here is my higly respected Grund Instructors take on the selfsame issue:
CS25 111 and 115 specify the climb gradient requirements for certification.
These are still air gradients of climb. If they weren't then the gradient of climb would continually change with the prevailing wind. So its common sense that its a still air gradient!
The CLTOM graph is based upon still air. There is no wind input!
Clearly the wind effective gradient is different and it is this that gives the flight path angle.
Wind effective gradient = still air gradient x TAS/GS
We would use the wind effective gradient for obstacle clearance calculations.
this is matching my understanding and aided me in the EASA ATPL examinations for Performance,
however there STILL seem to be lot of confusion on this specific subject, even among line flying and military pilots
...
i find performance rather tricky, but take it as important bread and butter stuff, therfore my hunt for the truth... (its out there somewhere)
next step will be an email to Scully and Moulder
