Im flieger.shop finden jetzt einen aktuellen Flugzeugtest-Bericht über die eigenstartfähige Jonkers JS2 Revenant.
Why you should avoid too large winglets
The image shows a flow field around a wingtip without a #winglet. More precisely, it shows the extent of positive inflow angles at the tip region. The addition of a winglet would utilize this flow field and increase performance, only if it is inside the boundary of positive inflow angles. At higher flight speeds, the positive-inflow-angle flow field becomes smaller and areas of the winglet outside would have little benefit and creates additional drag. So that is why folks, you should avoid too large winglets! Source: Johan Bosman, chief engineer at Jonkers Sailplanes.
Maiden Flight of the JS2 Revenant
Jonker Sailplanes has completed the development of their most advanced glider designed to date – the JS2 Revenant. Uys Jonker, JS’s CEO, had the privilege to undertake the maiden test flight on 26 March 2021, while the marketing team broadcasted the event live across the globe. “This glider was designed to meet and exceed the expectations of all pilots looking for a self-launcher – great handling, great engine performance and easy to operate. Imagine a glider with modern Open Class performance, handling like an 18m glider and controls as light as a 15m glider – that is the JS2!”, Uys said. AP Kotze, JS 2 Revenant Project manager, added that the most important aspect during the development was the people behind the scenes. “I cannot have asked for a more engaged and committed R&D team – this made it possible to deliver a product as spectacular as the JS2 Revenant…”
According to Attie Jonker, Chief Design Engineer, the engineering attention to detail and elegant solutions to previously challenging areas make the JS2 extraordinary. “The main goals were to deliver a glider meeting the most demanding customer expectations in a self-launcher. A huge effort also went into ‘design for manufacturing’ and to improve the maintainability.”
The JS2 is arguably the most beautiful glider on the market – no other self-launch glider can boast with these slim and aerodynamically refined lines. “It was a challenge to design a fuselage with drag less than the proven JS1 while hosting a powerful 65hP fuel-injected engine.” Johan Bosman explained.
Within a week after the maiden flight, on the brink of the Easter long weekend, the JS2 did the first take off under its own power– adding some unexpected significance to the name Revenant. Watch the video here.