Precision Approaches-GTN650/Skyview

I am relatively new to the Dynon Skview Classic and GTN 650W combo. I've recently completed phase 1 so I think it's safe to say I'm still a novice with these particular systems. My day job however has allowed me to log a few thousand hours behind a G1000 and at least one hundred precision approaches so I know what lateral and vertical guidance during an approach should look it. While attempting to fly an LPV in my -8 (in VFR conditions), I was not able to bring up vertical guidance on my Skyview PFD. I spoke with a Dynon representative who advised the Pathways need to be activated to do so. This doesn't exactly make sense to me as I'm talking about the vertical guidance (diamond) to the right of the HSI on the PFD. Plus, I don't particularly like to fly with the pathways activated. My HSI source is set to the Garmin and my lateral guidance works appropriately. I am hoping that someone out there has worked through this issue so I don't have to re-nvent the wheel, again...
Thanks in advance!!!

Did you press the VNAV button on the Dynon before intercepting the vertical path? Basically, think of the Dynon as only doing what it's told by the 650, but you have to enable the VNAV function first. I think what the Dynon rep may been telling you (and using perhaps the wrong term) is to enable VNAV. You don't have to have HITS enabled

Mark, thanks for the response. VNAV is an autopilot function. I'm just talking about what the 650 is sending to the Skyview while hand flying. I am not receiving vertical guidance (LPV Approach) on the Skyview display.

He is right. Hit vnav and the vertical guidance tape appears and gives the guidance. You don’t have to activate the ap.

...and hitting VNAV will give you flight director vertical steering if you?re hand-flying the needles/bat wings (autopilot deselected). If you also selected NAV, you?ll have lateral/roll mode steering for the approach.

Another perhaps oversimplified way to look at it is that the FD is the "brains" and the AP is the "muscle". All those modes are really to command the FD and the FD in turn tells the AP what to do

Guys, thanks for the input. On one LPV approach I had the AP on and Nav and VNAV selected (since there is no APPR button). No Vnav reference displayed. It could be user error as I said I?m still new to Dynon. I will try it again my next opportunity. I will also try an ILS. Do any of you remember having to do any specific configuring? My FD and AP will provide IAS or VS climbs or descents. It seems getting approach vertical guidance is the only issue. If you have any specific advise feel free to PM me and I?ll reach out.
Thanks, DG

I know of no setting on either the 650 or the Skyview that affects the glidepath functionality. If Skyview is getting guidance from the 650, your ARINC hookup would appear to be properly set up.

Assuming that you have activated the approach, it should show the glidepath indicator after you press the VNAV button. Notice I said "after" instead of "when" because for some reason, the Skyview delays showing the glidepath indicator until you get close to the glidepath. Like you, I have a bit of time in front of G1000s in a Bonanza and Cirrus. Pressing the APR button brings up the glidepath indicator immediately. In my first couple of LPV approaches with the Skyview, I pressed the VNAV button, it illuminated but no glidepath indicator. I must have punched that button 3 times and finally just left it punched and rode the approach in and voila, it finally popped up in time to ride the glidepath down. I am not sure what the logic is and why they delay showing that indicator but it's maddening. If you haven't tried it, just enable VNAV and fly the approach in and see if it will finally come up. If it doesn't, I would contact Dynon support and ask them what to do.

Just want until you hook up on a localizer approach and lose the localizer signal temporarily. instead of staying in VLOC mode, it switches to TRK mode without alerting you...so after the localizer signal comes back and you might think it would recapture it, well, you'd be wrong. It stays in TRK mode. Going to TRK mode when you lose the localizer makes sense, but it would be really nice if Skyview would alert you when that happens.

An important question

Denver,
Forgive me, but to ensure we're not all assuming what may (or may not) be obvious, please allow me this question:

Do you have the GTN650 and SkyView connected through an ARINC module? Something like Dynon's SV-ARINC-429 module, which puts both the Garmin and Dynon units on a common language?

If you said so earlier, forgive me...sorry, I missed it.

If not, then this may be your problem. Adding the SV-ARINC-429 module allowed my GTN650 to interface with my SkyView Classic flight director and autopilot settings, giving me all the green and magenta needle and glideslope guidance (green needle LOC/ILS and magenta needle LPV).

If you do have the ARINC module, well, I don't know what to tell you.

