... silly me ....
I always thought that the necessaries would be in the AFM/POH and the FMS for the particular bit of kit.
Amplification I thought one might find in the OEM's operator guidance paperwork for the bit of kit ....
Guess I haven't learned much at all over the years ...
.. but I do know what I prefer to hold up in my little hand in court when the barristers are trying to hang my hide on the wall out back of the shed ....
Regulator approved certification documents and authoritative OEM words win out every time against OWTs.
A sound and thorough endorsement engineering workup is far better than two quick circuits .. and I have done both in the past .. having to catch up on the deficiencies myself in the case of the latter ..