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I’ve been fortunate to have access to many of the avionics innovations introduced in the last 40 years. When Paul Ryan premiered his first TCAD, he sent me a demo TCAD 7000 unit, and I was able to see its capabilities in real time. When GPS came along in 1991, Garmin’s Tim Casey loaned me an engineering prototype of the first portable GPS 100AVD to help guide the number-one Swearingen SJ30 business jet across the North Atlantic, from San Antonio to the Paris Air Show and back.

Recently, I was granted another real-world sneak peak at a new avionics system. While I was attending the Sun ‘n Fun Show in Lakeland, Fla., Garmin gave me a two-hour introduction to the new GTN 650 and 750 systems in the company’s 2001 Mooney Ovation. Garmin product specialist and keeper of the Ovation’s keys, Dave Brown, was in the right seat to demonstrate the two radios’ capabilities, and I was flying left, enjoying the impressive combination of a great airplane and what certainly appears to be a truly innovative avionics system.

The major innovation on the 650 and 750 is the touch screen, and I was initially less than enthusiastic about the concept. Two years ago, when Garmin introduced the touch-screen, portable aera 560, I wasn’t that impressed. The company loaned me a demo unit in 2009, and I preferred the old-fashioned knobs of the 496. If you’re like me (and I know I am), and you have apprehension about the touch screen, the new 650 and 750 will change your mind. The touch screen is simpler and less troublesome than you could have imagined, but perhaps more importantly, data input and operation aren’t the 650’s and 750’s only talents.

The new GTN 650 and 750 are the company’s replacements for the old 430 and 530 (hard to think of 12-year-old avionics as “old”), and the new models incorporate an interesting combination of touch-screen and conventional controls, plus enough new features to help endear the new input method to practically everyone.


The 430 and 530 took the industry by storm at the dawn of the new millennium, and quickly became the standard by which all other avionics were measured. I installed a 430 in my Mooney in 2001, and I’ve been suitably impressed with its ease of operation ever since. Apparently, so has the rest of the industry. Garmin has sold something like 110,000 430s and 530s in the intervening years. There are only about 180,000 airplanes on the American civil aircraft registry, so 110,000 units represents a market penetration well over 50 percent. (Yes, I’m aware that many airplanes are exported, but I can personally attest that the 430 or 530 is installed in a major portion of international deliveries.)

The 650 or 750 is the logical next step in avionics development. If you’re determined to keep one foot firmly entrenched in the last century, you can do most functions twisting dials as you did with the 430 and 530, but it doesn’t take long before you begin to appreciate the new system.

It might be logical to expect I’d resist the new nav/com suites, but that wasn’t the case when I climbed into the company’s Ovation for two hours of flying around central Florida. Everyone knows an airplane cockpit makes a terrible classroom, and accordingly, I had spent an hour at Garmin’s booth becoming familiar with the system’s operating principles with West Coast Regional Manager Mike Young as my guide. In the airplane, Garmin’s Dave Brown led me by the hand through most operations.

I was far from prepared for the deluge of new technology incorporated in the 650 and 750, but at least I didn’t feel totally out of my depth when I fired up Garmin’s Mooney at Lakeland on the last day of the show. The touch-screen interface is about as telegraphic as it gets. You need only touch a menu item, and the system instantly provides you with options for that item. Fortunately, you still can do most functions the old way, a clever tactic on Garmin’s part. It means you can start using the systems immediately, programming in the familiar way; then, gradually introduce more and more touch-screen technique until you’re weaned from using knobs.

Right up front, you’ll notice that both the 650 and 750 have much larger screens than their dozen-year-old ancestors. Specifically, the 650’s screen is more than 50 percent larger than the 430’s but manages to maintain the same footprint. That’s because most of the controls are now incorporated into the screen, so many of the peripheral buttons and switches used on the 430 are no longer necessary.


The 750’s screen is almost double the size of the 530’s, about seven inches diagonally. Coincidentally, that’s the same dimension as the company’s king-sized, portable 696 GPS nav. In fact, the 750 is roughly the size of a 430 and 530 combined, so you’ll need considerable center stack space if you plan to install the two in the usual center position.

The big screen makes it possible to view an entire approach plate using Garmin FliteCharts and ChartView. You also can display integrated audio if you select the new, optional GMA 35 remote mount audio panel. In combination with the integral transponder, also optional, similar to that incorporated in the popular G1000, this can eliminate two more boxes from the radio stack, and make life a little simpler for pilots flying older, steam-gauge airplanes with limited panel space.

