fly successfully. In the retrospective redesignations of 1924 the Type D became the H.P.4.

Specifications (Isaacson)