January 19, 1998 Two Mid-Priced GPS Handhelds: Garmin GPS III Pilot & Magellan SkyStar

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by	Mike Busch

About the Author ... Mike Busch is editor-in-chief of AVweb, a member of the technical staff at Cessna Pilots Association, and in a prior lifetime was a contributing editor for The Aviation Consumer and IFR Magazine. A 6,000-hour commercial pilot and CFI with airplane, instrument and multiengine ratings, Mike has been flying for 36 years and an aircraft owner for 33. For the past 14 of those years, he's owned and flown a Cessna T310R turbocharged twin, which he maintains himself. In his never-ending quest to become a true renaissance man of aviation, Mike's on the verge of earning his A&P mechanic certificate. Mike and his wife Jan reside on the central coast of California in a semi-rural area where he can't get DSL or cable TV.

This article has been a long time coming. Since Magellan announced their new "SkyStar" handheld GPS at Sun 'n Fun in April 1997, AVweb received hundreds of reader requests asking us to review the new unit. Unfortunately, Magellan's introduction of the SkyStar turned out to be about four months premature. Deliveries didn't actually begin until August (at Oshkosh).

Shortly before Oshkosh, while I was anxiously waiting to get my hands on a SkyStar to review, Garmin unexpectedly announced a new handheld with the unwieldy name of "GPS III Pilot" and this was no pre-announcement: Garmin shipped a whole bunch of these units to Oshkosh for their dealers to sell at the show, and mailorder dealers had the new GPS IIIs in stock shortly afterwards.

With both of these new handhelds becoming available simultaneously and priced identically ($799 list, $699 street price), I figured this would be a real toe-to-toe competition. But when I finally was able to put the SkyStar and GPS III Pilot through their paces, I found the two models about as different as they could possibly be. Even the similarity in price turned out to be illusory. And both radios turned out to be disappointing in some respects.

(Three months after Oshkosh, Magellan dropped the price of the SkyStar by $110, giving it a far more competitive street price of $589.)

Some Initial Disappointments

My biggest disappointment with the new Magellan SkyStar was its total lack of ground mapping capability. As AVweb readers know, mapping of ground features such as roads, rivers, lakes and railroad tracks was first introduced to the aviation handheld market by Lowrance Electronics when they introduced their innovative AirMap handheld GPS in April, 1996. Garmin quickly followed suit with their superb GPSMAP-195 handheld in August, 1996, and II Morrow even added a relatively crude ground mapping capability to their venerable Precedus handheld. After flying tens of thousands of miles using the AirMap and GPSMAP-195, moving maps without ground mapping strike me as being terribly primitive and anachronistic.

So I was disappointed to find that Magellan's latest entry offers no ground mapping capability whatsoever, and that its display lacks the necessary resolution to allow Magellan to add such capability as future enhancement. As you'll see as you read on, Magellan has introduced a number of novel and useful features in the SkyStar. Although I've given poor marks to previous Magellan handhelds, the SkyStar is clearly a big improvement over its predecessors, and I was really hoping to give it a gold star review. But for me, the lack of ground mapping is a very serious shortcoming. On the other hand, if ground mapping isn't as much of a "hot button" for you as it is for me, you might really like the new Magellan.

I've been a huge fan of Garmin's aviation handhelds since they introduced the GPS-90 in 1995, and was blown away by the top-of-the-line GPSMAP-195 that they introduced at Oshkosh 1996. I didn't make it to EAA this year, but friends who checked out Garmin's new GPS III Pilot at Oshkosh told me that it was basically a GPSMAP-195 in a smaller, much less expensive package, and I got really excited about that.

But when I finally had the chance to evaluate the GPS III Pilot myself, I found myself disappointed once again. While the unit has a superb GPS receiver, superb software, and a superb display with excellent ground mapping capability, it became immediately apparent that the GPS III hardware was designed for motor vehicle use, not aviation. The keypad is so tiny that using it is not particularly easy even sitting in my living room, and trying to do so in the cockpit during light-to-moderate chop borders on the impossible.

Another big disappointment is that the GPS III Pilot comes with none of the basic accessories that are standard equipment on virtually every other aviation handheld. No yoke mount, no remote-mount antenna or antenna cable, no DC power cord, no carrying case. By the time you add these essentials, you've added a bit over $200 to the purchase price of the GPS III Pilot. So instead of a $699 street price, you're looking $900 and change.

Well, enough of my visceral reactions. Let's take an in-depth look at the various facets of these two new GPS handhelds.

