LSGG SID RWY 05 North

[Driver170 42]

The SID out of rwy 05 North (SIROD 5N) (ARBOS 7N) procedure is, straight ahead R045 GVA - at 7000 or D8 GVA, Whichever is later, turn left. But the FMS data still has you proceeding outbound another 2nm to D9.5 GVA then it proceeds left, this is also shown for the SID chart?

 

Why the two procedures? Or am i missing something guys?

[thepilot 577]

More information please... which AIRAC installed? Matching terminal charts (Jeppesen/Lido/Navtech, page #)?

 

Edit:

 

Jeppesen indeed says "Climb on GVA R-045, when passing 7000' but not before D8.0 GVA turn LEFT..."

 

To me this looks like an extension (or alternation) of the SID that in case you don't make 7000' before D9.5 GVA, you have to be at a minimum altitude of 3750' at that point, since you are still following GVA R-045 until you reach 7000' (which in this case would come later, of course).

[Driver170 42]

Latest AIRAC, LIDO charts.

 

I checked Switzerland AIP charts and they do have that extension but don't mention about turn left at D8 GVA or 7000 WEL.

 

Hmm i was thinking the same. I'm looking through the ICAO 8168 DOC to see anything about that procedure.

[Driver170 42]

Got a good answer

 

I would check the FMS prediction to see what altitude its estimating by the GVA8 point. It could be that it is expecting to be below 7000 at the GVA8 point. As the SID is 7000 or GVA8 whichever is later you need both criteria to be met before the turn is started. By that I mean 7000 has to be achieved and GVA8 has to be achieved.

 

As there is a ridge to the north it is important that both conditions are met before the turn.

 

Most jets will have achieved 7000 by GVA8 and therefore will turn at GVA8 as both criteria (7000 and GVA8) has been met and therefore it is safe to turn.

 

Pilots can either wait until the turn is started before setting STD (to ensure that the 7000' criteria is met and not FL070 which could be below 7000' and therefore not safe to turn. Or pilots may set standard as normal, keeping an eye on the backup altimeter which is set to QNH. If the aircraft starts before 7000' has been met then they will select and track straight ahead as per the SID and then re-engage NAV once 7000' has been achieved.

 

Personally I like to wait for the first turn but each to their own.