Noise management board update
Here Bo Redeborn updates on progress of the NMB at Gatwick
Bo Redeborn, who led the Arrivals Review and is the independent chair of the Noise Management Board (NMB), updates on progress made by the Board. You can find all minutes and documents relating to meetings on our NMB page.
Reduced night noise trial update
The proposal for the Reduced Night Noise trial originated from a challenge by our local communities to take action to reduce the noise that aircraft make when arriving at Gatwick.
Following this challenge a proposal to tackle the issue was first introduced in our Noise Management Board action plan in 2017.
No decision has yet been made on whether the trial will take place or not, although the planning process is still ongoing. The following questions and answers are designed to clarify some details related to the trial.
What is the reduced night noise trial?
The reduced night noise trial is a proposal to increase the height of low flying aircraft so that the noise they make on the ground below is reduced. During any trial, aircraft would also fly descents which will reduce noise.
During any trial, no more aircraft will fly at night than currently and nobody will be newly overflown.
The trial would be scheduled to run between the hours of 0130-0500 and, based on the results of similar approaches at Schiphol and Dublin airports, it is expected that the majority of residents who are currently overflown will experience less noise during the trial because the aircraft will be flying higher.
The trial will use more precise navigation technology – will this lead to a concentration of flights down a narrow flight path so that residents underneath experience more noise than before?
Some nights only a handful of aircraft will take part in the trial. At most the trial will involve around 12 to 15 aircraft a night and these will be dispersed across approximately four different arrival routes to avoid concentration, although the exact location of these routes has not yet been designed yet.
What is the new approach you are proposing?
Aircraft currently fly within a range of heights before joining the final approach for Gatwick’s runway, which means that some aircraft are flying lower than others. The trial will see if new satellite-based navigation technology can be used to lift these up so that they fly higher, and therefore make less noise on the ground below.
How long will the proposed trial last for?
The proposal is for a trial to operate for six months so that data can be collected to establish evidence whether this new approach reduces noise, or not.
Following concerns raised by community groups, a safeguard would also be in place to stop the trial if evidence demonstrates that aircraft noise is not reduced by the trial.
How will you collect and monitor the noise impact of the trial?
The final sites have still to be agreed but a range of noise monitors will, uniquely, be positioned further from Gatwick than ever before to help ensure that a comprehensive set of empirical results are collected over the six month period.
Where will the trial fly?
The current areas overflown are shown below in Figure 1 and the four proposed routes for the trial are shown in Figure 2. The proposed routes shown are indicative only and have not yet been finalised. They may therefore be subject to change.
It is expected that – based on the evidence from other airports - the majority of residents living under the highlighted areas in Figure 1 will experience less noise during the trial.
Many of the aircraft flying the routes in Figure 2 will also make less noise than currently as they will be flying higher.
Figure 1 - existing arrivals routes
Figure 2 - proposed trial routes
What will happen after the trial?
Aircraft will go back to flying the arrival routes they do today. The evidence from the trial will be examined by the Noise Management Board, including community groups, to assess whether the approach explored during the trial can be used in the future to reduce the noise from arriving aircraft.
The trial will not be used to identify new routes for future airspace design or increase capacity. Nor will the trial be used to introduce airspace change without consultation.
What are the next steps - when will the proposed trial start?
No decision has yet been taken on whether to proceed with the trial or not, however discussions looking at taking the trial forward are continuing with the CAA and through the Noise Management Board.
If a decision is taken to proceed with the trial, the next step would be to submit a Statement of Need to the CAA to start the formal process. As a ‘change sponsor’ Gatwick has to follow CAA guidance (CAP1616) for the process of conducting a trial before it can begin. This process includes conducting a safety assessment, engagement and approval. The CAA will ultimately have to sign off and approve the trial.
No date has yet been agreed for the start of any proposed trial.
Back in March 2017, during the fifth NMB, an initiative was proposed to reduce the noise that aircraft make when arriving at Gatwick. The initiative, with the support of our communities, would involve running a ‘Reduced Night Noise’ (RNN) trial (between the hours of 01.30 – 05.00s) to increase the height of low flying aircraft so the noise they make on the ground is reduced.
Based on the results of similar approaches at Schiphol and Dublin airports, it is expected the majority of residents who are currently overflown will experience less noise during the trial because the aircraft will be flying higher. It is also important to note that no more aircraft will fly at night than currently during any trial and that nobody will be newly overflown.
Discussions with the CAA and work by the NMB to bring the RNN to fruition continues and for a more detailed explanation about the proposed initiative, you can read our Q&A.
We have also noticed some recent speculation among local residents that a routine calibration test flight at Gatwick is a precursor to the RNN. Calibration checks of the Instrument Landing System are in fact a periodic safety requirement for all UK airports so are not linked to the proposed RNN.
The Instrument Landing System comprises of a radio beam and a signal that guides inbound aircraft to touchdown. The procedure involves making a series of approaches and breaking off without landing. This results in areas surrounding the airport being overflown during the calibration test flight. The checks are carried out at night when there is little traffic and because of this a light aircraft is used to minimise disturbance to the local community.
I will share further updates on the RNN once the initiative has been discussed at the next NMB.
NOISE MANAGEMENT BOARD