Hardware Comparison

Size and Appearance

The Magellan SkyStar is a medium-sized handheld: a good deal bigger than a Garmin GPS-90 but not as large as a GPSMAP-195 or Lowrance AirMap. Dimensions are approximately 2.5" wide, 6.2" high, and 1.5" deep. To me, the SkyStar's size and shape feels "just right" in the hand, and its sleek rounded look is a huge improvement over Magellan's earlier boxy handhelds. The unit weighs in at 14 ounces (including batteries), giving it a comfortable heft but much less than the 22-ounce GPSMAP-195 or AirMap. All in all, this is one of the most attractive packaging jobs I've ever seen in a GPS handheld.

By comparison, the diminutive Garmin GPS III Pilot is shockingly petite. My first impression upon taking it out of the box was that this was a toy, not to be taken very seriously. (That impression changed quickly once I turned the radio on, however.) Dimensions of the unit are 2" wide, 5" high, and 1.25" deep, and weight with batteries is just nine ounces. Each of its dimensions is roughly two-thirds of the GPSMAP-195, which means that the GPS III Pilot occupies less than one-third of the volume of its big brother. The photos may not convey just how small this unit is.

The little Garmin has an unusual triangular cross-section that was specifically designed to allow the unit to sit on the dashboard of an automobile, but the shape is rather awkward for cockpit use unless the aircraft has an unusually low glareshield. On the other hand, the III is so tiny that it can be adapted to mount in places that wouldn't work for larger units (e.g., on a doorpost).

Both units have sealed plastic cases. The Magellan's projects a quality look-and-feel while the Garmin's conveys more of a toy-like appearance than other Garmins. But both models appear to be very well made and relatively rugged.

Display

Despite the fact that the GPS III Pilot is physically much smaller than the SkyStar, I was amazed to discover that the two handhelds have almost exactly the same size displays: about 1.5" by 2.2" for the Garmin and 1.6" by 2.1" for the Magellan. (Magellan's spec sheet says the display is 1.8" by 2.3" but my measurements of the useable display area came in 0.2" smaller in both dimensions.) Moreover, the display on the little Garmin seems to have higher resolution (at least I found it a lot easier to read) and the same four-level grayscale capability that gives the GPSMAP-195 such superb mapping capability. The SkyStar display appears to be strictly black-and-white, with no grays.

Neither company has released detailed specifications on the displays giving the pixel size or total resolution in pixels. But you can judge the difference for yourself by looking at the screen shots above, which appear at identical magnification. (In case you're curious, I obtained these graphics by placing the two handhelds face down on an HP flat-bed color scanner.)

A novel feature unique to the Garmin GPS III Pilot is its ability to flip the display orientation between horizontal and vertical. The idea is that you can set the display orientation to horizontal (landscape) for dashboard or glareshield mounting, and change it to vertical (portrait) for handheld or yoke-mounted use. The transformation between one orientation and the other is accomplished simply by pressing and holding the PAGE key for a second or two. Pretty slick!

Both radios have backlighting for nighttime use that illuminates both the display and keypad. The Magellan offers two levels of white backlighting; the Garmin offers three levels of green backlighting. Both are very good, although I felt that the Garmin's additional notch of dimming is a bit better for use in very dark conditions (e.g., flying over an unpopulated area on a moonless night).

Keypad

While the tiny GPS III Pilot has a surprisingly large and crisp display, the real casualty of its small size is the keypad. The Garmin's keypad consists of a four-way cursor-control rocker surrounded by eight tiny function buttons, each only about a quarter-inch in diameter. The keyboard layout is very similar to the GPSMAP-195 except that the GPS III Pilot has two keys fewer (the dedicated NRST and WPT keys of the 195 have been eliminated, and their functionality folded into the GOTO key). The keytop legends on the eight little buttons are skewed at a 45-degree angle so that they're readable whether the unit is mounted in vertical or horizontal orientation.

I found the tiny keys of the GPS III Pilot to be somewhat challenging to use when sitting at home in my Lazy-Boy, and moderately difficult to use in-flight. I haven't had the opportunity to use the radio in turbulence yet, but I suspect it would be damn near impossible.

The Magellan SkyStar uses a similar keypad layout with a four-way rocker plus ten function keys, but the keys are nicely sized and spaced and considerably easier to use. You can see the big size difference in the photos above, which appear at identical magnification (about twice actual size on my display, but your mileage may vary).

The SkyStar's keypad is below the display (where I think it belongs for yoke-mounted operation), while the GPS III Pilot's keypad is above the display (just as it is on other Garmin handhelds). When the GPS III Pilot is oriented horizontally, the keypad is to the right of the display.

Battery

Both units are powered by four AA-size alkaline batteries. Magellan claims 10 hours to a set of batteries, while Garmin claims 8-10 hours. In my tests, I was able to get a full 10 hours on a set of Duracells with both units.

If you prefer rechargeable batteries (as I do), Magellan offers an optional NiMH battery pack for $39 which powers the unit for 8 hours and is rechargeable while in the radio (including while in-flight and operating off ship's power). The GPS III Pilot can be loaded with rechargeable NiCd AA batteries (which last about 5 hours) but has no provision for in-unit recharging.

