First impressions: flying the Avidyne IFD540

cShort version: The transplant was a success and the patient made it home.

Now, the longer version.

I originally dropped the plane off on 31 December at Sarasota Avionics at Tampa Executive (KVDF). The plan was to have the plane ready by late January. That didn’t happen. When I went to pick the plane up on February 10th, it wasn’t ready as promised: the GPS steering steered the plane in the opposite direction as commanded, the interconnection between the new GPS and our engine monitor didn’t work, and the plane failed its initial FAA ADS-B Out automated compliance report (ACR) check. I was really unhappy, flew back to Huntsville, and started firing off emails to get the problem fixed. Long story short, Kirk Fryar, the co-owner of Sarasota, moved the plane to their Venice location, fixed everything that was wrong, tested the plane thoroughly, and had it ready for me on the 25th. (I note with some irritation that I still haven’t ever had an experience with any aircraft maintenance shop that resulted in the plane being ready when it was promised.)

I met Leonard, Sarasota’s check pilot and flight instructor, at KVDF and we flew the plane down to KVNC, stopping along the way to hand-fly the ILS 32 at KSRQ. It was a windy, bumpy day and ATC was vectoring me all over the place (including nearly to the Gulf ADIZ). I was a little rusty, and it showed. Another thing that showed: the localizer flag on the NAV1 CDI (we’ll call this squawk #1). This little flag is supposed to pop out to indicate that the associated signal is unreliable. It’s definitely not supposed to appear in a brand-new avionics installation, especially not when my secondary nav radio didn’t show the flag. We flew a missed approach and then took the RNAV 5 approach into KVNC. This time I let the autopilot and GPSS fly the approach, which it did flawlessly.

While I barricaded myself in their conference room to get some work done, Kirk investigated the cause of the localizer flag problem. It turned out to be simple, stupid, and Avidyne’s fault. There’s a known compatibility issue between early hardware revisions of the IFD540 and the King KI209A CDI we have. Sarasota sent our original unit back to Avidyne to have the hardware modification installed– we needed mod 14 but, for some unknown reason, we got a unit back that only had mod 11. This means that we have to take the plane back to the shop to swap in the new IFD540 unit when it arrives, which is a hassle… but more on that later.

After a thorough preflight, during which I confirmed that the fuel flow data presented to the IFD540 was intermittent (and that’s squawk #2, but not a huge deal since there’s a workaround: power-cycle both the CGR30P and the IFD540), I took off and picked up my clearance to Grady County. They gave me a route out over the water: direct TABIR, then direct 70J. I plugged it in, climbed out, and engaged GPSS. It flew smoothly to TABIR. There’s a lot going on in the picture below:

• The magenta line is where I’m going. Note that at the TABIR intersection, the onward path changes to a “candy cane” stripe to indicate the next planned leg. Other legs further on show up as white. This makes it easy to see what the box is planning on doing at all times.
• The little blue diamonds are other airplanes, with their relative altitude shown and little up or down arrows indicating climbs or descents. The inner dashed ring has a 5nm radius, so I can clearly see where interesting targets are and what they’re doing.
• The blue flags indicate VMC at those reporting points. this is a bit of a change from Foreflight, which uses little green dots for VMC METARs. However, the FAA specifies the exact symbology and colors that have to be used in certified devices so we’re stuck with those.
• Just above the “FMS” button you can see a tiny label that says “Rgnl Rdr 9 Min”. That means I have relatively fresh radar data on screen; however, since the sky was completely cloudless when I took the picture, there’s nothing shown.
• The radio at the bottom of the stack “knows” that 119.275 is the AWOS frequency for Venice. Why? The GNC255 has an onboard frequency database, and now that Sarasota connected it to a GPS position source, it can look up the frequency and aircraft position and use that combination to label who you’re talking to.

There was a stiff (25+kt) headwind and I was burning fuel faster than I liked, so I decided instead to stop at 40J. I landed, took on 62 gallons (meaning I had 20gals left, or a little over an hour’s flying time, in reserve) and set out for home. Along the way, I customized the datablock display– one of the big features of the IFD540 is that you can extensively customize what data is displayed and where it appears, then save that configuration in your own profile. That way Derek and I can each set up things the way we like, then load our own profiles on demand. Here’s what I came up with:

• The left side top shows me the current communications and navigation frequencies I have tuned. Note that the unit automatically labels the frequency as soon as you tune it. (Not shown is the extremely useful FREQ button, which, when pushed, shows you a list of the frequencies you are most likely to need based on your location and phase of flight).
• Below the frequency datablocks, I see my destination, distance, and estimated time enroute. I will see fuel remaining on arrival once the fuel flow issue is fixed.
• The top line shows the current ETA to my destination, my groundspeed, and the current navigation mode. It says “GPS” in this picture, but it could also show other labels depending on whether I have an approach loaded, the type of approach, etc.
• The right side shows, in order, the destination and distance (which I’ll probably remove), the bearing and distance to the nearest airport, and the track, distance, fuel remaining, and ETE for the next waypoint (that info is shown in magenta, indicating that it’s tied to the current waypoint). Because I am going direct to my destination, this magenta block is the same as the destination data on the left. (You can also see the minimum safe altitude and flight timer, right over the traffic display thumbnail).

