Heathrow trial of some planes using 3.2 degree approach (not 3 degrees) starts 14th September

Heathrow airport knows it has a massive problem in trying to persuade people that adding a new runway would not greatly increase the amount of noise that residents around the London area are exposed to.  So it has various ideas about how it might manage this. It is starting a trial 14th September (ending on 16th March 2016) for planes to approach the airport at an angle of 3.2 degrees, rather than the normal 3 degrees.  Heathrow says this is optional and airlines can take part if they like. They say this will only affect planes on the final approach into Heathrow (approx. 10 nautical miles from touchdown), and will be trialled on westerly and easterly arrivals. The claim is that a plane 10 miles away from touchdown would be 215 feet higher. So around Clapham a plane might be at 3,400 feet rather than at 3,185 feet. WIth less height difference near the runway. That really does not make a huge amount of difference to the noise perceived. Heathrow says planes will continue at 3.2 degrees right up to landing, though not in bad weather. However another possibility is a “2 segment” approach, where the plane levels off to 3 degrees for landing. “Even 3.2 degrees could interfere with the ability to use low power/low drag and reduced landing flap techniques.” The 3.2 degree approaches have been  used at Frankfurt and residents do not report any significant benefits.

You can apparently email the airport for more info. noise@heathrow.com

Heathrow launches steeper approach trial to reduce noise

10.8.2015 (Heathrow airport press release)

Main details here

Heathrow today announced plans to trial a steeper approach for aircraft landing at Heathrow.

This trial is one of 10 practical steps Heathrow is taking through its Blueprint for Noise Reduction to explore ways to improve the noise climate around Heathrow.  If adopted, it will be the only airport in the UK to introduce steeper approaches as a means to reduce noise on the ground.

The international standard approach for most airports in the world is set at 3 degrees, except for obstacle clearance (e.g. buildings, mountains etc.).Heathrow believes a steeper angle is possible and will lead to quieter approaches to the airport. This has been the experience at Frankfurt airport that has introduced steeper approach angles to reduce noise for people living nearby.

To test whether the implementation of steeper approaches of up to 3.5 degrees at the airport is possible, starting on 14 September 2015 Heathrow will be trialling a slightly steeper approach angle of 3.2 degrees. The trial has been approved by the Civil Aviation Authority and is planned to run until 16 March 2016.

While the trial is optional, a large number of airlines that have the necessary standard of navigational equipment for this approach are expected to take part. Steeper approaches, along with other new operating procedures, and new aircraft technology will ensure that even with expansion at the airport, fewer people around Heathrow would be affected by aircraft noise than today. This was confirmed by the Airports Commission in their recommendation to Government which stated that at least 200,000 fewer people are expected to be within Heathrow’s noise footprint by the time an additional runway opens.[Truly weasel words, with no details given – just wishful thinking probably.  If they can slightly alter the noise contours, in theory fewer people are affected. In reality the difference in noise for those inside and just outside the contours is imperceptible. Yet those just outside the contours are considered not to be affected by plane noise. Clearly an unacceptable way to judge how many people are affected].

Matt Gorman, Heathrow Director of Sustainability and Environment said:

“Heathrow has changed, and taken a new approach to addressing our impacts on communities, including when it comes to noise. Our Blueprint to cut aircraft noise have been driven by feedback from local communities.  It role is to challenge the industry to think innovatively about ways to reduce noise. [Anything other than not expanding and not adding thousands more flights per year].

Steeper approaches are just one step in the right direction, and along with other quieter operating procedures and incentives to bring quieter aircraft into operation, will ensure fewer people are affected by noise, even with an expanded airport.”

Heathrow has briefed a range of stakeholders about the trial including the Heathrow Airport Consultative Committee and Community Noise forum.  Mobile noise monitors have been specially deployed for the duration of the trial.  A report will be issued following the trial summarising the findings.

Residents around the airport wishing to learn more about the trial are encouraged to contact our Community Relations Team at 0800 344 844  or email noise@heathrow.com


The trial only affects arriving aircraft on the final approach into Heathrow (approx. 10 miles from touchdown).  It will be used on all four runway approaches (27R, 27L, 09R, 09L).

