Tips and Tricks #28
Voice Commands to the GTN 650/750

Keith Thomassen, PhD, CFII

There is some controversy over the safety benefits of glass panels, in particular of the modern GPS navigators that provide so much information to the pilot. They have many potential benefits but they also demand a high level of skill in their use, and thorough knowledge of their capabilities to realize these benefits. Therein lies the rub; yes they should provide enhanced safety, but only if you are facile in using them. We’ve all found ourselves wrapped up in the execution of a change to our flight plan, getting information on weather, runways, etc., or finding and entering a new frequency. Clearly, the more thoroughly you’ve learned to operate your GPS the quicker you can do these steps. Nonetheless, they are time consuming and can interrupt your scan and divert your attention from tasks at hand.

So it is a welcome addition of voice commands that Garmin has added in their touchscreen navigators. There are currently 178 different commands that can be executed by a push of the button and a short statement into your Mic. These are big timesavers, and further they are very useful in turbulence. There are 87 commands to “Show Page”, 23 to “Show” data, 22 to “Say” data, 26 to “Tune” a frequency and 16 to make Audio panel changes. (Some of these require other equipment, like a GTX 345, GDL 69, or the GMA 35 or 35C audio panel). You can also Zoom in or Out, and Scroll Up or Down. A selected list of their commands is shown here, but you can see the whole list in the Touchscreen manuals. (Search for Telligence Voice Command Manual to see all of them). You first need to train the unit to your voice on 20 specified questions. To use these commands be sure to say them exactly as written here.

Show (x) Page: x = Home, Map, Traffic, Flight Plan, Procedures, Approaches, Arrivals, Departures, Charts, Waypoint Info, Airport Info, Nearest, XM or FIS-B Weather

Show Nearest (x) Page: x = Airport, VOR, Airspace, Center, FSS, Weather Frequency

Show Destination (x) Page: x = Info, Weather, Frequencies, Procedures, Runways, Notams, Preview

Show: Distance, Ground Speed, ETA or ETA, ETE to Destination, ETA at Destination, Distance to Destination, Time to Descent

Say: ETA, ETE, ETA at Destination, ETE to Destination, Distance, Distance to Destination, Bearing and Distance From Destination Airport, Time to Descent, Winds, Ground speed, Current Time, Fuel Flow, Timer, Current Time, OAT

Tune Nearest: Tower, Unicom, Approach, Departure, FSS, ATIS (or ASOS or AWOS), Ground, Clearance, CTAF, Center, Weather [finds nearest ATIS (or ASOS or AWOS)]

Tune Destination: Tower, Unicom, Approach, Departure, FSS, ATIS (or ASOS or AWOS), Ground, CTAF, Weather (finds ATIS (or ASOS or AWOS)

Audio Panel: Select MIC One (or Two), Toggle COM One (or Two), Show Pilot (Co-pilot, Passenger) Volume, Turn Pilot (Co-pilot, Passenger) Volume Up (Down)

To illustrate some of these, let’s take an expensive hamburger flight, starting from KSAC, a towered airport in Sacramento. We’ll go to KRBL, a non-towered airport in Red Bluff, which has a good restaurant (a 45 min flight in my C210).

After startup, but before entering a flight plan, we “Tune Nearest Weather”, which will put the KSAC ATIS frequency 125.5 in Standby in COM 1. Flip into Active, then “Tune Nearest Ground” to put that in Standby. After listening to the ATIS flip Ground to Active, then “Tune Nearest Tower”. It is annoying that you cannot flip the frequencies with a voice command, but Garmin is planning to add that feature in a later software update. Now, “Show Flight Plan Page” to enter KSAC and KRBL. Then “Show Map Page” and taxi out. After run up, flip Tower to active and “Tune Nearest Departure” which will put 127.4 in Standby. Verify that this is what you’re given for flight following.

