(a) No person may operate an airplane unless at least the following
number of flight attendants are on board the airplane:
(1) For airplanes having more than 19 but less than 51 passengers on
board, one flight attendant.
(2) For airplanes having more than 50 but less than 101 passengers on
board, two flight attendants.
(3) For airplanes having more than 100 passengers on board, two flight
attendants plus one additional flight attendant for each unit (or part of
a unit) of 50 passengers above 100.
(b) No person may serve as a flight attendant on an airplane when
required by paragraph (a) of this section unless that person has
demonstrated to the pilot in command familiarity with the necessary
functions to be performed in an emergency or a situation requiring
emergency evacuation and is capable of using the emergency equipment
installed on that airplane.