I can’t seem to get the Bonanza to feather. If I simulate an engine failure it never stops spinning.
Propeller RPM does not change that much.
Is it something that did not get modeled into the Bonanza?
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The Bonanza doesn’t support the new propeller simulation yet. However I have modded mine in the past and it does “feather” if you add the prop options to the engine.cfg file etc. Currently I am not using the mod as updating to WU8/SU9 beta overwrote it.
Note: Feather may be the wrong term here, because I don’t know if the Bonanza supports changing pitch on the prop blades. That’s something I added myself when I made my mod (even though it might not have been technically correct for the plane).
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In real life, Bonanzas do not have feathering propellers. Come to think of it, I don’t know of any light piston single that DOES have a feathering prop. When you cut the engine in real life, the prop keeps turning due to the air flow over the prop, unless you slow down essentially to the stall speed.
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Are you talking about the
prop_feathering_available = 1 ; Prop feathering available? 0=FALSE, 1=TRUE
and
beta_feather = 89 ; Feathering pitch angle (degrees)
parameters?
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As stated, don’t believe the Bonanza feathers in real life.
The Baron does, and has the option in the virtual cockpit (and have my Bravo setup to utilize the feather option) however it is not modeled yet in the sim so does not actually work.
The FlySimWare Cessna 414 (Payware) does have functioning feathered props along with a few other payware aircraft.
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The one that I was riding in last Saturday did feather. That’s why I was trying to get the one in the sim going.
No. You should see in the engines.cfg file that the default value is feathering not supported.
prop_feathering_available = 0 ; Prop feathering available? 0=FALSE, 1=TRUE
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Feathering means manually changing pitch on the prop blades, which the Bonanza apparently doesn’t support. (Other people explain this more accurately than me below.)
I think you are really speaking about windmilling. The windmilling might be more accurate if you add support for the new prop simulation, but I won’t recommend it.
Example engines.cfg values from the Cessna Caravan:
[PROPELLER]
...
prop_mod_use_modern = 1
prop_mod_use_absorbed_torque = 1
prop_mod_aspect_ratio = 6
prop_mod_lift_slope_cf = 3.5
prop_mod_aoa_twist_delta_deg = 6.5
prop_mod_aoa_lift_delta_deg = 4
prop_mod_aoa_lift_delta_align_beta_deg = 25
prop_mod_stall_aoa_scaler = 2
prop_mod_stall_aoa_power = 2
prop_mod_stalled_cx = 1.0
prop_mod_beta_def_at_ratio = 0.75
prop_mod_lift_efficiency_cf = 0.2
prop_mod_zero_lift_drag_cf = 0.015
prop_mod_reverse_left = 0
prop_mod_reverse_right = 0
prop_mod_reverse_centre = 0
prop_mod_ang_offset_left = 0
prop_mod_ang_offset_right = 0
prop_mod_ang_offset_centre = 45
prop_mod_moment_scalar_pitch = 1
prop_mod_moment_scalar_yaw = 1
prop_mod_moment_scalar_roll = 1
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It actually had a feather position on the RPM lever (full back reading feather)? It certainly has an RPM lever but I don’t think it actually feathers?
Was it a G36 (as is in the sim) or was it an A36 with a turboprop conversion?
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The propeller governor on a Bonanza is powered by engine oil pressure. Without oil pressure the counterweights will hold the prop at full fine(max RPM) regardless of what you do with the propeller lever.
Edit: as per the post above mine, it may have been an aftermarket turbine mod, which would be out of scope for the default G36.
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So would this be correct?
Most propeller airplanes employ variable pitch propellers. A pilot can “feather” the propellers while on the ground to prepare for take-off without creating thrust. Once in the air, and as the pilot increases power, the angle of the blade adjusts to the RPM setting. At cruising altitude, the pitch of the propeller can be decreased while maintaining the desired RPM. Both features improve the aircraft’s performance and efficiency.
You also have fixed pitch as well (C152, C172 for example). Then you have variable pitch as well as constant speed propellers (which automatically change their pitch to the optimal setting).
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A variable pitch prop is similar to a gearbox/transmission in a car. When set to the climb position (full fine) it is like being in 1st gear. The engine (and prop) revs high but engine torque is maximized for the climb. When in level cruise flight, it is more efficient and quieter to choose a coarser pitch to lower the prop RPM.
If you don’t have a variable pitch prop, you have to choose between a climb prop or a cruise prop, or some compromise in between. Like the ‘fixed gear’ bicycles popular with hipsters 
Feathering usually refers to rotating the blades to an extremely coarse angle. This is usually only done to reduce drag in case of an engine failure, by stopping the propeller from ‘windmilling’.
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The Bonanza, as most high performance singles, has a constant speed propeller. This means you set the desired RPMs with the pitch lever and the governor tries to maintain the desired RPM by adjusting the pitch within a relatively limited range.
Unlike for instance turboprop propellers, the prop cannot:
- “disk”, i.e. go to essentially zero pitch where it presents the full face of the blade to the airflow and thus it only causes LOTS of drag and zero thrust while rotating
- nor can it feather, i.e. the blade cannot be set fully straight ahead so it presents essentially zero surface area to the airflow and therefore almost zero drag when stopped.
So yes: the Bonanza has a constant speed propeller with which you can adjust the engine RPM within a certain limited range. It does NOT have a feathering prop as the blades cannot rotate to a full fore-aft position.
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Thanks to all. I think I’ve got it now.
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Feathering means moving the blade angle close to 90 degrees in order to stop the propeller and reduce wind milling drag. The Bonanza has a constant speed propeller but it does not have a reverse or feathering range.
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For the OP, it’s all explained here:
And here:
Point of feathering is to reduce drag to a possible minimum to get the best possible performance in a twin engine airplane to reach a save destination in case of an engine failure. There is absolutely no point in feathering a single engine airplane like a Bonanza as the only way in case of an engine failure is “down” anyway. The typically only single engine planes with a combustion engine that can feather their props are motor gliders like for example a Falke or a Dimona. Here the feathering comes from the intention of stopping the engine in flight.
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I just wanted to glide with the prop feathered because it looks cool 
You should be able to on the TBM