AIM

4/3/14

1−2−7

Area Navigation (RNAV) and Required Navigation Performance (RNP)

d. Alternate Airport Considerations.

 For the

purposes of flight planning, any required alternate

airport must have an available instrument approach

procedure that does not require the use of GPS. This

restriction includes conducting a conventional

approach at the alternate airport using a substitute

means of navigation that is based upon the use of

GPS. For example, these restrictions would apply

when planning to use GPS equipment as a substitute

means of navigation for an out−of−service VOR that

supports an ILS missed approach procedure at an

alternate airport. In this case, some other approach

not reliant upon the use of GPS must be available.

This restriction does not apply to RNAV systems

using TSO−C145/−C146 WAAS equipment. For

further WAAS guidance see AIM 1−1−19.

1.

For flight planning purposes, TSO-C129()

and TSO-C196() equipped users (GPS users) whose

navigation systems have fault detection and

exclusion (FDE) capability, who perform a preflight

RAIM prediction at the airport where the RNAV

(GPS) approach will be flown, and have proper

knowledge and any required training and/or approval

to conduct a GPS-based IAP, may file based on a

GPS-based IAP at either the destination or the

alternate airport, but not at both locations.  At the

alternate airport, pilots may plan for applicable

alternate airport weather minimums using:

(a)

Lateral navigation (LNAV) or circling

minimum descent altitude (MDA);

(b)

LNAV/vertical navigation (LNAV/

VNAV) DA, if equipped with and using approved

barometric vertical navigation (baro-VNAV) equip-

ment;

(c)

RNP 0.3 DA on an RNAV (RNP) IAP, if

they are specifically authorized users using approved

baro-VNAV equipment and the pilot has verified

required navigation performance (RNP) availability

through an approved prediction program.

2.

If the above conditions cannot be met, any

required alternate airport must have an approved

instrument approach procedure other than GPS that is

anticipated to be operational and available at the

estimated time of arrival, and which the aircraft is

equipped to fly.

3.

This restriction does not apply to

TSO-C145() and TSO-C146() equipped users

(WAAS users). For further WAAS guidance see AIM

1−1−19.