The GPS III Pilot has a nice thermometer-style battery level indicator right on the satellite status page, making it very easy to keep tabs on the state of the battery. The Magellan has a similar battery gauge but it requires more than five keystrokes through the menus to display it. On the other hand, the Magellan automatically pops up an alert box when it thinks that there's only an hour of battery life left; the Garmin has no similar alert.

Antenna

The SkyStar uses a patch-style antenna which unfolds from the back of the unit. For remote-mounting, the antenna slides off the radio and attaches to a suction-cup mount with a nine-foot coaxial cable (included). Detaching and reattaching the antenna is relatively easy, but the small antenna connector looks like it might not be hard to damage if you're not careful.

The GPS III Pilot uses a stick-style quadrifilar antenna that mounts to the radio with a standard full-size BNC connector. In the past, I've not been a big fan of stick antennas because they're awkward and tend to lose a lot of signal strength if not mounted absolutely vertically. But the GPS III Pilot antenna is much smaller than other stick antennas, and its receiver is so good that it retained a good position fix even when I intentionally positioned the antenna horizontally or even upside down.

But I consider a remote-mounted antenna to be essential for yoke-mounted use (unless your airplane has a full canopy), and the GPS III Pilot does not include a remote mounting kit. Garmin will sell you a remote-mount antenna with an eight-foot cable for an additional $127.25.

Mounting Bracket

The Magellan SkyStar comes with a nifty yoke mount that attaches to most control yokes and will also work on a control stick. It's compact, attractive, adjustable, and has a quick-disconnect feature that makes it a lot easier to install and remove than most other yoke mounts I've tried.

The GPS III Pilot does not include a yoke mount as standard equipment. It does come with a "dashboard mounting bracket" that's obviously intended for motor vehicle use but may work as a glareshield mount on some aircraft. I didn't find glareshield mounting to be acceptable on my airplane, however; the glareshield is too high and places the unit too far away for my taste, and the display is hard to read under some ambient light conditions.

Garmin sells an optional yoke mount for $90, or a complete "yoke mount kit" for $204.55 that includes a yoke mount, remote-mount antenna, and cigarette lighter power cord. I'd consider the yoke mount kit to be essential for most pilots, so I consider the $699 street price of the GPS III Pilot to be misleading; the real price should be $903.55.

Software and Database Updates

Both the SkyStar and the GPS III Pilot allow their Jeppesen databases and operating software to be updated in the field by hooking the radio to an IBM-compatible PC via a special data cable and uploading the update from diskette. Magellan charges $99 for updates, while Garmin charges $130.

The SkyStar offers two alternative Jeppesen databases: North America and International (which covers the rest of the world). The GPS III Pilot offers three Jeppesen databases: Americas, Atlantic International and Pacific International. The radios only have enough memory to hold one of these databases at a time, but if you're a world traveller you can switch from one database to another quickly by uploading from a PC over the data cable.

Software Comparison

Both units are loaded with features, most of which are implemented in software. Since both allow the software to be updated in the field, you can expect a steady stream of feature enhancements to both units as time goes on.

Menus

The GPS III Pilot uses the same "context-sensitive" menu system that it pioneered in the GPSMAP-195. Pressing the MENU key brings up one of several alternative menus depending on which nav page was being displayed when you pressed the key. If you press MENU while looking at the map page, a map-option menu pops up; if you do the same thing while looking at the active route page, a route-option menu appears; etc. In all cases, pressing MENU a second time brings up the main menu. It takes a little while to get accustomed to this system, but it is a great keystroke-saver.

I found the menu system of previous Magellan handhelds to be terribly confusing, so I was very pleased to see that the SkyStar adopted an easy-to-use context-sensitive menu system that almost looks as if it was copied from Garmin. Pressing the MENU key once brings up a specialized menu for the nav or map page being displayed, while pressing MENU a second time brings up the main menu.

I still found the SkyStar menu system a bit less-well human-engineered than the Garmin, however. The SkyStar's main menu is too big to fit on the screen at one time, and it takes a lot of keypresses to reveal some of the later menu items. There are also a number of commonly-used functions that require a lot more keypresses to access on the SkyStar than on the Garmin units (e.g., satellite status, display contrast adjustment, battery gauge). Fortunately, these minor gripes are all things that could be easily fixed by Magellan in future software releases.

Navigation Pages

The GPS III Pilot has six nav pages:

• Satellite status page (including battery gauge)
• Nav data page (6 customizable nav data fields plus heading, lat/lon, and date/time)
• Map page (moving map plus 4 customizable nav data fields)
• HSI page (HSI display plus 4 customizable nav data fields)
• Highway page (highway display plus 4 customizable nav data fields)
• Active route page

You cycle forwards through the six pages by pressing the PAGE key; you can also cycle through them backwards by pressing the QUIT key.

