Since my views with respect to 'Exposure' have been referred to, it is probably best that they be accurately expressed. Rather than provide a lengthy monologue, anyone who is interested in them can read them in soon to be published RAeS Discussion Paper shown in draft here:
https://www.dropbox.com/s/vq36s43on3...ed%29.pdf?dl=0
The link to the RAeS paper will be provided when it is published.
Two other issues that need clarification are:
Contrary to what has been stated, an engine failure within the Category B profile
does require a landing within the serviceability limits of the helicopter in the take-off and landing profiles.
The scope of the H/V diagram was explained earlier in the thread in post 29 and was:
The Conditions of an H-V Diagram
The H-V Diagram defines an envelope of airspeed and height above the ground from which a safe power-off or OEI landing cannot be made. The flight manual should list any procedures which may apply to specific points (e.g. high speed points) and test conditions, such as runways surface etc.
The surface condition has relevance to the H-V Diagram only inasmuch as it represents a further limiting condition – i.e. a landing is not guaranteed in the case of an engine failure outside the H-V avoid curve if the surface conditions do not permit it. In ICAO, this additional factor is included in the definition of a safe-forced-landing – which consists of two elements:
the rate of closure with the surface following an engine failure; and,
the conditions of the surface on which a touchdown is made
Only the former is a condition of the H-V Diagram. Surface conditions are non-sequitur and have no place in the determination of compliance.
Jim