Gatwick Obviously

e-newsletter No.31

An airline Captain speaks ...

An airline Captain with extensive experience of flying into Gatwick has bravely been in touch. Understandably he wishes to remain anonymous - for now. A slightly edited copy of a letter he has written to the CAA is reproduced below, with his permission.

We also reproduce the letter he received from the CAA, which many of you will also have received.

(Should anyone doubt our pilot's veracity, we can put you in touch with our lawyers).

I will try and summarise the message in this long newsletter as follows:

If the CAA want to reduce risk and increase safety in terms of the arrivals airspace, they must look at the core reason for the Go-arounds - excessive use of the runway and inadequate spacing between aircraft.

To use 'unstable approaches' per se as the root of all evil is simply wrong.

But don't listen to me, I'm just someone trying to change government policy and resist the imposition of noise ghettos across the land.

If you haven't much time, please just read what our pilot has to say and jump my introduction. We've highlighted it in blue for quick scrolling to on your smart phones.


It seems we are all being impaled on the spear of Gatwick's avarice.

Here's why:

The CAA say that the arrivals swathe has been narrowed by 60% and moved eastwards to reduce Go-arounds (GAs) caused by 'unstable approaches'.

This narrowing (plus incredibly low altitudes and the easyJet whine) has resulted in misery for countless thousands across West Kent, East Sussex and further afield.

However the statistics show that the very significant majority of GAs are due to the runway being occupied by another aircraft, rather than to unstable approaches.
(In 2014 there were 212 Go-arounds caused by 'runway occupied' and 102 by 'unstable approaches' - Source: Gatwick Flight Performance Team)

If it is true that the reason for the moving the ILS interception point from 10 to 12 miles from touchdown was to reduce 'unstable approaches', the fault clearly and undeniably lies with inadequate spacing between aircraft, whether on final approach or on the runway, and in turn excessive use of the runway i.e. above the runway capacity which is acceptable when such GAs occur. There is a simple solution to this problem and therefore one which the CAA as regulator should require. It is for Air Traffic Control to be less ambitious, for them not to try to maximise the utilisation of the runway to a point which causes GAs, and not to increase the runway use to a point where GAs are inevitable or even likely, with consequential increased risk and lowering of standards of safety, a consequence which is indeed recognised by the CAA

If the number of GAs is excessive, as the CAA clearly imply, those advising the CAA clearly believe something needs to be done. However, the problem of GAs and increased risk would not be solved or assisted but would, in fact, paradoxically be compounded by lengthening the distance between the ILS interception point and touchdown. This is because the longer distance on final approach - and therefore time before touchdown - by an aircraft from the ILS interception point gives encouragement to Air Traffic Service providers to seek to increase the maximum runway utilisation yet further, in the belief that more time before touchdown is available to ATC or aircraft on final approach to sort out the problem of inadequate spacing, a problem which is caused by ATC, not the aircraft or its crew.

Consequently, moving the interception point from 10 to 12 miles increases the pressure on the ATC controllers to increase yet further the runway utilisation, not to diminish, let alone solve, the GA problem.

The CAA wish to see safety increased and nobody could possibly argue with that. They cite the need to lessen the number of GAs as an objective. That too cannot be doubted as an objective. Unfortunately, the approach that those concerned including the CAA has adopted, no doubt as a result of persuasive submissions by NATS and Gatwick Airport Limited, does not tackle the root problem.

The number and proportion of GAs can only be lowered if the causes for a GA to be required is diminished. This in turn, from consideration of the GA data, can only be done by lowering the utilisation of the runway, as the cause for the clear majority of GAs relates directly to its over-utilisation.

It is to be noted that NATS and Gatwick Airport limited have in the recent past been proud of the increase in maximum capacity of the runway. Press reports have been prevalent on the subject. This has not only had the effect of increasing the potential for the number of GAs, but this can only occur at the cost of increased noise to those residents who suffer on the ground by 'vectoring decisions' in moving the minimum ILS interception point so as to accommodate such increased numbers, without any form of consultation let alone compensation.

This change has been imposed on them in effect by the airport operator, who could easily agree to accept a lower runway utilisation, consequentially fewer GAs and not having to require the moving of the ILS interception point. This is not merely unfair but unacceptable, as the CAA must agree.
The aviation industry has a responsibility to be a good neighbour.

