The RFM will provdie the accepted manufacturer data to determine these numbers. The cruise chart for the appropriate DA would a good place to start. This chart will show the Vy, and resulting power required, for the DA and aircraft GWT and the maximum power available. Should the maximum power available not be on the chart then this figure will also be published in the RFM.
A civil RFM ain't got any of that.
Originally Posted by
Ascend Charlie
"Practicable" (this is the word used mostly, not "practical") is when you are confident that with one engine only, you can make it to a safe chosen place to run it on.
Bell uses practical.