Volcanic ash cloud paralyzes swath of European airspace

 - April 30, 2010, 4:04 AM
Many business aircraft were able to escape Europe before airspace was closed by the volcanic ash cloud on April 15. But some did not, including operators who had to keep their aircraft grounded at the London-area Farnborough Airport. Shown here are jets parked on the ramp and taxiway alongside the hangars and terminal operated by Tag Aviation. Authorities reopened British airspace at 10 p.m. on April 20.

Ash from a volcano in Iceland brought disruption to European air transport last month on a scale that far exceeded the combined efforts of global terrorism and the financial crisis. Huge swaths of the continent’s airspace were closed for prolonged periods and hundreds of thousands of travelers were stranded at various points around the world for days on end.

Business aviation, though generally hailed as the traveler’s flexible friend, also was just about brought to its knees in Europe. Due to the sheer unpredictability and complexity of airspace access rules, bizjets and even pistons were able to make only limited use of opportunities to conduct VFR flights in low-level, uncontrolled airspace (see box on page 36). Helicopters found themselves constrained too, but were able to conduct some flights to assist stranded travelers.

Almost a week into the emergency, a core tension emerged between the understandable caution of technical experts anxious to avoid allowing potentially unsafe flying and the seemingly more pragmatic approach of political leaders desperate to end the social and economic paralysis. On April 20, Europe’s consensus on its response to the volcanic eruption started to fragment when individual states began to waive restrictions that had previously been enforced at a federal level.

There was a significant breakthrough late in the evening of April 20 when UK authorities suddenly announced the immediate reopening of British airspace. The UK had appeared to be taking the hardest line on the closure of airspace but appeared to have come under intense commercial and political pressure to adopt a more pragmatic approach. Along with other European authorities, the UK Civil Aviation Authority and National Air Traffic Services had feverishly reviewed the latest technical input from engine manufacturers (see below) and from test flights conducted on April 17 and 18.

The revised advice was that operators would be able to fly through low-density ash, subject to completing engine checks after each flight. The change of position may
also have been influenced by meteorological forecasts that envisioned a shift in wind direction to move the ash cloud northward beginning April 22.

Aircraft operators were given just a few hours’ notice of the impending shutdown at noon UK time on April 15, but many were able to take decisive action in fleeing airports in the UK, which were among the first to be affected. One NetJets Europe jet took off from London Luton Airport carrying passengers with just 30 seconds to spare before the noon deadline took effect. NetJets reported a sudden surge in fractional ownership sales inquiries following the airspace closure.

In the initial couple of days after airspace was closed, other business aircraft were repositioned by flying below 2,000 feet in VFR conditions. But this approach was not successful in all cases, especially when French air traffic controllers unilaterally blocked access to VFR flights even though conditions were clear.

UK helicopter charter operator PremiAir tried to position aircraft at Calais on the north coast of France to bring home UK-bound travelers. But stultifying French officialdom soon put a stop to this initiative, as it did to efforts by private boats to rescue stranded passengers. PremiAir and other helicopter operators were able to fly to Ireland, in some cases to allow North American passengers to catch onward scheduled flights back home.

Farther afield in Russia and India, other bureaucrats also put the rule-book ahead of humanity and common sense. In Moscow, passengers who had inadvertently been trapped by cancelled flights were confined to an airport hotel under police guard because they hadn’t had the foresight to secure a visa for a country they had never planned to visit. In India, officials turned back visa-less passengers trying to fly home from other Asian countries who simply needed to be able to transfer to a connecting flight.

There have been villains in the private sector too. Several hotels around London’s Luton and Stansted airports raised prices two or three times above their highest posted rates to exploit the misfortune of trapped business aircraft aircrew.

Many FBOs found themselves accommodating stranded business aircraft and could do little but start preparing invoices for extended parking fees. There was some room for maneuvering, with Ocean Sky at Prestwick Airport in Scotland negotiating directly with the UK’s National Air Traffic Services to exploit any windows of opportunity to keep flights coming in and out. London-area Oxford Airport was on standby to remain open for 48 hours nonstop upon the reopening of airspace to be as available as possible for traffic returning
to the UK.

Commercially, the hardest hit were charter operators. At press time, most of them had done virtually no paid work for almost a week and, in some cases, they or the aircraft owners they represent were left to fret about how they would meet the next lease payments and other fixed costs.

Charter broker Hunt & Palmer said that the executive/private charter sector was on a high state of alert ready to respond to a massive influx of demand for flights as soon as airspace opened. Neil Harvey, the company’s executive charter director, told AIN that many operators had tried to keep flying during the days when airspace use was most heavily restricted but had been constrained by ambiguous guidance from aviation authorities. For example, the UK Civil Aviation Authority told operators that flights could be made following a risk assessment to establish that it would be safe to make a given flight. However, no guidance was given as to the criteria to be met in these risk assessments.

The hardest-hit areas have been the UK, Scandinavia, Germany, the Netherlands, Belgium and France. Surrounding countries such as Switzerland, Austria, Italy, the Czech Republic, Poland and other central and eastern European states suffered partial and temporary closures.

