Cat B procedures provide for minimum exposure to critical flight regimes during takeoff and landing. This also includes planning for a safe landing area in the mediate vicinity of the takeoff/landing spot should a loss of power be experienced. This procedure typically pertains to single engine machines but can be applicable to multi-engine aircraft that do not have the ability for continued flight after sustaining a loss of one engine. i.e. S-76A operating in Denver, CO
I guess that depends on the aircraft in question. The S61 RFM defines Cat B as the ability to attain a 10 ft wheel height. No mention what so ever about exposure during any phase of flight. I would hope we have come a bit further along since then but whenever I ask anyone at AW what is the definition of Cat B is they say " whatever is not Cat A"