Skyview/garmin 175 vertical glidepath indication is off

[bawduniak]

Is there a calibration that I need to do? The vertical glidepath indicator is off by several hundred feet when I fly approaches. The lateral indicator seems to be fine

 

[skysailor]

Are you positive you are showing the LPV guidance from the Garmin 175 and not the VNAV from the Skyview itself? When the firmware went to version 16 the VNAV presentation became the same as LPV. You must monitor the Skyview Flight Director source notations to differenciate. I considered it a possible safety issue so I returned to a later version 15. The depiction of LPV vs Skyview VNAV indications might vary depending on your settings.

 

[Dynon]

Are you positive you are showing the LPV guidance from the Garmin 175 and not the VNAV from the Skyview itself? When the firmware went to version 16 the VNAV presentation became the same as LPV. You must monitor the Skyview Flight Director source notations to differenciate. I considered it a possible safety issue so I returned to a later version 15. The depiction of LPV vs Skyview VNAV indications might vary depending on your settings.

Curious to learn more about the difficulty differentiating. Can you expand on it more? Not quite getting what you're describing here.

 

[skysailor]

Curious to learn more about the difficulty differentiating. Can you expand on it more? Not quite getting what you're describing here.

Happy to discuss by phone and have spoken to Dynon reps twice at Oshkosh regarding this. Firmware version 16 took the Skyview VNAV vertical path from the vertical speed tape and moved it down to the HSI and making the appearance the same as RNAV LPV or LNAV+V vertical guidance. ILS glideslope looks the same and is in the same place but easily differenciated as it is green. Users also lost the ability to arm Skyview VNAV as soon as top of climb is reached and cruise flight begins. Skyview VNAV (a VFR only assist) and RNAV vertical path (IFR) are both depicted in the same place and are the same magenta color. Referencing the flight guidance control area at the top of the PFD is the only way to tell what the flight director and autopilot are following. If a pilot were to be flying Skyview VNAV vertical path when they meant to fly RNAV vertical guidance, a safety issue could arise. Skyview vertical path is set by the user and is for reference only, providing no terrain or obstacle clearance. RNAV vertical guidance must provide terrain and obstacle clearance to meet TERPS criteria.

 

[DBRV10]

I have only ever seen HSI located GS but to be fair we have only recently had vertical guidance by GPS in Australia a short time. The HSI represents only what the Garmin outputs, and so far even the lowest grade LNAV+V has been spot on the approach profile every single timed we have done a lot of them over the last few years. So I am keen to see what it is you are talking about.

 

[skysailor]

I have only ever seen HSI located GS but to be fair we have only recently had vertical guidance by GPS in Australia a short time. The HSI represents only what the Garmin outputs, and so far even the lowest grade LNAV+V has been spot on the approach profile every single timed we have done a lot of them over the last few years. So I am keen to see what it is you are talking about.

As long as you are actually seeing the vertical guidance output from the certified receiver, it will be correct. Some folks have not been diligent in confirming the HSI source is the Garmin and not the Skyview. Combining this with the different display with Firmware version 16 is where the problem appears.

 

[bawduniak]

How do you configure the glideslope next to the HSI to read from my garmin 175. sure enough when I looked during the approach it says that the input is from the skyview. I have been playing with the setup menu but cannot figure out how to make that glideslope read from the garmin.

 

[skysailor]

You need the larger box to the right of the HSI to show GNS 175 (this will actually be whatever you labeled the Garmin in the setup of your ARINC 429). This is the HSI source. It will toggle between none, Skyview and any other navigation source you have configured in your system. The smaller box just below the larger one indicates what each of the RMI needles also shown on the HSI indicate. You choose the HSI source by selecting Auotpilot from the main page. The buttons along the bottom will now be labeled BACK, AP, FD, ROLL, PITCH, HSI SRC and LEVEL.. Each depression of the HSI SRC button will change the HSI source to the next in the sequence. The label in the HSI source (large box) will change each time you push the button. Be aware in the MAP menu you also can choose between flight plan sources. This flight plan source is only to show the flight plan graphically on the map. Ideally you would like the flight plan source and HSI source to be the same unit from which you are navigating. In your case, you want the map source and the HSI source to be the GNS 175. In the example below I am 25.9 miles south of the VQQ VOR with that as the active waypoint. The Autopilot and Flight Director are engaged. The HSI source is Skyview.

 

[rjones560]

Happy to discuss by phone and have spoken to Dynon reps twice at Oshkosh regarding this. Firmware version 16 took the Skyview VNAV vertical path from the vertical speed tape and moved it down to the HSI and making the appearance the same as RNAV LPV or LNAV+V vertical guidance. ILS glideslope looks the same and is in the same place but easily differenciated as it is green. Users also lost the ability to arm Skyview VNAV as soon as top of climb is reached and cruise flight begins. Skyview VNAV (a VFR only assist) and RNAV vertical path (IFR) are both depicted in the same place and are the same magenta color. Referencing the flight guidance control area at the top of the PFD is the only way to tell what the flight director and autopilot are following. If a pilot were to be flying Skyview VNAV vertical path when they meant to fly RNAV vertical guidance, a safety issue could arise. Skyview vertical path is set by the user and is for reference only, providing no terrain or obstacle clearance. RNAV vertical guidance must provide terrain and obstacle clearance to meet TERPS criteria.

I have a Garmin GTN650 that displays on the EHSI on the Skyview. Like the photo above the NAV source is displayed to the right of the EHSI there is never any doubt about which NAV source is being used. The NAV source displayed is running glide slope too. You can’t get information from both systems at once. The system that drives lateral is driving vertical.

 

[bawduniak]

You need the larger box to the right of the HSI to show GNS 175 (this will actually be whatever you labeled the Garmin in the setup of your ARINC 429). This is the HSI source. It will toggle between none, Skyview and any other navigation source you have configured in your system. The smaller box just below the larger one indicates what each of the RMI needles also shown on the HSI indicate. You choose the HSI source by selecting Auotpilot from the main page. The buttons along the bottom will now be labeled BACK, AP, FD, ROLL, PITCH, HSI SRC and LEVEL.. Each depression of the HSI SRC button will change the HSI source to the next in the sequence. The label in the HSI source (large box) will change each time you push the button. Be aware in the MAP menu you also can choose between flight plan sources. This flight plan source is only to show the flight plan graphically on the map. Ideally you would like the flight plan source and HSI source to be the same unit from which you are navigating. In your case, you want the map source and the HSI source to be the GNS 175. In the example below I am 25.9 miles south of the VQQ VOR with that as the active waypoint. The Autopilot and Flight Director are engaged. The HSI source is Skyview.View attachment 5033

Looking like avionics guy did not configure dynon to be listed as an hsi source how do I do that

 

[rjones560]

The Dynon Skyview system is the one displayed in the box to the right of the EHSI. If you want to use the Garmin 175 you have to switch to it. On the HDX1100 I just touch the box that displays the NAV source to change which source I am using. On your system you will have to look at the user manual to see how it is done. Check the HSI SRC button. If you don’t see the 175 there the ARINC 429 module is not installed correctly or possibly not configured correctly in the software. Call Dynon after you have investigated this or email them.
Remember that you can’t do approaches with the Skyview system. You have to use the Garmin 175 for everything.