Narrative:

Flight ay pij direct cak. We flew en route to cak at 8000 ft MSL. Cak approach kept us at 6000 ft MSL due to crossing traffic. Finally, about 5-6 mi south of cak we were cleared to descend for a visual straight-in approach and to contact tower. Just after contacting tower and while in a high-rate descent, we were advised of a non mode-C VFR aircraft converging on our approach path (from west to east). We were passing through approximately 3000 ft MSL and saw the light blue high wing single engine as it was in an evasive turn (right). We could not alter our descent and it seemed the most expeditious action to clear his flight path by descending rapidly. He appeared to be in the control zone and was not talking to cak approach or tower. We had a follow-up conversation with cak tower and they said they were going to track the unknown aircraft and determine if it had properly flown in the cak airspace.

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Original NASA ASRS Text

Title: NMAC

Narrative: FLT AY PIJ DIRECT CAK. WE FLEW ENRTE TO CAK AT 8000 FT MSL. CAK APCH KEPT US AT 6000 FT MSL DUE TO XING TFC. FINALLY, ABOUT 5-6 MI S OF CAK WE WERE CLRED TO DSND FOR A VISUAL STRAIGHT-IN APCH AND TO CONTACT TWR. JUST AFTER CONTACTING TWR AND WHILE IN A HIGH-RATE DSCNT, WE WERE ADVISED OF A NON MODE-C VFR ACFT CONVERGING ON OUR APCH PATH (FROM W TO E). WE WERE PASSING THROUGH APPROX 3000 FT MSL AND SAW THE LIGHT BLUE HIGH WING SINGLE ENG AS IT WAS IN AN EVASIVE TURN (R). WE COULD NOT ALTER OUR DSCNT AND IT SEEMED THE MOST EXPEDITIOUS ACTION TO CLR HIS FLT PATH BY DSNDING RAPIDLY. HE APPEARED TO BE IN THE CTL ZONE AND WAS NOT TALKING TO CAK APCH OR TWR. WE HAD A FOLLOW-UP CONVERSATION WITH CAK TWR AND THEY SAID THEY WERE GOING TO TRACK THE UNKNOWN ACFT AND DETERMINE IF IT HAD PROPERLY FLOWN IN THE CAK AIRSPACE.

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.