On the way home, I decided to do a couple of turns in the hold at the ATHEN intersection. This is normally part of the RNAV 36 approach to Decatur; I didn’t want to fly the whole procedure, but I wanted to see how the IFD540 handled a hold at an arbitrary waypoint. Turns out it’s just about as simple as you can imagine: you pick the waypoint (any one will do: airport, intersection, VOR, whatever), tell the box you want to fly a hold, and then watch it do its stuff. When you want to exit the hold, you sequence the next waypoint as direct and the magic happens. Thanks to GPSS, the plane happily flew the entire hold on its own, including compensating for the winds.

One more squawk: the IFD540 and the other devices are super-bright in their default night modes. I think the dimmer settings are wrong, because the panel light rheostat that controls all the other lighting (including the CGR30p) did nothing to change the brightness of the IFD540, so I had to manually adjust it. All of these squawks will be addressed when we take the plane back to Sarasota’s shop, this time the one in Tullahoma, just a short flight from here. It shouldn’t take more than 15 minutes or so to swap out the IFD540; fixing the other issues might take a bit longer.

First impressions of using the IFD540 for a cross-country IFR flight:

• I am very impressed with the display brightness and clarity and the overall build quality of the switches and knobs on all of the hardware.  Being able to switch between items using the left/right rocker switches (labeled “FMS”, “MAP’, and “AUX”) is easy and intuitive. Touch response is fast, and multitouch for panning and zooming worked flawlessly.
• The UI is responsive and the graphics are clear and readable. The screen seems huge compared to my old KLN94.
• By default, the combination of land and navigation data presented on the map is cluttered, but it’s easy to declutter.
• Avidyne brags about their “hybrid touch” interface, in which nearly every action can either be performed directly on the touch screen or by using the knobs and buttons. That  flexibility works very well and was most welcome during my bumpy flight home– aiming precisely at a touchscreen in moderate turbulence can be a challenge.
• Once you get used to the notion that there are sliding tabs (like the “DATA” tab visible next to the “minimum safe altitude” field in the picture above), it becomes very easy to flip between sets of data, such as the flight plan view when in FMS mode.
• The location awareness features of the IFD540 are a real time saver. The FREQ button knows what frequencies to present based on where you are, the unit can automatically tune (and ID) the next VOR in your flight path, and so on.
• Speaking of FMS: flight plan entry, approach management, and so on use a metaphor that’s close to, but still different from, the King/Garmin-style interface that most pilots are used to. It’s like the difference between Brazilian Portuguese and Portuguese Portuguese: lots of common vocabulay and idiom, but some very important differences. I’ll have more to say about that once I have more time flying with it and learning the FMS way of doing things. (It’s interesting that Bendix King, whose KSN770 competes with the IFD540, has the same issue in that the KSN77o steals a lot of FMS-style behavior from BK’s jet FMS family.)
• The top-of-descent (TOD) marker is a really nifty feature; it tells you where to start your descent in order to hit an altitude constraint on the flight path. The audio cue, along with the audio cue for 500′ AGL, are very valuable prompts. I’d love to see Avidyne add an audio prompt indicating when you reached the missed approach point (MAP) for approaches that define them.
• I think, but have not confirmed, that the IFD540 should be able to drive the STEC PSS so that the autopilot  can follow an LPV-generated glideslope. It will take a little knobology for me to figure out how to set this up, though.
• There are many things I learned to coax the KLN94 into doing that I don’t yet know how to do on the IFD540, so this learning process will take a little while. On the other hand, there are many, many things that the IFD540 can do that the KLN94 and Garmin GNS-x30 series can’t.

What about the rest of the stack? Well, the transponder just works… not much to say there. It transmits ADS-B Out like it’s supposed to, so I’m delighted. The AMX240 audio panel is a huge improvement in audio quality and functionality over the old KMA20 we had before. I’ll have more to say about those gadgets, and the GDC-31 roll steering converter, in the future. Overall, I’m delighted with the new stack and can’t wait to fly it a bunch more!