The Government's first policy aim concerning noise in England is to avoid significant adverse noise impacts on health and quality of life. The CAA is duty bound to have regard to this policy. This is patently not being done. It is claimed that by adopting a concentrated flight path, this limits the number of people significantly affected by aircraft noise. It does nothing of the sort. It significantly increases the number of persons significantly, and indeed unacceptably, affected by aircraft noise. That is clearly to act contrary to government policy objective.

I would like to finish with three further comments on statistics.

  1. In her letter below, Dame Deirdre Hutton, CBE, Chair of the CAA states, as if it were proof of her policy, that 'As a percentage of all Go-Arounds [caused by unstable approach] the improvement since 2011 is even starker'

    Wrong data used in the wrong way to support a wrong policy.

    She is using the 'runway occupied' figure (see all reasons for such above) as the relative benchmark. So the more organised chaos there is on the Tarmac, with aircraft all over the place, the greater the proportional difference she can demonstrate in GA's caused by unstable approaches!

    As we demonstrated in the last newsletter, the difference versus actual flight numbers is the true benchmark.

    For the calendar years 2011 (100 GAs caused by 'unstable approaches') and 2014 (103 ditto) the proportional difference was four ten-thousandths of a percentage point.

    For all this pain.

  2. Given that Go-arounds and 'unstable approaches' are now known to be blamed for our misery, we have been looking closely at the data in the public domain. These tables below are from the Flight Performance Team on Gatwick's website. Given that there is no room for statistical inaccuracy in aviation in terms of safety (and given that these figures are seemingly SO relevant to our wellbeing on the ground), why do the figures for 2008 and 2009 suddenly drop? (Ignore 2010, the year was incomplete at the time of the reports). I also note that in 2008 despite suddenly reducing the amount of Go-arounds, as a % of arrivals they went up? These stats are not a one-off blip and remain in place for every report since.

    What about the current data on Go-arounds? Is it 100% accurate? Is Dame Deirdre being fed duff information upon which basis our skies are being wrought asunder?

    How can we have confidence in the stats?

    gon_230615_01.gif gon_230615_02.gif

    Q3 2010

    Q4 2010

  3. In that last newsletter I quoted complaints into Gatwick alone increasing over 500% for 2014 figures over 2011.
    The figure for 2013 v 2014 (pre-narrowing 2,829 v post narrowing 25,440) is 'even starker' at 899.25%.

    We never exaggerate in these newsletters - we don't need to.

    Martin Barraud

    The Captain's Letter
    (My bold)

    Dear Dame Deirdre

    Thank you very much for your reply to my e-mail. Please do not apologise for the delay in replying as these matters are complex.

    However, your reply unfortunately discloses a failure to consider the basic facts and data underlying the matter, as no doubt these have not been brought to your attention by those advising you.

    Much of your letter concerns safety. There are a number of points in your letter which raise matters which require to be challenged. As a former airline pilot and training captain, I have been involved with all aspects of flight safety for the last 38 years. It does give me a good insight into the validity of some of the assumptions made by those advising you on matters within my professional knowledge. I hope that you will therefore give this particular weight when considering the points I make below.

    I must comment on your statement that rushed approaches cause accidents.

    Your assertion that there have been a number of accidents (the figure generally quoted is 40% of all approach and landing accidents) caused by unstable approaches requires qualification. Having studied such matters in some detail, it is apparent that the predominant reason for such accidents is generally that the crew failed to perform a go-around from an unstable approach and made a poor decision to continue to a landing. In the airline I was involved with there were 'gates' for speed, altitude, vertical speed, thrust setting, aircraft path and aircraft configuration. If these gates were not achieved a go-around was mandatory. It is a cause for real concern if crews are not going around from unstable approaches. There should always be go-arounds from unstable approaches, and there should never be an accident.

    It would be more profitable to address the multitude of reasons for rushed approaches than the minor point of where the interception point is on the approach.

    There can of course be a crew factor but this is generally with improperly trained pilots adopting improper operating procedures, often in older aircraft. They should not be at Gatwick at all and strong regulatory measures should be taken with airlines who constantly infringe stated procedures and whose pilots are improperly trained. You must know who the culprits are.

