Scientific advice and evidence in emergencies - Science and Technology Committee Contents

Memorandum submitted by NATS (SAGE 09)


  1.1  NATS is the UK's leading provider of air traffic management services and we are regarded as a world leader in our industry.

  1.2  NATS was established as a PPP in 2001 and is owned 49% by the UK Government, which also maintains a Special Share; 42% by The Airline Group, a consortium of UK airlines; 5% by its employees, and 4% by BAA.

  1.3  NATS comprises two businesses. NATS (En Route) plc (NERL) is the monopoly provider of en-route air traffic services in the UK and the north east quadrant of the North Atlantic, provided under licence from, and regulated by, the Civil Aviation Authority (CAA); NATS (Services) Ltd (NSL) is NATS' non-regulated business providing air traffic services at many UK airports and is NATS' interface with the wider UK and global ATM markets.

  1.4  The terms of NERL's licence from the CAA require the company to be capable of meeting on a continuous basis any reasonable level of overall demand. NERL is charged under its licence with permitting access to airspace on the part of all users, safely whilst making the most efficient overall use of airspace.

  1.5  In other words, NATS' job is to meet the air traffic service requirements of airlines and others using UK airspace, including the Military, and to control traffic safely and efficiently. NATS does not establish airspace policy,   which is the responsibility of the Directorate of Airspace Policy (DAP) at the CAA.

  1.6  NATS welcomes the Committee's inquiry, and this opportunity to contribute answers to your questions as part of your inquiry.


  2.1.  NATS' submission to the Committee responds to the questions posed and we would be happy to provide further explanation should the Committee find that helpful. In summary, our responses make the following points:

    — The crisis was treated initially as a regulatory and ATM safety issue. As the industry and Government started to gain greater clarity on the risk it became clear that the risk was an airworthiness issue.

    — During the crisis the industry and scientific community faced a dichotomy between science and research wishing for more evidence over a prolonged period of time and industry needing immediate and innovative solutions to the issue of safe ash concentrations in which flights could operate.

    — UK coordination was generally good but constrained by the international nature of the industry. Management of any risk in the aviation industry calls for a pragmatic international approach given the cross-border nature of our business.

  2.2  In addition, we note the Committee's interest in other potential risks including solar flares. We refer briefly to the impact of solar flares which may have an impact on aviation although the risk is still being assessed.


  3.1  On the afternoon of Wednesday 14 April, NATS received an ash report from the Volcanic Ash Advisory Centre (VAAC) of the Met Office. NATS operational staff liaised with the Met Office, airlines and neighbouring ANSPs. It became clear that this would be an unprecedented and significant event.

  3.2  NATS established that the application of international guidance material as contained in the ICAO Regional Volcanic Ash contingency plan, was appropriate although it had the potential to have a widespread and significant effect in UK airspace.

  3.3  In line with emerging international consensus, and following consultation with UK national authorities, NATS issued Notices to Airmen (NOTAMs) restricting Instrument Flight Rules (IFR) clearances in controlled airspace in areas shown by the VAAC maps to be contaminated. (The Met Office provides these maps).

  3.4  The effect of the NOTAMs was that no IFR clearances could be offered in UK controlled airspace. These actions satisfied NATS' obligation to manage the air traffic network safely.

  3.5  Overnight, the VAAC chart update showed that the hazardous areas would effectively cover the whole of the UK during the following day.

  3.6  On the morning of Thursday 15 April, following discussion and review with the CAA as the Regulator, it reinforced NATS' actions by issuing its own NOTAM, also prohibiting IFR flights in controlled airspace and advising caution with Visual Flight Rules (VFR) flights.

  3.7  From that point, NATS continued to assist and consult with airport and airline customers and national authorities to ensure we could restart the national network as safely and efficiently as possible, as soon as new guidelines were issued by the CAA. We initiated regular teleconferences with all these stakeholders, plus Eurocontrol, the VAAC and other European ATM companies,

  3.8  The responses from each European State were inconsistent, some following the international guidance and others applying different procedures based on their own supplementary analysis.

