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

Memorandum submitted by the Institution of Mechanical Engineers (SAGE 15)

  1.  The Institution of Mechanical Engineers is the fastest growing engineering institution in the UK, with a membership of over 90,000 professional engineers in the UK and overseas. As a Learned Society the Institution is committed to providing impartial engineering perspectives on a wide range of topics, from transport systems, an engineering response to climate change, education and critical skills, to energy production and distribution.

  The answers to the questions below refer specifically to the Icelandic volcanic ash eruptions in spring 2010.

What are the potential hazards and risks and how were they identified?

  2.  The hazards of aircraft flying into volcanic ash are, at the extreme, potential damage to critical airframe surfaces and systems and potential loss of engine power leading to crashing of the plane. At medium ash densities, there can still be damage to engines and airframe causing economic loss but at very low ash densities, there is no hazard or risk. These hazards have been identified from past flying experience where 126 incidents have been reported over the 55 years of jet engine travel. Unfortunately no quantitative demarcations have been established between the high, medium and low levels of ash density that allow us to be certain of the safety risks in each actual volcanic eruption.

How prepared is/was the Government for the emergency?

  3.  The Government was very well prepared in the sense in that it had a clearly defined regulatory body (the Civil Aviation Authority) and a clearly agreed international safety procedure (of zero tolerance to exposure to atmospheric ash) that controlled the UK response to the risk.

  4.  The circumstances leading to the closure of European airspace were therefore predictable but unprecedented. The new and unique conditions that prevailed consisted of a very large and energetic volcanic eruption which caused ash to be ejected to high altitudes in the atmosphere coupled with sustained wind directions which carried it over Ireland, the UK and Western Europe.

  5.  It is arguable that the consequences of the closure of airspace should have been considered prior to the event through scenario planning and thereby contingencies being better organised. For example, an important consequence of the closure of airspace was the stranding of UK citizens abroad. The solution chosen appeared to be ad hoc, uncoordinated and largely dependent on the differing reactions of the individual airlines concerned. As the closures stayed in place for longer then the consequences on the UK economy became multiplied. The situation confirmed the role important of international air transport as a facilitator of the economy and greater consideration should now be given to future possible disruptions.

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?

  6.  The time needed to collect new data is much greater than that available as the economic and social consequences of an airspace closure develop. The advice and evidence therefore need to be those available prior to the event. The Government has powers to ensure the quality of that prior data through the regulator (the Civil Aviation Authority).

  7.  The difficulty is with the infrequency of the risk in UK controlled airspace. The best data is obtained from real life field measurements which by definition are rarely possible. The opportunities until now have always been in overseas jurisdictions. In common with many other low probability, high consequence, risks International sharing of experience is essential to maximise the understanding of these rare events.

  8.  The sufficiency of the powers therefore relates to the ability of the UK Government to influence others overseas to collect data as the opportunities arise. These opportunities generally have not been taken to date as another, easier, cheaper, option has been to avoid flying through the ash clouds at all.

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?

  9.  The Government has a role in bringing together the various parties which are responsible for informing this decision and it appears that this role was discharged during the volcanic ash event. It appears that this coordination (between the regulator, the operators and the manufacturers) was extensive and effective notwithstanding the International limitations expressed above. However, there was a lack of background data and hence understanding of three key issues:

    (a) The amount and type of ash actually present in the controlled air space.

    (b) The sensitivity of different aircraft and engine types and flight paths to the ash cloud.

    (c) The process necessary to balance the unknown safety risks with the social and economic costs of a flight ban.

  10.  As the element of risk could not be quantitatively assessed, a high degree of caution was properly exercised. However, we consider there should have been more open engagement on the risks by various public agencies during the crisis, both with the learned institutions and especially with communication with the public at large. Arguably, inadequate quantitative demarcation of the hazards, together with insufficiently accurate and timely scientific measurement and forecasting of the density, composition and position of the ash clouds, were significant obstacles to more effective policy decisions.

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

  11.  In 1991 the aviation industry decided to set up Volcanic Ash Advisory Centres (VAACs), one for each of nine regions of the world, acting as liaisons between meteorologists, volcanologists, and the aviation industry. The UK and Western Europe is covered by a VAAC embedded in the Meteorological Office. There is therefore in existence extremely good framework for international collaboration for the interaction between volcanic ash and air operations, possibly because air transport is an international activity. An alternative safety solution however (zero tolerance) has been applied because it was effective in the overseas territories. There was no motivation amongst our partners to solve a problem of flying through ash clouds when it has not been necessary to do so until now. This latest episode gives impetus to using the current framework to create and share data on exposure.

Professor Roderick A Smith, FREng, ScD

Deputy President Institution of Mechanical Engineers

13 September 2010

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