The nav data is highly customizable. You can choose each nav data field (six on the nav data page and four each on the map, HSI and highway pages) from a long list of available fields, and set up the pages almost any way you like. The biggest shortcoming I found was that a CDI (course deviation indicator) display is not available on any of the pages. The closest you can come to a CDI with the GPS III Pilot is to display a "pointer" (sort of a poor man's ADF needle) and a cross-track error distance (a digital field that shows how far off-course you are). I'd really like to see Garmin add a CDI option in a future software enhancement.

Here's an example of where the GPS III Pilot suffers in comparison to its big brother GPSMAP-195 because of its smaller display size. The GPSMAP-195 will display up to eight nav fields (or six fields plus a CDI) on its moving map page, giving you all the information you need to fly without having to switch pages. The GPS III Pilot displays only four nav fields on its moving map page (e.g., distance to next waypoint, groundspeed, bearing and track), which is just not enough, so you'll find yourself toggling back and forth between various pages quite frequently.

The Magellan SkyStar has eight nav pages:

• Position page (3 customizable nav data fields plus lat/lon, altitude and time)
• Navigation page (6 customizable nav data fields plus CDI)
• HSI page
• Descent profile page (only if VNAV is activated)
• Fuel page (only if route is active and fuel burn info has been entered)

• Full map page (full-screen moving map)
• Half map page (moving map plus 6 customizable nav data fields)
• Pan N Scan map page (full-screen moving map plus cursor)

The NAV key cycles through the first five of these pages, while the MAP key cycles through the last three. Just as with the Garmin, the nav data fields are highly customizable. A CDI display is available on the navigation page, but not on the moving map page (where I'd really like to see it).

A nice feature of the SkyStar is a status line at the bottom of every display page that reminds you of various important things: whether the unit is in simulator mode or actually tracking satellites, whether the GPS position fix has been lost or degraded to 2D, what the current map scale (zoom level) is, and whether the "autoscale" mode is active. I wish Magellan would add a battery-level indicator to the status line.

Ground Mapping

The ground mapping capability of the GPS III Pilot is simply outstanding. It's every bit as good as the GPSMAP-195 (which has the best ground mapping on the market) except that the display area is smaller. The GPS III Pilot's razor-sharp high-resolution display with four-level grayscale capability provides an easy-to-read map that looks very much like a sectional chart (albeit in monochrome). Once again, the Garmin hardware and software gurus have done a really splendid job. About the only thing missing is depiction of obstacles and their elevations, a feature which so far is offered only by the Lowrance AirMap.

As mentioned previously, the Magellan SkyStar has no ground mapping capability at all, which I consider perhaps its single biggest shortcoming. It does provide a moving map display that includes airports, navaids, intersections and sectorized special use airspace. It's an adequate map, with higher resolution than a Garmin GPS-90 or the earlier generation of Magellan handhelds or the pre-ground-mapping IIMorrow Precedus. But it hardly holds a candle to the AirMap or GPSMAP-195 or even the GPS III Pilot. I was frankly surprised that any manufacturer would release a new product in 1997 without ground mapping capability, but maybe that's just me.

Neither unit has any provision for plug-in regional mapping cartridges like those supported by the GPSMAP-195 and AirMap. I don't consider this to be a significant issue for aviation use, although regional mapping cartridges can be very useful for terrestrial applications.

Zoom and Auto-Zoom

Both units allow you to zoom the map in or out at will. The GPS III Pilot has dedicated "IN" and "OUT" keys for this, while the SkyStar uses its four-way rocker for to control zooming. I found Garmin's approach of having dedicated zoom-in/zoom-out keys to be more user-friendly (although I sure wish those keys were bigger).

The GPS III Pilot provides an enormous range of map scales, from about 500 feet to 5000 NM. The maximum zoom-out lets you see the entire North American continent at once (or all of Europe and the U.K.), while the maximum zoom-in lets you see what taxiway you're on.

The SkyStar zoom provides eleven ranges from .25 NM to 250 NM. This is fine for most in-flight use where the 250 NM scale provide plenty of look-ahead unless you're flying an SR-71. But wider looks are sometimes useful during flight planning on the ground to answer questions like "does my route from Cincinnati to Tulsa pass through Arkansas?" I don't consider this a big issue, however.

When you zoom in or out, the map display has to be redrawn at the new scale. The GPS III Pilot and SkyStar have comparable redraw speeds, and sometimes take three or four seconds to redraw the new map. The delay can be annoying, although it is on a par with other handhelds like the GPSMAP-195 and Precedus. The Lowrance AirMap is the only handheld I've seen that can consistently redraw its map in one second or less.