A Slow Return to Normal
Some respite came on the morning of April 20 when, following an urgent political intervention by the European Union transport ministers, Eurocontrol was given the authority to restrict operations somewhat more flexibly. Flying was permitted above 20,000 feet, making en route overflights of Europe more feasible. However, hopes of a more widespread resolution to the crisis were dashed when new ash clouds spewed from the volcano. This meant that flights continued to be banned altogether, or were heavily restricted in Denmark, Estonia, Finland, northern France, northern Italy, Latvia, Slovenia, Slovakia, Ukraine and the UK.

Spain, Portugal and southern Italy quickly emerged as bridgeheads for flights wanting to get passengers onto the European mainland. For example, German Chancellor Angela Merkel returned from a trip to Canada via Lisbon and Rome before having to resort to a long car journey north to Berlin.

Meanwhile, NBAA and EBAA indicated that they intend to proceed with the Ebace show, which is due to open in Geneva on May 4.   

Lack of Clear ICAO Policy Undermines Industry

The International Civil Aviation Organization (ICAO) has acknowledged that it urgently needs to issue precise policy on how and when it is safe for aircraft to fly in airspace contaminated by volcanic ash. Raymond Benjamin, secretary general of the United Nations-backed body, said that he will urgently convene industry experts and scientists to start drafting clear guidelines for dealing with future volcanic eruptions.

ICAO has in fact taken some significant initiatives already, but these relate only to how to inform operators about volcanic activity, rather than how they should respond to it when it affects airspace for prolonged periods. Following the June 1982 incident where a British Airways Boeing 747 lost power after flying through a volcanic ash cloud over Indonesia and descended 25,000 feet before the crew was
able to relight the engines, ICAO’s Air Navigation Commission established a set of guidelines to assist governments in the rapid dissemination of volcanic-ash-event warnings.

Initially, this comprised recommended practices and procedures covering the observation and reporting of volcanic activity, the issuance of warnings and, if necessary, information regarding the closure of air routes and the activation of contingency routes, and provided the initial structure for ICAO’s International Airways Volcano Watch.

In cooperation with the World Meteorological Organization, the organization saw the establishment of nine Volcanic Ash Advisory Centres around the world, including the one in London, which coordinated this most recent event and issued updated reports every six hours. That information was provided to states and civil aviation authorities, which then decided on opening or closing the airspace
or part of the airspace, based on modeling and weather patterns.

From 1953–when ICAO began keeping records of aircraft damaged by volcanic ash–through 2008, the organization received reports of 89 such incidents, mainly individual encounters. Before the crisis last month, never before had the agency encountered such a widespread cloud positioned across some
of the world’s busiest air routes.

“This one is unprecedented,” said ICAO spokesman Denis Chagnon describing last month’s Eyjafjallajökull eruption in Iceland. “It’s never happened before, so with IATA and others we believe once this is over, there will be a lot of lessons learned in what we do to make sure that if and when this happens again, we try to minimize the economic impact of closing down the airspace while doing it always in a safe manner.”

The agency’s stated goals are to safely minimize the re-routing of aircraft, while at the same time minimizing aircraft exposure to volcanic ash, but as Chagnon acknowledged, currently there is little consensus as to how much exposure is too much. “At the moment there is no identified definition or threshold for safe operation in a volcanic ash cloud,” he told AIN. “It’s a scientific issue; it’s also an operational issue with altitude and the composition of the volcanic ash, so it’s been difficult for engine manufacturers and the scientific community to come up with a standard such as what we have for CO2 and NOx for engines.”

While this incident will no doubt stand as a watershed moment for the aviation industry in dealing with the effects of volcanic ash, ICAO cautions that any operational, political or organizational modifications to its guidance material that arise from it most likely will not come quickly. “It’s hard to say at this point, but guidance material itself takes a relatively long time because it has to go through a tight and strict analytical process to make sure that it’s valid and gets input from states and the airlines and manufacturers,” Chagnon said. “The process is always long, but it certainly has proved its usefulness over the years.”

Meanwhile, geologists specializing in volcanoes have criticized the air transport industry for failing to confront the threat of volcanic ash and devise engineering and safety strategies for dealing with it. One leading volcanologist told the BBC that he had repeatedly tried to persuade leading airlines to work jointly on the issue, only to be told that the issue was not viewed as a priority. 

Engine Makers Respond Cautiously but Checks Could Cause Delays

Engine manufacturers remained extremely cautious in their public pronouncements on the impact of volcanic ash on their products, but behind the scenes the industry has been busily liaising with aviation authorities to come to grips with a challenge that threatens the viability of many air carriers.

Pratt & Whitney Canada posted the following advice on its Web site regarding volcanic ash encounters:

“P&WC does not recommend operation in conditions where volcanic ash is present. Volcanic ash may clog air filters of turbine engines, block cooling air passages, erode the gas path components and erode the protective paint on casings. Volcanic ash entering the engine can also melt in the combustor and then re-solidify on the static turbine vanes, potentially choking the turbine airflow and leading to surging and an in-flight shutdown.

It is also noted that there is a high level of acidity associated with volcanic ash, and this may also lead to deterioration of engine components. Should you experience an encounter with volcanic ash, P&WC advises you follow the recommendations contained within the engine maintenance manual.”

Rolls-Royce declined to publish any specific guidance, stating simply: “Rolls-Royce is working closely with a multinational, cross-industry group to ensure that the level of the impact of volcanic ash on our engines is properly understood. As always, safety is the first priority. We are working hard to get a full understanding of the environmental issues to help achieve a timely resolution.”