No person may operate an aircraft unless it is equipped with -
(a) A sensitive altimeter that is adjustable for barometric pressure;
(b) Heating or deicing equipment for each carburetor or, for a pressure carburetor, an alternate air source;
(c) For turbojet airplanes, in addition to two gyroscopic bank-and-pitch indicators (artificial horizons) for use at the pilot stations, a third indicator that is installed in accordance with the instrument requirements prescribed in § 121.305(j) of this chapter.
(d) [Reserved]
(e) For turbine powered aircraft, any other equipment as the Administrator may require.
[Doc. No. 16097, 43 FR 46783, Oct. 10, 1978, as amended at Amdt. 135-1, 44 FR 26737, May 7, 1979; Amdt. 135-34, 54 FR 43926, Oct. 27, 1989; Amdt. 135-38, 55 FR 43310, Oct. 26, 1990]