Choosing an IFR GPS navigator

[henryhallam]

In my Lancair 360 I've been using a Skyview Classic SV-D1000 + SV-D700 + GNS-480 and have been quite happy with them. I just bought a Lancair IV-PT and its avionics are obsolete and unsupported (Chelton IDU-III EFIS + GNS-530W + GNS-430). Time for a whole new panel I think, Skyview HDX of course, but it means picking a GPS navigator or nav/com.

I've briefly used the Garmin 650 on a couple of other aircraft and hated it. Does it grow on you? Is the 750 much better? How about the new Xi models?

I've used the Avidyne IFD440/540/550 series even less, but liked them more, and from reading about them the UI philosophy is more my style. The FMS features and the bluetooth keyboard are very appealing. How well do these integrate with the Dynon ecosystem?

Considering a few options. All would have an SV-HDX1110 PFD on pilot and copilot side, SV-AP-PANEL and SV-KNOB-PANEL somewhere central, SV-GPS-2020 and SV-ADSB-472 remote-mounted. I currently have a GTX-330ES transponder, might keep it or might replace it with SV-XPNDR-261 depending on how full the panel looks. Engine monitoring for the turbine would primarily be through the Skyview, but I have a small instrument from VR Avionics that displays the most important parameters that I'd keep as a backup.

Some possibilities:
1. A third HDX display, either 7 or 10 inch, in the center as MFD and backup PFD, IFD440 underneath or above as GPS/nav/comm, SV-COM-X25 as secondary comm.
2. As above but with GNS650 or GNS335 in place of the IFD440.
3. No third HDX, but IFD550 at prime position in the center stack acting as GPS/nav/comm/MFD and as a PFD backup with its built-in AHRS.
4. Dynon comes out with an IFR GPS capability and there is much rejoicing.

Capability and redundancy goals:
- This plane is flown IFR the vast majority of the time (though usually in VMC) since it has to be in the flight levels, so a strong IFR user interface is a must.
- Prefer not to rely on the copilot-side HDX either as an MFD or backup PFD - view angles aren't great.
- OK with single, non-redundant VHF nav, or maybe no VHF nav at all. I want to rip those antennas off anyway.
- OK with single IFR GPS, I think. Certainly OK with that from a safety of flight point of view, but maybe it's bad for dispatch reliability.
- Dual VHF comm is required, but OK for only one comm to support 8.33 kHz.
- Having once had an unfortunate wiring short in my 360 that took out both ADAHRS in IMC (despite notionally independent and redundant wiring), some kind of dissimilar redundancy for the PFD is appealing. But I could satisfy that with one of the various $1-2k 3.25" standalone backup PFD/EFIS things.

Interested in any thoughts.

 

[WmInce]

Just out of curiosity . . . why did you hate the G-650?

 

[henryhallam]

Too much reliance on touch, inefficient flashy UI - e.g. the menu uses huge icons & buttons, vs neat smaller text labels that I'm used to from the 480. I expect that's partly because they need to give you a large target to reliably mash with your finger in turbulence. But even outside of the menus, it seems to me that the 480 conveys as much or more information with less than half the pixels

Admittedly I only have a couple of hours with the 650, and I'm sure the 750 does a better job with more real estate. But with only one knob it's still heavily reliant on touch. Touch is great on the ground and in the flight levels, but it's a real distraction during bumpier periods on departure and arrival, where the workload is also highest.

 

[Carl_Froehlich]

I used the GTN-650 on the last two projects - only because it is the least bad of all the bad options. Compared to the intuitive nature of the SkyView, the GTN-650 is very clunky.

For the new project I will probably go with the Garmin GNC-355 (same as the GTN-650 but no VOR/LOC/GS). I find I’m only using ILS for practice approaches, not real ones.

The larger screen 750 is, in my opinion, a waste of money. The screen is far less useful than what you already have displayed on the SkyView.

Now if only Dynon will come out with a TSO GPS navigator we would have a perfect world…..

Carl

 

[jsalak]

I like the Skyview system with an IFD540 and Foreflight for IFR capability in my RV. Coupled AP capability for approaches is nice. Plan flights off-aircraft with ForeFlight and upload the FP to the panel when you get to the aircraft (Skyview WiFi).

I would think something like dual HDX1110s, ADAHRS, XPNDR-261, ADS-B-272, GPS-2020, SV-ARINC, AP-Panel, Knob-Panel, SV-COMM (#2 comm), and SV-WiFi with the IFD550 would be a nicely integrated package. Maybe a D3 for backup. An iPAD with Foreflight and the IFD100 apps allow a lot of interface flexibility. The IFD100 app basically turns your iPAD into a second IFD5xx display you can use to control the real IFD5xx. The iPAD IFD-xxx Trainer app is also nice for training.

