In Support of the GNS 480

I feel a bit like Senator Claghorn, pausing to adjust the papers on the podium before raising my eyes to the gallery and in deep, mellifluous tones saying, "With deep respect for my colleague across the aisle, I rise in support of the Garmin GNS 480." In the interest of full disclosure, I have to acknowledge that I've been a strong proponent of the 480 ever since I had one installed in the panel of my Cessna Cardinal. So, the announcement by Garmin in December that it was discontinuing the 480 came as a real disappointment for me and other pilots flying with the 480. It may be too late, but I want the 480 to get the posthumous recognition it justly deserves.

I've grown tired of the 480 being maligned and ignored. Mac, my colleague across the aisle, in his Left Seat column ("WAAS Made Easy") in January, described how easy it is to fly WAAS approaches with vertical guidance. While touting the WAAS capabilities of the Garmin 430W/530W and the G1000, Mac never mentioned the Garmin GNS 480, née UPS CNX 80. In Mac's defense, the installed base of the 430/530 navigators is approximately 10 times that of the 80/480. But those of us, the few, the proud, flying with the 480, want to be recognized. As an option for upgrading a conventionally equipped panel, the 480 has deserved serious consideration.

As good and as popular as they are, Garmin's 430W/530W came late to the party. Way back in the spring of 2003, UPS Aviation Technologies introduced the CNX 80 with a WAAS processor that updated five times a second instead of the then standard of once a second. And then in 2004, Garmin further enhanced the CNX 80 with a software update that allowed it to calculate vertical guidance for VNAV and LPV approaches. In the meantime, Garmin was continuing to work on a WAAS engine for its 430/530 navigators; it was a long time coming.

But unfortunately, the 480 got a bad rep right out of the box. I think much of its slow acceptance by the market, despite its WAAS capability, was because it entered the race of integrated navigators way behind Garmin's 430/530 that were, by the time the 480 made its debut, well ensconced in a plethora of panels. Competing against the popularity of the 430/530 was an uphill battle.

Radio shops, confident of their customers' satisfaction with the 430/530 boxes, were reluctant to recommend a unit with which they weren't as familiar. Typically, when a customer asked an avionics shop about the CNX 80, the stock response was something on the order of: "If you're going to be doing serious IFR flying, then the 480 may make sense, but it uses a different interface than the 430/530 that isn't as user friendly, so the 430/530 is the way to go." As a result, customers were hesitant to sign up for something their installers were promoting only half-heartedly.

And then there were the rumors that circulated at AirVenture 2003 that Garmin was considering purchasing UPSAT. The assumption that many of us made was that Garmin wanted to acquire UPS's Aviation Technology division for the advances it had engineered in its WAAS box. Feeding the market malaise was the feeling that Garmin was acquiring AT in order to kill off the competition. To reassure pilots Garmin announced that it was fully behind the CNX 80 and, as its ads stated, "We're putting our name on the front so pilots can fly behind it." Nevertheless, despite Garmin's assurances that it would keep the 480 in its product line and continue to support it, the concern was enough to further depress sales of an integrated navigator that those of us who knew and loved it felt had features, aside from the WAAS capability, that set it apart from Garmin's already popular favorites.

So, what does the 480 offer that makes those of us "flying behind it" feel it was the better choice to occupy precious panel real estate?

One of the impressive things that set the 480 at the head of the class is the airway flight planning feature. Ironically, it's probably that single feature that fostered the impression that it was okay for serious IFR but too complex for your average pilot. That was a false impression.

The flight planning function is simple. After you select your departure and destination airports you can build the flight plan either from waypoint to waypoint or along airways. If you choose the airway option the smart keys change to represent all the airways that are available from your departure point or a nearby waypoint. Once you select an airway all the intersections and VORs along that airway are listed alphabetically. Selecting the VOR or intersection that ends your leg on that airway again brings up a choice for another airway or a waypoint.

