New Garmin GTN 750 Features

Garmin has released system software 6.50 (since updated to 6.51, which is a mandatory update) for its GTN 750 and GTN 650 navigators. The new software adds several features, including:

• Vertical navigation (VNAV) capability when flying STARS and the initial stages of instrument approaches
• Along-track offsets in flight plan segments
• Destination airport remains in the flight plan when an approach is loaded (but the destination airport is removed when the approach is activated)
• A shortcut to the airport info page added to all procedure headers
• Load the approach NAV frequency from the approach header in the flight plan
• QWERTY keyboard option

The following sections highlight some of these features. For more details on how to use the functions, see the latest editions of the GTN guides, available in my Aviation Documents folder at OneDrive and from Garmin’s product pages.

The details about this update to the GTN series are in ASDN Service Bulletin 1860, the 6.51 mandatory udpate, and the GTN 725/750 SOFTWARE v6.50 PILOT’S GUIDE UPGRADE SUPPLEMENT.

Garmin also released system software updates for the G500/600 PFD/MFD and associated hardware. For details on those updates, see ASDN Service Bulletin 1861.

Garmin has also updated its free Windows-based trainer for the GTN series.

Note that these system updates must be performed by an authorized Garmin dealer or avionics shop unless you are flying a experimental-homebuilt aircraft.

VNAV Capability

The new software adds several vertical navigation features, best illustrated with examples.

Garmin has published a video that describes the VNAV feature in detail, here.

Suppose you are flying the RNAV RWY 08 approach at Lewiston, ID (KLWS), joining the procedure at the BIDDY initial approach fix northwest of the airport. The NoPT feeder route from BIDDY specifies an an altitude of at or above 5000 ft to EVOYU, followed by a descent to at or above 4000 ft to MABIZ, and then at or above 3400 ft to the FAF at GIYES.

With the new GTN system software, those segment altitudes appear in the flight plan page for the procedure.

The VNAV feature appears as a magenta vertical guidance cue next to the altitude tape on a PFD such as the new Garmin G500Txi (shown here) or the G500. Note that at this point in the approach, the LPV glidepath is a dim white diamond behind the magenta VNAV cue because the FAF is not the active waypoint and LPV is not yet annunciated on the HSI.

The VNAV cue provides advisory guidance to help you smoothly descend to each charted altitude as you fly the initial stages of the approach.

The LPV glidepath marker that displays approved vertical guidance replaces the VNAV cue when the FAF is active and the GTN system confirms that LPV minimums are available, as shown below.

Similar VNAV information and cues are available when flying a STAR, such as the MADEE FOUR arrival at Bellingham, WA (KBLI).

Note that the altitudes shown in the GTN flight plan list for this STAR are for turbojet aircraft. But you can easily edit the altitude if ATC assigns a more appropriate altitude when you’re flying a typical piston-powered light aircraft.

If you are flying an approach based on an ILS, LOC, or VOR, you can quickly retrieve the navaid frequency by touching the approach title, as shown below for the ILS RWY 16 at KBLI.

Along-Track Offsets

Suppose you are flying northeast along V2 at 13,000 ft. between ELN and MWH when Seattle Center clears you to cross 20 nm west of MWH at 9000 ft.

With the new software, you can easily enter an along-track offset and display advisory vertical guidance to help you meet the restriction.

Touch MWH in the flight plan, and then touch the new Along Track button.

To create a waypoint for VNAV guidance, fill in the information that corresponds to your new clearance.

Airport Information

An earlier version of the GTN system software included behavior that frustrated many pilots. When you loaded an approach into a flight plan, the destination airport was removed. If you hadn’t noted details such as the tower frequency, extracting that information from the GTN’s database was cumbersome.

In version 6.50, Garmin has added an APT Info button next to the approach title in the flight plan list.

Touching that button shows the familiar information window that provides touch access to details about the airport, including frequencies, weather, and other data.

QWERTY Keyboard

You can also choose a QWERTY keyboard instead of the alphabetical layout in previous versions of the GTN software. The option is available on the System Setup page.

Changes to Flight Plans with Procedures in GTN System Software 6.x

Garmin has released updated system software (version 6.11) for the GTN series of navigators. The software includes several new features. One of the most important changes, at least for day-to-day operations for typical general aviation pilots, is how loading (or activating procedures) affects departure and destination airports in flight plans (routes).

To learn about and practice using the new features, download the latest version of the free GTN 750 PC Trainer Lite from Garmin. The download includes updated manuals (PDFs) for the GTN series avionics that describe the new features in version 6.x.

I have experimented with how the new system software in the free GTN 750 PC Trainer Lite available from Garmin, and the following examples illustrate the changes and offer suggestions to help you adapt your personal techniques for using a GTN-series navigator in the cockpit. In particular, I offer suggestions for displaying information about your destination airport (frequencies, current weather, and so forth).

To learn about the new ad-hoc hold feature in the updated software, see Flying Ad-Hoc Holds with a GTN 750 here at my blog.

Basics of the Change

First, here’s a note in the updated Pilot’s Guide for the GTN 750 that describes how software version 6.x changes flight plans (routes) when you load an approach (or, it turns out, a departure procedure).

