Airline Hopes To Avoid Volcanic Ash Clouds With New Technology

volcanic ashVolcanic 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]

Plane Answers: How close are airliners allowed to fly?

Welcome to Plane Answers, where our resident airline pilot, Kent Wien, answers your questions about everything from takeoff to touchdown and beyond. Have a question of your own? Ask away!

This question was submitted by Jim,

Hi Kent,

My question concerns how much advance notice pilots get when there are other planes in their immediate air space. In some of my travels, while at cruising altitude, I’ve seen other planes cross paths just below us. Knowing how many planes fill the sky each day and knowing that your reaction time is minimal, I wonder how pilots and controllers work together to keep all those planes apart. Also, what’s the rule on how much distance must there be between planes when on the same route and at intersection points?Thanks Jim,

I know it can be a little disconcerting to see another airplane cross under or zip by overhead just as you look out the window of an airliner.

Air traffic controllers have rules on how far laterally they must keep airplanes apart as well as how much vertical space needs to be kept between them.

For lateral separation, airplanes that are en route–flying faster and further away from the ATC facility–must have at least 5 nautical miles between them. When the airplanes enter the approach controller’s airspace, that requirement goes down to 3 nautical miles. Finally, when the airplane is in the control of an airport’s tower controller, aircraft can be spaced much closer if that controller has visual contact with the airplanes or if at least one pilot reports they have the other aircraft in sight. A good example of this is the visual approaches to San Francisco where airplanes are lined up on final approach for the parallel runways. You would think the airplanes are flying in formation at times.

This visual separation doesn’t apply when airplanes are in the clouds, in which case the controllers keep airplanes spaced about 2 1/2 NM apart, more if the preceding aircraft is a heavy (over 250,000 pounds–757 or larger) and the following aircraft is not. This limitation is a function of the wake turbulence generated by larger airplanes.

But I suspect the airplanes that you’ve been seeing lately have been even closer laterally than that. Because of some technology improvements to corporate jets and airliners, most of the world has adopted the Reduced Vertical Separation Minima (RVSM) standards. This allows aircraft flying above 29,000 feet to be spaced at 1,000 foot intervals. In the past, that number was 2,000 feet apart.

This has actually had the effect of doubling our airspace above 29,000 feet, which allows for more direct routing and the ability for us to get out of annoying areas of turbulence.

Westbound aircraft are normally put at the even flight levels (altitudes) and eastbound aircraft fly at the odd levels. That doesn’t apply to the North Atlantic, where most of the traffic flies westbound in the morning and eastbound in the afternoon. In that case, airplanes are spaced 1000 feet apart which makes for some great views from our seat as you can see from the following video clip:

Have a question for Kent? Ask away and he’ll pick one to answer here on Friday.