A quick look at MATS Part 1 shows that there is a provision to cater for 250 knots below FL100 in Class D, for aircraft that are not already exempt. This obviously seems to contradict regulation that has been quoted in earlier comments.
3A. Airspace Speed Limit
3A.1 Aircraft flying below FL100 are required to observe, with exceptions, a speed limit of 250 kt IAS. Such a limit is an essential component of the ‘see and avoid’ principle when separation is not established by ATC. This is in addition to speed limits, which may be
notified for specific procedures.
3A.2 The 250 kt speed limit does not apply to:
(1) flights in Class A and B airspace;
(2) IFR flights in Class C airspace;
(3) VFR flights in Class C airspace when approved in MATS Part 2 and authorised by an ATC unit;
(4) flights in Class D airspace when approved in MATS 2 and authorised by an ATC unit;
Note: Aircraft type and Aircraft Operator combinations exempt from the Class D airspace speed restriction on departure are published in the UK AIP associated to the aerodrome to which they apply.
(5) test flights in accordance with specified conditions;
(6) aircraft taking part in flying displays when authorised by the CAA;
(7) aircraft subject to a written permission granted by the CAA;
(8) State aircraft such as military aircraft.
Does anyone know if there is provision in MATS Pt 2 at Prestwick for allowing 250 knots below FL100 for Edinburgh outbounds, which would correlate with the AIP? If so then any idea why there is a difference between Glasgow and Edinburgh?