On the way to KRBL, you may want to check the weather at nearby airports, so use “Show Nearest Weather Frequency Page” to see the nearest 25 airports reporting weather. There you can touch either one of the airports in the list to get its Info page, or touch the frequency to put it in Standby. Or, you may want the nearest 5 ARTCC frequencies so then you would “Show Nearest Center Page”. You can also “Show Nearest FSS Page”.

After 30 min we want to check progress so we “Say Destination ETE” and are told (in a very pleasant voice) that you are 15 min to your destination. We could also ask for Distance or ETA, or “Show Destination Preview Page” to view the airport environment. At that point, in preparation for landing at KRBL, we “Tune Destination Weather” to put the ASOS frequency 120.775 in COM 1 Standby. We could have said “Tune Destination ASOS” but didn’t know whether it was an AWOS (owned by NWS) or ASOS (owned by airport or State). ATIS is usually only at towered airports. By saying Destination Weather it chooses for us.

Perhaps you’ve noticed that you cannot monitor the Standby frequency in a GTN, unlike most other GPS or NAV/COM units. Instead, the Monitor function listens to a second COM 2 that’s coupled to your GMA 35 audio panel. You can put this ASOS frequency in it (you have to do it manually, but you can just copy it from COM 1). Put it in Active then “Toggle COM Two” to monitor the ASOS there. Toggle again to turn off monitoring. Note that if your only COM is on the 750 (no COM 2), to monitor the ASOS you have to go off frequency and flip Standby to Active.

When released from flight following, you then “Tune Destination Unicom” and flip it to active for advisories at KRBL. If you land at a towered airport say “Tune Destination Tower”. Then, you can also “Tune Destination Ground after switching Tower to Active.

Clearly, there is a lot of time saving even in this simple flight, but none of these had to be done at a busy time. The command system really shines when you are busy. As an example, on a round robin training flight with approaches at multiple airports, transitioning from one missed approach to do another approach at a different airport requires many changes in a short period of time. On the hamburger trip we decide to do an approach at KRBL then do the missed and shoot an approach at Chico (KCIC) and land for lunch. So before entering the Terminal flight phase (30 nm from KRBL) just “Show Destination Procedures Page” to select then enter an approach and transition (the Destination airport is already selected). After you Load or Activate it, according to the circumstances, use the commands above to manage the frequencies you need for ASOS and Unicom.

On the missed approach, change back from Unicom to ATC (which should be in Standby). While in the Hold, you can prepare for a change in plans to KCIC and add an approach. So, “Show Flight Plan Page” and add KCIC after KRBL, then “Show Destination Procedures Page” to choose the ILS 13L with the RBL transition. Alternatively, you could simply add an approach at KCIC without first adding KCIC to your flight plan. Just “Show Approaches Page” and you will get the page with the Airport, Approach, and Transition Options. Now select KCIC, ILS 13L, and RBL on that page. In this case however, you don’t have the option to simply Load it as in the first method, with KCIC in the flight plan as a new Destination. Now, you must Load and Activate. Also, without this new Destination in the flight plan you can’t use the Destination commands to load frequencies for KCIC. This illustrates a point, that there are generally several ways to do things in the GTN’s, and before these voice commands appeared you simply learned the shortest way to do it (right?). Now you need to know the smartest way to do it that lends maximal support to the Voice commands.

Next, while in the Hold, “Show Map Page” for situational awareness. To leave the hold and make an active leg, you would say “Show Flight Plan Page”. Now, initiate the approach by either activating it (go D-> RBL) or some other action to move on, such as D-> another waypoint on the approach.

You are not far from the Terminal area, so “Tune Destination Weather” to listen to the ATIS at KCIC. Other frequencies for KCIC can now be loaded using the commands we discussed.

These are just a couple of examples of ways that you can reduce your “heads down” time to make changes in the GPS. Clearly, voice commands can be a valuable addition to your flying. If your shop didn’t install this, simply add a push to talk switch (actually, it will be labeled PTC for push to command) on your yoke. One wire to the 750 will do it. Personally, it has be one of the best GPS options in awhile, and its lots of fun.