Narrative:

I flew flight from stockholm to chicago. On approach at ord it seemed to be very hazy although the visibility was 8 mi. After landing I confirmed what I had suspected. All the cockpit windows were coated with a thin powdery film. I had noticed this occurring on other flts both after arrival and on aircraft that had just returned from europe, and I was leaving on before the windows were washed. After we arrived at the gate, I opened my side window, wet my fingers and wiped a hole in the film. I would estimate it reduced visibility by at least 10%. A sample of the residue could be collected very easily for analysis. I am certain that it is volcanic ash from mt pinatubo (see enclosed USA today article). I am not only concerned about the long-term effects this ash will have on aircraft components i.e., engines, air cycle machines, etc., but also on my and my fellow crew members health. Our route of flight took us from stockholm to trondheim, norway to just north of iceland across southern greenland to jelco intersection, then on a direct line to sault sainte marie then to ord. Flight duration was approximately 8 hours 45 mins. We were at FL350 to trm, 370 to jelco, then 390 to ord.

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Original NASA ASRS Text

Title: ACFT FLYING FROM SWEDEN TO ORD COLLECTS A FILM OF VOLCANIC ASH WHICH REDUCES VISIBILITY THROUGH THE WINDSHIELD APPROX 10 PERCENT

Narrative: I FLEW FLT FROM STOCKHOLM TO CHICAGO. ON APCH AT ORD IT SEEMED TO BE VERY HAZY ALTHOUGH THE VISIBILITY WAS 8 MI. AFTER LNDG I CONFIRMED WHAT I HAD SUSPECTED. ALL THE COCKPIT WINDOWS WERE COATED WITH A THIN POWDERY FILM. I HAD NOTICED THIS OCCURRING ON OTHER FLTS BOTH AFTER ARR AND ON ACFT THAT HAD JUST RETURNED FROM EUROPE, AND I WAS LEAVING ON BEFORE THE WINDOWS WERE WASHED. AFTER WE ARRIVED AT THE GATE, I OPENED MY SIDE WINDOW, WET MY FINGERS AND WIPED A HOLE IN THE FILM. I WOULD ESTIMATE IT REDUCED VISIBILITY BY AT LEAST 10%. A SAMPLE OF THE RESIDUE COULD BE COLLECTED VERY EASILY FOR ANALYSIS. I AM CERTAIN THAT IT IS VOLCANIC ASH FROM MT PINATUBO (SEE ENCLOSED USA TODAY ARTICLE). I AM NOT ONLY CONCERNED ABOUT THE LONG-TERM EFFECTS THIS ASH WILL HAVE ON ACFT COMPONENTS I.E., ENGS, AIR CYCLE MACHINES, ETC., BUT ALSO ON MY AND MY FELLOW CREW MEMBERS HEALTH. OUR RTE OF FLT TOOK US FROM STOCKHOLM TO TRONDHEIM, NORWAY TO JUST N OF ICELAND ACROSS SOUTHERN GREENLAND TO JELCO INTXN, THEN ON A DIRECT LINE TO SAULT SAINTE MARIE THEN TO ORD. FLT DURATION WAS APPROX 8 HRS 45 MINS. WE WERE AT FL350 TO TRM, 370 TO JELCO, THEN 390 TO ORD.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.