Il arrive que les ILS sont parfois décalées. Celle de Sion LSGS en est une. Même le site de VACC Suisse nous le communique. Voici ce qu'il dit :
ONLY FOR USERS OF X-PLANE:
In X-Plane, the localizer and glide path of the IGS approach in Sion (LSGS) are wrong. The course is 252° instead of 246° and the glide path is 4.99° instead of 6.00°. In addition, there is also a problem with the distance measurement (DME) and the PAPI is at a wrong position.
The VACC-SAG chart for this approach is based on the correct and real data!
Open the main folder "/Earth Nav Data" of X-Plane and change the file "nav.dat" as followed:
1st step - Correct the LLZ (246° instead of 252°!)