Narrative:

I was flying an IFR arrival with a cfii. I was the PF and I am a CFI. ATC instructed us to turn left to a heading and told us to descend and maintain a prescribed altitude. I began the turn and descent as instructed, descending around 500-800 FPM. During the descent, ATC advised us of a safety alert, told us to expedite our descent, and gave us the position of another aircraft. I looked in the direction of the reported traffic and saw a twin engine aircraft (a C421 or similar) about 500 ft or more above us and crossing from forward and right to behind and to our left. I reported the traffic in sight and that it was not a factor. There was not a collision hazard. The WX en route was IMC and we were in a clear area between areas of clouds.

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Original NASA ASRS Text

Title: WHILE CONDUCTING AN IFR APCH INTO SCK, A C182 PLT IS ISSUED A TFC ALERT BY THE APCH CTLR AND SPOTS A C421 PASS WITHIN 500 FT.

Narrative: I WAS FLYING AN IFR ARR WITH A CFII. I WAS THE PF AND I AM A CFI. ATC INSTRUCTED US TO TURN L TO A HDG AND TOLD US TO DSND AND MAINTAIN A PRESCRIBED ALT. I BEGAN THE TURN AND DSCNT AS INSTRUCTED, DSNDING AROUND 500-800 FPM. DURING THE DSCNT, ATC ADVISED US OF A SAFETY ALERT, TOLD US TO EXPEDITE OUR DSCNT, AND GAVE US THE POS OF ANOTHER ACFT. I LOOKED IN THE DIRECTION OF THE RPTED TFC AND SAW A TWIN ENG ACFT (A C421 OR SIMILAR) ABOUT 500 FT OR MORE ABOVE US AND XING FROM FORWARD AND R TO BEHIND AND TO OUR L. I RPTED THE TFC IN SIGHT AND THAT IT WAS NOT A FACTOR. THERE WAS NOT A COLLISION HAZARD. THE WX ENRTE WAS IMC AND WE WERE IN A CLR AREA BTWN AREAS OF CLOUDS.

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.