JS1-C Accident - 20 January 2014


Jonker Sailplanes sends its heartfelt condolences to the family and friends of the pilot involved in the fatal accident at Bloemfontein on Monday 20th January involving JS1C-21 s/n 056. This is a terrible and sad loss of a gliding friend and member of the JS family.

Jonker Sailplanes is supporting and assisting the South African CAA with its accident investigation. Initial investigations have found no technical defect that could have caused the accident.

The CAA accident investigation is ongoing and Jonker Sailplanes will communicate any relevant details to owners, operators and customers when the CAA investigation is complete.

Some days in Africa are just amazing - 5 November 2013


The longest glider flights ever from Potchefstroom has been recorded on Tuesday 5 November 2013! John Coutts, flying a JS1-A, Uys Jonker in his JS1-B and Oscar Goudriaan in his 21m JS1-C set of on a declared 1000km task. Oscar explains the day on SoaringCafe ( as follows:

Potch-Harrismith-Lesotho-Potch flight 750km - 2 November 2013


Great flying day! Uys and John Coutts did the Potch-Harrismith - Lesotho-Potch flight (750km)

First two 1000km flights for the season in South Africa completed


The first two 1000km flights for the season in South Africa were successfully completed today  11 October 2013 by Oscar Goudriaan and Pieter Nouwens.

North West Regional Gliding Championships - 21 September 2013


Potchefstroom Akavlieg Gliding Club hosted the 2013 North West Regionals Gliding Championships, that finished today. Thirty three pilots participated in three classes, Open, 15m and Club Class.

Test flight of the 52th JS1 - 6 September 2013


The test flight of the the 52th JS1 - the Certificate of Airworthiness was just issued today by the SACAA, just in time for the handover this weekend!


Russell Cheetham wins the UK 18 Metre Nationals in his JS1-C


Congratulations to Russell Cheetham on winning the UK 18 Metre Class Nationals, Bicester 17- 25th August 2013.

Flying his JS1-C, Russell flew steadily and consistently to take first place in a highly competitive and closely fought competition featuring many current and former British Team pilots and international medal winners.

JS1 winning the Polish Nationals


JS1 winning the Polish Nationals!

Last competition day of the Polish Nationals showed much better weather. The task was big and all the time of the day was needed to fly the 528km.

Karol Staryszak won the day, but Łukasz Wójcik flying the JS1 won the competition!
Very well done Łukasz and congratulations from Jonker Sailplanes!

21 metre JS1-C takes top three places in 2013 UK Open Class Nationals


Three 21 metre JS1-C Revelations flown by British Team pilot Russell Cheetham, former Standard Class World Champion Andy Davis and Iain Evans competed in the Open Class at the combined UK Open and Standard Class Nationals held at Aston Down from 3rd to 11th August 2013


Roll out of the 50th JS1 Revelation: 3 August 2013


Jonker Sailplanes celebrated a significant milestone when the 50th JS1-Revelation was rolled out of the Potchefstroom factory on 2 August. At the same time the company’s new manufacturing facilities were officially opened, and the SACAA Type Certificate for the JS1-C 18/21 was formally handed over following approval granted in March this year.


TJ-42 Certification update - 22 July 2013


JS had a technical workshop with M&D in July 2013 in Friedeburg, Germany.

Good progress has been made with the Type Certification of the TJ-42 Jet Turbine.

The focus in the past months has been on the most time-consuming tests, including the 50h endurance test and the vibration test.

Type Certification for the JS1 Revelation 21m -  27 May 2013


The Type Certificate for the JS1-21m has now been fully approved by the South African Civil Aviation Authority (SACAA)! Type Certificate Data Sheet (TCDS) were received on May 27th 2013 after 18 months of dedicated work by Jonker Sailplanes’ and SACAA engineers.

Jonker Sailplanes started the JS1-21m project 12 months prior to the 31st FAI World Gliding Championships in Uvalde (2012). The biggest challenge was to avoid interrupting the production of the certified JS1-18 sailplane during the development and certification phase of the new 21m wingspan variant.

African and Polish record for 500km triangular course -  14 March 2013

During the 2013 Helli Lasch Challenge at the Tswalu Game Reserve in the Kalahari the JS1 claimed two 500km speed records.

Sebastian Kawa, the current 15m and Standard Class World Champion completed the 500km triangular course at 168km/h, setting a new Polish Record in the Open Class.

Uys Jonker, flying the same task, set a new African record with a speed of 169.8km/h.

JS1-TJ Certification updates - 5 March 2013

  Official JS1-TJ flight trails started in March 2013. For the first flight, the flight test engineer team lead by Richard Starke planned a “serious flight test”, according to Uys Jonker. With the possible use of the engine a number of tests could be completed with a single take off. This included:

Lukasz Wojcik
2013 Polish Nationals, Open Class, 1st
Uys Jonker
2012 World GC (Uvalde),18m class, 6th
2010 World GC, 18m class, 2nd
2009 SA Nationals, Open Class, 1st
2013 NW Regionals, Open Class, 1st
Attie Jonker
2010 World GC, 18m class, 5th
2008 SA Nationals, Open Class, 1st
2007 SA Nationals, Open Class, 1st
2006 SA Nationals, Open Class, 1st
2013 NW Regionals, Open Class, 2nd
Russel Cheetham
2013 UK Nationals, 18m class, 1st
2013 UK Nationals, Open class, 2nd
2012 Hahnweide (Germany), 18m class, 1st
2012 UK Nationals, 18m class, 2nd
2012 World GC (Uvalde), 18m class, 4th
2011 European GC (Lithuania), 18m class, 3rd
Andy Davis
2013 UK Nationals, Open Class, 1st
2012 African Grand Prix Potchefstroom, 1st
2010 British Nationals, Open Class , 1st
2010 UK Nationals, 18m class, 2nd
2009 British Nationals, 18m class, 1st
Oscar Goudriaan
2013 SA Nationals, Open Class, 1st
2012 World GC (Uvalde), Open Class, 3rd
2011 SA Nationals, Open Class, 1st
2010 SA Nationals, Open Class, 1st
Christophe COUSSEAU
2013 European GC,  18m class, 2nd
Killian Walbrou
2013 European GC, Open Class, 2nd
Bruce Taylor
2012 World GC (Uvalde), Open Class, 6th
2011 Australian Grand Prix, 1st
Ronald Termaat
2013 European GC, Open Class
2012 Dutch Nationals, Open Class , 1st
2012 World GC (Uvalde), 18m class , 7th
2011Dutch Open Class Nationals, 1st
Bill Elliot
2008 USA Nationals, 18m class, 1st
Brett Hunter
2012 NZ Nationals, Open Class, 1st
Anders Anderson - Danish Records
Out and return distance 912,3 km
Free out and return distance 918,6 km
Speed 100K triangle 164,62 kph
Speed 300K triangle 151,6 kph
Speed 300K out and return 175,9 kph
Speed 500K out and return 175,9 kph
November 2012 - SA Grand Prix
Andy Davis :1st place
Oscar Goudriaan : 2nd place
Laurens Goudriaan: 3rd place
August 2012 Oscar Goudriaan finished 3rd in the Open Class in the JS1-C 21m.



+27(0)18 285 1035
Hangar 22 & 23, Potchefstroom Airfield
1 Tiger Moth Street
South Africa
+27(0)18 293 1335
Jonker Sailplanes
P Bag X1293
South Africa


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