View source for Addyman Zephyr

{{Short description|One-off, British single seat sailplane, 1933}}
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{{Use dmy dates|date=February 2018}}
{{Use British English|date=February 2018}}
{|{{Infobox Aircraft Begin
 | name=Zephyr
 | image=
 | caption=
}}{{Infobox Aircraft Type
 | type=Single-seat [[glider (sailplane)|sailplane]]
 | national origin=[[United Kingdom]]
 | manufacturer=E. T. W. Addyman at [[Harrogate]]
 | designer=E. T. W. Addyman
 | first flight=1933
 | introduced=
 | retired=
 | status=
 | primary user=
 | more users= <!--Limited to three in total; separate using <br /> -->
 | produced= <!--years in production-->
 | number built=1
 | program cost= <!--Total program cost-->
 | unit cost= <!--Incremental or flyaway cost for military or retail price for commercial aircraft-->
 | developed from= 
 | variants with their own articles=
}}
|}

The '''Addyman Zephyr''' was a one-off, single-seat [[Glider (sailplane)|sailplane]] designed and built by Erik Addyman in the [[United Kingdom|UK]] for his own use in the 1930s.
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==Design==

Erik Addyman designed and built the single-seat Zephyr, his first design, in 1933.  It was intended as a light wind sailplane,<ref name=Horse/> combining a wing of modest aspect ratio with a nacelle cockpit and an open truss girder fuselage of the kind more common on [[primary glider]]s.  It was a wooden-structured, largely [[aircraft fabric covering|fabric]]-covered aircraft.<ref name=Ellison/>

The two-[[spar (aviation)|spar]] wing had a straight [[leading edge]] and constant [[chord (aircraft)|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 [[flap (aircraft)|flaps]] or [[Air brake (aircraft)|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 [[Landing gear|undercarriage]], with assistance from a tail bumper. A narrow-span, triangular [[tailplane]], wire braced above and below, carried longer-span [[elevator (aircraft)|elevators]] with rounded tips and a cut-out for the deep, rounded [[rudder]] hinged to small, triangular fin.<ref name=Ellison/>

The Zephyr flew for the first time in 1933.<ref name=Ellison/>

==Operational history==
Only one Zephyr was built.<ref name=Ellison/>  Based at [[Harrogate]],<ref name=Ellis22/><ref name=Zephyr/> where Addyman was honorary secretary of the Aircraft Club, it was often launched with a tow from a horse.<ref name=Horse/> He flew it from many fields in central and north-western [[England]] up to the early part of [[World War II]];<ref name=Ellison/>  from 1940 there was a government ban on recreational glider flying.  The Zephyr seems not to have flown again,<ref name=Ellison/> though substantial parts of it still (2010) exist in store.<ref name=Ellis22/>
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==Specifications==
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|crew=1
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<!--==Notes==-->

==References==
{{reflist|refs=

<ref name=Ellison>{{cite book |title= British Gliders and Sailplanes|last=Ellison|first=Norman| year=1971|publisher=A & C Black Ltd|location=London |isbn=978-0-7136-1189-2|page=79}}</ref>

<ref name=Ellis22>{{cite book |title= Wrecks & Relics|last=Ellis|first=Ken| year=2010|edition=22|publisher=Crecy |location=Manchester |isbn=978-0-85979-150-2|page=265}}</ref>

<ref name=Horse>{{cite journal|date=March 1934 |title=Horse-towed flight |journal=Sailing and Gliding |volume=5 |issue=3 |pages=34 |url=http://www.lakesgc.co.uk/mainwebpages/Sailplane%20&%20Glider%201930%20-%201955/volume%205%20No.%203%20Mar%201934.pdf |url-status=dead |archive-url=https://web.archive.org/web/20110930180132/http://www.lakesgc.co.uk/mainwebpages/Sailplane%20%26%20Glider%201930%20-%201955/volume%205%20No.%203%20Mar%201934.pdf |archive-date=2011-09-30 }}</ref>

<ref name=Zephyr>{{cite journal|date=March 1933 |title=News from the Clubs - a light wind sailplane |journal=Sailing and Gliding |volume=4 |issue=8 |pages=93 |url=http://www.lakesgc.co.uk/mainwebpages/Sailplane%20&%20Glider%201930%20-%201955/volume%204%20No.%208%20Apr%2028%201933.pdf |url-status=dead |archive-url=https://web.archive.org/web/20110930180017/http://www.lakesgc.co.uk/mainwebpages/Sailplane%20%26%20Glider%201930%20-%201955/volume%204%20No.%208%20Apr%2028%201933.pdf |archive-date=2011-09-30 }}</ref>

}}
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[[Category:1930s British sailplanes]]
[[Category:Aircraft first flown in 1933]]