Sec. 121.103 - En route navigational facilities.
(a) Except as provided in paragraph (b) of this section, each certificate holder conducting domestic or flag operations must show, for each proposed route, that nonvisual ground aids are --
(1) Available over the route for navigating aircraft within the degree of accuracy required for ATC; and
(2) Located to allow navigation to any regular, provisional, refueling, or alternate airport, within the degree of accuracy necessary for the operation involved.
Except for those aids required for routes to alternate airports, nonvisual ground aids required for approval of routes outside of controlled airspace are listed in the certificate holder's operations specifications.
(b) Nonvisual ground aids are not required for --
(1) Day VFR operations that the certificate holder shows can be conducted safely by pilotage because of the characteristics of the terrain;
(2) Night VFR operations on routes that the certificate holder shows have reliably lighted landmarks adequate for safe operation; and
(3) Operations on route segments where the use of celestial or other specialized means of navigation is approved by the Administrator.
[Doc. No. 6258, 29 FR 19194, Dec. 31, 1964, as amended by Amdt.
121-253, 61 FR 2610, Jan. 26, 1996]