I think the issue is what is being taught for exams. We understand that applying safety factors to the flight manual performance data is (for the most part) mandatory for commercial air transport but only advisory for private flights. The question is why the factors advised in the Skyway code are different from the factors required in CAT.POL.A. given the difference, which document are the PPL exams based on?
Specifically the safety factor applied to take off distance. CAT.POL.A.305 (performance class B) says
When no stopway or clearway available
(b) The unfactored take-off distance, specified in the AFM, shall not exceed:
when multiplied by a factor of 1,25, the take-off run available (TORA);
(This is also reflected in CAP 698 SEP1)
However the Skyway code states general safety factor for take off 1.33
In other respects the documents appear consistent with each other. In particular the factor for runway slope: CAT.POL.A says unless otherwise specified in the AFM, or other performance or operating manuals from the manufacturer, the take-off distance should be increased by 5% for each 1% of upslope. The skyway code recommends a factor of x 1.1 for each 2% of upslope on take off, which amounts to the same thing.
At an ATO it may be that your PART-ORA ATO manual requires the safety factors specified in CAT.POL.A (PART-NCO notwithstanding). In which case the 1.33 factor in the Skyway code (and PPL exams?) could be inconsistent with the ATO manual.
Last edited by Rivet gun; 15th Jun 2021 at 11:56.