The Radab Windex is a family of Swedish

high-wing A monoplane is a fixed-wing aircraft configuration with a single mainplane, in contrast to a biplane or other types of multiplanes, which have multiple wings. A monoplane has inherently the highest efficiency and lowest drag of any wing config ...

, single-seat

aerobatic Aerobatics is the practice of flying maneuvers involving aircraft attitudes that are not used in conventional passenger-carrying flights. The term is a portmanteau of "aeroplane" and "acrobatics". Aerobatics are performed in aeroplanes and gl ...

gliders and

motor glider A motor glider is a fixed-wing aircraft that can be flown with or without engine power. The FAI Gliding Commission Sporting Code definition is: a fixed-wing aerodyne equipped with a means of propulsion (MoP), capable of sustained soaring flig ...

s that was designed by Sven Olof Ridder and produced initially by Radab and later by WindexAir AB as a kit for amateur construction.Bertrand, Noel; Rene Coulon; et al: ''World Directory of Leisure Aviation 2003-04'', page 60. Pagefast Ltd, Lancaster OK, 2003. ISSN 1368-485X

Design and development

The initial design was the unpowered model 1100. This was followed by the present production 1200C motorglider. The project started off in 1980 as a hobby design between Sven-Olof Ridder and Harald Undén, who later founded Radab to produce the design. By 1983 they had developed the custom airfoil section and tested it in a

wind tunnel A wind tunnel is "an apparatus for producing a controlled stream of air for conducting aerodynamic experiments". The experiment is conducted in the test section of the wind tunnel and a complete tunnel configuration includes air ducting to and f ...

. The first unpowered 1100 model flew in 1985, but the following year, as they geared up for kit production the factory burnt down, including all the

fibreglass Fiberglass (American English) or fibreglass ( Commonwealth English) is a common type of fiber-reinforced plastic using glass fiber. The fibers may be randomly arranged, flattened into a sheet called a chopped strand mat, or woven into glass c ...

molds that they had built. Only two 1200 C aircraft kits had been produced before the molds were destroyed. One of these was completed in time to be flown at the 1987 Paris Airshow. By 1990 the molds had been replaced and the first new 1200 C was completed. The first amateur-built Windex was completed from a kit in 1996. By 1999 WindexAir AB had assumed production from Radab. The 1200 C is built from a combination of

carbon-fiber-reinforced polymer Carbon fiber-reinforced polymers (American English), carbon-fibre-reinforced polymers ( Commonwealth English), carbon-fiber-reinforced plastics, carbon-fiber reinforced-thermoplastic (CFRP, CRP, CFRTP), also known as carbon fiber, carbon comp ...

and fibreglass. The aircraft is fully aerobatic and stressed to +9/-6 g. The span wing has carbon fibre

spars SPARS was the authorized nickname for the United States Coast Guard (USCG) Women's Reserve. The nickname was derived from the USCG's motto, "—"Always Ready" (''SPAR''). The Women's Reserve was established by law in November 1942 during Wor ...

and is of a semi-tapered planform. The wing employs a custom Radab KTH-FFA 17% thickness

airfoil An airfoil (American English) or aerofoil (British English) is a streamlined body that is capable of generating significantly more Lift (force), lift than Drag (physics), drag. Wings, sails and propeller blades are examples of airfoils. Foil (fl ...

and features both

Schempp-Hirth Schempp-Hirth Flugzeugbau GmbH is a glider manufacturer based in Kirchheim unter Teck, Germany. History Martin Schempp founded his own company in Göppingen in 1935, with the assistance of Wolf Hirth. The company was initially called "Sport ...

-style upper surface air brakes and 22.5% chord flaps for glidepath control. The

König SC-430 König (; ) is the German word for "king". In German and other languages applying the umlaut, the transliterations ''Koenig'' and ''Kœnig'', when referring to a surname, also occur. As a surname in English, the use of ''Koenig'' is usual, and som ...

two-stroke A two-stroke (or two-stroke cycle) engine is a type of internal combustion engine that completes a power cycle with two strokes of the piston, one up and one down, in one revolution of the crankshaft in contrast to a four-stroke engine which re ...

three-cylinder engine is mounted in

tractor configuration In aviation, a tractor configuration is a propeller-driven fixed-wing aircraft with its engine mounted with the propeller in front, so that the aircraft is "pulled" through the air. This is the usual configuration; the pusher configuration ...

and has a variable-pitch, fully feathering propeller. When it was in production the Windex 1200 C was supplied in three kits,

fuselage The fuselage (; from the French language, French ''fuselé'' "spindle-shaped") is an aircraft's main body section. It holds Aircrew, crew, passengers, or cargo. In single-engine aircraft, it will usually contain an Aircraft engine, engine as wel ...

, wings and engine and propeller.

Operational history

In 1991 the prototype was flown at the FAI World Glider Aerobatic Championships held at

Zielona Góra Zielona Góra (; ''Green Mountain''; ) is the largest city in Lubusz Voivodeship, located in western Poland, with 140,403 inhabitants (). The region is closely associated with vineyards and holds an annual Zielona Góra Wine Fest, Wine Fest. Zie ...

Poland Poland, officially the Republic of Poland, is a country in Central Europe. It extends from the Baltic Sea in the north to the Sudetes and Carpathian Mountains in the south, bordered by Lithuania and Russia to the northeast, Belarus and Ukrai ...

, winning two bronze medals. In August 2011 there were four Windex motor gliders and one glider

registered Registered may refer to: * Registered mail, letters, packets or other postal documents considered valuable and in need of a chain of custody * Registered trademark symbol, symbol ® that provides notice that the preceding is a trademark or service ...

in the

United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 ...

with the

Federal Aviation Administration The Federal Aviation Administration (FAA) is a Federal government of the United States, U.S. federal government agency within the United States Department of Transportation, U.S. Department of Transportation that regulates civil aviation in t ...

. All are in the '' Experimental - Amateur-built'' category.

Variants

;1100 :Initial prototype motor-glider version, powered by a Limbach engine, flying for the first time in the summer of 1985. ;1200:Production version built using

Nomex Nomex is a trademarked term for an inherently flame-resistant fabric with meta-aramid chemistry widely used for industrial applications and fire protection equipment. It was developed in the early 1960s by DuPont and first marketed in 1967. ...

honeycomb, with a T-tail and increased span wings of the same area. Powered by a Windex 300 3-cyl. two-stroke engine. ;1200 C :Later production version, with a

engine mounted midway on the

vertical stabilizer A vertical stabilizer or tail fin is the static part of the vertical tail of an aircraft. The term is commonly applied to the assembly of both this fixed surface and one or more movable rudders hinged to it. Their role is to provide control, sta ...

. The engine has electric starting and weighs .

Specifications (1200C)

References

External links