AirStar Hughes 500e with JetCat PHT3 - problem with rotor speed sagging.
I was flying my big Hughes this morning and suffered what I thought was a power loss. After landing safely I realised that the rotor speed was simply not as high as it should be. The turbine was still running within and upto all the limits, so it was just the rotor not getting up to speed. After a close look I found the clutch bell was slipping on the pinion gear shaft (this is the pinion and shaft that runs on the main gear). I tightened this and was confident that the problem had been solved. Alas, it did not - so whilst the clutch bell may have been slipping, it was not the main cause.
I have checked the one way bearings on the main gear/main shaft - all is good. All the pully's with the tooth belts are running freely without any friction. I have not taken the clutch assembly apart and is hoping that I don't have to.
Anyone with any ideas?