Reversible propellers have a discing/zero thrust pitch which is different for every model. Pilots use beta range to adjust their taxi speed. The RPM should begin from idle and increase up to a certain limit (95% for the PT6 engines).

What I see in MSFS is that initially my RPM decreases and then starts going up to the limit I set in the prop tables. As an example, for the Kodiak, we have the following reference values:

*Low idle RPM: 1080 +/-20*

**Prohibited Prop Operation RPM: 450-1050**

*Max reverse prop RPM: 2090*

What I'm getting in the sim:

*Low idle RPM: 1080 +/-20*

*Minimum RPM during beta cycle: 790*

**Max reverse prop RPM: 2090**

In the MSFS debug tools I observed that when the propeller beta is between beta_min and reverse, power absorbed and efficiency revert to a hardcoded 0.1 which leads to unrealistic RPM (and thrust). The propeller decreases speed and almost always enters underspeed mode. I am using legacy tables and even though I can explicitly set the Cp and n, both are completely ignored and the sim reverts to these default values.

__So it would be great if this hardcoded behaviour is removed in one of the next sim updates, which will allow us to flesh out our propellers and turboprops fully.__