Thanks.
There are it seems in the UK no SIDs with a published speed limit of less than 250Kt. Is this because the SID designers don't allow it or because they feel it isn't required.
In the examples given, are the restrictions for track keeping, airspace requirements or separation purposes? I realise that pilots may not be aware of the reason for the limit but any information or opinions would be of help.
Manchester's LISTO 1S departure turns right almost 100 degrees after less than a mile and a half, then right another 40 after another 3 miles. By this time most aircraft have not started to accelerate but some have and make a wide turn. The speed limit is the usual 250Kt below FL100. An aircraft flying wide and then rejoining can be caught up by one flying the correct track having departed after.
A question for Heathrow Tower types. If you have two aircraft of similar type on the same route one after another and your speed table says 2 minutes. How long do you really give? Full 120 seconds between rotations or 5 miles or what? Would you be able to reduce the time between same route departures if there was a lower speed limit on the SID? i.e. Speed control of departures.
It seems in the case of the Gatwick departures mentioned that the lower speed limit is unofficial and just used by the pilots to assist in track keeping rather than imposed in the design.
Any more thoughts?