Automatic VOR selection on the 320?
 

how the Airbus select his 2 VORs for his navigation, strongest or closest? aligned, not aligned? I would like to know if you know some rules that engineers have implemented in the system....

Hi
It takes into account any VOR in your flight plan. It'll auto tune to it. If there isn't, then based on certain criterias. Look into FCOM 1 and FMGS. Answer is there, sorry abit lazy to look thru it now.:)

As far as I remember, according FCOM 4 (should be round 4.3), FMGS autotune and elaborate VORs geographic coordinates for computing position according their "class of merit".
You can find it inserting tha 3 letter VORs code in the navaid page.
Hope this helps.

The FMGC will tune the VORs and the ADF according to the following priorities:

1. Anything tuned via the RMPs
2. Anything manually tuned.
3. VOR/D required for SID/STAR/App
4. To Wpt (Normally restricted to 130nm)
5. Fm Wpt.
6. Down Tk Wpt
7. Closest.

Cheers
mcdhu

A good Rnav will select at least one VOR off to the side when available, to provide better position determination via triangulation. More importantly, it is looking at the associated DMEs, as DME-DME gives better accuracy than VOR-DME or VOR-VOR.

GB