In certification, the provision of Category A and/or Category B procedures/profiles is required. The manufacturer provides these, meeting the specific conditions set out in the requirements (hopefully, utilising the guidance). They ensure that, following a power-unit failure, a safe landing (to the conditions required) can be achieved by an average pilot:
- The Category B procedure/profiles ensures that flight is conducted outside of the HV Diagram (the surface over which the take-off/landing is conducted is defined);
- Category A procedures/profiles are flight tested to ensure that they can be constrained within a safe flight envelope (i.e. the HV Diagram is not applicable).
The question of whether these procedures/profiles are mandated is moot; for Category A, it really depends on the contents and intent of the definition of 'Category A' applied in the State of Operation. In European regulations, they are not mandated.
In ICAO Standards and EASA regulations,
only the objective criteria is specified, the procedure/profile to be flown is not. Provided the criteria can be met,
any profile is available to the pilot. If there are constraints, they are to be found within the instructions issued by the organisation that has Operational Control.
Procedures contained in the non-approved section of the Flight Manual do not have to have Approval by the Certificating Authority; they are offered as best practice for acceptance by the Operational Oversight Authority.
For those with more than a passing interest in the Category A/Category B certification discussion (described above, for the AW139, by Dino Baggi), Appendix B of the following document contains a dissertation on "Appropriate Standards for Passenger Carriage".
https://www.dropbox.com/s/uh634o35dh...A-CHC.pdf?dl=0
https://onedrive.live.com/redir?resi...int=file%2cpdf
Other parts of the document describe elements that are germane, mostly, to the application of the HV diagram - although they do chart the history of the amendments to Part 29.1 (and associated rules) with respect to Passenger Carriage/Utility Operations (aerial work)
and the nexus between certification and operations.
Jim