If you don't connect all the "dots" between the last point on the airway and your destination, a "discontinuity" is inserted into the flight plan. Unfortunately, the term has disconcerted some pilots new to the box. Essentially the discontinuity means that you haven't told the 480 how you want to get from the last waypoint you selected to your destination. Deleting the discontinuity by highlighting it and pushing the "CLR" key tells the 480 that you want to go direct between the last waypoint and your destination.

If a controller is cooperative and offers you a short cut, you only have to select the flight plan (FPL), scroll down to the waypoint to which you're now cleared and push the dedicated D> key and then the DIRECT smart key.

When pilots are first introduced to the 480 they are sometimes confused by the use of the D> (direct) key. When you push the D> key you're offered a number of smart key options (DIRECT, HOLD, DEST(ination), FlyLeg, CrsTo, CrsFrom, and OBS). The DIRECT option lets you select a waypoint from the flight plan or database to go to, HOLD allows you to establish a hold at any VOR or intersection and define the direction of turns and the distance or time for the inbound leg. The 480 will direct an autopilot to "fly" holding patterns and procedure turns.

It's the DEST option that has caused some misunderstanding for new users. If you select a new airport and push the DIRECT smart key, the 480 thinks you've added the new airport only as a waypoint, not a change of destination. If you want to change your destination (and load an approach) after pushing the D> dedicated key, you have to select the DEST smart key instead of the DIRECT smart key.

With an approach loaded, all the waypoints that define the approach are listed when you view the flight plan. Selecting any of the approach waypoints (except the runway end) and pushing the D> key and then the DIRECT key will shortcut the approach to that point. There is also a VTF (Vectors to Final) option that can be selected at any time an approach is loaded and draws an extended centerline to the runway.

If it becomes necessary to perform a missed approach, the 480 displays the altitude to which you have to climb after reaching the missed approach point (MAP) and before you can safely make any turns.

If you have the JeppView option, then the 480 offers another advantage over its Garmin stablemates. When an approach is selected in the 480 the chart is automatically loaded into the MX20 or the GMX 200 multifunction display. The 430/530 navigators require the chart to be loaded from the MX20 or GMX 200 menu system. It works, but it's a bit more cumbersome.

Another feature of the 480 is the ability to monitor both the communication and navigation standby frequencies. Selecting the MON function on the comm radio allows you to listen to the standby frequency. Any time there's activity on the active frequency, the standby is muted and the active takes priority, so you can listen to an ATIS or AWOS broadcast and not worry about missing a call from the controller. The navigation monitor function shows the radial and the distance from the standby VOR in the nav box, allowing you to establish an intersection or determine where you are along an airway in relation to a VOR off to the side. The feature is particularly handy if a controller asks you to report crossing a radial from a VOR.

To further its situational awareness assistance when an approach is loaded, the 480 displays an arrow that points to the runway end and the distance to the runway in a window in the lower left-hand corner of the screen. As you maneuver during the approach you're constantly apprised of your position relative to the runway end. That's handy.

Audio callouts are another 480 feature. The box announces "500 feet," "missed approach point," and if an ILS approach is loaded, "localizer alive." The "500 feet" callout is handy for a final warning to check that your gear are down.

The 480, unlike the 430/530 navigators, has a NAV page that displays an HSI with a glideslope when an ILS or VNAV or LPV approach is loaded. Using the 480's ability to customize the data fields on the four different map pages, I've set my NAV page to show, in addition to the comm frequencies, the GPS VS (vertical speed), BRG (bearing), TRK (track) and ALT (altitude). Information I've found useful to have at hand during an approach.

As disappointing as Garmin's decision to discontinue the GNS 480 is, most of the members of the GNS 480 Users Group on Yahoo do understand the reasons. Nevertheless, they're angry that more effort wasn't put into marketing the 480 when it, partnered with the MX20 and now the GMX 200, outperformed the competition. The good news is that we're going to be able to continue to appreciate our 480s, since Garmin has promised that it plans to "preserve sufficient parts in stock to service the thousands of units in the field for years to come..." And now, I yield the remainder of my time.


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