Icelandic volcano disrupts flights again

Irish airline operators had a bad case of déjà-vu this morning when a cloud of ash from the Icelandic volcano Eyjafjallajökull swept over the Emerald Isle and grounded all flights. The Outer Hebrides islands of Scotland were also affected. Flights in the rest of the UK operated normally.

The Irish Aviation Authority canceled all flights in Northern Ireland and the Republic of Ireland starting at 7am local time and allowed them to resume at 1pm local time. The few small airports affected in the Hebrides also plan to reopen sometime in the afternoon.

The ash cloud only reached about 20,000 feet so flights crossing Irish airspace at cruising altitude were not affected. The cloud was thin and sparse compared with the massive one that grounded flights for six days last month. It thinned out to safe levels by the afternoon, prompting aviation officials to reopen service.

Amazing video shows European aviation “rebooted” after Volcanic disruption

Airspace Rebooted from ItoWorld on Vimeo.

Yesterday, we showed you the effects of the Icelandic volcano in a stunning infographic – and today you can see the effects the disruption had on the European airspace.

This is one mesmerizing video – it shows the “reboot” of air traffic, essentially going from a zero-flights state, to what can be considered a “normal” day.

The effect is amazing – you can clearly see the entire United Kingdom and Western Europe shut down (give or take one or two flights), then slowly growing. Be sure to check the date slider on the bottom left to get an idea of the duration of the disruption., via Gizmodo

Was there a silver lining to that volcanic ash cloud?

Well, no. Millions of people– and not just air travelers– were affected by that giant cloud of volcanic ash that cancelled flights into and out of Europe last week, including flower salesmen in Kenya, potential organ transplant recipients in Germany, and injured U.S. troops in Iraq and Afghanistan.

But some are now declaring that there’s a silver lining to the Great Smoke Monster Uprising of 2010. Keith Sawyer, a psychology professor at Washington University in St. Louis, says that gridlock at the airport might actually be good for travelers because it will help them rediscover their inherent “creativity.” From the article:

Like it or not, stranded travelers around the globe are suddenly finding themselves with a lot of unscheduled time on their hands, and idle time is a key ingredient to becoming more creative in your personal and professional lives, says Sawyer.

As Russ Roberts points out, the only explanation for Sawyer’s odd hypothesis is that the man has never had his flight canceled or delayed.

Sawyer is not alone in trying to decipher a minuscule, probably illusory bright spot in a sea of horribleness. The Pittsburgh Post-Gazette thinks it will be a boon for the upcoming Pittsburgh Marathon. (Woo-hoo!) Elsewhere, investment bankers may stand to profit. (Double woo-hoo!) And FedEx also sees a possible silver lining in the mess.

While I admire the optimism, can’t we all just agree that the interruption of air travel into and out of Europe for almost a week was a completely awful thing? No silver lining. No “but on the other hand…” Thousands of people lost loads of money, many others were inconvenienced beyond belief, still others didn’t receive the medicines (or organs!) they needed. It is a little like pointing out that 9/11 was terrible but at least it “brought the country together.” No, it was terrible, period. So was last week.

For a more thoughtful consideration of the implications of the recent air travel disruption, check out Eric Weiner’s piece over at World Hum “Seven Lessons from the Great Volcano Shutdown of 2010.”

Why can’t planes fly near volcanic ash? A (very) brief look at engine failure

Nearly a week into the volcanic ash crisis plaguing swaths of Europe, passengers and airlines alike are starting to tire of the restricted airspace. The haunting cloud drifting thousands of feet above Earth’s surface is often invisible to the naked eye both at ground level and high into the reaches of the troposphere, causing many to wonder how this material could impact a flight. Could all of these microscopic particles of ash really be that big of problem?

Yes, and in many ways.

Large volumes of volcanic ash have an obvious effect on flight performance. Any particulate getting into cooling holes will cause the engine pressure and temperature to increase, dropping efficiency and potentially causing serious issues inside of the engine. This failure mechanisms poses an immediate and large threat to aircraft safety and is the primary situation that airlines are trying to avoid.

But even small volumes — parts per million of the material — can have a long-term detrimental effect on engine performance.

Typical engine combustors operate at extremely high temperatures — hot enough to melt most metals — and the materials used in each component are specially designed to withstand this heat. The single-crystal turbine blades used in the fabrication of commercial engines often are exposed to temperatures well over 2500°F, and because of this are coated with a special Thermal Barrier Coating (TBC) to prevent overheating. In short, the TBCs prevent the turbine blades from melting.Part of what helps the TBCs do their job is their microstructure. Instead of being fully crystalline, solid materials like the compressor blades, most coatings are porous and less dense, preventing them from transferring too much heat. But this also subjects them to infiltration by foreign particles like calcium magnesium alumino silicate (aka CMAS, formed in and near sand particles) or volcanic ash.

Over time, these embedded particles fill in the pores of the TBC, and they remain in the microstructure as the engine gets hot and cold over and over again. Each time the engine heats and cools, this thermal cycling creates strain between the two materials, and like a sealed bottle of water in the freezer, the container eventually will burst. And once the TBC breaks down, heat can flow freely to the compressor blades, potentially melting a section and causing a catastrophic failure.

Depending on the volume of ash or particle ingested, this can happen quickly over several engine cycles or over a long term of repeated use. But the result is the same: failure during operation.

TBC degradation is only one mechanism for long term failure. Engineers also need to consider abrasion, creep and a host of other materials problems that can result from interaction between volcanic ash and highly specialized engine components.

As you can probably guess, this is partially why the European Aviation Safety Agency is being so cautious with easing restrictions on airspace — many of the long term effects of volcanic ash (which varies in composition by geographic location) on engine components are unknown. Only with time, testing and weeks of analysis will the full impact of these materials be know. Until then, we’re going to have to wait for the skies to clear.

Read more about the short term effects of volcanic ash at popsci.

Check out Alaska Airlines’ operating procedure near ash here.

Boeing’s comprehensive study on engine performance in ash clouds can be found here.

Walt Disney World offers free tickets for stranded European travelers

Walt Disney World is offering free one-day park hopper tickets to travelers stuck in the Orlando area because of the air travel disruption in Europe.

The tickets will be available today and Wednesday and are good for admission to the Magic Kingdom, EPCOT (to see the spring Flower and Garden Festival, perhaps), Disney’s Hollywood Studios and Animal Kingdom. These passes also include admission to Disney World’s two water parks, Blizzard Beach and Typhoon Lagoon.

To get a free Disney World ticket, you must show a canceled airline ticket or expired boarding pass for a European flight, as well as a passport or other photo ID. You can also get reimbursed for Disney’s $14-per-day parking fees if you have to pay them to get to the parks.

SeaWorld Orlando, Busch Gardens Tampa Bay and Aquatica started offering a similar deal over the weekend.

The Orlando Convention and Visitors Bureau is maintaining an online list of of hotel and attraction discounts available to those stranded by the volcanic ash cloud.