Default P values outside range after Fw updating

I crashed my Mini Skyhunter running Revo with Arduplane V4.0.5 last week during hand launch takeoff in FBWA. It rolled to one side. I have successfully hand launch this plane over 5-6 times.Cannot download the DF log probably due to corrupt file.
Back to the bench, I did not immediately check the Servo Roll P value, but I found out the deflection of aileron is very small when hand-rolling the plane.

I then updated the FW to V4.1.6 . After updating, the Servo Roll P value (default) in Basic Tuning page is 0.05131736.

The param I keep on this plane before the crash shows the Servo Roll P value is 0.68 (FW V4.0.5) before updating to V4.1.6.

Have several questions :–

  1. Servo Roll P value of 0.05131736 and Pitch P value of 0.04 are both outside the range of 0.08~0.35. Is there a mistake in thes default values of the FW V4.1.6 ?
  2. Is there a significant change in the range of Servo Roll and Pitch PID over the last few major update ?
  3. I tried to enter a certain Servo Roll P value in MP V4.1.6. Sometimes MP automatically changes to a value inside the range, sometimes it does not change. I don’t know if I did something different in these 2 scenarios. If it does, that may partially explain why I got the odd figure of 0.05131736 which can come up only after autotune. And I did not do autotune on this plane before.
  4. Servo Roll + Pitch PID values were grouped under RLL2SRV and PTCH2SRV in the previous version of Fw (or MP). But in V.4.1.6 or even earlier, they are grouped under RLL and PTCH.What is the reason behind this re-grouping ? I cannot find the blog in DIYdrones on the release of the major update. Pls provide the link if available.

Hi @wcfung1

There was a major change in the PID control laws for fixed wing planes from AP4…x to AP4.1.x.
You should NOT try to apply the PID parameters for older versions to the newer ones. More details can found here: new PID’s

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Thank you for letting me know. The info put together by Tridge is very informative.