EAA Sport Aviation

comm and VLOC radios in a single unit. The GTN 650 is the same exact size as the GNS 430, so it fits in panels with restricted space. The GTN 750’s overall height is 6 inches, compared to the 2. 65 inches of the 650, so it does require considerably more panel space. The 750 screen measures 6. 9 inches diagonally, and the resolution is fabulous with more than five times the pixels of the 530. Because the 750 can control a remotely mounted audio panel and transponder, those boxes can move out of the instrument panel into any available space, helping the 750 fit in most radio stacks. Actually, the part of the 750 that extends behind the panel is much smaller than the display, so the remote audio control and transponder can stack behind the display, using no more panel space.

The extra display size of the 750 allows it to be a full multi-function display showing IFR charts, Garmin’s Safe Taxi airport diagram, XM Weather, traffic, terrain, and full-capability moving maps.

Flight plan management on the GTN series is greatly simplified compared to the 430/530s. Instead of knob twisting to enter the identifier for an airport or fix along your route, you touch a keypad on the screen. The small size of the GTN 650

demands that you make two touches to call up the characters, but on the 750 a full alphanumeric keypad appears.

You can also do graphic flight planning by touching fixes shown on the moving map. Or you can use your finger to “drag” a leg of the flight plan on the map over to a different fix and enter that into the flight plan by tapping the fix. This feature will be useful in crowded airspace where re-routes are common. With the airways called up on the display you won’t need to hunt around on the chart to find the new routing you were just cleared to fly.

With the airways called
up on the display you
won’t need to hunt
around on the chart.

I think the most common use of the
graphic flight planning capability will be
when deviating around weather. You can
simply drag your route on the display over to
a point where you clear the weather shown
on the moving map and tell the controller
you want to go to that point. You can graphi-
cally move your route to any spot on the
display, not just to published fixes, and you
will see bearing and distance to that spot. So,
you could then ask the controller to deviate
left or right so many degrees for so many
miles and know that you are flying to a spot
that doesn’t show a Nexrad radar target.

Garmin's new touch-screen units were publicly unveiled at Sun 'n Fun in Lakeland, Florida in March.

TEST FLYING

To see the GTN 750/650 in the real world, Garmin’s Ben Kowalski and I filed an IFR flight plan along airways from my home base in Muskegon, Michigan, over to Lansing. The weather was marginal VFR with a ceiling barely above the 1,000-foot minimum, so we would be flying in actual conditions.