Both models offer an "auto-zoom" feature that lets the software automatically adjust the zoom range to display your current route segment, zooming in automatically as you near the fix, and zooming out once you've passed the fix to let you see the next route segment. (Magellan calls this feature "autoscale.") This is an extremely useful feature and I find myself using it most of the time when in-flight. Both models handle auto-zoom well. The SkyStar includes an "A" on the status line at the bottom of the map pages to remind you that autoscale is active, a nice touch.

Track History

Both units will plot a track history on the map display so that you can see where you've been. But the SkyStar has a tiny 24-point track history memory buffer. This means that if you instruct it to capture your position every 25 seconds, the unit can only remember the last 20 minutes' worth of track history. And if you ask it to remember your track history for the last two hours (the maximum setting), it will only capture your position every 5 minutes. This may be sufficient for some users. But as a CFI, I like to use GPS track history to review a lesson on instrument approaches or holding patterns after we get on the ground, and the SkyStar's small track history buffer just won't cut it.

De-Cluttering

Both units include de-cluttering software that eliminates progressively more and more map detail as you zoom out to wider scales. This is necessary to keep the map legible. The SkyStar's de-cluttering function is largely hard-wired, while the GPS III Pilot permits the user to customize the de-cluttering algorithm by setting the scale at which various kinds of map details are eliminated. But there are so many parameters to customize that in practice, most users won't be inclined to fiddle with them. The default settings work okay.

Cursor/Pan Mode

Both models provide a capability for slewing a "cursor" around the moving map display. This is used for two purposes: to point to something on the map in order to get more information about it or to memorize its position or to navigate there, or to "pan" the map window by slewing the cursor beyond the edge of the usual present-position-centered display. This is an important and often used feature.

The GPS III Pilot has a very nice cursor mode that works just like the GPSMAP-195. To activate it, you simply press the four-way rocker key while looking at the map page. A "bullseye" cursor appears and you can slew it around the map with the rocker. As the cursor touches various map features, up pops a little label telling you what that feature is: "R-4502A", "Interstate 40", "Russian River", "Union Pacific RR", "Lake Winnebago" or what have you. This is a wonderful feature.

When you slew the GPS III Pilot's cursor off the edge of the map window, the whole map smooth-scrolls as necessary to keep the cursor on-screen. If you slew too far beyond the original map display, however, you'll run into a redraw delay.

Once you've placed the cursor where you want it, you can ask the GPS III Pilot to:

• Navigate a great-circle route to the cursor position
• Create a user-defined waypoint at the cursor position
• Zoom the map in on the cursor position to have a closer look

To leave cursor mode, you press the QUIT key. The bullseye disappears and the map re-centers on your present position.

The SkyStar cursor mode is very crude and ugly by comparison. Because the SkyStar lacks dedicated zoom-in/zoom-out keys and accomplishes zooming with its four-way rocker, Magellan had to provide an entirely separate map page just to support cursor mode and panning. The "Pan page" looks just like the regular full-page map display except that it has a little cross-shaped cursor in the middle. To move the cursor, you must first place the page into "Pan N Scan" mode by selecting a menu function or pressing the ESC key. Once in "Pan N Scan" mode, the four-way rocker allows the cursor to be moved around the map. Unfortunately, cursor movement occurs is anything but smooth; it occurs in large, jerky increments which I found most disconcerting. And rather than the cursor moving on the map, the map moves under a stationary centered cursor, and then the newly revealed portion of the map is redrawn while you watch.

To zoom the map to a different scale, you have to exit "Pan N Scan" mode, change the zoom scale with the four-way rocker, and then re-select "Pan N Scan" mode. Yuck!

I found the SkyStar's implementation of cursor mode and panning to be very unfriendly. There's no doubt in my mind that Magellan's software whiz-kids can do better than this (even without having zoom-in/zoom-out keys on the keypad), and I hope they'll give this area some real attention in the next software release.

Route Mode

Both models offer a route mode which enable you to set up multi-waypoint routes and have the GPS automatically sequence from segment to segment as you fly. Both allow you to store up to 20 such routes in memory (Magellan calls them "flight plans"), and to fly the routes either forward or backward. The SkyStar allows routes up to 20 legs in length (which is plenty); the GPS III Pilot allows routes up to 30 waypoints each. Since I fly mostly IFR and largely on airways, this is a feature that I use a great deal, and both units do a good job here.

The GPS III Pilot displays the active route on the route page that is one of the six nav pages in the unit's round-robin page sequence. The SkyStar requires that you bring up the route page via main menu selection, requiring more keystrokes. Once on the route page, both units provide a relatively easy-to-master route editor that permit creation and revision of stored routes.

Both models allow you to depart the pre-planned route and then rejoin it by going direct to a selected route fix (a common situation when flying IFR or making weather deviations). Neither model has a turn-anticipation feature that gives you advance warning of your new heading so that you can lead the turn (that would be a nice software enhancement).

Approaches

Neither the GPS III Pilot nor the SkyStar include instrument approach information in its Jeppesen database, and neither provides "approach monitor" capability the way the IIMorrow Precedus and GPSMAP-195 do. (We've heard rumors that the FAA frowns on manufacturers including such a feature in GPS receivers that are not approach-certified.) Neither unit provides the option of displaying runway centerline extensions to assist in lining up on approach (a useful and harmless-enough feature I'd like to see them add to the software).

Airport Information

Both models offer airport information such as field elevation, runway diagrams, runway lengths, and frequencies for ATIS, tower, ground, clearance, AWOS, UNICOM, and CTAF. Both do a good job here, although the GPS III Pilot has easier-to-read text displays and prettier airport diagrams which support zooming in and out.

Nearest Waypoint Search

Both models offer a comprehensive nearest waypoint search. In the SkyStar, this feature is activiated by pressing the NEAR key, and after a short delay displays lists of the 20 nearest:

• airports
• VORs
• NDBs
• intersections
• user-defined waypoints
• ARTCC (Center) frequencies
• FSS frequencies

The GPS III Pilot has a similar feature activated by pressing and holding the GOTO/NRST key. It displays lists of the nine nearest airports, VORs, NDBs, intersections and user-defined waypoints. It also displays the nearest ARTCC frequency, the nearest FSS frequency (one each), and up to three nearby special-use airspace areas (by name and controlling agency, but without comm frequency).

User-Defined Waypoints

Both models allow you to define and memorize up to 500 user-defined waypoints. The GPS III Pilot allows these waypoints to be defined in five different ways:

• Capturing ("marking") your present position
• Capturing the cursor position from the moving map
• Defined by a user-entered latitude/longitude
• Defined by a user-entered bearing and distance from another known waypoint
• Averaging your present position over a period of time

The last "averaging" method is intended to let you obtain a very accurate position fix when the receiver is stationary (presumably on the ground) by cancelling out the position errors created by GPS Selective Availability. It's probably more useful for hikers and surveyors than for pilots.

The SkyStar supports a similar set of capabilities for defining user waypoints, except that it does not support "averaging" (which is not especially useful for aviation use, anyway).

HSI Page

Both models include an "HSI" page that is useful for intercepting airways and radials, flying holding patterns, and providing backup guidance during instrument approaches. Both look precisely like a real horizontal situation indicator instrument, complete with compass rose, course arrow, lubber line, and rectilinear CDI needle. If you're used to flying a real HSI, you'll feel right at home.

But the GPS III Pilot page offers more functionality in several respects. You can manually rotate the course arrow (OBS) to any desired radial, while the SkyStar's OBS is hard-wired to the current route segment. And when VNAV is active, the GPS III Pilot displays a "glideslope" needle to show you graphically whether your GPS altitude is above or below the VNAV target altitude. (I find the pseudo-GS display convenient and intuitive, although some consider it dangerous since it suggests the precision of an ILS glideslope, yet is based on GPS altitude that can be in error by several hundred feet due to Selective Availability.)

Vertical Navigation

Both units provide vertical navigation to provide altitude guidance during letdowns, but they take quite different approaches. To use VNAV on the GPS III Pilot, you bring up a setup page and specify what altitude you want to descend to (generally pattern altitude or initial approach altitude), how far from the airport you want to reach that altitude (4 miles seems to be a good figure), and how rapidly you want to descend (I use 800 feet per minute). The Garmin monitors your GPS altitude (which is not terribly accurate, but is good enough for this purpose) and alerts you when it thinks you need to start down. You can then switch to the HSI page, on which a "glideslope" needle appears to guide you down.

The SkyStar's VNAV feature is tightly tied to its aircraft profile and flight plan facilities. To use it, you must have defined an aircraft profile with a non-zero descent rate. You must also be navigating on an active flight plan route. Under these conditions, a special "descent profile screen" appears in the nav page rotation that provides vertical guidance. As you approach the computed start-of-descent point, this screen shows you how much distance and time remains before you must start down. Once you pass that point, the screen shows your target altitude (which decreases as you approach your destination) and the rate-of-descent needed to get down in time.

Both VNAV schemes work well. The SkyStar is more automatic, the GPS III Pilot easier to set up, and I rather like the intuitive "glideslope needle" display; just don't be tempted to try flying precision approaches with it!

E6B Features

Both units include basic E6B features that have become de rigeur in handheld GPSs:

• True airspeed calculation
• Density altitude calculation
• Winds-aloft calculation

Unique SkyStar Features

A unique feature of the SkyStar (and one I'd like to see in every handheld GPS) is its ability to memorize aircraft profiles for up to five different aircraft, including:

• aircraft ID
• make and model
• climb rate, airspeed and fuel burn
• cruise airspeed and fuel burn
• descent rate, airspeed and fuel burn
• best glide airspeed and descent rate
• weight and balance envelope
• moment arms for various loading stations

Entering these profiles is a bit tedious (given the lack of a QWERTY keyboard), but you only have to do it once. Thereafter, you simply tell the SkyStar which aircraft you're flying (by selecting from a menu). Once you've done that, the SkyStar can perform calculations for you that no GPS has ever been able to do before.

Enter your flight plan route, and the SkyStar calculates your estimated time enroute and your estimated fuel burn for the trip, including climb and descent. Enter your actual fuel-on-board and the unit displays your estimated fuel quantity which counts down as you fly the trip. It also displays your estimated fuel remaining at your destination (so you can constantly keep track of how much "fuel cushion" you have as winds aloft change) and your estimated fuel remaining over any intermediate route waypoint (so you can easily evaluate alternates if a Plan B becomes necessary).

These time and fuel calculations have some limitations, especially if you fly a turbocharged or turbine-powered aircraft. It doesn't take into account the fact that such aircraft have vastly different cruise airspeeds and fuel burns at different cruising altitudes, nor that the cruising speed increases as fuel is burned off. But the calculations are adequate for most lightplanes, and the shortcomings could be corrected in subsequent software releases. Certainly Magellan has made a very good start at an important new capability.

Another nice feature for single-engine pilots is this: if you've selected an aircraft profile that includes best glide information, the SkyStar's nearest-airport search feature places an asterisk next to each airport that is theoretically within gliding range.

The SkyStar can also calculate weight-and-balance if you enter your fuel loading and weights of passengers and fuel at various load stations. This feature is probably of greatest interest to Part 135 operators who are required to do a formal W&B calculation for every flight and to write down the numbers on the flight manifest. But frankly, entering the W&B info into a handheld GPS is a tedious business; I think I'd be inclined to use a notebook computer and a good flight planning program like Destination Direct.

Another unique SkyStar feature is the ability to store up to five checklists, each containing up to ten items. The unit comes with five pre-defined checklists built in: emergency, pre-start, runup, pre-takeoff, and pre-landing. You can personalize these checklists with a checklist editor, then electronically "check off" the items in the cockpit.

Unique GPS III Pilot Features

The Garmin has several unusual features that reveal its origins as a unit adapted from one designed principally for automotive use: a trip computer and a highway nav page.

The trip computer provides a page that you can call up from the main menu. You reset it at the beginning of a trip, and it then calculates and displays two odometers, a trip timer, average trip speed, and maximum speed. (Fuel calculations would be really useful on this page, but unfortunately there are none.)

The highway page (in the nav page rotation) attempts to provide a three-dimensional perspective view in which your route appears as a highway (complete with black asphalt lanes and white centerline) and various fixes and airports appear as signposts. Frankly, I consider this page virtually useless for aviation use, and I wish Garmin had left it out of the Pilot model (or at least relgated it to some obscure menu rather than putting it right in the main nav page rotation). If you use the GPS to navigate during your drive home from the airport, I suppose you might find this page cute.

Like the GPS-90 and GPSMAP-195 before it, the GPS III Pilot also has a Garminesque feature called "Trac-Back" which lets you create an active route from the stored track history, allowing you to retrace your previous flight path in reverse. I'm sure somebody has found some use for this feature — perhaps CAP pilots flying search missions — but I just can't imagine ever using it myself.

GPS Receiver Performance

The GPS III Pilot has the same red-hot 12-channel parallel GPS engine used by the GPSMAP-195 and GPSCOM-190. It acquires a fix extremely rapidly after power up (typically in 15 seconds or less), and once acquired, it is extremely reluctant to lose lock. I torture tested the unit by intentionally trying sites with a restricted view of the sky and intentionally misorienting the antenna. Regardless of what I tried, the Garmin receiver performed spectacularly well.

Magellan's specification sheet does not specify how many parallel channels the SkyStar receiver supports. It cleverly refers to "Allview 12™" technology and says that it "tracks up to 12 satellites to compute and update position information." But watching it trying to acquire a position fix during difficult reception conditions, it appears the SkyStar uses a two-channel switching-type receiver. While capable of tracking all visible satellites, it cannot do so as quickly as a unit with 8 or 12 parallel channels. As a result, the SkyStar receiver takes three or four times as long to acquire a position fix than does the GPS III Pilot under identical conditions, and it seems to lose its fix somewhat more easily under adverse reception conditions.