For more information, please visit http://www.heathrow.com/noise/heathrow-operations/latest-news


Heathrow to trial steeper approach angles in a bid to cut noise

10.8.2015 (Telegraph)

By Ben Martin
The airport hopes to overcome objections to a third runway, which include worries about aviation noise


Heathrow is to start testing steeper angles of aircraft approach in a bid to tackle the blight of aviation noise on local communities, a problem that is one of the main obstacles to expanding the airport .

Jets currently glide into Heathrow at a 3 degree angle, which is the international standard for the majority of airports. Heathrow will start a six-month trial in mid-September that will see planes come in at 3.2 degrees, a sharper angle that it hopes will lessen the roar heard by residents living within the final 10-mile approach.

The government-appointed Airports Commission concluded last month that building a third runway at Heathrow offered the best solution to tackling Britain’s aviation capacity crisis.

Ministers must now decide whether to press ahead with the commission’s recommendation and are weighing-up objections to Heathrow expansion. The din caused by aircraft and worries about increased air pollution are among the biggest concerns raised by opponents of a third runway .

Introducing a 3.5 degree angle of approach was among the noise reduction measures that Heathrow included in its successful submission to the commission for expansion. Separately, adopting a steeper angle was also one of 10 measures that formed part of the noise reduction “blueprint” that Heathrow published last December.

Frankfurt, one of Heathrow’s main rivals, has already implemented sharper approach angles in an effort to relieve local residents from the roar caused by planes (Other OTC: UBGXF – news) .



Heathrow’s website says:

Efforts to reduce the impact of aircraft noise on local communities do not depend simply on improvements in technology. How and where aircraft are flown can also make a significant difference.

There are three broad categories of operating procedures that can reduce noise:

  • Making individual planes quieter, for example by changing the thrust settings
  • Planes flying higher and therefore quieter, using steeper approaches for example
  • Routing planes differently, such as runway alternation.

Steeper approaches graphic

We are committed to working with the CAA, NATS and airlines to explore and employ smarter operating procedures to reduce the noise impact of aircraft on residents.

In particular we will:

  • take full advantage of opportunities to manage airspace differently, working with local communities to identify changes that could benefit them. We will continue to trial new airspace management procedures to test the concept of providing predictable periods of respite from early morning arrivals and for some of our departure routes. We will review the results with a view to introducing the changes permanently if communities value them and they are operationally feasible
  • take steps to better understand the noise and operational impacts of ending the practice of ‘westerly preference’ through a study we have commissioned from NATS; and
  • propose a significant increase in fines for aircraft that exceed the airport’s departure noise limits at night and invest the funds in local community projects.



The CAA document “Managing Aviation Noise” (2014) says:


Slightly steeper approach

The international standard Instrument Landing System (ILS) glide path angle is 3 degrees. Increasing an aircraft’s glide path reduces noise in two ways. Firstly, it increases the height of the aircraft over the ground, increasing the distance over which sound travels before it reaches a population. Secondly, it increases an aircraft’s rate of descent, reducing the amount of engine power required, reducing the amount of noise emitted.
Some airports in the UK already utilise glide path angles greater than 3 degrees to account for obstacles preventing the standard 3 degree flight path being adopted.
Category III ILS systems that provide the highest capability to land in poor visibility are limited to angles of 3.25 degrees. Above 3.49 degrees ILS are limited to CAT I, offering less capability than CAT II or CAT III systems. For most airports, the ability to continue operations in low-visibility condition is a key requirement that would dissuade it from adopting approach angles of greater than 3.25 degrees.
In addition, ICAO currently urges States not to adopted flight path angles greater than 3 degrees for environmental reasons. Frankfurt airport’s new runway, 07L-25R is required to have two ILS to enhance operational resilience. Since the existing ILS was already CAT III, the airport in addition installed a CAT I system at 3.2 degrees.
Both systems operate simultaneously. In low-visibility operations, the CAT III 3 degree system is used, however, when conditions are appropriate, aircraft are directed to use the 3.2 degree system.
Heathrow 3.2 degrees
It is clear that the additional benefits of 3.2 degree approaches are relatively small, though it must be recognised that this procedure is not used at any airport (except where obstacles dictate) so benefits could accrue across a large proportion of operations at many airports (excluding operations in low-visibility).
However, it likely that even 3.2 degrees could interfere with the ability to use low power/low drag and reduced landing flap techniques.
It is therefore recommended that industry consider the potential for slightly steeper approaches to impact on existing practices such as low-power/ low-drag and reduced landing flap techniques as part of consideration of adopting this procedure where appropriate to mitigate noise.
The aviation industry should consider the potential for slightly steeper and reduced landing flap techniques as part of consideration of adopting this procedure where appropriate to mitigate noise.

