Localizer to Threshold 2

17.01.2008

Submission:

Maybe I was little bit unclear in my questioning. I have a runway, I know the threshold coordinates, and I know the position of the Loc. It's a normal conventional Localizer only procedure. The Loc is positioned only 225 m from the threshold of landing. The width of the Loc signal is not 210m at the threshold but at point B, ref Annex 10, 1050m beyond the threshold. That's why I asked of where to place the OAS area. It seems wrong to position the point of the threshold of the OAS at this runways threshold position. I know in some other countries one create a fictitious threshold 2000m before the Loc and place the OAS template there.
Susanne Westman - Procedure designer, Sweden

Answer or Commentary:

(I.W.
I would probably do that.

Place the OAS threshold at the position where the LLZ width is at 210m but use the minimum LLZ to threshold distance of 2000m in the construction of the OAS areas. I think you will have to make sure that the MAPt is prior to the fictitious threshold point (i.e. the LLZ 210m width point). Does any one else have ideas?)