No, those are the exact same steps.

Detail: If being vectored, you are already in HDG mode. Once cleared for the approach, hit the APR button. Approach mode will arm. As you get within the approach gate, the CDI will switch to the LOC green needles (if the freq is loaded in the GTN). When GS is captured it will descend. This assumes you are vectored at an altitude that will intercept the GS.

LPV is the same except the needles stay pink.

It won’t manage the power settings for you.

With the Garmin/Collins combo, the Collins autopilot is almost always in heading mode, and you switch between NAV mode (called "GPSS" - Or GPS Steering) and HDG mode on the Garmin equipment. You can select modes using either a physical Garmin box (which has a heading bug and a GPSS<>HDG button) or the G600(txi) touch screen. So if you were being vectored for an ILS, Collins auto-pilot is in HDG mode and Garmin is also in HDG mode. If the approach is activated in the Garmin equipment (this of this as the thing you do when cleared), the Plane will turn onto final configured like this. It's similar to how you can be in HDG mode on a G1000 with NAV armed in order to capture an airway. Once established, you hit Approach on the autopilot. If you were flying to an IAP pilot-nav, all would be the similar, but you'd be in GPSS mode on the Garmin and HDG mode on the Collins autopilot.

With the Garmin/Collins combo, the Collins autopilot is almost always in heading mode, and you switch between NAV mode (called "GPSS" - Or GPS Steering) and HDG mode on the Garmin equipment. You can select modes using either a physical Garmin box (which has a heading bug and a GPSS<>HDG button) or the G600(txi) touch screen. So if you were being vectored for an ILS, Collins auto-pilot is in HDG mode and Garmin is also in HDG mode. If the approach is activated in the Garmin equipment (this of this as the thing you do when cleared), the Plane will turn onto final configured like this. It's similar to how you can be in HDG mode on a G1000 with NAV armed in order to capture an airway. Once established, you hit Approach on the autopilot. If you were flying to an IAP pilot-nav, all would be the similar, but you'd be in GPSS mode on the Garmin and HDG mode on the Collins autopilot.

Exactly. So instead of "Cleared approach" -> Press "Approach" on autopilot, you press "Activate Approach" on the G750. Traditional Garmin instruction is to activate the approach upon first vector. With this system, you wait. Slight change in SOP.

But yes, if you activate the approach and you aren't cleared onto final and the controller decides he wants you to cross final (super unlikely, but possible), you'd have to enter wings level model mode of the autopilot, cancel the approach in garmin, hand fly, or something.

I will say, the Piaggio is a train when hand flying. Trimmed up, the thing stays perfectly aligned.

I fly a TBM (G1000nxi) and a Piaggio (Garmin/Collins) and find going back and forth quite seamless.

I will echo this - Piaggio hand flies very nicely.

On my GTN + SPZ setup in the Citation, I do this when being vectored to an approach:

HDG mode on a heading vector.

Activate approach on GTN with either vectors to final or the final approach leg inbound.

When you get approach clearance, select APR. This arms localizer capture but leaves HDG mode operational. When the lateral needles are within one dot, it disables HDG mode and captures laterally and then arms GS capture. When you get GS intercept, it captures the glideslope.

At DH, either go around or FD/AP off, as appropriate.

If they vector you through final, the AP won't capture if you stayed in HDG mode without APR. The plane will fly through the final. They do this sometimes for spacing or other reasons, and usually tell you this explicitly.

When they give you a new vector, dial that heading. Or if they just say capture laterally, then hit APR and deselect HDG and the system will compute a 45 degree intercept on its own, turn to that heading, and capture. You can always select HDG and manually dial the heading vector, then reselect APR (manual HDG selection cancels APR arm). I tend to prefer going to HDG instead of letting the system do the 45 degree intercept so I can fine tune what I want on the intercept.

