Avidyne Homepage
Forum Home Forum Home > Avidyne General > IFD 5 Series & IFD 4 Series Touch Screen GPS/NAV/COM
  New Posts New Posts RSS Feed - GPS approach with non-initial fix?
  FAQ FAQ  Forum Search   Register Register  Login Login

GPS approach with non-initial fix?
 Post Reply Post Reply
Author
Message
  Topic Search Topic Search  Topic Options Topic Options
jzawodn View Drop Down
Groupie
Groupie
Avatar

Joined: 29 Apr 2015
Location: Groveland, CA
Status: Offline
Points: 43 		Post Options Post Options   Thanks (0) Thanks(0)   Quote jzawodn Quote  Post ReplyReply Direct Link To This Post Topic: GPS approach with non-initial fix?
    Posted: 21 Jul 2015 at 5:49pm
My instrument instructor has a scenario that I can't seem to find any guidance for in the 540's manual.

He says that a GPS approach can begin at any fix on the approach plate that's not the final approach fix (FAF). For example, if you look at the RNAV (GPS) RW 9 approach to E45 (our home airport):

http://155.178.201.160/d-tpp/1507/09084R9.PDF

ATC may instruct us to fly direct to UPCIM (an intermediate fix) if we're in a good position to do so. And that makes sense to me.

But I cannot figure out the right sequence of inputs or configuration to tell the IFD that I want to fly the RW 9 GPS approach starting at UPCIM. When I try to add the approach, I can choose HONEZ or HOFED (the two initial fixes) or Vectors. However, if I select Vectors it doesn't seem to sequence the approach as we'd expect.

So the short version of the question is this: how does one tell the IFD540 to use a GPS approach but begin it at an IF (intermediate fix) without having to manually fiddle with things as I'm trying to slow the plane down, get set for landing, and so on.

We haven't found a way to set that up. Or we're just Doing It Wrong[tm].

(Hopefully my question/scenario is clear...)

Thanks for any guidance or ideas,

Jeremy
Back to Top
B2C2 View Drop Down
Groupie
Groupie
Avatar

Joined: 05 Mar 2015
Location: california
Status: Offline
Points: 56 		Post Options Post Options   Thanks (0) Thanks(0)   Quote B2C2 Quote  Post ReplyReply Direct Link To This Post Posted: 21 Jul 2015 at 6:22pm
I think what you want to do here is load the GPS approach from, say, HONEZ, then on the fms strip hit the UPCIM waypoint box to highlight it and select the Direct to button and answer yes to fly direct to UPCIM. you are now flying the GPS approach starting at UPCIM. Try this on the ipad sim. I did and it seems to do what you want.
Back to Top
AviJake View Drop Down
Admin Group
Admin Group


Joined: 26 Mar 2009
Location: Lincoln MA
Status: Offline
Points: 2815 		Post Options Post Options   Thanks (0) Thanks(0)   Quote AviJake Quote  Post ReplyReply Direct Link To This Post Posted: 21 Jul 2015 at 6:47pm
Alternatively, you use the bottom right knob to scroll the cursor down to the desired leg (as B2C2 suggested above) but instead of hitting the Direct-To button, you get an "Activate Leg" line select key along the left edge of the page on the FPL tab.  
Steve Jacobson
sjacobson@avidyne.com
Back to Top
jzawodn View Drop Down
Groupie
Groupie
Avatar

Joined: 29 Apr 2015
Location: Groveland, CA
Status: Offline
Points: 43 		Post Options Post Options   Thanks (0) Thanks(0)   Quote jzawodn Quote  Post ReplyReply Direct Link To This Post Posted: 21 Jul 2015 at 6:49pm
Originally posted by B2C2 B2C2 wrote:

I think what you want to do here is load the GPS approach from, say, HONEZ, then on the fms strip hit the UPCIM waypoint box to highlight it and select the Direct to button and answer yes to fly direct to UPCIM. you are now flying the GPS approach starting at UPCIM. Try this on the ipad sim. I did and it seems to do what you want.

Ahh, ok. I hadn't thought to approach it that way (no pun intended).

I'll give a try tonight and see.

Thanks for the suggestion!

Jeremy
Back to Top
jzawodn View Drop Down
Groupie
Groupie
Avatar

Joined: 29 Apr 2015
Location: Groveland, CA
Status: Offline
Points: 43 		Post Options Post Options   Thanks (0) Thanks(0)   Quote jzawodn Quote  Post ReplyReply Direct Link To This Post Posted: 21 Jul 2015 at 7:17pm
OK, both of your answers work but I'm gonna say that B2C2's is "more correct" for this situation.

Here's why.

If I put in the approach and select one of the IAFs and then active the leg to UPCIM, it keeps the other legs (which I won't use) depicted, which isn't a big deal, but the nav box in the upper right of the Map page shows the DTK heading relative from the IAF not my current position. In other words, I don't know what heading to fly.

If I instead use the "Direct To" method in the FMS strip, it removes the unused legs, provides the proper DTK heading (relative to where I'm actually at) so I know which direction to fly, and generally does what I was hoping for.

Thanks to both of you. I learned a few new things about the 540 from your responses.

Jeremy
Back to Top
 Post Reply Post Reply
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.01
Copyright ©2001-2018 Web Wiz Ltd.

This page was generated in 0.070 seconds.