UM-Rolla Researchers To Study Aircraft Exhaust Over Ireland

Drs. Donald Hagen and Philip Whitefield -- researchers from UMR's Cloud andAerosol Sciences Laboratory -- are conducting the tests from Shannon,Ireland, starting next week and continuing through Oct. 15.

"There is no real problem that has been identified," Hagen says. "Thistesting is like going to the doctor to have a physical. You don't even havea pain in your side. But if we're going to see an effect, this is wherewe're going to see it."

Because of the number of flights from North America to Europe, the NorthAtlantic Flight Corridor is the most heavily traveled flight corridor inthe world. In addition to the volume, the aircraft follow narrow,well-defined flight paths.

"These paths -- called the Organized Flight Track -- make it particularlyinteresting to study," Hagen says.

It's so interesting that American and European scientists are teaming upthrough two programs -- NASA's SONEX project and the European EconomicCommunity's POLINAT 2 program -- to conduct the tests. SONEX stands forSass Ozone and Nitrogen Experiment. POLINAT is the European EconomicCommunity's study, called Pollution From Aircraft Emissions in the NorthAtlantic Flight Corridor.

"They decided to combine these operations because the value added would betremendous," Whitefield says. "Bringing the NASA DC-8 with all of its instrumentation on board and the Falcon (a German research plane) with allof its instrumentation on board, plus all the modeling by these scientists,will give us enormous data that will help us understand how aircraftemissions are affecting the atmosphere."

The results of this study may one day "provide the evidence upon which thedecision whether or not aircraft engines need to be modified will be made,"Hagen says.  

This international coordination involves everyone from weather forecastersto air traffic controllers to scientists studying specific data.

"We have to know the type of every single aircraft and its engine thatpasses through the flight corridor," Whitefield says.

The study begins with the DC-8 operating from Bangor, Maine, gathering testdata from an air mass anticipated to traverse the Atlantic through theOrganized Flight Track. The German research aircraft (the Falcon) will flythrough that same air mass as it passes through the eastern end of theNorth Atlantic Flight Corridor.

Tracking the air sample from start to finish is unique to this jointcampaign and will provide the basis for comparison that the scientistsneed, Hagen says.

"This is something you couldn't do if you measured the air mass only on oneside of the ocean," Hagen says. "You'd always be trying to guess what theoriginal state of the clean air parcel was."

After its initial stint in Maine, NASA's DC-8 will join the German Falconin Ireland.

Shannon, Ireland, provides an ideal base of operations. It's not only nearthe flight track, but "we also have exceptional cooperation from the flightcontrollers,"  Whitefield says.

Until five years ago, no one knew if it would be possible to measure theeffects of aircraft exhaust on the atmosphere. The first POLINAT, incombination with Germany's DLR program, Deutsche Forschungsanstalt furLuftund Raumfahrt, proved that it was possible. Hagen and Whitefield alsoparticipated in those studies -- in the winter of 1994 and the summer of1995 -- through NASA-funded research.

The report on data from the first POLINAT was published in September 1996.

"There was no one gusty, one-liner type conclusion," Hagen says. "What thereport did say was that it would be possible to define the effects ofaircraft on an air corridor."

According to the report, the combined data shows that aircraft areresponsible for a significant increase in the number of particles oraerosols in the immediate atmosphere in the North Atlantic Flight Corridor.

Beyond further testing, this joint campaign will overcome some of thechallenges the scientists have identified to date. During early testcampaigns, they discovered that the pollution from the aircraft exhaustspreads further than they had anticipated, "so we could never get out intoclean air in the studies that we were doing with the range of the aircraftthat we had," Hagen says. "This time the research aircraft will fly throughthe entire air mass between Iceland and the Azores, islands off the coastof Morocco. The plane will have to land and refuel before heading back."

Scientists from Germany, Norway, England, France, Switzerland, theNetherlands and the United States are participating in this joint 30-daycampaign.

"This is the cream of the cream of the European people in this field puttogether," Whitefield says. "It's a real honor and accolade for us to beinvited to participate."