Derivatives 21 Part 0
In the lower half of the in-editor FAR Analysis page labelled "Data + Stability Derivatives" we find 21 static stability derivatives. All of the static stability derivatives tell us about the airplane's initial reaction to a disturbance encountered during steady cruise flight.
The 21 static stability derivatives are divided in to seven columns with three published derivatives in each column. Three columns show the reaction to a velocity disturbance (forward, downward or sideward; purple frame). Three columns show the effects of in-flight airplane rotation (pitch up, roll right or yaw right; blue frame). The last column shows the response to increased yoke back pressure (pitch up control surface deflection; brownish frame).
We will discuss each category of derivative on its own page:
Downward velocity disturbance derivatives in -- TODO -- part 1(a)
Forward velocity disturbance derivatives in -- TODO -- part 1(b)
Sideways movement disturbance derivatives in -- TODO -- part 1(c)
Rotation effect derivatives in -- TODO -- part 2
Pitch responsiveness derivatives in -- TODO -- part 3
The static stability derivatives are also used to explore the dynamic stability of the airplane. It can be done from the 'Stability Deriv Simulation' page in the SPH or VAB, and it can be done from outside KSP as well. On -- TODO -- this page (Dynamic Stability Estimates) we see how to easily use exported static stability derivatives to explore cruise flight dynamic stability in Octave.