Walt?

And with it configured through the ARINC-429 module, then under the PFD menu, under the HSI Source button, do you have the 650 selected as the HSI source?

Mark Dickens said:

. In my first couple of LPV approaches with the Skyview, I pressed the VNAV button, it illuminated but no glidepath indicator. I must have punched that button 3 times and finally just left it punched and rode the approach in and voila, it finally popped up in time to ride the glidepath down. I am not sure what the logic is and why they delay showing that indicator but it's maddening.
ens.

Click to expand...

There are quite a few LPV approaches like this: IAF at 4000? (call it abcde), FAF at 2000? (call it vwxyz). The FAA approach chart appears to show a GS from abcde, down to vwxyz, continuing down to the MAP. But it?s not! Look at a Jepp chart for the same approach. The Jepp symbology makes it clear that from the IAF down to 2000? is a step-down descent, not a GS. You need to descend to 2000?, and, nearing the FAF, the GS will come alive. The Garmin navigators will not show a GS until nearing the FAF, if you?ve selected abcde as the IAF. The work-around is, once you?re established inbound, to select ?vectors to final?. The GS will come alive when you do this.

Pressing the VNAV button as nothing to do with whether or not the glide path or glide slope indicator appears on the Skyview EFIS. The VNAV button is purely an auto pilot function or FD too. Once you press VNAV the AP will track the GP/GS down.

I do not know why your indicator is not showing up on the efis, but I suspect you should call dynon tech support, if they can't help then try garmin..

Rv8Medic said:

I am relatively new to the Dynon Skview Classic and GTN 650W combo. I've recently completed phase 1 so I think it's safe to say I'm still a novice with these particular systems. My day job however has allowed me to log a few thousand hours behind a G1000 and at least one hundred precision approaches so I know what lateral and vertical guidance during an approach should look it. While attempting to fly an LPV in my -8 (in VFR conditions), I was not able to bring up vertical guidance on my Skyview PFD. I spoke with a Dynon representative who advised the Pathways need to be activated to do so. This doesn't exactly make sense to me as I'm talking about the vertical guidance (diamond) to the right of the HSI on the PFD. Plus, I don't particularly like to fly with the pathways activated. My HSI source is set to the Garmin and my lateral guidance works appropriately. I am hoping that someone out there has worked through this issue so I don't have to re-nvent the wheel, again...
Thanks in advance!!!

Click to expand...

Give me a call on Monday. 425-402-0433 I suspect this is an ARINC 429 configuration issue on the Garmin side. I have run across this exact issue with an Avidyne and it was a setting. It would work best with you in front of the equipment, but call me so we can set something up. Monday is crazy around here so I want to make sure I don't have you waiting for me to return a call.

I'm still a bit confused with this discussion and have experienced the same problem as RV8medic. We have essentially the same equipment, but I have a GNS430W instead of a 650. Lateral tracking with a G430 flight plan works as advertised. Using a G1000 as you approach an IAF with the AP in NAV and ALT, you press VNAV and set a lower altitude with the Altitude bug - usually the DA or DH. When you arrive at the IAF, the AP will fly the VPTH step-downs until the fix prior to the FAF. At that point it levels off until it captures the GP/GS and again starts the descent. So how much of that will the Dynon AP/FD fly. It's not clear to me from reading the Pilots Guide. Do I have to use VS and set the step-down altitudes from the IAF to the FAF then VNAV for the final? Or should it fly the whole shebang? I have not yet seen GP on an RNAV GPS approach, but have seen the GS display on an ILS. With VNAV selected, it did not capture the GS.

I also tried to use the 430 and AP to fly a descent using the VNAV function of the 430W. I entered to be at 1000 MSL at a waypoint along my flight plan descending at 400FPM. With AP in NAV/ALT and VNAV selected and the MSL set in the altitude bug, it did not start to descend when arriving at a VSR of 400FPM. I didn't it mention above, but the VNAV selection on the D700 seemed to function correctly as far as the highlighting described in the Pilot's guide, and was not grayed-out.

Mr. Jones, since I live close to RV8medic, I'll try to hook up with him when he calls on Monday.