All this innovation makes the 750 more reminiscent of a glass-panel MFD with built-in nav and com capability than a GPS/NAV/COM in the traditional sense. The contrast between the old and the new displays is dramatic. In addition to offering a larger screen, Garmin has packed over five times more pixels into the new 750, specifically 650 x 708 (a total of 425,000), so the sharp LED display is crisp and brilliant, with all the detail you could ask for. The 650 sports a pixel count of 600 x 266 (for 159,600 total), but since the 650’s screen is smaller, resolution is still excellent.

Flying Garmin’s Ovation, I couldn’t help but notice how much more intense the display is than on the older systems. That’s not to demean the 430 and 530 (I still love my 430), but there are glare and sun-line conditions under which it’s tough to see detail on older systems. That’s not the case with the 650 and 750. I banked the airplane and flew circles to find the most adverse sun angles I could, and the display remained eminently visible.

Garmin was well aware that a major criticism of touch-screen controls in an aircraft avionics system is the inherent instability of a single finger trying to press a specific control key or keys in rough air. For that reason, Garmin installed finger-anchoring bezels on both sides of the displays and a stabilization board at the bottom. When you’re bouncing around in turbulence, you can anchor a thumb or fingers on the sides or bottom of the display, and still hit the proper key accurately. (I do the same thing on my 430’s soft keys, but it’s not as easy.)

If you opt for data entry and selection by the old method, there’s a pair of concentric knobs, a volume/squelch knob, and HOME and DIRECT TO buttons. This allows you to input frequencies and flight plans as before while accessing previous pages with the touch of a button. Using the HOME key, you can return to most primary pages in one or two clicks.

Dave Brown suggested we fly down to Avon Park Executive Airport, 40 miles southeast of Lakeland, to get away from the air-show traffic. That would allow us to test the system’s ability to couple to the autopilot and shoot an automatic approach. I pointed the airplane in the approximate direction of KAVO, and Brown coupled the system to the autopilot. Florida is fairly flat, so there’s nothing to hit if you’re above 1,000 feet, but it still was comforting to know the 750 incorporates a built-in terrain database that indicates when potential obstructions are nearby. The new Garmins are compatible with a number of autopilots, but only the Garmin 700 is available with the G1000.

On the way to Avon Park, Dave demonstrated the system’s dramatically improved processor, now faster than ever before. It seems each new generation of GPS benefits from a quicker processor, making screen changes almost instantaneous.

Fortunately, the weather was excellent for our flight, so XM WX had nothing to show us, but it was comforting to know that we would have had NEXRAD, METARs, TAFs and all the other acronyms available if we had needed them. (XM Weather requires a subscription to the service.)

If you do need to deviate for weather or ATC, it’s a fairly simple process. Pilots can edit an active route on the map itself, entering new waypoints or modifying the sequence by dragging a finger across the screen. If ATC assigns a Victor airway or high-altitude jet route, the pilot can overlay the route on the map, then modify it as necessary with a “rubber band” feature to accommodate ATC deviations as needed. If you’ve worked an iPhone, you’ll be basically familiar with the concept.

You can scroll left or right, up or down, by simply swiping your finger across the screen. You also can insert an off-course vector by simply sliding your finger to the new checkpoint; the course line will follow automatically, and the flight plan will be corrected on the planning page. (One feature Garmin didn’t incorporate was “pinch range capability,” which allows you to increase or decrease range by simply squeezing two fingers together or opening them up to expand or contract the image on the screen, another iPhone technique. Look for that as a possible improvement on a future iteration.)

Predictably, the approach to Avon Park was near perfect. The only duty for the pilot was to adjust power to maintain a proper approach speed, and extend the gear and flaps. The system drove the airplane down a pseudo ILS glidepath on a GPS approach, just as if we were flying a standard three-degree descent with a real ILS.

If I had any objection to the new systems, it might be that they seem to demand more head-down time than previous units. With the old concentric knobs, you could reference the old frequency (for example), look back outside, and count the number of clicks to reach the new number.

Just as the 430 and 530 came to dominate the avionics aftermarket, the new GTN 650 and 750 are virtually guaranteed to become the retrofit NAV/COMs of choice. To that end, Garmin has already certified the new models in several hundred GA airplanes. There’s a good chance manufacturers may select the systems for production airplanes, as well.

Garmin was actively selling the systems through several dealers at Lakeland, so they should be readily available by the time you read this. The GTN 650 has a suggested list price of $11,495, and the GTN 750 has a retail price of $16,995. Garmin’s GMA 35 remote audio panel sells for an additional $2,995.


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