Morning, the option to "deselect SLS" should result in FLS being defaulted. At the moment this isn't the case.

Thanks

7 hours ago, Adrian350 said:

Morning, the option to "deselect SLS" should result in FLS being defaulted. At the moment this isn't the case.

Thanks

Hi, are you able to record a video adding the issue, I am not as familiar with SLS/FLS unless I'm just mis-remembering. Thank you

I’m not entirely sure how it works on the 350, but I imagine it’s the same as generic Airbus logic.

FLS is a system which allows rnav approaches to b be flown with the same indications as ILS approaches.

It’s often an option rather than default, and can only be used on rnav approaches with a straight approach.

If you activate the LS push button and there is a straight in approach with FLS available, the final approach modes will be

F-G/S and F-LOC.

But for any rnav approach if you don’t activate LS you should get FINAL, APP NAV and then FINAL APP when both are captured.

Similarly if you try to use LS but it’s a curved approach and FLS is not available it still should be FINAL, APP NAV, and then FINAL APP.

But the a350 is currently treating all rnav approaches as FLS an it seems to be impossible to get the standard FINAL, APP NAV, and FINAL APP.

15 minutes ago, dectenor2 said:

I’m not entirely sure how it works on the 350, but I imagine it’s the same as generic Airbus logic.

FLS is a system which allows rnav approaches to b be flown with the same indications as ILS approaches.

It’s often an option rather than default, and can only be used on rnav approaches with a straight approach.

If you activate the LS push button and there is a straight in approach with FLS available, the final approach modes will be

F-G/S and F-LOC.

But for any rnav approach if you don’t activate LS you should get FINAL, APP NAV and then FINAL APP when both are captured.

Similarly if you try to use LS but it’s a curved approach and FLS is not available it still should be FINAL, APP NAV, and then FINAL APP.

But the a350 is currently treating all rnav approaches as FLS an it seems to be impossible to get the standard FINAL, APP NAV, and FINAL APP.

Got it, thanks.

I'll pass this along to the team.

Hi,

First of all, the A350 does not have a FINAL, APP NAV or FINAL APP modes. Please do not implement these. Unlike in the older Airbuses, FLS is installed by default in the A350 and it is used for RNP approaches with LNAV/VNAV and LNAV minimas. It can also create an "ILS-like" indication for some LOC and VOR approaches.

As Adrian said, when you press the DESELECT SLS button, it should give you the FLS indication so that you can fly an RNP approach with LNAV/VNAV or LNAV minima. Now it seems to give you the vertical guidance of the APP DES mode, which is only meant for the RNP AR approaches. In the current version, it looks like the FLS is only available for those RNP approach procedures, which do not have a LPV SBAS approach associated with them.

This is how it looks like at the moment. This approach (EDDH RNP 23) has LPV, LNAV/VNAV and LNAV approaches in the same procedure. The default is LPV (flown with SLS). When you press the DESELECT SLS button, it brings up the vertical guidance of the APP DES mode (in the screenshot).

This is the FLS indication (the double diamonds) you should get after pressing the DESELECT SLS button:

Edited 4 hours ago4 hr by ool

1 hour ago, ool said:

Hi,

First of all, the A350 does not have a FINAL, APP NAV or FINAL APP modes. Please do not implement these. Unlike in the older Airbuses, FLS is installed by default in the A350 and it is used for RNP approaches with LNAV/VNAV and LNAV minimas. It can also create an "ILS-like" indication for some LOC and VOR approaches.

I was able to find information corroborating your statement here within the Safety Airbus Website as I agree with this being the case as it's something I've been told before, what I had logged was regarding Deselecting SLS, I still am working on keyboard clarity when addressing multiple issues in one post; https://safetyfirst.airbus.com/lets-use-xls/?airbus-iframe=true&airbus-post=2048