My practice is to activate the approach on the GTN as soon as I am being vectored, that is, off flight plan. If I am not being vectored, the GTN will auto sequence into the approach if it is loaded. Either way, the GTN is navigating before I am cleared for the approach. If I get all the way to the final course without clearance, the plane will track that but not capture glideslope since I am in NAV mode and not APR mode. Once cleared, then hit APR to arm GS capture. Being cleared for the approach means changing the FD/AP mode, not the GTN, in all cases.

I don't know if my way is any more proper or correct than any others, but I find it works pretty well. My method is what the SPZ pilot's guide uses for illustrating the ILS approach.

Mike C.

What you described is how it works on the GTN+APS65 setup in the Avanti as well.

And, FWIW, also how it works with the GNS530W+G600+M4D in the MU2.

I agree...that is likely how it happens in PL21.
My question was too Matt about how Garmin might be different and somehow spoils you.

I think the "Garmin spoils us" comment was Talman's, not mine.

But I do think Garmin is a tremendous value - and as the dominant player & a large company, I'm thankful they haven't yet turned into a Honeywell/Collins/etc. business model

I think the "Garmin spoils us" comment was Talman's, not mine.

But I do think Garmin is a tremendous value - and as the dominant player & a large company, I'm thankful they haven't yet turned into a Honeywell/Collins/etc. business model

Mike, once again you probably just saved me thousands of dollars. I have been having what I thought was an intermittent problem where APR mode would cancel itself sometimes. I couldn't figure out what was causing it but based on what you said above, that may be it. I may be selecting APR too early while I'm still being vectored and it is canceling due to changing the HDG input. I have always caught it before intercept as the scoreboard is part of my scan. I was able to simply press APR again and it would capture and fly just fine. But it surprised me every time.

Yes, I know I need to install a GoPro to capture my panel in order to debug these things but it's just not something I'm excited about doing....

Changing the heading bug should not cancel APR arm. At least, I don't think it does that on my plane.

If you engage HDG mode on the FD panel, it will cancel APR arm, I believe.

APR arm cancel may occur if the localizer flags out during maneuvering. This can happen if you are too far out or too far off line of the localizer, or maybe brief radio interference.

I generally only APR arm when on the segment into the FAF or about to capture it, so I have a strong localizer signal, or I'm doing LPV which doesn't have these issues.

Is your problem on ILS or both ILS and LPV? If ILS, then the signal flag may be the issue. If it occurs on ILS and LPV, then it is some glitchy signal somewhere.


I video all my flights, the panel and outside. It has saved me absolute TONS of money and helped diagnose things quickly. Your memory recall of events is faulty and you will miss details without the video.

Mike C.

It definitely occurs on LPV. I was worried that it was a glitchy signal between the Garmin stuff and the FD and was planning to pull all of the connectors in the nose and hit them w/ contact cleaner in the Fall to see if that would fix it. But after your post it's possible that I'm doing something to cause it happen like using HDG mode to get around the bank angle limitation in NAV mode. Armed with this info I will make an effort to watch what I'm doing when it happens again.

Looking good at Bar Harbor today.

Collins PL21 (and FUSION).

Flying King Air with PL21 (or FUSION), I noticed that most pilots are not always clear of the differences between NAV and APPR functions when flying an approach.

Use VNAV + APPR when flying to a DA (ILS, LPV, LNAV/VNAV or LNAV using CDFA).
The aircraft FD and/or AP will not stop at the DA and will continue down on the glidepath towards the runway. If needed, the pilot has to initiate the go-around at DA.

Use VNAV + NAV when flying to a MDA (LNAV only, NDB, VOR not using CDFA).
The aircraft FD and/or AP will stop descending and level off at the MDA. Remember to increase power, so not to slow down and stall.

This should also apply to the Avanti with Pro Line 21.

CDFA (or +V) is preferred for approaches published with MDA minima only. In a King Air I add 50 ft to the MDA and that's my DA.

Here are some slides from Eric Berger at Collins: