I have read through manual and various checklists, but I miss ti find anything about who an when to set the GPWS Flap switch.

It doesn´t seem that the FO sets the GPWS Flaps switch he simply reads actually position.

This is with using button control !

Captain has to set it in FS2Crew. I *think* I usually set this pre-flight flows and definitely before the flaps are extended during taxi. You set it the position you would require if you were to return to your departure airfield.

I set it again before the descent/approach checklist, with my planned landing flap setting.

It's all described here:

http://www.support.fs2crew.com/help/manuals/#pageid=flows4

Just do a text search for GPWS

Thank You both for Your feedback.

 

Right - I now see in the "Originating" Flow : EGPWS - SET RETURN TO LAND FLAP SETTING

I just understood it to be set back to 10°, But offcourse the correct setting will be needed, should You need to return to Your departure airport.

10 is an unusual landing flap, 15 would be most common and 35 for steeper approaches and shorter runways

1 hour ago, ckyliu said:

10 is an unusual landing flap, 15 would be most common and 35 for steeper approaches and shorter runways

Yes - so I guess normally the switch would remain at 15° also in between flights - so 10° is just Majestics default setting.