14 CFR §135.180

1. (a)Unless otherwise authorized by the Administrator, after December 31, 1995, no person may operate a turbine powered airplane that has a passenger seat configuration, excluding any pilot seat, of 10 to 30 seats unless it is equipped with an approved traffic alert and collision avoidance system. If a TCAS II system is installed, it must be capable of coordinating with TCAS units that meet TSO C-119.
2. (b)The airplane flight manual required by § 135.21 of this part shall contain the following information on the TCAS I system required by this section:
   1. (1)Appropriate procedures for—
      1. (i)The use of the equipment; and
      2. (ii)Proper flightcrew action with respect to the equipment operation.
   2. (2)An outline of all input sources that must be operating for the TCAS to function properly.