Teleport
That is a darn good question! Notwithstanding the fact that NATS manages the London airspace, the 2003 Air Transport White Paper put the responsibility for introducing ATC advances that would facilitate Heathrow & Stansted's expansion firmly in the lap of the CAA. NATS has been doing the work but the CAA has show an unwillingness to shift away from ICAO, which unfortunately is decades behind modern techniques.
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