The Radab Windex is a family of

Swedish Swedish or ' may refer to: Anything from or related to Sweden, a country in Northern Europe. Or, specifically: * Swedish language, a North Germanic language spoken primarily in Sweden and Finland ** Swedish alphabet, the official alphabet used by ...

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 planes. A monoplane has inherently the highest efficiency and lowest drag of any wing co ...

, single-seat aerobatic 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 flight ...

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 Wind tunnels are large tubes with air blowing through them which are used to replicate the interaction between air and an object flying through the air or moving along the ground. Researchers use wind tunnels to learn more about how an aircraft ...

. 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 clo ...

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 The Paris Air Show (french: Salon international de l'aéronautique et de l'espace de Paris-Le Bourget, Salon du Bourget) is a trade fair and air show held in odd years at Paris–Le Bourget Airport in north Paris, France. Organized by the French ...

. 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 compo ...

and fibreglass. The aircraft is fully aerobatic and stressed to +9/-6 g. The span wing has carbon fibre spars and is of a semi-tapered planform. The wing employs a custom Radab KTH-FFA 17% thickness airfoil 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 "Sportfl ...

-style upper surface air brakes and 22.5% chord flaps for glidepath control. The König SC-430

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 (up and down movements) of the piston during one power cycle, this power cycle being completed in one revolution of ...

three-cylinder engine is mounted in

tractor configuration In aviation, the term tractor configuration refers to an aircraft constructed in the standard configuration with its engine mounted with the propeller in front of it so that the aircraft is "pulled" through the air. Oppositely, the pusher co ...

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 ''fuselé'' "spindle-shaped") is an aircraft's main body section. It holds crew, passengers, or cargo. In single-engine aircraft, it will usually contain an engine as well, although in some amphibious aircraf ...

, 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 is the largest city in Lubusz Voivodeship, located in western Poland, with 140,403 inhabitants (2021). Zielona Góra has a favourable geographical position, being close to the Polish-German border and on several international road ...

Poland Poland, officially the Republic of Poland, is a country in Central Europe. It is divided into 16 administrative provinces called voivodeships, covering an area of . Poland has a population of over 38 million and is the fifth-most populou ...

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

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ...

with the

Federal Aviation Administration The Federal Aviation Administration (FAA) is the largest transportation agency of the U.S. government and regulates all aspects of civil aviation in the country as well as over surrounding international waters. Its powers include air traffic ...

. 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 flame-resistant meta-aramid material developed in the early 1960s by DuPont and first marketed in 1967. Properties Nomex and related aramid polymers are related to nylon, but have aromatic backbones, and hence are more rigid and mo ...

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 König SC-430 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, s ...

. The engine has electric starting and weighs .

Specifications (1200C)

References

External links