    You mentioned, at length, the role of ATC in causing rushed and unstable approaches. You give a list of inappropriate ATC actions such as poor vectoring, speed control, distance information, etc., to which the only response is why not get it right? If ATC cannot handle the amount of traffic successfully then those responsible, whether the airport or the ATS provider should reduce the numbers of aircraft using the single runway so they can!

    I would ask that you personally examine the raw data concerning aircraft approaches at Gatwick and in particular the reasons given for GAs (Go-Arounds). The evidence which is available to all UK airport operators and ATS providers must give the reasons for each GA, as stated by the relevant person responsible, whether the pilot or ATC controller. This clearly shows that the majority of GAs is due to the runway being occupied, either by an aircraft taking off or by an aircraft not clearing the runway after landing. This is an ATC problem, not due to the crew of landing aircraft having to abort due to an unstable approach or for other reasons including weather.

    You will now find from a close study of the data that the majority of GA problems (both blocked runways and rushed approaches) occur because ATC controllers are under pressure from their Air Traffic Service Provider employer and the airport operator to maximise the use of the runway, as this leads to maximisation of utilisation of the airport, productivity bonuses and profits for the airport. However, by doing so, and on the basis of what you have said yourself, this clearly produces a compromise of safety. You should, with respect, regard this as totally unacceptable management pressure, but nothing is being done by the CAA to reduce this cause of GAs, as far as I am aware.

    There is a need for ATC at major single-runway airports such as Gatwick, where the runway capacity is approaching its maximum, to be less ambitious and not to try to cram extra aircraft movements onto what is clearly a single runway with an inadequate capacity. These go-arounds have nothing to do with where the aircraft intercepts the final approach. It is to do with maximisation and over-use of the runway above its proper maximum capacity.

    Government policy, as you know, is to make best use of runways and infrastructure at UK airports, not to maximise their use whatever the proper and safe (i.e. "best") capacity is or should be.
    This is an often-misquoted important part of the Government's policy for airports.

    Excessive use of the capacity of a runway leading to GAs is far worse than under-utilisation, as it leads to increased risk and can, as you recognise, lead to dangerous, indeed unacceptable, consequences.

    The importance of this message is, put bluntly if I may, for you to consider the statistics carefully and then to take action to sort out the problem. I ask that you consider the raw data personally, as I have done. When you do so, you will see that it discloses a clear majority of GAs are due to commercial pressures. There is, as I have said, an easy remedy - for ATC to ensure that there is adequate spacing between aircraft. That must surely be the first imperative for the airport operator, the ATS provider and the CAA.

    My original e-mail was prompted by the changes to the approach procedures where the noise of aircraft approaching runway 26L at Gatwick is now concentrated in a narrow corridor, the vast majority of aircraft intercepting the ILS between 10 and 12 n.m out. This has resulted in an intolerable increase in noise because of a change in flight path, which has been imposed upon us residents by the airport and those who operate it. The real reason for the change is sadly obvious - profit for the airport - and safety is being used as the excuse.

    The aviation industry has a responsibility to be a good neighbour. We have developed numerous techniques for alleviating noise nuisance such as noise abatement take-offs and continuous descent approaches. Steeper approaches and GBAS approaches are being considered. It should be possible to vector aircraft onto the final approach at different points quite safely, whether by ATC controllers or automated systems, if ATC and pilot procedures are robust.

    The noise nuisance would, therefore, be shared more equitably over a wide area as before, which, at present, it is not.

    Your final sentence states "SAFETY WILL ALWAYS BE OUR, AND THE AVIATION INDUSTRY'S PRIMARY OBJECTIVE" If safety is as important as you say (and we all agree it is), will you address the real safety issues caused by the commercial pressures outlined above?
    You are the regulator!

    Yours sincerely

    [An airline Captain with extensive experience of flying into Gatwick]

    Dame Deirdre Hutton

    Chair, Civil Aviation Authority
    45-59 Kingsway,
    London WC2B 6TE

    Tel: 020 7453 6003

    Dear xxxxxxxxxxxxxxx

    Thank you for your email of XXXXXXX regarding aircraft approach paths into Gatwick and I am sorry for the delay in my reply.

