You fly the prescribed speed required in the AIP: 220 kts at FL140 and below, and standard ICAO above FL140. The GD for an A380 is roughly 195-200 KIAS (weight dependent). ATC in LHR are very aware you are a 'Super" and knocking off 30 kts will take time, they give you plenty of time for speed reduction and a good read of the arrival procedures in your manuals will give you clarity of what to expect. It is unlikely you will need to 'level off', I would say that in my experience Heathrow and Gatwick Directors provide the best ATC service in the world, they announce track miles to you so you can easily accomplish a Continuous Descent Approach.
Last edited by Thridle Op Des; 18th Sep 2016 at 07:50.
Reason: Grammer