Up until recently I have been programming my approach into Pilot2ATC as part of filing the flight plan. After doing some further research and in another post, I came to learn that the approach portion would not be filed and that would be assigned en route by ATC.
With that in mind, I set P2ATC to assign approaches.
The last 2 approaches have been vectors then cleared for RNAV. I put the approach into the G1000 and then activate the vectors (forget the exact wording).
I get the straight out magenta line from the runway and I follow the headings as instructed.
Once I am cleared for the RNAV approach, this is where things kind of fall apart.
I’m at the correct altitude and just before the FaF I activate approach mode but it never actually seems to pick up.
The other question I had is once I am cleared, should I be activating NAV mode and let the GPS bring me into the FaF? And then once on it acticate APR?
I tried that, and the GPS doesn’t pick up I had to hand fly it in both times.
Any assistance would be appreciated, prior to this all approaches (ILS / RNAV) were pre-programmed so quite easy to fly.
RNAV approaches ain’t automated in the vertical axis, only the horizontal. IOW, the autopilot will maintain runway heading only. It’s up to you to manage your speed and attitude to slide on down the glideslope. Now, on an RNAV approach, when you go to APR mode you WILL get a glideslope indicator on the G1000 which makes it SEEM like it the vertical SHOULD be automated, but it ain’t. That’s just the fancy glass computer showing you where the glideslope is so you can follow it on down manually more easily.
This is in contrast to an ILS approach where the autopilot WILL follow the glideslope as well as staying on the localizer. But both are radio nav aids so you must tune the appropriate nav radio to the localizer’s freq for this to work.
I’ve been flying RNAV approaches in the Kodiak and I definitely get automated vertical guidance if I have APR mode on. Brings me right down to the RW without touching anything.
RNAV is used very broadly and can mean many things.
You can have an RNAV approach either with or without vertical guidance. With vertical guidance, it can be called an RNAV LPV approach (RNAV Localizer Performance with Vertical Guidance). I think there are other descriptions and acronyms that also come with RNAV approaches, and I don’t remember them all or recall all of the differences.
But, I think in short, you know if an approach is ILS, you have lateral and vertical guidance. If you are told an approach is RNAV, you need more information to determine if you will have vertical guidance or not.
Well, I may need to clarify a bit more. My lack of expertise is well established, but RNAV approaches might all have vertical guidance, but with different accuracies and minimum decision heights. LPV is the most accurate with lowest minimums. I think a “generic” RNAV will still have a glide path calculated.
I could have been confusing LNAV + VNAV guidance, which is even more confusing and can have vertical guidance or it might not depending on type.
Anyway, a couple questions. Are you using the G1000 NXi, or the stock G1000?
In your PFD, do you see the lateral and vertical path indicators show up in approach mode? Does “GP” show up in white when you arm approach, and does it turn green when your vertical guidance indicator comes down and hits your altitude?
Could you post a screenshot both before and after you arm approach?
Its the G1000 NXi. I usually turn on APR as soon as I’m on the final approach bearing to the RW and the GP goes green as soon as I reach the Faf. The magenta vertical guidance indicator is always present in the PFD at this point so I sometimes just hand fly it down but if visibility is an issue I let the AP take over.
And yes I should have added a bit more detail, apologies, It is an LPV approach which does show in the PFD and I am using the G1000NXi.
When I do an RNAV LPV approach by flying the approach procedure start to finish, it all works fine I can step down with VNAV, arm approach and pick up the glide path.
What I seem to be sturggling with is when ATC is vectoring me so I"m not flying the approach programmed into the G1000. I setup the approach and activate vectors. So once I’m cleared and on the path I arm approach but it never seems to pick up.
I’ll grab a screenshot today, wasn’t sure if there was a step somewhere I was missing by using the vector method.
After a few practice runs today I was able to successfully get it working.
I wasn’t paying attention (or didn’t know enough) to see that GPS was in Grey and HDG active so I kept messing with the APR button thinking I needed to enable it.
With @Crunchmeister71 help watching my stream I was able to navigate it and see what was active verse armed and when they switch over.
Flew a couple missed approaches to practice and vectored back around and got it on the ground as planned.
LNAV = lateral navigation, or the RNAV equivalent of a localizer. Left/Right guidance only.
LNAV/VNAV = both lateral and vertical navigation
LPV as already stated, localizer performance with vertical guidance. More accurate than LNAV/VNAV, with the lowest minimums. The RNAV equivalent of an ILS, often has the same minimums as an ILS (usually 200 feet).
All, repeat ALL, RNAV approaches are legally-speaking non-precision approaches.