Both units performed well in actual flight conditions, using a remote-mounted antenna suction-cupped to the windshield. (As mentioned earlier, the remote-mount antenna comes standard with the SkyStar but is an extra-cost option for the GPS III Pilot.) Even the slow 45 to 60 second initial lock-on time of the SkyStar is plenty fast to assure a good position fix by the time you've taxied out to the runup area.

GPS Initialization

When you first fire up either of the units out of the box, you're instructed to give the GPS receiver a rough idea of where it's located so it knows what satellites to look for and can acquire position reasonably quickly. You're supposed to do the same thing anytime the unit is relocated by more than about 300 miles while turned off. If you don't do this, the receivers can use a "cold start" procedure to figure out where they are, but this can take as much as 10 or 15 minutes.

Initializing the SkyStar is done by specifying either a nearby airport identifier or an approximate latitude and longitude. The GPS III Pilot uses a different approach: it displays a map of North America (or Europe or Asia if you're using one of the International databases) at an extremely wide scale. All you need to do is to slew a little arrow to the general vicinity of your present position, and the GPS has what it needs to perform a rapid acquisition of satellites.

Conclusions and Recommendations

When I first set about reviewing the GPS III Pilot and the SkyStar, I assumed since they both came on the scene at the same time and were priced identically ($799 list, $699 street price), they would be direct competitors. It quickly became apparent that this really isn't the case.

For one thing, the identical prices were an illusion because the Magellan's price includes all the usual accessories (yoke mount, remote antenna, cigarette lighter power cord, carrying case) while the Garmin's includes none of these. So the GPS III Pilot really cost $200 more than the SkyStar if we made an apples-to-apples comparison. Now that Magellan has dropped the SkyStar price by another $110, the difference between the two units is more than $300.

For another, the two units are fundamentally different in that the GPS III Pilot offers ground mapping capability and the SkyStar doesn't. This seems to me like such a fundamental difference that I think the two radios can be considered competitors only in the sense that you'd consider an automobile and a pickup truck to be competitors. Either you're looking for a ground mapping GPS or you aren't.

Garmin GPS III Pilot

To my way of thinking, the principal competition for the GPS III Pilot is its big brother, the GPSMAP-195. I've received dozens of e-notes from AVweb readers saying, "I was thinking about buying a Garmin -195 but I wonder if I should get the new GPS III Pilot instead and save some money?" That's certainly a valid question. Keep in mind, however, that the GPS III Pilot isn't $500 cheaper than the GPSMAP-195 — it's only $300 cheaper when you take into account the essential accessories that don't come standard with the GPS III Pilot. And for that $300 savings, you get a display with about half the resolution, a tiny keypad that's difficult to use in-flight, and no approach monitoring capability.

Given all that, I think I might be inclined to bite the bullet, spend the extra three hundred bucks and buy the GPSMAP-195. On the other hand, if $1,199 is more than your budget can tolerate, the $799 Lowrance AirMap 300 has to given serious consideration: it's $100 less than the GPS III Pilot (if you compare apples with apples), has a bigger display, a decent-sized keyboard, and does a credible job of ground mapping.

That's not to disparage the new Garmin. It's truly a remarkable unit which packages most of the capabilities of the superb GPSMAP-195 into a tiny package that's one-third the size. It has a red-hot GPS engine and a beautiful high-resolution display. But unless you truly need a unit that small, it seems to me that the GPS III Pilot's diminutive size is its greatest liability...particularly the small size of its keypad.

Magellan SkyStar

In my opinion, the SkyStar is the first really well-designed handheld that has come from Magellan. But exactly what is its market niche? It seems to me that the $589 SkyStar is a worthy successor to what is perhaps the best-selling handheld GPS of all time, the $549 Garmin GPS-90.

In that context, the SkyStar is a very attractive unit. It has more features and a bigger, higher-resolution display than the GPS-90. It offers a number of unique features not available on any other handheld (aircraft profiles, fuel calculations, W&B, checklists). Except for its lack of ground mapping capability, the few shortcomings of the SkyStar (like its awkward cursor/pan mode) are things that Magellan can readily fix in future software updates. All in all, it's a very attractive package.

On the other hand, for $210 more than the SkyStar, you could purchase a Lowrance AirMap 300 with twice the display resolution and good ground-mapping capability. You didn't really think it was going to be an easy choice, did you?

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Other AVweb product reviews that you may find useful in choosing which handheld GPS to buy:

• Three Ground Mapping GPS Handhelds
  (Airmap, Precedus, GPSMAP-195)
• Handheld GPS Roundup
  (survey of numerous handheld GPS models)
• Lowrance AirMap 300: What's New?
  (AirMap 300)
• Lowrance AirMap 100: Good Things Come in Small Packages
  (AirMap 100)
• Magellan GPS 315A: The First Under-$300 Aviation GPS
  (Magellan 315A)