Fully managed RNAV approache issue A319 Pro

[Island Flyer 0]

Thank you guys for a great product.

 

I have noticed that the fully managed RNAV approaches are not working properly on the A319 Professional. On reaching the final approach fix at the platform height with approach mode armed, FINAL APP at this point has still not engaged and the aircraft levels off at the FCU selected ALT instead of continuing to follow the VDEV profile. 

 

If the approach at this this point is flown NAV/FPA with the Aproach mode still armed, the FINAL APP only engages between the last waypoint in the profile and the runway threshold. As a work around, if the fully managed approach is flown with the an FCU alt selected below the crossing height of the last waypoint in the vertical profile then the FINAL APP engages after passing this last point. I do not know if this is only an issue on the approaches that I have flown , or if other RNAV approaches are also effected. The approaches that I have noticed this on are FIMP RNAV 32, FIMP RNAV 14 & FMEP RNAV 15.

 

The FINAL APP should engage long before the FAF (possible even at a waypoint prior to the FAF), and although a work around is possible it is not able to be flown correctly according to Airbus procedures. 

 

I have seen a thread regarding the same phenomenon on the forum which had been closed off due to the issue being resolved, however I am experiencing it on these approaches. Please would the developers be so kind as to remedy this in the next update as being a real world 319 pilot it is counter productive having to adapt procedures to make it work.

 

Thanks again.

 

 

[Aerosoft Team [Inactive Account] 51558]

Could you give is us flightplan and RNAV approach used for this?

[Island Flyer 0]

Hi Mathijs

 

Thanks for your reply.

 

I have done some further experimenting with other fully managed RNAV approaches. The issue is not present on all RNAV approaches. If the final approach fix (FAF), indicated as (F) on Lido charts,  is at the platform height the FINAL APP will engage shortly after passing the FAF. However on RNAV approaches where the FAF is below the platform height, ie on the descent profile, the FINAL APP will only engage shortly after passing the FAF while the aircraft is still maintaining the platform height. In this case on such approaches the aircraft can be way high above the profile before the FINAL APP engages with excessive nose down pitch and rate of descent to regain the profile. 

 

This is evident on the following approaches, regardless of the STAR or transition:

 

Mauritius - FIMP RNAV(GNSS) 32 (VIA EVOTU)

Tanzania Kilimanjaro - HTKJ RNAV(GNSS) 27 (VIA GABNI)

Switzerland Geneva - LSGG RNAV(GNSS) 22 (VIA SPR) - In this case the aircraft is maintain 7000FT passing GG808, 3000FT above profile, when FINAL APP engages. With the APPROACH mode armed the FINAL APP should already have engaged at or before SPR at 7000ft.

 

All of the above approaches have in common the FAF on a descending segment. Approaches that work fully managed such as LSZH RNAV(GNSS) 14 and many others, have the FAF at the start of the final descent segment. 

 

Although I have not yet tried it, I would imagine that this issue may also be the evident with certain fully manged VOR approaches too where the FAF is on the final descent segment.

 

Trust this helps.

 

 

[Secondator 643]

Thanks Island Flyer,

I will test this out and see what happens on my side to confirm it.

[Jockos 5]

Very interesting thread and possibly why I have a 'mixed' success at Managed RNAV's.

I think almost all the RNAV's I fly, the IAF would  always be above the FAF.

I will set my altitude at the FAF height (which I think is technically, incorrect given that the FAF is below the IAF) and see if it will descend after FAF.

Thanks for the input here, folks.

 

Cheers