June 2017 marked an incredible milestone for the JS-MD Partnership when the JS1 variant, the JS-MD 1C, was awarded type certification from EASA. Now two years later on the 18th of July the next huge milestone was achieved with the EASA approval of the JS-MD 3.
The amount of resources and effort that goes into achieving this approval is just enormous. As Uys commented on Facebook “Designing a sailplane with the ultimate performance requires you to touch various edges of the certification envelope. Showing compliance when designing on the edge always takes longer as test data must sometimes be verified with the additional observed tests.”
In the following video an excited Uys Jonker (CEO Jonker Sailplanes) and Keno Markwald (COO M&D Flugzeugbau GmbH) talks about the issued JS3 TYPE CERTIFICATE.
Most of the demonstration tests were already completed in 2017. Probably the most interesting part of certification, and sometimes the most scariest, is the flight testing. Flight tests were done by Uys Jonker and AP Kotze and certain verification flight tests done by Soeren Pederson, our EASA Class 1 test pilot.
Flight tests consist of performance test (like stall speeds, roll rates and descent rates), handling characteristics (longitudinal stability, winch/aerotow behaviour, control force loads) and then of course the high risk tests, where the pilot normally double checks his parachute before take-off. These critical tests included the spin test, high speed test and high speed airbrake deployment tests.
To see some of these tests in action, straight from the cockpit, watch the following video:
On 28 September 2017 the structural test of the JS3 wing was also successfully completed. The wing was able to meet the minimum requirement with ease and a considerable load carrying reserve was proven by testing to destruction. Failure occurred at a load 20% higher than the requirement.
After all the demonstration tests were completed the process to verify the documentation started.
JS/M&D really went the extra mile to construct pilot manuals that are at a next level. Especially with the Maintenance Manual great effort and time was put in to provide the customer with a user friendly, detailed and comprehensive document.