Updated 5 February 2019
The disappearance of MH370 highlighted a pressing need for aircraft position to be reported and recorded. It has been announced that the UK Air Traffic Control provider - National Air Traffic Services (NATS) - has taken a 10% stake in USA based Aereon - NATS takes equity stake in Aireon. It is claimed that this will help accelerate the technology required for global aviation surveillance.
See Aireon - Space based ADS-B
Through a network of 66 low Earth orbiting Iridium® NEXT satellites, AireonSM
will monitor the location of Automatic Dependent Surveillance-Broadcast
(ADS-B) equipped aircraft flying anywhere in the world, transforming
the way air traffic control services are provided.