  3.9  On Tuesday 20 April the CAA issued guidance to airlines permitting IFR clearances over the ash, subject to specific conditions eg flights had to guarantee they were able to land clear of the ash (refer to CAA for more detail).

  3.10  Later that day we had indications from the national authorities that fresh guidelines were likely to be issued with respect to flight in contaminated airspace. We intensified our co-ordination with customers, airports and national authorities and with European ANSPs to prepare for a co-ordinated, safe and efficient restart of operations.

  3.11  On Friday 23 April at 1,300 local, the ash contamination moved away completely from UK airspace and consequently no restrictions were imposed and there has not yet been a recurrence.

  3.12  The eruption caused the largest disruption to commercial aviation in Europe since the Second World War. As the en-route service provider in the airspace adjacent to the disruption, NATS was under intense scrutiny in the way we contributed to the management of the crisis. We continue to be closely engaged with the whole industry to develop new policies and safety rationales to cope with future disruptions.

  3.13  Throughout the crisis, NATS was heavily engaged with airlines, regulators and engine manufacturers, seeking improved operational procedures to allow flights to operate safely.


4.1  What are the potential hazards and risks and how were they identified? How prepared is/was the Government for the emergency

  4.1.1  As part of our routine risk management in 2009, NATS ensured that communications with the UK Met Office and the Regional Volcanic Ash Communication Cell (VACC) were fit for purpose. In addition our units were aware of the risk.

  4.1.2  Whilst the ICAO contingency plan was developed with most stakeholders it was not explicit in identifying where the risk lies and who should therefore manage mitigation of the risk. ICAO documentation concentrated on ensuring that information on contamination flowed to the operator in the most expeditious means possible.

  4.1.3  We believe that in balancing risk against probability, the industry had looked at the history of aviation encounters with ash and taken the view that the probability of disruption from Eyjafjalla erupting was very low level. This may help explain why there had not been a significant investment by operators or manufacturers to develop the policy with reference to volcanic eruptions beyond the generic "do not fly in visible ash" advice.

  4.1.4  The crisis was managed initially as a regulatory and ATM safety issue. As the industry and government gained greater clarity on the risk it became clear that the risk was an airworthiness issue. The owner of the risk should be the aircraft operator community and it is for them to seek mitigation with their manufacturers and to present their safety rationale to the appropriate regulator The ATM role is then to handle permitted flights safely.

  4.1.5  We believe that any risk would benefit from analysis outside the pressures of crisis. The owner of the risk should be unambiguously identified and then empowered to manage the development of mitigation. In many respects the management of Swine Flu seems to have identified the Department of Health as the risk owner and then the population was clear about who owned the problem and was accountable for the procurement of solutions.

  4.1.6  Turning to the solar flare risk, we would be keen for the Committee to ensure that the owner of any solar flare risk on Aviation is clearly identified now so that the risk can be clarified and appropriate risk based mitigations developed.

4.2  How does/did the Government use scientific advice and evidence to identify, prepare for and react to an emergency?

  NATS has no information to aid the Committee on this question.

4.3  What are the obstacles to obtaining reliable, timely scientific advice and evidence to inform policy decisions in emergencies? Has the government sufficient powers and resources to overcome the obstacles? Was there sufficient and timely scientific evidence to inform policy decisions?

  4.3.1  It seems little more than luck that the UK had not experienced such levels of aviation disruption before, given that an Icelandic volcano erupts every five to seven years on average.

  4.3.2  During the ash crisis it became apparent that whilst the existing dispersion model operated by the UK Met Office was competent, the quality and fidelity of the output was dependant on the accuracy of the inputs to the model. For this event the type of ejection being produced was critical to modelling accurately the dispersal of the ash cloud. It is clear that data of sufficient granularity was lacking although we understand that accurately establishing the density and composition of the ash is the most difficult scientific challenge.

  4.3.3  There was a continuing need during the crisis for sampling of the atmospherics to validate the model particularly around critical margins, for instance where a contamination line transits an airport or vital piece of airspace.