JS

 

[RV6-KPTW]

JS - you described my panel. I like the setup and am so impressed with the IFD540. It really simplifies IFR. I used G430 for 15 years or so and that worked great but occasionally the route planning effort and entry was pretty high. I have a D2 as a backup but am considering switching to Sentry and Foreflight.

 

[skysailor]

Sadly, moving away from the GNS 480, everything is a compromise. Mine is paired with a Skyview in the Glasair Super IIS RG I just put up for sale. What a great combination! One night on a trip to the northeast I was given three full route clearances in the space of ten minutes all different from the filed route I was on at the time. Without the 480 it would have required vectors while consulting charts and typing. With the 480 it was not even an issue. Great IFR navigator. Works seamlessly with the Skyview.

 

[airguy]

I like the Skyview system with an IFD540 and Foreflight for IFR capability in my RV. Coupled AP capability for approaches is nice. Plan flights off-aircraft with ForeFlight and upload the FP to the panel when you get to the aircraft (Skyview WiFi).

I would think something like dual HDX1110s, ADAHRS, XPNDR-261, ADS-B-272, GPS-2020, SV-ARINC, AP-Panel, Knob-Panel, SV-COMM (#2 comm), and SV-WiFi with the IFD550 would be a nicely integrated package. Maybe a D3 for backup. An iPAD with Foreflight and the IFD100 apps allow a lot of interface flexibility. The IFD100 app basically turns your iPAD into a second IFD5xx display you can use to control the real IFD5xx. The iPAD IFD-xxx Trainer app is also nice for training.

JS

That's what I'm running, with the exception of IFD440 instead of the 540. With the large HDX screens the only thing I use the screen on the 440 for is programming the route. No need to buy more square inches of expensive glass.

 

[jsalak]

JS - you described my panel. I like the setup and am so impressed with the IFD540. It really simplifies IFR. I used G430 for 15 years or so and that worked great but occasionally the route planning effort and entry was pretty high. I have a D2 as a backup but am considering switching to Sentry and Foreflight.

I just added a Stratux receiver to play around with and to see how it works as a backup GPS/ADS-B/ADAHRS with Foreflight. I had thought about the Stratus 3, however it costs as much as the D3, so the Stratux is an inexpensive experiment. I was already running a Dual WAAS GPS with the Foreflight app, I think four GPS sources is enough for the moment.

 

[kp_airdallas]

In my Lancair 360 I've been using a Skyview Classic SV-D1000 + SV-D700 + GNS-480 and have been quite happy with them. I just bought a Lancair IV-PT and its avionics are obsolete and unsupported (Chelton IDU-III EFIS + GNS-530W + GNS-430). Time for a whole new panel I think, Skyview HDX of course, but it means picking a GPS navigator or nav/com.

I've briefly used the Garmin 650 on a couple of other aircraft and hated it. Does it grow on you? Is the 750 much better? How about the new Xi models?

I've used the Avidyne IFD440/540/550 series even less, but liked them more, and from reading about them the UI philosophy is more my style. The FMS features and the bluetooth keyboard are very appealing. How well do these integrate with the Dynon ecosystem?

Considering a few options. All would have an SV-HDX1110 PFD on pilot and copilot side, SV-AP-PANEL and SV-KNOB-PANEL somewhere central, SV-GPS-2020 and SV-ADSB-472 remote-mounted. I currently have a GTX-330ES transponder, might keep it or might replace it with SV-XPNDR-261 depending on how full the panel looks. Engine monitoring for the turbine would primarily be through the Skyview, but I have a small instrument from VR Avionics that displays the most important parameters that I'd keep as a backup.

Some possibilities:
1. A third HDX display, either 7 or 10 inch, in the center as MFD and backup PFD, IFD440 underneath or above as GPS/nav/comm, SV-COM-X25 as secondary comm.
2. As above but with GNS650 or GNS335 in place of the IFD440.
3. No third HDX, but IFD550 at prime position in the center stack acting as GPS/nav/comm/MFD and as a PFD backup with its built-in AHRS.
4. Dynon comes out with an IFR GPS capability and there is much rejoicing.