BobTurner said:

There are quite a few LPV approaches like this: IAF at 4000? (call it abcde), FAF at 2000? (call it vwxyz). The FAA approach chart appears to show a GS from abcde, down to vwxyz, continuing down to the MAP. But it?s not! Look at a Jepp chart for the same approach. The Jepp symbology makes it clear that from the IAF down to 2000? is a step-down descent, not a GS. You need to descend to 2000?, and, nearing the FAF, the GS will come alive. The Garmin navigators will not show a GS until nearing the FAF, if you?ve selected abcde as the IAF. The work-around is, once you?re established inbound, to select ?vectors to final?. The GS will come alive when you do this.

Click to expand...

It sounds like I was connecting the the vnav button with the glideslope indication when they aren?t really connected and now that I think of it that way it makes sense. I think I was bringing some of my g1000 training and trying to make it fit the dynon world. Thanks for helping clear that up

I have the sky view / gtn 650 system as well. The v calc function in the gtn650 is just as a reference only. It will not comment the a/p to fly that decent. My understanding is that the gtn navigators and the g3x combo will do that after the last update, but don?t hold me to it. Since that doesn?t apply to me I haven?t followed that discussion closely.

My procedure is to activate the approach and fly the vectors onto the approach course and just shy of the faf I hit the vnav button. That typically presents the gs indicator and will cue the a/p to fly the gs down.

This combo will NOT (as far as I know) fly a step down from the iaf to the faf. That must be done manually with the manual entry of the altitude and the vs button and a feet per minute setting to get you there. That?s how I do it anyway.

I went up this morning to test this some more. Basically, I found that when I flew a full approach (cleared to the IAF), the glidepath indicator popped up at the IAF without any prompting by me. So apparently, the 650 sends an ARINC sentence to the Dynon telling it that it has VNAV info, so it shows the indicator at that point. Since the glidepath is up, you can then press the VNAV button so the FD will give guidance down the glidepath.

What I haven't done is test the vector to final scenario where you're vectored onto the final approach course inside the IAF to see how that works. I let the A/P do the flying and it flew down to minimums on course and without major pitch changes. Of course, you have to manage your power appropriately.

I've been able to arm VNAV any time I'm done using other vertical modes (IAS, VSI). So after the last step down fix, I arm VNAV and wait for GS intercept. GS indicator pops up and the plane starts down at intercept. Works like a champ whether I'm flying the entire procedure or doing vectors to final.

rwthompson67 said:

I've been able to arm VNAV any time I'm done using other vertical modes (IAS, VSI). So after the last step down fix, I arm VNAV and wait for GS intercept. GS indicator pops up and the plane starts down at intercept. Works like a champ whether I'm flying the entire procedure or doing vectors to final.

Click to expand...

Ah, that's interesting. I wish Dynon would publish their logic flow for this. More research flying is necessary!

Thanks Rick & Mark. It's still not very clear at what point the VNAV function will allow you to fly a descent with the autopilot, except for at the FAF. I finally finished some mods to my Rocket today, so as soon as I can get some VFR weather I intend to go out and do some experimentation, including the vectors to final scenario. I'll let you know what I find out.

Flight test results

The weather and work Gods finally conspired together and allowed me to test my GTN 650/Dynon Skyview combo. After a thorough review of the 650 and Dynon manuals, I am happy to report that both the ILS and LPV features (both vertical and lateral) worked flawlessly. I flew two ILS and two LPV approaches, one each hand flown and one each with the autopilot coupled. In order to hand fly either approach the appropriate source had to be placed in the 650 and the NAV button had to be pressed on the Skyview Autopilot Control Panel. The NAV button acts as an Approach button. In order for the autopilot to fly the vertical portion of the approach, the VNAV button had to be pressed as well. Both the ILS and LVP autopilot flown approaches were smooth and within a quarter of one degree of deflection even though it was quite bouncy. Thank you for all the responses and advise!!!
DG

Thanks Denver. Other than needing to do a bit more autopilot tuning due to trim alerts, I've been successful at both RNAV and ILS coupled approaches too. I just really wish I had installed the button and knob panels. That's probably my next mod.

swaneymj said:

Thanks Denver. Other than needing to do a bit more autopilot tuning due to trim alerts, I've been successful at both RNAV and ILS coupled approaches too. I just really wish I had installed the button and knob panels. That's probably my next mod.

Click to expand...

I did the same thing...they weren't available when I bought my setup, so had to add them later, but both are a huge help, especially the auto trim controller on the button panel