    As you will be aware, there are many causes of go-arounds and the change in NATS’ operational procedures that has moved the final approach interception point was introduced to minimise just one of these, i.e. the potential for air traffic control induced rushed and potentially unstable approaches, which may result in a go-around.  Unstable approaches have been identified internationally as a pre-cursor event to runway excursions and a causal factor in a number of accidents worldwide.

    Aircraft must meet certain criteria on approach to be able to land safely, and managing an aircraft during the descent and approach phases essentially becomes a task of energy management. Landing long, or landing at excessive speeds, can result in a runway excursion and excessive sink rates or failure to capture the correct vertical profile can contribute to hard landings or Controlled Flight into Terrain (CFIT).  In a de-stabilised approach, the rapidly changing and abnormal condition of the aircraft may lead to loss of control.

    Such loss of control events can have fatal consequences, hence the desire to eradicate them. They can occur for many reasons, but one of those causal factors can be the vectoring decisions made by air traffic controllers.

    Inappropriate Air Traffic Control (ATC) actions can contribute to a stable approach becoming unstable due to the following:

    • Distance (Time) provision where insufficient track miles are provided for the flight crew to achieve the correct vertical profile and/or aircraft energy during descent;
    • Changes of runway can increase flight deck workload and can significantly affect track mileage to touchdown and may not allow sufficient time for the crew to re-plan the approach;
    • Changes in the type of approach can affect the planned descent profile.
    • Inappropriate vectoring that does not allow the correct descent profile to be flown in relation to the Instrument Landing System (ILS), and vectoring which causes the aircraft to intercept the glide path before the localiser[1]. Most aircraft will not lock onto the glidepath in this condition, causing the aircraft to 'fly through' the glide path;
    • Incorrecttrack distance to touchdown resulting in flight crew being unable to calculate their descent and speed profile;
    • Inappropriateuse of speed control which adversely affects the crew's capability to manage the aircraft’s energy and its descent profile.

    There have been a number of worldwide incidents that have led to crashes and fatalities where unstabilised approaches were the main cause. One of the actions we take to minimise such events in both the UK and Europe is to work with industry to help them ensure that aircraft arrive at final approach at the correct speed and in the correct configuration. The altitude of the aircraft is managed in a controlled manner to ensure that it is not unsafe and while service providers such as NATS try to minimise noise by applying continuous descent techniques, aircraft still have to be at approximately 3000 feet by 10 nautical miles from the airport in order to intercept the glidepath in a safe and controlled fashion. This is why (in tandem with many of our international partners) we have published safety notices to service providers about how they should vector aircraft to minimise the probability of Air Traffic Control action contributing to such events.

    Europe, and specifically the UK, has a good safety record and this is partly due to us being proactive, working with those we regulate and our international partners to analyse data that might provide clues about future risks to the travelling public. The change to NATS' operational procedures was conceived as a response to a Europe wide safety initiative known as the European Runway Safety Initiative; and measures designed to enhance runway safety that were agreed as part of the European Action Plan for the Prevention of Runway Excursions (EAPPRE).

    We have undertaken some analysis of go-arounds at Gatwick, and we have found that over the last year, despite an increase of approximately 5000 arriving aircraft, the percentage of Go- Arounds (GA) due to unstable approaches decreased both as a percentage of all arrivals (0.06%) but also in absolute numbers, reducing from 110 in 2013/14, to 81 in 2014/15.


    As a percentage of all Go-Arounds the improvement since 2011 is even starker.


    While it is correct that at certain airports, the runway being occupied by another aircraft or a vehicle is the cause of a significant proportion of go-arounds, as air traffic increases then the absolute number of go-arounds will increase unless efforts continue to reduce the instances of all the causes of them. Safety will always be our and the aviation industry's, primary objective.

    Yours sincerely

    Deirdre Hutton

    June 23rd 2015

    This newsletter goes out to well over 2,000 people on our database which grows by the day. Consequently, this may mean that it ends up in your "spam", as our first newsletter did for some. Please be sure to mark up anything from us as "not spam" to prevent that.
    You can view all our Newsletters in your web browser here: 

    Unsubscribe me from this list

    View this mailing in your web browser