Aeronautical Information Manual (AIM), page 74

Index   73 -- Page 74 -- 75

installed. TSO-C196() users and TSO-C129() GPS
users authorized for Class A1, A2, B1, B2, C1, or C2
operations may use GPS in place of another approved
means of long-range navigation, such as dual INS.
(See TBL 1-1-5 and TBL 1-1-6.) Aircraft with a
single installation GPS, meeting the above specifica-
tions, are authorized to operate on short oceanic
routes requiring one means of long-range navigation
(reference AC 20-138(), Appendix 1).
(b) Conduct GPS domestic, en route, and
terminal IFR operations only when approved
avionics systems are installed. Pilots may use GPS
via TSO-C129() authorized for Class A1, B1, B3,

C1, or C3 operations GPS via TSO-C196(); or

GPS/WAAS with either TSO-C145() or

TSO-C146(). When using TSO-C129() or

TSO-C196() receivers, the avionics necessary to

receive all of the ground-based facilities appropriate

for the route to the destination airport and any

required alternate airport must be installed and
operational. Ground-based facilities necessary for
these routes must be operational.

(1) GPS en route IFR operations may be
conducted in Alaska outside the operational service
volume of ground-based navigation aids when a
TSO-C145() or TSO-C146() GPS/wide area aug-
mentation system (WAAS) system is installed and
operating. WAAS is the U.S. version of a
satellite-based augmentation system (SBAS).
[a] In Alaska, aircraft may operate on
GNSS Q-routes with GPS (TSO-C129 () or
TSO-C196 ()) equipment while the aircraft remains

in Air Traffic Control (ATC) radar surveillance or

with GPS/WAAS (TSO-C145 () or TSO-C146 ())

which does not require ATC radar surveillance.

[b] In Alaska, aircraft may only operate
on GNSS T-routes with GPS/WAAS (TSO-C145 () or
TSO-C146 ()) equipment.

(2) Ground-based navigation equipment

is not required to be installed and operating for en

route IFR operations when using GPS/WAAS

navigation systems. All operators should ensure that

an alternate means of navigation is available in the

unlikely event the GPS/WAAS navigation system

becomes inoperative.

(3) Q-routes and T-routes outside Alaska.
Q-routes require system performance currently met

systems that satisfy the criteria discussed in AC
90-100(), U.S. Terminal and En Route Area
Navigation (RNAV) Operations. T-routes require
GPS or GPS/WAAS equipment.
AIM, Paragraph 5-3-4 , Airways and Route Systems
(c) GPS IFR approach/departure operations
can be conducted when approved avionics systems
are installed and the following requirements are met:
(1) The aircraft is TSO-C145() or TSO-
C146() or TSO-C196() or TSO-C129() in Class A1,
B1, B3, C1, or C3; and

(2) The approach/departure must be re-

trievable from the current airborne navigation

database in the navigation computer. The system

must be able to retrieve the procedure by name from

the aircraft navigation database. Manual entry of

waypoints using latitude/longitude or place/bearing

is not permitted for approach procedures.

(3) The authorization to fly instrument
approaches/departures with GPS is limited to U.S.

(4) The use of GPS in any other airspace
must be expressly authorized by the FAA Adminis-
(5) GPS instrument approach/departure
operations outside the U.S. must be authorized by
the appropriate sovereign authority.
4. Departures and Instrument Departure
Procedures (DPs)

The GPS receiver must be set to terminal (±1 NM)

CDI sensitivity and the navigation routes contained in

the database in order to fly published IFR charted

departures and DPs. Terminal RAIM should be
automatically provided by the receiver. (Terminal
RAIM for departure may not be available unless the
waypoints are part of the active flight plan rather than
proceeding direct to the first destination.) Certain

segments of a DP may require some manual

intervention by the pilot, especially when radar

vectored to a course or required to intercept a specific

course to a waypoint. The database may not contain

all of the transitions or departures from all runways

and some GPS receivers do not contain DPs in the

database. It is necessary that helicopter procedures be
flown at 70 knots or less since helicopter departure
procedures and missed approaches use a 20:1
obstacle clearance surface (OCS), which is double

1-1-20 Navigation Aids

Page 74 of the Aeronautical Information Manual (AIM.pdf)
AIM: Official Guide to Basic Flight Information and ATC Procedures

Index   73 -- Page 74 -- 75