The perfect flight
At the world's busiest international airport, Heathrow's air traffic controllers look after over 80 landings and departures an hour. At busy times, the aircraft are likely to stack and circle over London until there is room for them to land.
With the UK's air traffic control company (NATS) striving to cut carbon emissions by 10% by March 2020 and the global airline industry committing to carbon neutral growth from 2020, unblocking congestion in the air has become a priority.
This led to the concept of the 'Perfect Flight', which NATS, British Airways and Heathrow worked out through the 'Sustainable Aviation' partnership. This demonstrates how in the future, flights could be more fuel-efficient and create less of an impact on the environment.
The Perfect Flight was flown on a normal British Airways service from Heathrow to Edinburgh. Every element of its journey was optimised to minimise emissions and delays.
The plane was allowed to taxi without having to wait on the ground, take off in a continuous climb - rather than a series of steps - to reach cruising altitude and make a continuous descent. After landing, the flight crew shut down one engine during its taxi to the gate.
The results were impressive. The flight used 350kg less fuel than normal, saving the equivalent of almost 1 tonne of CO2 - enough to fill five double decker buses.
While it isn't yet possible for every flight to be a 'Perfect Flight' this demonstration marks an important environmental milestone, and the information gathered will support the aviation industry to reduce emissions in the future.