  4.3.4  NATS supports the review of atmospheric sampling and monitoring in order to improve the accuracy of ash maps; we believe the costs of doing this would be heavily outweighed by the financial impact on the industry of unnecessary disruption. The Committee may wish to consider the costs and benefits of a standing monitoring capability either at a UK or European level and how that might be financed.

  4.3.5  During the crisis the industry and scientific community faced a dichotomy between science and research wishing for more evidence over a prolonged period of time and industry needing immediate and innovative solutions to how safe the ash concentrations were to fly in. Over time the scientific community became more engaged in providing real time advice rather than the traditional preference to gather data for further future detailed analysis.

  4.3.6  Engine manufacturer advice was—and still is—generic with little momentum for it to be detailed and risk based, though this incident has escalated awareness of the need for a tailored solution for operators.

  4.3.7  Different engines may have different tolerances, operators may have different risk appetite and route structure and particular operations may have different exposure times. The Eyjafjalla eruption graphically demonstrated that operators cannot tolerate a "one size fits all" approach to regulation of risk management of this type.

  4.3.8  Operators can influence their manufacturers and suppliers to provide appropriate mitigations and tolerances for them to fly and to satisfy any conditions from the appropriate safety regulator. The cost of mitigation would therefore benefit from a cost benefit analysis by the part of the industry that owns the risk and would have to fund mitigation.

4.4  How effective is the strategic coordination between Government departments, public bodies, private bodies, sources of scientific advice and the research base in preparing for and reacting to emergencies?

  4.4.1  Coordination was executed through the National Airspace Crisis Management Executive which is chaired by the CAA with participation of DfT, NATS and MoD. This group had been developed over the previous 18 months to two years under the banner of Joint and Integrated ATM in the UK. It was formed to manage crises in airspace, for instance the airspace implications of a major interruption to Air Traffic Control. The DfT then acted as a conduit to the wider Government community.

  4.4.2  Whilst we were fortunate to have the body, this group had difficulty at times influencing the necessary scientific and international regulatory response. This crisis demonstrated that the UK cannot determine such policy in isolation as aviation is global and inconsistencies in regulatory application inevitably cause confusion to the public and imbalances in the route network. The reaction to a crisis in aviation immediately impacts on the wider international network, private organisations will become frustrated by inconsistencies and thus feed public dissatisfaction with the response.

  4.4.3  Prior to the crisis the role of the scientific community, principally through the UK Met Office and VACC, was to identify the areas of contamination and to ensure that airspace users were aware of the areas through regular notices and updates. This crisis has broadened the demand on these experts to place greater emphasis on forecasting and dispersion models. In addition manufacturers have had to develop their policy beyond the simple "do not fly in visible ash" to include advice on tolerance to ranges of contamination.

  4.4.4  In short, the UK coordination was good but constrained by the international nature of the industry.

4.5  How important is international coordination and how could it be strengthened?

  4.5.1  We believe that the high level owner of any risk should manage the development of any mitigation with other stakeholders, whether they are regulatory or service provision bodies. The role of the regulator is to listen to the industry and the risk owners and to understand, and if necessary approve, the mitigation proposed.

  4.5.2  Management of any risk in the aviation industry calls for a pragmatic international approach given the international nature of our business.

  4.5.3  In the specific case of volcanoes it is vital to achieve consistent international airworthiness criteria for flight in ash clouds. To do otherwise will result in airspace complexity where operators fly in accordance with an inconsistent regulatory approach creating inequality across frontiers and greater stresses on regional transport infrastructures.

  4.5.4  The ash crisis became deeply political at a European level. We believe the UK response was proportionate, but there was an issue with some of the operational decisions made in other parts of Europe.

  4.5.5  We believe that the industry would benefit from stronger central direction/regulation in Europe which is geared to practical well prepared solutions rather than political expedience. In Europe, this is the role of the European Commission, working through Eurocontrol and EASA, the new EU safety regulator. However, solutions must be orchestrated at a practical level internationally and across the industry, not on a political basis. In so doing, effective coordination must be extended beyond the EU to the ICAO European and North Atlantic regions. That in turn would feed into the global ICAO mechanism for development of global guidance and procedures.


September 2010

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