Narrative:

Flying south of the chicago airspace, along the southern shore of lake michigan, we were cruising VFR at 11500 ft, to stay above a buildup, layer of scattered clouds. While still receiving flight following, we were given TA's of several airlines inbound to chicago at just above our altitude. We progressed further east, and chicago approach was too busy to provide flight following. As we flew east, we noticed the lower clouds dissipating, so decided to descend to a lower altitude for better separation from traffic. While descending we passed below and behind a DC9/MD80 type. Although traffic wasn't dangerously close, wake turbulence, could have resulted. Lesson learned was to check STAR charts before transversing busy airspace to avoid undesirable altitude selection. Note crossing fixes and altitudes.

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Original NASA ASRS Text

Title: A C206 PLT WORRIED THAT HE MAY HAVE ALMOST ENCOUNTERED WAKE TURB FROM AN MD80 WHILE FLYING IN C90 AIRSPACE.

Narrative: FLYING S OF THE CHICAGO AIRSPACE, ALONG THE SOUTHERN SHORE OF LAKE MICHIGAN, WE WERE CRUISING VFR AT 11500 FT, TO STAY ABOVE A BUILDUP, LAYER OF SCATTERED CLOUDS. WHILE STILL RECEIVING FLT FOLLOWING, WE WERE GIVEN TA'S OF SEVERAL AIRLINES INBOUND TO CHICAGO AT JUST ABOVE OUR ALT. WE PROGRESSED FURTHER E, AND CHICAGO APCH WAS TOO BUSY TO PROVIDE FLT FOLLOWING. AS WE FLEW E, WE NOTICED THE LOWER CLOUDS DISSIPATING, SO DECIDED TO DSND TO A LOWER ALT FOR BETTER SEPARATION FROM TFC. WHILE DSNDING WE PASSED BELOW AND BEHIND A DC9/MD80 TYPE. ALTHOUGH TFC WASN'T DANGEROUSLY CLOSE, WAKE TURB, COULD HAVE RESULTED. LESSON LEARNED WAS TO CHK STAR CHARTS BEFORE TRANSVERSING BUSY AIRSPACE TO AVOID UNDESIRABLE ALT SELECTION. NOTE XING FIXES AND ALTS.

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.