125.203 Communication and navigation equipment.§ 125.203 Communication and navigation equipment.
(a) Communication equipment - general. No person may operate an airplane unless it has two-way radio communication equipment able, at least in flight, to transmit to, and receive from, appropriate facilities 22 nautical miles away.
(b) Navigation equipment for operations over the top. No person may operate an airplane over the top unless it has navigation equipment suitable for the route to be flown.
(c) Communication and navigation equipment for IFR or extended over-water operations - General. Except as provided in paragraph (f) of this section, no person may operate an airplane carrying passengers under IFR or in extended over-water operations unless -
(1) The en route navigation aids necessary for navigating the airplane along the route (e.g., ATS routes, arrival and departure routes, and instrument approach procedures, including missed approach procedures if a missed approach routing is specified in the procedure) are available and suitable for use by the aircraft navigation systems required by this section;
(2) The airplane used in those operations is equipped with at least the following equipment -
(i) Except as provided in paragraph (d) of this section, two approved independent navigation systems suitable for navigating the airplane along the route within the degree of accuracy required for ATC;
(ii) One marker beacon receiver providing visual and aural signals;
(iii) One ILS receiver;
(iv) Two transmitters;
(v) Two microphones;
(vi) Two headsets or one headset and one speaker; and
(vii) Two independent communication systems, one of which must have two-way voice communication capability, capable of transmitting to, and receiving from, at least one appropriate facility from any place on the route to be flown; and
(3) Any RNAV system used to meet the navigation equipment requirements of this section is authorized in the certificate holder's operations specifications.
(d) Use of a single independent navigation system for operations under IFR - not for extended overwater operations. Notwithstanding the requirements of paragraph (c)(2)(i) of this section, the airplane may be equipped with a single independent navigation system suitable for navigating the airplane along the route to be flown within the degree of accuracy required for ATC if -
(1) It can be shown that the airplane is equipped with at least one other independent navigation system suitable, in the event of loss of the navigation capability of the single independent navigation system permitted by this paragraph at any point along the route, for proceeding safely to a suitable airport and completing an instrument approach; and
(2) The airplane has sufficient fuel so that the flight may proceed safely to a suitable airport by use of the remaining navigation system, and complete an instrument approach and land.
(e) Use of VOR navigation equipment. If VOR navigation equipment is required by paragraph (c) or (d) of this section, no person may operate an airplane unless it is equipped with at least one approved DME or a suitable RNAV system.
(f) Extended over-water operations. Notwithstanding the requirements of paragraph (c) of this section, installation and use of a single long-range navigation system and a single long-range communication system for extended over-water operations in certain geographic areas may be authorized by the Administrator and approved in the certificate holder's operations specifications. The following are among the operational factors the Administrator may consider in granting an authorization:
(1) The ability of the flight crew to navigate the airplane along the route to be flown within the degree of accuracy required for ATC;
(2) The length of the route being flown; and
(3) The duration of the very high frequency communications gap.[Doc. No. FAA-2002-14002, 72 FR 31682, June 7, 2007]