Two-segment approach

Because of the issues highlighted above in relation to the use of a slightly steeper approach all the way to touchdown, an alternative concept referred to as the two-segment approach is being actively considered as an alternative means to reduce arrival noise.
A two-segment approach adopts a much an intermediate approach phase flown at a steeper angle, before transitioning back to a standard 3 degree approach. This would potentially provide noise benefits further out during the approach phase, without affecting the final approach phase.
During the past twelve months British Airways has provided flight simulator access and worked with the CAA to address and consider issues associated with the concept, including: ƒ
– Technical feasibility – can such a procedure be flown safely by all types? ƒ
– Environmental benefits – what is the magnitude of the benefits achievable whilst ensuring operations remain safe? ƒ
– Airport capacity impact – what impact might it have on airport capacity? ƒ
– Scalability – could it be deployed only at certain times of day and what might the training and oversight requirements be?
The CAA recognises the need for industry engagement to address these issues and welcomes British Airways’ commitment and resources to research this concept. Because of the much greater uncertainty and lack of maturity associated with the concept, it is not possible to illustrate potential noise benefits at this time.
However, the fact that during the steep intermediate segment, an aircraft would be higher and at lower power than during a slightly steeper approach, the noise benefits would be expected to be greater than for a slightly steeper approach.
The CAA will continue to focus on exploring the potential for two segment approaches, and seek aviation industry support in order to realise the potential for this concept to significantly reduce approach noise.
CAP 1165 | Managing Aviation Noise 44 Chapter 5:


HACAN said, about possible steeper approaches (14.6.2014):

Heathrow: A mixture of steeper landing approaches, displaced landing thresholds (where aircraft touch down 700 metres further along the runway) and new flights paths brought in to avoid the most populated areas will cut noise levels.

CAA:  The CAA stresses that only a marginally steeper approach – 3.25 degrees rather than the current 3 degrees – is possible, and that even 3.25 might cause problems in low-visibility.  At Frankfurt 3.2 degrees is used but it reverts to 3 degrees at times of poor visibility.  Although a steeper descent approach would mean planes remain higher for longer, it concludes “the additional benefits of 3.2 degree approaches are relatively small.”   Link

Atkins:  The Atkins Report doesn’t analyse the feasibility of a steeper approach, nor does it comment on the impact of displaced landing thresholds; it simply assumed both will be in place when it made its calculations of the total number of people likely to be impacted by a 3rd runway would be over 1 million.

Neither the CAA nor Atkins assesses Heathrow’s claims the “new flight paths will avoid the most populated areas.”   Partly this is because Heathrow has not yet published these new flight paths but probably also due to the recognition that altering flight paths will have a minimal overall impact since all of London is so heavily populated.  Moreover, as Atkins points out London’s overall population is likely to have increased significantly by 2026.

Verdict: Steeper approach paths might reduce noise but the impact would be “relatively small”. There would be benefits from displaced landing thresholds (aircraft touching down further along the runway). Given the density of the London population – and the fact that the number of people living in London is expected to increase – it will be difficult to find “less populated” areas over which flight paths could be routed.

Reality Check:  star_tinystar_tiny