Airline Hopes To Avoid Volcanic Ash Clouds With New Technology

Volcanic ash is something commercial airliners want nothing to do with. When Alaska’s Cleveland volcano erupted not long ago, shooting low levels of ash into the atmosphere, many airlines were concerned. Another blast could send ash higher, directly into their flight path between Asia and North America, causing major flight schedule disruptions. But while most airlines watch and wait, one is taking some proactive steps to deal with volcanic activity.

Ash clouds are a major problem for commercial airliners, which can literally fall out of the sky if they attempt to fly through one. The problem is the tiny volcanic ash particles. If they get into a jet engine, ash particles can block the ventilation holes that let in air to cool the engine. Accumulate enough of them and engine heat can transform the particles back into molten lava, something you don’t want in your jet engine. In 2010, Iceland’s Eyjafjallajökull volcano ejected an ash plume 30,000 feet into the sky, crippling airlines in northwest Europe for days as nearly 20 airports closed their airspace.Looking for ways to minimize the effect of volcanic eruptions, EasyJet has partnered with aircraft manufacturer Airbus and Nicarnica Aviation, a company that specializes in remote sensing technology to detect ash at the speed and altitude of commercial aircraft. To do that, EasyJet will fly a ton of volcanic ash from Iceland to an Airbus base in France where it will test the new uses for infrared technology-based Airborne Volcanic Object Imaging Detector (AVOID) equipment in August.

During the test, an Airbus plane will disperse the ash into the atmosphere and create an artificial ash cloud. A second Airbus test aircraft equipped with AVOID technology will (hopefully) detect and avoid the artificial ash cloud at over 30,000 feet.

Want to see an ash cloud up close, as it is being created? Check out this video:

[Image credit – Flickr user coolinsights]

Some German airports shut because of Iceland volcano

Ash from the Icelandic volcano Grimsvötn that caused hundreds of flight cancellations in the UK, Denmark, and Norway yesterday has now moved over Germany, shutting down airports in the north of the country.

Hamburg and Bremen airports are closed. Berlin airport will probably close this morning as well. At least 600 flights are expected to be affected.

Poland may also be affected today but otherwise flights in, out, and around Europe should be operating. There may be knock-on delays because of the disruption in Germany so check ahead before going to the airport.

In better news, Grimsvötn has stopped erupting. Let’s hope it keeps behaving.

Have you been affected by the volcanic ash? Feel free to vent in the comments section!

[Micrograph of volcanic ash courtesy US Geological Survey]

UPDATE: (9:23 EDT) The BBC is reporting that Hamburg, Bremen, and Berlin airports have reopened. About 700 flights were cancelled.

Iceland volcano cancels flights

Here we go again.

After last year’s misery from the Eyjafjallajökull eruption, now another Icelandic volcano, Grimsvötn, is causing a new round of worries.

More than 250 flights have already been canceled as a cloud of volcanic ash blows over Scotland. Most of Ireland, northern Wales, and northern England will see the ash later today.

Several Scottish airports have been affected, including major ones such as Edinburgh and Glasgow. Other airports that will likely have problems today include Londonderry, Prestwick, Durham Tees Valley, Newcastle, and Carlisle. Officials say the cloud should move on and flights from Edinburgh and Glasgow will resume this afternoon. Airports in the far north of Scotland should get the all-clear tomorrow. Of course, that’s assuming there are no more eruptions or changes in the wind.

Luckily the wind has taken much of the ash away from populated areas, over the far north Atlantic, eastern Greenland, and north of Scandinavia.

Several airlines are not flying through Scottish airspace. You can see a full list here. Since the northerly route between Europe and North America passes through the ash cloud, transatlantic flights may have to be diverted, causing delays. Check ahead before going to the airport.

So far this doesn’t look like another Eyjafjallajökull. The Grimsvötn eruption is smaller and the ash particles are bigger, meaning they fall to earth more quickly instead of hanging in the atmosphere for days.

Have your travel plans been affected by the Grimsvötn eruption? Tell us about it in the comments section!

[Photo courtesy Roger McLassus]

UK eases airline ash restrictions

The United Kingdom’s Civil Aviation Authority (CAA) has announced it will double the amount of ash deemed safe for flying in order to ease further disruptions to service from Eyjafjallajökull’s continuing eruptions.

The move comes after massive pressure from the airlines both during and after last month’s airport shutdown.

A CAA press release states, “A new area of operations can now be introduced that creates a ‘Time Limited Zone (TLZ)’ between the black ‘No Fly Zone (NFZ)’ and the red ‘Enhanced Procedures Zone (EPZ)’. Aircraft and engine manufacturers, based on new research and analysis, have agreed that it is safe to allow operations in the new zone for a limited time at higher ash densities than is currently permitted.”

Ash in this new zone can be 0.004 grams per cubic meter of air, twice the prior limit. The new regulations come into effect at noon today.

Airlines are, of course, happy. Jim French, chief executive at Flybe, said that if he new rules had been in place during the latest disruption of the past 48 hours, he would have only had to cancel 21 flights instead of 381.

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.