Quieter departure procedures

Representatives on Luton’s Airspace Change Focus Group have been working for over a year to propose changes to the main westerly departure route towards Brookmans Park in order to alleviate the noise concentration cause by RNAV (GPS navigation).

The airport held out options for achieving higher altitude and for respite routes to share the noise burden, but the air traffic service NATS has now declared them unworkable until the whole airspace in the south-east is redesigned under the FASI-South project.

The recent experience does not come across as joined-up planning: all the routes and airspace users in this area are interlocked, and the freedom for any airport to improve things for people on the ground without synchronised cooperation from other airspace users is self-evidently very limited. Yet the CAA mandates a process in which each change is proposed by a particular airport sponsor, and a backlog of such proposals is awaiting attention in a queue. But on top of this, the DfT is organising a process to review the entire low-level airspace design which will affect all the airports. How?

Our own experience has been a year of frustration and apparently wasted effort: we were told that Luton was liaising with Heathrow and Stansted, but this did not produce results and the fact that NATS has identified that planes from those two airports get in the way of what Luton thought it could do, can hardly come as a surprise. Meanwhile we summarise the points we made to the Focus Group process:

Departure procedure
Aircraft take off at a steep angle to gain height quickly, then pull in the flaps and reduce the climb rate to accelerate at a shallower angle. The height at which this happens is known as the “acceleration altitude”. It has an impact on engine wear and fuel usage, but also on the noise of the aircraft. LADACAN wants open and transparent assessment to determine what is best for people, not just what is best for airlines.

Climb rate
If cleared by air traffic control for continuous climb, aircraft can proceed to 7,000ft and beyond. If other aircraft are flying above them, Luton departures can be held low at 4,000ft and 5,000ft for very extended distances, increasing low-level noise and pollution, and wasting fuel by flying far less efficiently. LADACAN wants the optimum rate of climb to be assessed by open and transparent investigation to assess noise at different points along the track, again to determine what is best for people, not just for airlines.

Airspace redesign
Many of Luton’s departures are held low in this way because of the antiquated design of airspace in the south-east, and the fact that Heathrow flights go over the top of Luton’s departure routes. LADACAN wants the DfT and CAA to tackle the redesign of airspace in the south-east in a joined-up way rather than on a piecemeal basis. Neighbouring airports will affect and constrain what each other can do to alleviate noise impact, and again the optimum solution for people on the ground is give-and-take which prevents (for example) Heathrow’s planes – and even local gliders – blocking what Luton’s planes need to do to reduce noise, as at present.