We did have a trial into the London TMA about 4 years ago when operators had agreed that 270kts was a reasonable speed for both fuel efficiency and the operation of the network as a whole. Unfortunately the procedure was poorly released to the ATCOs so quickly fell into disrepute despite analysis showing that operators were benefitting in terms of reduced fuel burn.
Some operators (EZY) continue to use 270kts or less as their normal speed so it is always frustrating to hear ATCOs actually speeding them up to stay in front of another company aircraft. In actual fact even some of the more notorious high speed merchants have significantly reduced their descent speeds even though they may have an unrealistic 25 minute turn round to make.
I think it is time that 270kts trial was re-introduced with better communication and training to the ATCOs.
There will always be times when it will be necessary to use high speed but if a speed range 240-270 kts is better for the operators than 270-300kts then why don't we use it and increase awareness of the reasons for it. It does also allow significantly more thinking time on a busy sector.
Last edited by 250 kts; 2nd July 2012 at 08:37.