Use of Suitable Area Navigation (RNAV) Systems on Conventional Routes and Procedures.
For complete details refer to: Advisory Circular 90-10 Date: 3/3/11 This circular provides guidance regarding the suitability and use of RNAV systems while operating on, or transitioning to, conventional, i.e., non-RNAV, routes and procedures within the United States (U.S.) National Airspace System (NAS)1. Use of a suitable RNAV system as a substitute means of navigation when a: VOR, DME, TACAN, VORTAC, VOR/DME, NDB, LOC), — is out of service — the NAVAID information is not available — an aircraft is not equipped with an ADF or DME — or the installed ADF or DME is not operational. EXAMPLE: If equiped with a suitable RNAV system, a pilot may hold over an out-of-service NDB. 2. Use of a suitable RNAV system as an Alternate Means of Navigation when a (VOR, DME, TACAN, VORTAC, VOR/DME, NDB, LOC), — is operational — the aircraft is equipped with operational navigation equipment that is compatible with conventional NAVAIDs. EXAMPLE: If equipped with a suitable RNAV system, a pilot may fly a procedure or route based on operational VOR using the RNAV system without monitoring the VOR. 3. Suitable RNAV system are installed in accordance with appropriate airworthiness installation requirements: — TSO-C129/-C145/-C146 equipment … authorized for IFR en route and terminal operations (including those systems previously qualified for “GPS in lieu of ADF or DME” operations. 4. Usage of Suitable RNAV systems: — Determine aircraft position relative to or distance from a VOR, TACAN, NDB, compass locator, DME fix, or named fix defined by a VOR radial, TACAN course, NDB bearing, or compass locator bearing intersecting a VOR or Localizer (LOC) course. –Navigate to/from a VOR, TACAN, NDB, or compass locator. –Hold over a VOR, TACAN, NDB, compass locator, or DME fix. –Fly an arc based upon DME. 5. Usage of Suitable RNAV systems NOT ALLOWED: — Unless otherwise specified, navigation on procedures that are identified as not authorized (“NA”) without exception by a NOTAM. For example, an operator may not use a RNAV system to navigate on a procedure affected by an expired or unsatisfactory flight inspection, or a procedure that is based upon a recently decommissioned NAVAID.