Heli Performance standards
Could someone either simply explain (or provide a link to where I can read about) the different categories of performance that apply to public transport operations in the UK. I have heard, but don't understand, the expression Performance A, for example. What is the correct terminology for the different levels of standards from PPL(H) Private to fully Twin IFR offshore. Clearly paying money to hire a helicopter from a CAA approved carrier means higher standards will apply on various criteria.
Thanks