pa,
(1) Looking at my Aerad guide I see that the above departures may be offered to aircraft normally allocated LAM/CLN SIDs and DVR SIDs (from Gatwick) respectively. Is this to spread the outbound load when a number of departures with ultimately the same routing are offering, or are there other reasons?
WIZAD and TIGER departures are used tactically to expedite traffic as required.
Certain (noisy) aircraft aren't allowed to fly them.
Don't see them being used as often as they used to be, especially the WIZADs.
Ideal time for a WIZ might be to send a slow prop aircraft one way and all the jets the other so the prop doesn't hold up the jets, if you see what I mean. Not that many prop aircraft flying into Gatwick these days so not quite the same need to split the departures.
WF.