The Jonker JS-1 Revelation is a

glider Glider may refer to: Aircraft and transport Aircraft * Glider (aircraft), heavier-than-air aircraft primarily intended for unpowered flight ** Glider (sailplane), a rigid-winged glider aircraft with an undercarriage, used in the sport of gliding ...

built of

glass-fibre 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 clot ...

carbon fibre 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

Kevlar Kevlar (para-aramid) is a strong, heat-resistant synthetic fiber, related to other aramids such as Nomex and Technora. Developed by Stephanie Kwolek at DuPont in 1965, the high-strength material was first used commercially in the early 1970s a ...

. It is available with an 18-metre span for the 18 metre class or a 21-metre span for the Open class. The manufacturer is

Jonker Sailplanes Jonker Sailplanes is a glider manufacturer based in Potchefstroom, South Africa. History Uys Jonker and his brother, Attie Jonker founded Jonker Sailplanes in 2004. Products The following aircraft are in production or under development * Jo ...

Potchefstroom Potchefstroom (, colloquially known as Potch) is an academic city in the North West Province of South Africa. It hosts the Potchefstroom Campus of the North-West University. Potchefstroom is on the Mooi Rivier ( Afrikaans for "pretty ri ...

South Africa South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring coun ...

, founded in 2004 by two brothers, Attie and Uys Jonker. The structural and chief designer is Attie Jonker, while the airfoil and main aerodynamic features were developed by Johan Bosman in co-operation with the

Delft University of Technology Delft University of Technology ( nl, Technische Universiteit Delft), also known as TU Delft, is the oldest and largest Dutch public technical university, located in Delft, Netherlands. As of 2022 it is ranked by QS World University Rankings among ...

18 metre versions

The wing has full-span flaperons, an elliptical planform and uses winglets. It is in 4 pieces, each tip is 1.5 metres. Two novel features are: * a double-hole blowing/suction system in the wings to minimise drag. The two rows of blow holes on the lower surface prevent turbulent flow at specific locations for different flap settings, thus reducing drag * a

jet engine A jet engine is a type of reaction engine discharging a fast-moving jet (fluid), jet of heated gas (usually air) that generates thrust by jet propulsion. While this broad definition can include Rocket engine, rocket, Pump-jet, water jet, and ...

for the self-sustaining version. A self-launching version was considered but it was decided that the fuselage would require extensive structural modification. The first flight of the JS-1 was on 12 December 2006. Series production then started and up to July 2012 about 34 had been produced Attie Jonker won the 18 metre class South African National Championship in 2008 with a JS-1 Revelation.

21 metre version

A new version, JS1C-21m, with 3 metre wing-tips, which increase the span to 21 metres, has been developed. The first flight was on 22 March 2012. Because of the higher wing loads and increased maximum take-off mass of 720 kg (increased from 600 kg), the wing/wingtip junction has been redesigned including stronger wing spar caps and thicker wing-tip spars. All future JS1 Revelations will be compatible with the optional 21m wing-tips. The new wing-tips have water tanks each with a capacity of 17 litres of ballast which can be jettisoned separately from the main wing and fin tanks. Theoretical performance gives a claimed best glide of around 1:60 and, with the maximum wing loading of 58.7 kg/m2 and the polar remaining flat at high cruise speeds, the manufacturers state that it is competitive at the highest level with other Open Class gliders. The results (2nd, 3rd and three other places in the top ten in the 2014

World Gliding Championships The World Gliding Championships (WGC) is a gliding competition held every two years or so by the FAI Gliding Commission. The dates are not always exactly two years apart, often because the contests are sometimes held in the summer in the Southern ...

Open ClassNote that maximal take off mass of JC-1C's (720kg) was significantly lower than the class limit of 850kg, placing JC-1C's at a theoretical disadvantage) supports this assertion.Official results of 2014 FAI World Gliding Championships in Leszno, Poland
retrieved on 13 Aug 2014

EASA certification

The JS1-C is certificated in Europe by

M&D Flugzeugbau __NOTOC__ M&D Flugzeugbau is an aircraft manufacturing company based in Friedeburg Friedeburg is a municipality in the district of Wittmund, in Lower Saxony, Germany. It is situated approximately 14 km southeast of Wittmund, and 20 km ...

as the JS-MD Single, with a retractable MD-TJ42 turbojet engine mounted behind the cockpit.

Variants

;JS-1 :18 meter wingspan prototypes ;JS-1B :18 meter wingspan 18 metre class competition glider, production version. ;JS-1C :21 meter wingspan Open class competition glider

18 metre versions

21 metre version

EASA certification

Variants

Specifications (JS-1B)

See also

Notes

References

External links