Loading Procedures from Databases

Most IFR pilots who use GNSS (GPS) are aware that they must load instrument approach procedures (IAPs) by name from the unit’s database. But there’s some confusion in IFR land about flying instrument departure procedures, arrivals, and other routes.

For more information about database currency, see Database Currency for IFR Operations here at BruceAir.

AIM 1−1−17. Global Positioning System (GPS), 2. IFR Use of GPS, includes the following paragraph about IAPs:

(3) All approach procedures to be flown must be retrievable from the current airborne navigation database supplied by the equipment manufacturer or other FAA−approved source. The system must be able to retrieve the procedure by name from the aircraft navigation database, not just as a manually entered series of waypoints. Manual entry of waypoints using latitude/longitude or place/bearing is not permitted for approach procedures. (p. 1−1−20)

That language specifically address IAPs, but it doesn’t mention DPs, STARs, or airways.

If you use an IFR-approved GNSS (see AIM 1−1−17. Global Positioning System (GPS), 2. IFR Use of GPS for the details), you should check the Aircraft Flight Manual Supplement or the AFM (if you fly an aircraft with an IFR-approved GNSS installed as original equipment) for the limitations associated with the unit(s) in your aircraft.

For example, the AFM supplement (a required document for a unit installed under an STC) for the Garmin GNS 530W includes the following language:

2.5 Flight Planning

Whenever possible, RNP and RNAV routes including Standard Instrument Departures (SIDs), and Standard Terminal Arrival (STAR), routes should be loaded into the flight plan from the database in their entirety, rather than loading route waypoints from the database into the flight plan individually. Selecting and inserting individual named fixes from the database is permitted, provided all fixes along the published route to be flown are inserted. Manual entry of waypoints using latitude/longitude or place/bearing is prohibited. (Garmin document 190-00357-03_F)

Similar language appears in the AFM supplements for the GNS 430, GTN 750, and GTN 650 units. For example:

2.4 Flight Planning

Whenever possible, RNP and RNAV routes including Standard Instrument Departures (SIDs), Standard Terminal Arrival (STAR), and enroute RNAV “Q” and RNAV “T” routes should be loaded into the flight plan from the database in their entirety, rather than loading route waypoints from the database into the flight plan individually. Selecting and inserting individual named fixes from the database is permitted, provided all fixes along the published route to be flown are inserted. Manual entry of waypoints using latitude/longitude or place/bearing is prohibited. (AFMS, Garmin GTN GPS/SBAS System, 190-01007-A2 Rev. 8)

You should take care, however, when entering a departure procedure as a series of fixes rather than by name from the database. A DP is more than a series of points defined by LAT/LON. A DP typically contains several types of legs, and you must ensure that you understand how each leg works and how the GNSS in your aircraft handles different leg types and interfaces with your autopilot.

You can find more information about leg types in Avoiding Confusion when Flying GPS Legs here at BruceAir. See also Chapter 6 of the Instrument Procedures Handbook.

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.

%d bloggers like this: