912 iS Sport - cyclically vary RPM

Re: 912 iS Sport - cyclically vary RPM

by Glenn Martin » 7 years ago

Glenn Martin

4 291 858

Hi Uladzimar,
the TL-Ultralight constant speed controller box is partially faulty. Ask TL for a new one. Alternatively if you know someone else with a Sirrus or Sting swap one around.

It is normal for the controller to cycle and settle as the PID copes with changes in rpm but this graph shows the PID id not working. I believe even in manual mode the constant speed box does a pseudo straight through control and in eithe mode this data indicates the box is faulty.

Glenn

Re: 912 iS Sport - cyclically vary RPM

by Uladzimir » 7 years ago

Uladzimir

1 8 0

Hi Glen
Thanks for the answer.
I have a hydraulic propeller pitch change system. It does not have a constant speed controller. Only manual control from the cab.

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Re: 912 iS Sport - cyclically vary RPM

by Glenn Martin » 7 years ago

Glenn Martin

4 291 858

Hi,
thanks a very different controller to the sirrius I have seen ! What does TL say about your problem ?

Re: 912 iS Sport - cyclically vary RPM

by Uladzimir » 7 years ago

Uladzimir

1 8 0

A TL representative wrote to me that I should contact Rotax.
Rotax wrote to me that my request was forwarded to the Moscow representative.
They have not answered yet.
Maybe this is somehow related to the fact that the engine running time by ECU is 267 hours. The operating time by Garmin is 162 hours. TL say that this is due to a different approach to the calculation of time.
I hardly believe in such stories.
Probably, need to do 200 hour maintenance.
Replace the spark plugs.