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Problems with transitions


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Hi community,

I am (honestly said) new to commercial aviation. I am fairly familiar with VFR flying and tried to get into flightplanning with Simbrief and Navigraph. The point which still is not working for me is the last step from the STAR to the approach. For example if I fly from EDDM to EDDF and based on the planning select the correct STAR there is always a little gap between the last "waypoint" of the STAR and the actual ILS approach (transition DF454). The FMS (or MCDU as I fly an Airbus) also shows me a discontinuity for the flight plan.

I would be glad for anny assistance. The planned route is: EDDM/08R GIVM6E GIVMI Y101 ERNAS T161 FAWUR FAWU2C EDDF/07L.

Thanks in advance

Chris

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Look at the chart:

https://aip.dfs.de/basicIFR/scripts/getPage.php?part=AD&id=28CF65CA5D229601AC61A9A9122C2E65&title=AD 2 EDDF 3-1-21

As you can see, the track for FAWU2C ends at waypoint DF444, and there's a box that states in big bold letters:
 

Quote

MAINTAIN DOWNWIND TRACK BEYOND END POINT IF NO SUCCEEDING INSTRUCTION (VECTOR/CLEARANCE FOR APPROACH) IS RECEIVED

This means that you should fly the star as charted up to DF444, and then keep flying straight until you receive further instructions (typically, vectors onto a suitable intercept course, and then "cleared ILS"). The dotted arrow at the end of it also hints at this. A discontinuity in the FMS achieves exactly that: it will make the FMS "fall off" into the discontinuity, and maintain the current track, until you intervene, rather than advancing to the next waypoint.

In practice, the way it usually works at EDDF, EDDM, and other big German airports, is that you file the STAR, but ATC either clears you for a suitable transition, or starts vectoring you, long before you reach that point. In theory, they could clear you for the approach straight off the STAR, but I believe it's against policy to do that, they have to vector you onto a suitable intercept course before clearing for the approach.

Either way, you have to be ready to adapt to what they clear you for, but until they tell you what their plans for you are, it's best to leave that discontinuity in.

And in the case where you fly into those airports on Unicom, the usual rule holds: you have to "vector yourself", do what ATC would do (or at least a somewhat plausible approximation). So you'd fly the STAR up to DF444, check your altitude, and if it looks good, make a 90° turn towards the approach track, and then another 45° turn to get a nice intercept.

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Thank you very much.

I am still not so used to how adequatly read charts, but it makes perfect sense to me. In case of the FAWUR2C STAR I would have to make sure that at any point the ATC can also vector me to any of the initial approach fixes related to that runaway? I see on the chart they are marked as DF654, DF554 and DF454 (waypoints). As I try to understand the whole approach better would this also mean that in case I will receive a clearance from ATC that based on this I will have to continue the flightplan via a direct in the FMS?

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1 hour ago, Chris Kruger said:

In case of the FAWUR2C STAR I would have to make sure that at any point the ATC can also vector me to any of the initial approach fixes related to that runaway?

Yes, that is something you can expect.

1 hour ago, Chris Kruger said:

I will have to continue the flightplan via a direct in the FMS?

How you make it happen is up to you. You can do it with a DIRECT on the FMS, but personally I prefer to first point the nose in the right direction using HDG, which buys me a bit more time to properly change the FMS programming. It also avoids the situation where the FMS makes a boo-boo and makes me jump to a different point on the flight plan.

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Ok now all the pieces come together. 🙂

If I remeber correctly, but I am not an expert of the A320 yet, inserting a waypoint mostly will lead to bringing the plane into HDG mode as the FMS otherwise won't accept the addition. I suppose that to change the heading first is a the best choice to avoid problems like you mentioned.

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3 hours ago, Chris Kruger said:

I am still not so used to how adequatly read charts

Best go to YouTube and search for "how to read approach charts". It will come up with a long list of tutorial videos, pick one or two and ingest the information!

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1 hour ago, Chris Kruger said:

Ok now all the pieces come together. 🙂

If I remeber correctly, but I am not an expert of the A320 yet, inserting a waypoint mostly will lead to bringing the plane into HDG mode as the FMS otherwise won't accept the addition. I suppose that to change the heading first is a the best choice to avoid problems like you mentioned.

Yes, it's definitely good practice to switch to HDG before messing with the flightplan, even on aircraft types that don't force you to.

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To make this even clearer A320 MCDU shows these type of legs as MANUAL (or should show). So you know, that you are expected to do something and it is not just a "normal discontinuity".

In this case I have had two types of vectoring from ATC. One has been via vectors "turn right to heading 270, cleared for ILS..." and the other "direct BIFIX, cleared for ILS...".

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2 hours ago, Tobias Dammers said:

Yes, it's definitely good practice to switch to HDG before messing with the flightplan, even on aircraft types that don't force you to.

...until you know your plane really well. Then it is going to be easier to judge when this is necessary and when not.

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