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The Garmin GNS 530/430 combination is a common dual-GPS avionics suite for an IFR-certified airplane, costing around $20,000 plus a $500 per year subscription fee for Jeppesen database updates. A single 430 or 530 functions as a communications radio (COM), a VOR/ILS/GS receiver (NAV), and a moving-map GPS.
This review is based on 700 hours of usage in a 2002 Diamond DA40 and 300 hours of usage in a Cirrus SR20.
Let's start this review by considering the things that a pilot needs to know while in flight. We'll then go through these items and see how the information can be obtained from the Garmin GNS 530/430 combination. Here's a partial list:
[The Garmin does have one extra feature that might be useful if you had to take over the controls and flight planning over unfamiliar terrain at night from a pilot who had collapsed: MSA. You can configure the unit to show "minimum safe altitude" pulled from the Jeppesen database. In flying over Kansas this turned out to be very close to what the paper IFR chart said. In flying over New Mexico the MSA displayed by the Garmin was 2000' higher than the paper chart's recommendation and more than 4000' higher than the plateau over which the airplane was traveling. On balance it is about as useful as telling someone "if you fly above 20,000' MSL you won't hit anything between San Francisco and New York."]
Because there is no way of entering an airway into a flight plan, the Garmins cannot display information on minimum enroute altitudes (MEAs) or minimum obstacle clearance altitudes (MOCAs). Suppose that you're picking up a bit of ice in the clouds. You recall from an earlier weather briefing that the freezing level was 8000 feet. You'd like to know how low you can go, legally and safely, on this airway before calling ATC. You'll need to refer to the paper charts.
[Note that you could accomplish this via the Garmin's text Nearest Airport page but it would be nearly as many keystrokes, nearly as much reliance on positioning the cursor, and you have to figure out for yourself how the airports listed on the Nearest page relate to the little symbols that you've seen on the moving map.]
This warning motivates you to tune Missoula Tower on the GNS 530 COM side. You're talking with ATC and the MSG lights begin flashing again. You press the MSG button and learn "Airspace 2 minutes ahead". You press the MSG button a second time to restore the navigation display. The tower has cleared you to land and you're busy getting the airplane set up for a straight-in approach. While on final, the annunciator panel and the Garmin are flashing again. Two more presses of the MSG button and you learn that you're "Inside Airspace".
Was this distraction necessary? Consider that the communications radio and the airspace warning system are inside the same physical box. The GNS 530 has seen you select the tower frequency from a menu of frequencies for the Missoula airport. The GNS 530 has seen you key the microphone and transmit on that frequency. Can it not infer that you've figured out that this is controlled airspace and suppress additional warnings?
Taking off from a Class D airport the experience is similar. The Garmin watches you select ATIS, Ground, and Tower frequencies. The Garmin watches you transmit and receive on Ground and Tower. You're climbing out, carefully monitoring your gauges because you know that this is the riskiest phase of flight for engine failure and other mechanical problems. The annuniciator panel begins flashing. You panic a bit and then realize it is only the MSG light. You press the MSG button on the GNS 530 and learn that you're "Inside Airspace."
Flying through Class C or Class B airspace typically sets off 10 to 15 warnings from the GNS 530. You're already inside the Charlie and yet the Garmin is screaming "Airspace near and ahead". One possible explanation for this phenomenon is that Garmin's programmers have modelled each section of a Charlie or Bravo as a separate chunk of airspace. Thus as far as the Garmin is concerned when you go from the outer ring of a Charlie to the inner ring it is just the same as if you went from a military operating area into a Class D.
There is no way to tone down the airspace warnings from the Garmin. With some cursor gymnastics, you can turn off warnings for different classes of airspace. If you're going to be flying IFR, for example, you can turn them all off with about 25 keystrokes. But if you want any warning at all about a Class C you've got to accept 15 warnings about each Class C through which you transition. If Garmin can't make its software smart enough to link up the pieces of a Class C, it would be nice to have a menu option to "mute airspace warnings for 15 minutes" from the message screen. But pressing the Menu button while a warning is being displayed reveals no options at all. I mentioned this possible enhancement to a Garmin field rep and he stared back blankly.
The GNS 430 lacks all of these features.
"The pilot was in the process of selecting the approach in the airplane's global positioning satellite (GPS) receiver [GNS 430], when he noticed that the turn coordinator was "pegged to the left, with no flag," and that the airplane was losing altitude rapidly. The pilot disengaged the autopilot and attempted to stabilize the airplane."A regional jet pilot spent 100 hours flying with the Garmin 430/530, read every page of the user's manual, watched the training video, and concluded that "The capabilities of the units can be impressive but they are way too hard to use; in our $20 million jet you're set if you know how to read English and push buttons."
One reason the Garmins are so hard to use is that they don't have soft keys. Suppose, for example, that a screen in your airplane is displaying a list of frequencies for an airport. You can see the frequency that you want right in front of you. If voice recognition systems were more reliable it might be best simply to speak to the airplane: "tune ATIS". If you had a touch screen and clean fingers it would be easy to touch the ATIS frequency. But what most of the good avionics interfaces do is provide a line of buttons next to the lines on the display. If you push the button next to the ATIS frequency, you've tuned ATIS. This button doesn't have a label on it because on a different screen it would have a different function. That's what makes it a "soft" key. The true multifunction displays such as the Avidyne and the Garmin/Apollo MX20 all rely on soft keys, as do some car stereos (the LCD labels above the buttons change depending on whether you're listening to radio, cassette, or CD).