Capability and redundancy goals:
- This plane is flown IFR the vast majority of the time (though usually in VMC) since it has to be in the flight levels, so a strong IFR user interface is a must.
- Prefer not to rely on the copilot-side HDX either as an MFD or backup PFD - view angles aren't great.
- OK with single, non-redundant VHF nav, or maybe no VHF nav at all. I want to rip those antennas off anyway.
- OK with single IFR GPS, I think. Certainly OK with that from a safety of flight point of view, but maybe it's bad for dispatch reliability.
- Dual VHF comm is required, but OK for only one comm to support 8.33 kHz.
- Having once had an unfortunate wiring short in my 360 that took out both ADAHRS in IMC (despite notionally independent and redundant wiring), some kind of dissimilar redundancy for the PFD is appealing. But I could satisfy that with one of the various $1-2k 3.25" standalone backup PFD/EFIS things.

Interested in any thoughts.

Option no. 3 sounds good.
3. No third HDX, but IFD550 at prime position in the center stack acting as GPS/nav/comm/MFD and as a PFD backup with its built-in AHRS.

but IFD550 has only built-in ARS module. (Attitude Reference System - only Pitch and Roll)
- I would say, the best way to go is install Dual SV-ADAHRS-200. Second one for Redundancy.

This would be perfect option for you.

- Pilot and Co-pilot HDX 10"
- Dynon Engine Monitoring thought Skyview
- IFD550 with ARS Module or IFD540
- PAR200B with Secondary COMM. supports both 25KHz and 8.33 KHz by click of a button.
- SV-AP-PANEL
- SV-KNOB-PANEL
- Garmin G5 with AHRS as a secondary EFIS

Email me at kp@airdallas.com if you need a quote.

Thank you,
KP

 

[Bill Putney]

That's what I'm running, with the exception of IFD440 instead of the 540. With the large HDX screens the only thing I use the screen on the 440 for is programming the route. No need to buy more square inches of expensive glass.

Can you provide wiring tips for the 440 to HDX using the AV-ARINC? Does all the GPS and NAV go through the ARINC? I presume there is no NAV or COM frequency channeling from the HDX to the 440?

Thanks,
Bill

 

[airguy]

Can you provide wiring tips for the 440 to HDX using the AV-ARINC? Does all the GPS and NAV go through the ARINC? I presume there is no NAV or COM frequency channeling from the HDX to the 440?

Thanks,
Bill

The Dynon installation manual has excellent wiring advice in there for the Dynon ARINC to the Garmin 430W, and the Avidyne IFD440 uses exactly the same pinout and tray as the Garmin 430W.

I started with a 430W and then about a year ago upgraded to the IFD440. I literally powered up the 430, recorded all the setting and parameters, shut it down and pulled it out, shoved in the IFD 440 and powered it up, entered the settings I had pulled from the 430W, and it worked. 20 minutes total, no muss no fuss.

 

[Bill Putney]

The Dynon installation manual has excellent wiring advice in there for the Dynon ARINC to the Garmin 430W, and the Avidyne IFD440 uses exactly the same pinout and tray as the Garmin 430W.

I started with a 430W and then about a year ago upgraded to the IFD440. I literally powered up the 430, recorded all the setting and parameters, shut it down and pulled it out, shoved in the IFD 440 and powered it up, entered the settings I had pulled from the 430W, and it worked. 20 minutes total, no muss no fuss.

Of course! Duh... I forgot about the G430W slide in replacement. How does it behave over ARINC. Do you get all the VOR-LOC-GS info over ARINC?

 

[airguy]

Of course! Duh... I forgot about the G430W slide in replacement. How does it behave over ARINC. Do you get all the VOR-LOC-GS info over ARINC?

Sure do - it all shows up on the Dynon HSI once you have the 430W/IFD440 properly configured, for either VHF or GPS approaches. You can hand fly it or couple to the autopilot.

 

[Bill Putney]

Thanks!

 

[czfish]

Sure do - it all shows up on the Dynon HSI once you have the 430W/IFD440 properly configured, for either VHF or GPS approaches. You can hand fly it or couple to the autopilot.

I'm doing a new IFD540 install (not a slide in replace for Garmin) but trying to get the ARINC setup to work into SV HDX. The SV Install manual ARINC settings don't look like the settings I see for ARINC in Setup Mode. What ARINC settings are needed from SV side and from IFD side to get ARINC to handle pushing all the VHF or GPS flight plan and HSI information? I assume once they are talking well at this level, my SV autopilot will just dovetail in to what ever the navigation source is. Help needed. Thanks.

 

[CanardMulti]

The wiring schematics for 530 / 430 will work for the IFD540 / 440, but the IFD units can do more if you add a couple of pins to the harness. Specifically, you can get aural warnings, monitoring of standby frequencies, and various indicator lights. Also, while the IFD550 is a great unit, it costs more than an IFD540 + an EXP version of the Garmin G5, with the added bonus that the G5 adds pitot static data that the 550 cannot provide.

