The endurance ground test program has been finished. It was part of German certification in order to get the permit to fly (PTF). In sum more than 30 hours were performed in different environmental conditions. The rotor system and also the control system were loaded permanently to identify weak or unreliable design properties.
In additon to that, the engine also carried out reliability and full-load tests succesfully.
It was also proved that the cooling system works very efficiently, at least in tested temperatures until 20°C. More tests will be carried out in hotter conditions. But with measured data we could witness that there is a lot of reserve for hotter temperatures.
The endurance tests are a big step towards the PTF, which will allow us to start flight testing.