Thursday, April 22, 2010

"Airspace Closure Was Exacerbated by Too Much Modeling, Too Little Research"

We have a deep and abiding interest in models.*
From Bloomberg:
A shutdown of European airspace that cost carriers $1.7 billion following a volcanic eruption in Iceland was exacerbated by a lack of research into the effects of ash on jet engines and over-reliance on computer modeling.

While the blast was unusually disruptive because of a rare mix of ice and molten rock, together with a wind direction that blew dust to Europe, flight bans would have been shorter with a better understanding of engine tolerances and cloud density.

“This has highlighted a black hole in our understanding,” said David Macdonald, who manages the private-jet unit of London-charter company Air Partner Plc. “There needs to be some urgent research into what concentration of ash is permissible.”

More than 100,000 flights were canceled following the April 14 eruption amid concern that glass-like particles formed when lava was cooled by ice might melt in aircraft engines and clog turbines. European transport ministers took five days to agree that airports could open with the dust still in the air.

Carriers including London-based British Airways Plc said soon after the eruption of Iceland’s Eyjafjallajökull volcano that test flights had shown no damage to aircraft or engines.

Governments initially resisted the calls for services to resume, citing advice from the International Civil Aviation Organization to bar planes from flying through any level of volcanic debris. They later ruled that operations were safe except where dust levels were at least 10 times the norm, as assessed by the U.K. Met Office’s Volcanic Ash Advisory Centre.

Even then, the final decision was left to national air- traffic-control bodies, keeping airports including London Heathrow, Europe’s busiest, closed for an extra day.

‘Never an Issue’

“The rule saying you do not fly jets through volcanic ash was put in place years ago and had never really been an issue,” Jonathan Nicholson, a spokesman for Britain’s Civil Aviation Authority, said in a telephone interview. “ICAO had been looking at trying to implement a more realistic level for some years but there was no pressure to do so as they never had a volcanic ash incident over such a densely populated area.”

Compounding the problem was a lack of data on the effects of the type of glassy dust produced by the Icelandic eruption, in which a vent opened under a glacier, causing explosions that blew ash 7 kilometers (4.3 miles) high as fire met ice.

Lufthansa Probe

Test flights performed by British Airways, Air France-KLM Group and others focused on detecting any impact from the ash, rather than analyzing air content, and only after the reopening of airspace was a probe deployed to measure the concentration and distribution of the plume. Results from the 1.6-ton research container -- built by the Max Planck Institute and flown around Europe on a Deutsche Lufthansa AG Airbus SAS A340 jetliner -- may be revealed today, spokesman Peter Schneckenleitner said.

Neither were guidelines from engine manufacturers of immediate use, with analysis of the effects of ash not part of the process for winning safety approval for new powerplants.

“With no engine-certification testing required for volcanic ash, no limits currently exist,” said Deborah Case, a spokeswoman for the aviation unit of Fairfield, Connecticut- based General Electric Co., the biggest maker of jet engines.

While United Technologies Corp.’s Pratt & Whitney unit reissued guidelines to airlines following the eruption, the advice concerned steps to be taken on encountering ash rather than on the levels in which an aircraft might safely operate.

“With the amount of research into jet engines, you’d think somebody would have written a doctorate on the impact of ash,” Air Charter’s Macdonald said. “We need more research because at the moment it seems open to interpretation.”

Projected Airflows

Decisions on airspace closures were based largely on projected airflows from Met Office maps as interpreted by Brussels-based Eurocontrol, the body that coordinates flight paths across the region, rather than on actual readings.

“Regulators need to better understand and measure the particle densities at different altitudes,” Paul Hayes, director of safety at aviation consultant Ascend, said in an interview. “Just how dense is the ash and does it pose any real threat to the safety of aircraft?”

New rules for operations were eventually decided by national regulators in consultation with manufacturers. GE and other engine makers worked with the CAA to reach agreement on ash-tolerance levels after reviewing data from previous incidents and drawing on experience from areas prone to volcanic activity, such as Alaska, GE’s Case said in an interview.

Right Response

Governments acted “extremely correctly” given existing regulations, Helen Kearns, a spokeswoman for the European Commission, said today at a press briefing in Brussels.

“There was a model that was internationally recognized, with international guidelines for the European area,” Kearns said. “It was applied absolutely as it should have been by member states, who quite rightly put safety first.”>>>MORE

*The problem with models?:

"The map is not the territory"...

-Alfred Korzybski

Some of our prior posts on models:

The Financial Modelers' Manifesto

After the Crash: How Software Models Doomed the Markets

How Models Caused the Credit Crisis
Quants Lose that Old Black (Box) Magic
Finance: "Blame the models"
Climate Models Overheat Antarctica, New Study Finds
Climate modeling to require new breed of supercomputer
Computer Models: Climate scientists call for their own 'Manhattan Project'
Computer Models: " Misuse of Models" and "No model for policymaking"
Climate prediction: No model for success
Climate Models and Modeling
Based on Our Proprietary "What's on T.V." Timing Model...
How many Nobel Laureates Does it Take to Make Change...And: End of the Universe Puts
The New Math (Quant Funds)
Modeling*: The Map is Not the Territory
Inside Wall Street's Black Hole
Computer Models: Models’ Projections for Flu Miss Mark by Wide Margin
Obama: Swedish Model Would Be Impossible Here

The Swedish Model

As the [college] site that I lifted the picture from said:

(okay, sorry we know its tacky)

[hey, come on we're an all boy's team, what'd you expect!]