Addyman

E.T.W. Addyman

History

Erik Thomas Waterhouse Addyman, born on 30 April 1889 in Starbeck, Knaresborough, Yorkshire, the son of James Wilson Addyman and Edith Constance Addyman (née Wilkin), was another of those larger than life characters that seemed to be part of early British aviation. His father, a solicitor, was Norwegian Vice-Consul (hence Erik not Eric). He trained as an engineer at Kitson's College in Leeds. During the First World War he initially worked at the Portsmouth School of Mines researching depth charges and later he moved to Dumhries, to the Arrol Johnson Engineering Works, during which time he was awarded several patents associated with improvements to the internal combustion engine.

In July 1920, Erik married Evelyn Mary Fisher, having three sons, James Cadwallader, Oscar Thomas and Peter Vincent. Later in the 1920s he moved back to Starbeck and used his engineering background to build at least five motor cars. He also was a keen pot-holer and climber and was a reserve in the Mallory-Irvine Everest attempt in 1924.

In January, 1930, The Harrogate Aircraft Club was formed with Addyman as the Hon. Secretary. Their first construction was a Dickson Primary, built by and for the use of members and it was in this machine that Addyman suffered a serious accident on February 14th, 1932, breaking both legs and requiring the lower part of his right arm to be amputated.

Despite this handicap, Addyman was soon to design his own gliders, the Zephyr sailplane in 1933 followed by the Standard Training Glider in 1934. He also intended to fit an Anzani to an S.T.G. type but although work was begun in 1936, it was not completed.

Erik Thomas Waterhouse Addyman died in Harrogate, Yorkshire, on 24 January 1963.

Company References

The Yorkshire Post, Aug 19, 1989
The Classic MotorCycle November 2015

Project Data

Name	Alternative Name(s)	Year	Status	Qty	Description	References
Zephyr		1933	Proto	1	1S glider	1,3
S.T.G.	Standard Training Glider	1934	Prdn	2	1S glider	1
Ultra-light		1936	Pro(n)	1	1S ultralight	1,2

Project References

British Gliders and Sailplanes 1922-1970, Norman Ellison (Adam and Charles Black, 1970)
British Homebuilt Aircraft Since 1920, Ken Ellis (Merseyside Aviation Society, 1975 and 1979)
Sailplane and Glider 28 Apr 1933

Production Details and Type Description

Zephyr
Single seat, light wind sailplane, combining a wing of modest aspect ratio with a nacelle cockpit and an open truss girder fuselage of the kind more common on primary gliders. It was a wooden-structured, largely fabric-covered aircraft. The two-spar wing had a straight leading edge and constant chord out to a little over half span, where the trailing edges of the ailerons, hinged at a slight angle to the spar, curved inwards to the wingtips. It was braced from above with pairs of wires from the spars to a central, inverted V-strut pylon and below by wires to the lower nacelle longerons. There were no flaps or air brakes. The central wing rib was continued rearward with the upper member of the open, flat, converging Warren girder fuselage, whose lower member joined the keel of the plywood- and fabric-covered nacelle just aft of the wing trailing edge. This placed the open single cockpit just forward of the wing leading edge. A central keel skid formed the main undercarriage, with assistance from a tail bumper. A narrow-span, triangular tailplane, wire braced above and below, carried longer-span elevators with rounded tips and a cut-out for the deep, rounded rudder hinged to small, triangular fin.

Addyman Zephyr Specification
Span	Length	Height	Wing Area	Empty Wt	Max AUW
41 ft 9 in	18 ft 6 in		195 sq ft	185 lb
12.73 m	5.64 m		18.12 m2	84 kg

One machine only; first flown in 1933, it was to have joined the Northern Aircraft Preservation Society as BAPC.59, but destroyed before delivery.

S.T.G
Single seat primary glider for low cost basic training. It was a simple, wooden, aerodynamically unrefined aircraft with a relatively low aspect ratio wing, a cockpit nacelle under it and a flat open truss girder fuselage aft. The unswept wing had parallel chord with blunt tips and was built around two spars. There were no flaps or airbrakes. Above the wing landing wires ran from about mid-span on each wing from the spars to the top of a centrally mounted inverted V-strut; below, similarly arranged flying wires ran to the lower nacelle longerons. Attached immediately behind the single open cockpit headrest at the forward wing spar, the nacelle extended rearwards only to the wing trailing edge, suspended from an inverted V pair of struts to the rear spar. A landing skid extended over most of the length of the nacelle. Aft of the nacelle, the fuselage was an uncovered converging Warren girder structure carrying the tail surfaces and braced laterally by wires to the mid-span wing points. The fin was very small but carried an almost rectangular rudder which extended to the fuselage keel via a cut-out in the elevators. The tailplane was straight tapered, with a swept leading edge. A wire tail bumper completed the undercarriage.

Addyman S.T.G. Specification
Span	Length	Height	Wing Area	Empty Wt	Max AUW
37 ft 6 in	19 ft 4 in		187 sq ft
11.43 m	5.89 m		17.37 m2

Two built at Harrogate and flew for the first time in June 1934. Both survive as BAPC.14 and BAPC.15.

Ultralight
One aircraft, developed from the S.T.G, to have been fitted with an Anzani powerplant, but never completed; survives as BAPC.16.

Production References

British Gliders and Sailplanes 1922-1970, Norman Ellison (Adam and Charles Black, 1970)
British Homebuilt Aircraft Since 1920, Ken Ellis (Merseyside Aviation Society, 1975 and 1979)

Page Revision History

Revised at Version 2.1.1

Corrected typographical errors.

Revised at Version 2.0.0

Added Type Description and Specification details.