Speed restriction @ LHR

[comeflymark]

When departing London Airports, one is generally given 'no ATC speed restriction' or 'no speed'.

This instruction allows one to increase speed to above 250 knots <10,000ft but not until passing 4,000ft AGL.

Can any bookworm quote the reference for this 'local' regulation. Doesn't seem to be in the Jeppesen Airfield Booklets.

Cheers

[5milesbaby]

Look in the UK Air Pilot at the SID charts for all the London TMA airports that have SID's associated (EGLL/KK/GW/SS/LC). Under general information at the top is always a point saying "Max IAS 250KT below FL100 unless otherwise authorised." There is no mention on any of them about passing 4000'. All the STAR charts have Speed Limit Points too where a/c must be <250kts unless otherwise authorised.

[ebenezer]

comeflymark - Several operators do however, impose their own Company speed limits on departure in order to ensure that aircraft maintain the correct SID lateral profile where there is a large turn after take-off e.g. Gatwick westerly DVR SIDs and Luton easterly CPT SIDs.

Irrespective of the instruction "No ATC speed restriction" it's up to the flight deck to ensure that they follow the SID lateral profile due to the close interaction of many LTMA SIDs.

The 4000 feet restriction to which you refer is probably the Noise Preferential Route (NPR) altitude ceiling above which ATC can legitimately radar vector you off the SID (all LTMA SIDs incorporate the applicable NPRs). This has nothing to do with SID speed limits.

;)