Help Understanding Airbus (SRS, Runway, Auto Thrust Blue)

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1

Good evening forum,

Looking for some help from the Airbus experts. I understand the FMA call outs, and what they mean and the different variations.

However, I am looking for a better understanding of the Runway portion.

I understand this is the lateral guidance during takeoff and utilizes the localizer beacon to achieve this but am trying to understand the following;

  • Is this used whenever it is available
  • Is it only used when available and certain criteria (weather) call for it?

Those are the first two questions, but one mental block I can’t seem to overcome is this one.

Which localizer is it using?

Example,

Runway 06L/24R

Let’s assume both runways have an ILS and I am taking off of 06L.

  • Am I entering the ILS of 06L (which would technically be behind me as I sit on the runway)?
  • Am I entering the ILS of 24R (which would technically be infront of me as I sit on the runway)

Lastly, for the CRS of each, is it Front or Back?

For whatever reason I can’t seem to do the math on this equation and hoping someone can show me how to get to the answer :slight_smile:

Bonus question (if you know) I know Boeing doesn’t have this for an FMA, but do they do the same thing with their tuning?

Thanks in advance!

2

Take a look here and see if that helps.

3

Thanks for those, I completely understand the logic behind it all, and that it also auto tunes.

Just trying to understand a few concepts that this doesn’t cover.

Which Localizer is it using? (in my example, taking off runway 06L) is it using the ILS for 06L that you would use if landing on that runway?

And if so, would that be Fcourse or Bcourse

Or, is it using the localizer for Runway 24 (if you were landing on 24) and same, F or B (forward or back).

I guess to answer part A I could just go into RADNAV and look and see what it programmed for the frequency and then check the charts, but the CRS is usually blank if I recall.

4

The localizer is at the departure end of the respective runway, not at the approach end.

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5

Perfect, so if taking off 06L it would be the localizer of 24R.

And then I would assume, course would be Forward 057?

6

No, my understanding is that for both takeoff and landing in your case at RW06L, you would tune to the 06L localizer with course set at 057.

In both of those instances the physical location of the localizer and glide slope equipment is in front of you past the departure end of the runway.

7

Ahhh okay I see what you’re saying!

I’ll test it out, thank you :slight_smile:

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