Now let’s look at how this change affects when and how you load and fly a typical instrument approach.

A Typical IFR Flight Plan

Suppose you plan to fly from Boeing Field (KBFI) in Seattle, WA to Spokane International Airport (KGEG) in eastern Washington. Here’s a route across the Cascades that I often fly in my normally aspirated Beechcraft A36.

Note that the first and last waypoints in the flight plan are the departure airport (KBFI) and destination (KGEG). ATC typically assigns a SID when departing Boeing Field. When runway 13R is in use for IFR departures, your clearance includes the KENT7 (or the current version) SID, which you load as follows.

Note that after you load the departure, KBFI no longer appears as a waypoint in your current flight plan. The first waypoint in the flight plan is now the runway ((RW13R), which is the first fix in the KENT7 SID. The IDs of the departure and destination airports, however, remain in the title of the Active Flight Plan.

Here’s the first tip. If you use your GTN navigator to retrieve frequencies and other information about your departure airport, collect that data before you load a departure procedure.

Now assume that you have departed KBFI, followed the SID and ATC vectors to join V2, and proceeded to a point west of Spokane where you are preparing for the arrival and approach at KGEG, say the RNAV (GPS) RWY 21 Y approach.

Given that you’re approaching KGEG from the west, ZOOMR is good fix to choose, at least initially, as the transition for the approach. ATC will probably provide vectors, but with all the fixes from the west now in the flight plan, it’s easy to accept a clearance direct to any of the fixes or legs along the path to the final approach segment.

Notice that after you load the approach, the GTN removes KGEG from your active flight plan—unless the active leg of your flight plan includes the airport. Versions of the system software prior to 6.x always added the approach name and fixes for an approach below the destination airport.

A Logical Change?

The change in behavior in version 6.x may disrupt your habits at first. But it also may reduce the potential for errors when you load and fly an approach (or DP) under typical circumstances.

The new behavior provides a seamless transition from waypoints in en route section of your flight plan to fixes in an approach. You no longer have to scroll below the destination airport in the active flight plan list to select an initial fix or to activate a leg of the approach you’ve loaded into the GTN.

A Change in Tactics?

The new behavior described above may lead you to change your basic technique for loading an approach.

I have long advocated loading procedures as early as possible—even before taking off if the destination is nearby—to reduce your workload during busy phases of flight. The new behavior in GTN software version 6.x, however, suggests a change in tactics, at least under some circumstances.

If you can determine well in advance which approach you prefer to fly—in-cockpit weather can give you an early alert about which runway is likely to be in use long before you can receive the ATIS or AWOS (that is, the one-minute weather at a non-towered airport)—then loading the approach you prefer or reasonably expect to fly is still a good idea. Just take a moment before you load the procedure to retrieve and note frequencies and other details about your destination airport from the GTN.

Pilots arriving or departing an uncontrolled airport that has automated weather broadcast capability (ASOS/AWSS/AWOS) should monitor the broadcast frequency, advise the controller that they have the “one−minute weather” and state intentions prior to operating within the Class B, Class C, Class D, or Class E surface areas. (AIM 4-4-6)

ONE-MINUTE WEATHER− The most recent one minute updated weather broadcast received by a pilot from an uncontrolled airport ASOS/AWSS/AWOS. (P/C Glossary)

If you prefer to wait until you are closer to the airport, or if ATC clears you direct to the airport or issues vectors before initiating an approach clearance, you can delay loading the approach.

If you wait until the active leg of your flight plan includes the destination airport, the GTN adds the approach below the destination airport, just as it did prior to version 6.x.

Or, as shown below, you can load a procedure early and then add the destination airport to the bottom of your current flight plan, so that the airport is still available as a reference and to provide easy access to the information about the airport in the GTN’s database. Here I’ve added KGEG below GANGS, the MAHP for the RNAV (GPS) RWY 21 Y approach. It’s easy, as before version 6.x, to touch the airport ID and then select Waypoint Info.

Add an Alternate?

The change in version 6.x also simplifies adding an alternate to your flight plan.

Suppose the weather at KGEG is close to minimums as you begin your arrival. Adding an alternate airport to your flight plan before you miss the approach could reduce your workload during a critical phase of flight.

Here I’ve added Walla Walla, (KALW) as my alternate after the MAHP at GANGS.

Now I can quickly retrieve information about KALW and even load an approach as soon as I get a new clearance from ATC.

This technique would also be handy during training flights, when you fly several approaches, either to the same airport or close-by fields.

Other Methods for Retrieving Airport Information

If you prefer not to fuss with the way version 6.x handles airports in flight plans that include procedures, you can still retrieve information about airports from the GTN’s database, even if your departure and destination airports are no longer in your active flight plan.

For example, touch the map, scroll to display an airport, and touch an airport symbol. Touch Waypoint Info to display details (frequencies, current weather, runways, NOTAMs, and so forth) about the airport.

You can also use the Nearest Airport feature (available from the Home screen) to gain quick access to details about your destination—provided you’re not too far away.

Or you can use the various search option in the GTN to find an airport and retrieve information about it.

More to Come

I’ll have more to say about the updated system software after I’ve had it installed in my airplane and explored the new features on test flights. Stay tuned.