Much of the hysteria surrounding airspace and other messages from the Garmins could be eliminated if they rolled the message through the text area in the lower right corner of the screen. Most of the messages are very short and there is no reason to ask the pilot to take his or her hands from the flight controls to press the MSG button twice.
Better integration among the Garmin components would help. For example, suppose that you want to listen to a weather report broadcast on a VOR. You tune NAV1 to the correct frequency. You press NAV1 on the Garmin GMA 340 audio panel. You can't hear the weather. You fiddle with the NAV1 volume control. You still can't hear the weather. Then you remember that you have to take your eyes away from the instruments and traffic for a moment to see if a little "ID" symbol is lit in the NAV1 data block. If isn't. So you press the NAV1 volume control knob in to engage "ID mode" on the GNS 530. Given that both the audio panel and the navigation radio were both made by the same company, why wasn't the navigation radio smart enough to switch itself into ID mode as soon as the pilot indicated a desire to hear what was on the nav radio (by pushing the button on the audio panel).
A Cirrus owner comments:
"I am very disappointed with the Garmin 430 pair in my SR20. The Avidyne gives you a more detailed moving map but the combo is nowhere near what the Apollo MX20 does (actual charts). The Garmin/Avidyne combo has no vertical information (i.e MEA's, approach heights, etc.) so you have to have paper charts for everything.My personal conclusion is that the Garmins are, by and large, unsafe for single-pilot operation. It may be possible to use some of the unit's sophisticated capabilities if you program everything in advance on the ground but if things change in-flight you must always be prepared to revert to basic moving-map and paper charts.
"When you tell other pilots that the Garmins suck they usually say 'Oh, that's because you haven't used them enough; once you learn them you'll love them.' But these are mostly guys who've only flown older airplanes with primitive Nav/Coms. People who have some experience designing user interfaces are appalled."
Most older standalone NAV radios have squelch that a pilot can adjust in flight and this would be a welcome improvement for the Garmins, at least in a noisy electrical environment such as the Diamond Star DA40.
A useful feature of the GNS 530 is the ability to establish user-defined warnings. For example, you can have the Garmin give you a "switch fuel tanks" warning every 30 minutes.
When you're out on a long cross-country it can be fun to look at the GNS 530's odometer page, which shows the total number of nautical miles traveled since the 530 was installed (there is also a resettable trip odometer).
What if your destination airport lacks an ILS? Twist the OBS on your HSI to the runway heading, e.g., 290 if you're landing on 29. Push the "OBS" button on the Garmin. The GPS moving map will now display a big extended runway centerline while your HSI will show you graphically how far you are from that centerline.
You can bring up KBED in the Waypoint pages but none of them will give you the bearing to the waypoint. You won't find KBED in the Nearest pages because it is too far away. The solution is to tell the Garmins that you want to go direct to Bedford but abort the procedure at the last step: press the direct button, dial in KBED using the cursor wheels, but press the clear button instead of enter when prompted for the final activation. The last screen that you see should give you the distance and heading to Bedford, thus enabling you to evaluate whether or not your current clearance is getting you anywhere near your goal.
Here are a couple of useful tips I got from a very good CFII
- When selecting an approach, never choose "vectors for final". Choose the IAF which makes the most sense from your position. Even if ATC will give you vectors, they may at any time choose to say "go direct PLASM" or something, and if you don't have the full approach, you will be one busy knob twister. If you actually do get nothing but vectors to final, simply activating the final leg of the approach is good enough.
- After entering a flight plan, always zoom out and look for "spikes". These are misspellt intersections. Much better to find out now than later, when the autopilot decides to make a 90 degree turn into the mountains.
- If you fly certain routes often, save a flight plan with all the usual alternate routes programmed in. It is far easier to delete existing entries as ATC gives you your next routing than to twist in new waypoints.
- Get used to using "direct enter enter" and "menu enter enter" without looking at the screen.
Did you know about this bizarre behaviour where the GNS430 will deactivate the approach if you're even just a little off of the FAF? The natural reaction of most people is to "reactivate the approach", which will send you back to the IAF - not a good idea when on autopilot with 500feet/min descent rate dialed in...
-- Christian Goetze, April 10, 2006
For finding the nearest approach or departure controller, it requires a few (many) more key presses knob twisting, but here's a way you can do it: Go to the nearest airport page, and pick the nearest airport. Bring up that airport's frequency page, and find its departure or approach frequency. This is more often than not the proper apch/dep controller for the area, or someone who can hand you off correctly.
-- Joshua Levinson, February 17, 2009
I just came across your review of the Garmin 530/430. I have to say that I think your view of the GNS530 being "nearly impossible to learn" and "unsafe" is a bit off the mark.
I fly the Boeing 747-400 and I find the system logic to be very similar to the Boeing and very user friendly. These units are designed for IFR flying. They do have a few things that are missing like airways and altitudes but they are very good in the IFR environment. If you just have the basic understanding that you can only navigate to a point and not from a point you are halfway there. Remember that these units are over 10 years old now. There was no such thing as an iPad or touch screens 10 years ago. They don't do everything for you but they do what you need very well.
-- Lance M, November 28, 2011