AIM

8/15/19

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2

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8

Performance

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Based Navigation (PBN) and Area Navigation (RNAV)

2.

Use of a suitable RNAV system as an

Alternate Means of Navigation when  a VOR, DME,
VORTAC, VOR/DME, TACAN, NDB, or compass
locator facility including locator outer marker and
locator middle marker is operational and the
respective aircraft is equipped with operational
navigation equipment that is compatible with
conventional navaids. For example, if equipped with
a suitable RNAV system, a pilot may fly a procedure
or route based on operational VOR using that RNAV
system without monitoring the VOR.

NOTE

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1.

Additional information and associated requirements

are available in Advisory Circular 90-108 titled “Use of
Suitable RNAV Systems on Conventional Routes and
Procedures.”

2.

Good planning and knowledge of your RNAV system are

critical for safe and successful operations.

3.

Pilots planning to use their RNAV system as a substitute

means of navigation guidance in lieu of an out

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of

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service

NAVAID

 may need to advise ATC of this intent and

capability.

4.

The navigation database should be current for the

duration of the flight. If the AIRAC cycle will change
during flight, operators and pilots should establish
procedures to ensure the accuracy of navigation data,
including suitability of navigation facilities used to define
the routes and procedures for flight.  To facilitate validating
database currency, the FAA has developed procedures for
publishing the amendment date that instrument approach
procedures were last revised. The amendment date follows
the amendment number, e.g., Amdt 4 14Jan10. Currency of
graphic departure procedures and STARs may be
ascertained by the numerical designation in the procedure
title. If an amended chart is published for the procedure, or
the procedure amendment date shown on the chart is on or
after the expiration date of the database, the operator must
not use the database to conduct the operation.

b. Types of RNAV Systems that Qualify as a

Suitable RNAV System. 

When installed in accor-

dance with appropriate airworthiness installation
requirements and operated in accordance with
applicable operational guidance (for example,
aircraft flight manual and Advisory Circular
material), the following systems qualify as a suitable
RNAV system:

1.

An RNAV system with TSO

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C129/

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C145/

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C146 equipment, installed in accordance

with AC 20

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138, Airworthiness Approval of Global

Positioning System (GPS) Navigation Equipment for

Use as a VFR and IFR Supplemental Navigation
System, and authorized for instrument flight rules
(IFR) en route and terminal operations (including
those systems previously qualified for “GPS in lieu of
ADF or DME” operations), or

2.

An RNAV system with DME/DME/IRU

inputs that is compliant with the equipment
provisions of AC 90

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100A, U.S. Terminal and

En Route Area Navigation (RNAV) Operations, for
RNAV routes. A table of compliant equipment is
available at the following website:

https://www.faa.gov/about/office_org/headquart
ers_offices/avs/offices/afx/afs/afs400/afs410/medi
a/AC90

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100compliance.pdf

NOTE

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Approved RNAV systems using DME/DME/IRU, without
GPS/WAAS position input, may only be used as a substitute
means of navigation when specifically authorized by a
Notice to Airmen (NOTAM) or other FAA guidance for a
specific procedure. The NOTAM or other FAA guidance
authorizing the use of DME/DME/IRU systems will also
identify any required DME facilities based on an FAA
assessment of the DME navigation infrastructure.

c. Uses of Suitable RNAV Systems.

Subject to

the operating requirements, operators may use a
suitable RNAV system in the following ways.

1.

Determine aircraft position relative to, or

distance from a VOR (see NOTE 6 below), TACAN,
NDB, compass locator, DME fix; or a named fix
defined by a VOR radial, TACAN course, NDB
bearing, or compass locator bearing intersecting a
VOR or localizer course.

2.

Navigate to or from a VOR, TACAN, NDB,

or compass locator.

3.

Hold over a VOR, TACAN, NDB, compass

locator, or DME fix.

4.

Fly an arc based upon DME.

NOTE

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1.

The allowances described in this section apply even

when a facility is identified as required on a procedure (for
example, “Note ADF required”).

2.

These operations do not include lateral navigation on

localizer

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based courses (including localizer back

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course

guidance) without reference to raw localizer data.

3.

Unless otherwise specified, a suitable RNAV system

cannot be used for 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