Category B,
Category B, with respect to transport category rotorcraft, means single-engine or multiengine rotorcraft which do not fully meet all Category A standards. Category B rotorcraft have no guaranteed stay-up ability in the event of engine failure and unscheduled landing is assumed.
Source
14 CFR § 1.1
Scoping language
As used in Subchapters A through K of this chapter, unless the context requires otherwise: