PROP FEATHERING INHIBIT and Disabled propeller controls

My engine setup has the Propeller lever disabled through the engines.cfg file, as the real plane doesn’t have a propeller lever. This makes (A:PROP FEATHERING INHIBIT:1, Bool) to be always true, so there is no way to feather the propeller using the (K:TOGGLE_FEATHER_SWITCH_1) or (K:AXIS_PROPELLER1_Set).

In order to achieve this, I’m using the forced beta which sets the prop to the right pitch, but then I am having an issue where the propeller will spin in reverse (see here).


  1. Is there a way to trigger propeller feather when the prop lever is disabled?
  2. If no, can you make it possible in the next flight model update? The PC-12 is one example of an aircraft where the propeller is feathered using the condition lever and there is no propeller lever. Other planes are the TBM930 with that weird power lever, or the M500.

Hello @SWSAlexVletsas

As far as I can tell, there is no way to manually feather the propeller when the prop lever is disabled as the events to set the propeller angle will be ignored (I think auto feathering will still work though).

Have you considered leaving the prop lever enabled and forcing its position value to 0 or 1 depending on your condition lever position?
Or you have a good reason to want to avoid this?


I prefer to avoid this. While I can set the propeller lever to whatever I need it to be in an section, if the user has a desktop controller with a propeller lever, as soon as he moves the lever the propeller will change momentarily and then the will catch it and correct it. While it is workable it is not smooth.

Furthermore, this jerking of the propeller lever can result in exceeding engine torque limits and damage the engine, which is a thing now with payware turboprop modules, including ours.

The actual aircraft mentioned above (PC-12, M500, TBM) do not have a propeller lever in reality. To feather them you set the condition lever to cutoff and their engine is either feathered or runs at 100% prop RPM.

I was able to work around the problem using the Forced Beta system. However, I need to ask you @FlyingRaccoon if there is a special “feathered” state in the flight model, or if it is the same as setting the prop beta to the appropriate angle via forced beta. If it is the same, problem solved. If, however, there are other things running when the prop is feathered via the lever VS forced beta, then we need a solution to feather it even without the lever.

Fair enough.

Most of the feathering logic is used in the case of auto feathering.
Writing the beta angle directly is fine. Some of the configuration like min_rpm_for_feather and beta_feather will be bypassed but that’s about it.

You mentioned the propeller spins in reverse and produces negative thrust when setting the expected beta angle?
Does this happen in specific conditions? I tried reproducing the issue with the Marketplace version of your PC-12 without success.


There is no thrust produced (legacy tables/efficiency is set to zero) but the propeller spins at -1 to -2 RPM while gliding. Go for 100-120kts which is the best glide speed range.

I fiddled with the power absorbed to reduce or negate the effect but it wouldn’t stop it. The only thing that got it under control was increasing the moment of inertia to more than 2x the real value, which caused the propeller to almost stop but then the startup timings were completely wrong.

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