The GPS steering information generated by the 540 / 440 that gets sent to SkyView over ARINC via the SV-ARINC-429 can be duplicated on the G5 via one of the IFD's RS232 ports. Result is that if for whatever reason both your SkyView screens go dark (Mr. Murphy is alive and well after all) you can keep right side up, on speed and altitude, w/ G5 AND fly whatever flight plan is loaded in your IFD.

For actual IFR, I'd consider dual ADAHRS a must. The system will flag you if the two ADAHRS disagree and ask you pick which one to believe. The G5 becomes the tie breaker.

Ken

 

[Marc_J._Zeitlin]

For actual IFR, I'd consider dual ADAHRS a must. The system will flag you if the two ADAHRS disagree and ask you pick which one to believe. The G5 becomes the tie breaker.

Kind of OT here, but I have such a setup - dual HDX, dual ADAHRS, and a G5.

The statement "The system will flag you if the two ADAHRS disagree" is sort of true - there is a threshold above which they must disagree before it will throw an error message and flag you. I didn't realize this, and had an ADAHRS mismatch of about 8 - 9 degrees in roll, with NO error shown whatsoever. I felt this was unacceptable. After getting the primary ADAHRS repaired, discussions with the Dynon techs eventually turned up the fact that there's a threshold, with a default of 10 degrees for roll (and I don't remember the threshold for yaw or pitch, or a host of other parameters). 10 degrees of roll mismatch seemed like a crapload to me, so I've dialed it back to 8 degrees (it's settable in the config file) and we'll see if I ever get a false mismatch error. If not, it'll get dialed down lower.

Sorry for the OT rant, but your statement is not quite complete. Other than that, I agree with you completely.

 

[CanardMulti]

Kind of OT here, but I have such a setup - dual HDX, dual ADAHRS, and a G5.

The statement "The system will flag you if the two ADAHRS disagree" is sort of true - there is a threshold above which they must disagree before it will throw an error message and flag you. I didn't realize this, and had an ADAHRS mismatch of about 8 - 9 degrees in roll, with NO error shown whatsoever. I felt this was unacceptable. After getting the primary ADAHRS repaired, discussions with the Dynon techs eventually turned up the fact that there's a threshold, with a default of 10 degrees for roll (and I don't remember the threshold for yaw or pitch, or a host of other parameters). 10 degrees of roll mismatch seemed like a crapload to me, so I've dialed it back to 8 degrees (it's settable in the config file) and we'll see if I ever get a false mismatch error. If not, it'll get dialed down lower.

Sorry for the OT rant, but your statement is not quite complete. Other than that, I agree with you completely.

Thanks for the info. I wasn't aware of the thresholds, let alone that they could be tweaked. If they're in the install or ops manuals, they are very well hidden. Very good to know. Both of my ADAHRS are under rear left pax seat and the internal magnetometers are used (no remotes). The two times I've gotten the disagree message in flight, I'd inadvertently stored my towbar too close to them. It gets stored elsewhere now.

Ken

 

[Marc_J._Zeitlin]

Thanks for the info. I wasn't aware of the thresholds, let alone that they could be tweaked. If they're in the install or ops manuals, they are very well hidden. Very good to know.

Not in the manual, AFAICT. Here are the relevant parameters from the USER_CONFIG file (version 15.4.7 - don't know if version 16 is different):

adahrs_xchk_enabled=1​

adahrs_xchk_attrecvr_settle_time=128​

adahrs_xchk_iasalive_thres=30​

adahrs_xchk_iasalive_settle_time=128​

adahrs_xchk_pitch_flt_shift=8​

adahrs_xchk_roll_flt_shift=8​

adahrs_xchk_hdg_flt_shift=8​

adahrs_xchk_gmeter_flt_shift=8​

adahrs_xchk_tc_flt_shift=8​

adahrs_xchk_tr_flt_shift=8​

adahrs_xchk_ias_flt_shift=8​

adahrs_xchk_alt_warmup_time=4800​

adahrs_xchk_alt_flt_shift=8​

adahrs_xchk_aoa_flt_shift=8​

adahrs_xchk_pitch_thres=5​

adahrs_xchk_roll_thres=8​

adahrs_xchk_hdg_thres=20​

adahrs_xchk_gmeter_thres=0.2​

adahrs_xchk_tc_thres=0.5​

adahrs_xchk_tr_thres=0.5​

adahrs_xchk_ias_thres=10​

adahrs_xchk_alt_thres=100​

adahrs_xchk_aoa_thres=0.01​

Hell if I can tell you what all of these mean - some are obvious, some a lot less so. I've bolded and italicized the two that I changed from the defaults. Only had one flight since then, but no errors thrown.