There are four main types of prop pitch control:

- No control - prop with fixed pitch - like simple "one-piece" wooden propeller
- Propeller blades have spring counterweights that provide balance between aerodynamic forces on the blades and centripetal twisting moment on the blades and automatically set blades angle depending on aircraft speed.
- Manual pitch control - when you move the pitch handle (blue knob usually) you directly increase or decrease the angle of prop blades
- Commanded RPM control - when you move the pitch handle you "command" the RPM that prop should rotate. If the prop rotates faster or slower than the RPM commanded by the handle, then the prop will increase or decrease its blades pitch to adjust RPM with commanded.

Auto controlled:

Pilot controlled:

In X-Plane you can control prop pitch using these two DataRefs:

If your plane has Manual Pitch control:sim/cockpit2/engine/actuators/prop_angle_degrees - Pitch control, in degrees.

If your plane has a constant RPM speed control:sim/cockpit2/engine/actuators/prop_rotation_speed_rad_sec - Pitch RPM control, in radians per second (not RPM!).

What dataref to use depends on what airplane are you flying - with manual prop angle control or with commanded rotation speed control.

You can find this out in PlaneMaker - open you plane and see section - "Engine Specs -- > Location --> Prop". There you can see "manual pitch" or "constant RPM".

In the first case use the "prop_angle" dataref with a number for prop angle (say from 7 to 60 degrees) in config file (last number in these lines defines engine number):

A1 sim/cockpit2/engine/actuators/prop_angle_degrees 7,60 1In the second case use prop_rotation_speed_rad_sec dataref with a number for prop rotation speed (say from 70 to 280 rad/sec ):

A1 sim/cockpit2/engine/actuators/prop_rotation_speed_rad_sec 70,280 1the idle (say 600) and "red line" (say 2700).

Then, you need to convert Revolutions per minutes to Radians per second.

1 Rev (360deg) = 2*Pi radians.

So, your values will be:

idle = ( 600/60 ) * 2 * 3.14 = 62.8

max = ( 2700 / 60 ) * 2 * 3.14 = 282.6

A2 sim/cockpit2/engine/actuators/prop_rotation_speed_rad_sec 63,282

© Copyright 2012 - Vlad Sychev