Narrative:

I was descending from 9000' on an IFR eastbound. After V216 to janesville, was given a vector by mke approach for landing at racine and told to descend to 2600. I was advised of traffic at 2 O'clock which I could not find. I was then advised of traffic at 12 O'clock which I did see and told approach. While descending through 5000' I found an aircraft converging straight at me at 9:30 at the same altitude. I made a diving right turn while the other aircraft made a climbing right turn. It was a light twin southbound. I did not hear any radio xmissions from him so I don't know if he was IFR. I called mke approach and asked if they saw the traffic on radar. All he said was that I was advised of traffic. I was advised of previous traffic but not of any traffic from 9-10 O'clock position. Even if I had been advised, there should have been separation maintained by approach. The 2 targets must have merged on radar. Maybe they were busy that day. Had one of us not seen each other I don't know if evasive action by one aircraft would have been enough.

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Original NASA ASRS Text

Title: NMAC BETWEEN 2 SMA ACFT WHILE UNDER RADAR MONITORING. TWO ACFT USED EVASIVE ACTION TO AVOID EACH OTHER.

Narrative: I WAS DESCENDING FROM 9000' ON AN IFR EBND. AFTER V216 TO JANESVILLE, WAS GIVEN A VECTOR BY MKE APCH FOR LNDG AT RACINE AND TOLD TO DSND TO 2600. I WAS ADVISED OF TFC AT 2 O'CLOCK WHICH I COULD NOT FIND. I WAS THEN ADVISED OF TFC AT 12 O'CLOCK WHICH I DID SEE AND TOLD APCH. WHILE DESCENDING THROUGH 5000' I FOUND AN ACFT CONVERGING STRAIGHT AT ME AT 9:30 AT THE SAME ALT. I MADE A DIVING RIGHT TURN WHILE THE OTHER ACFT MADE A CLIMBING RIGHT TURN. IT WAS A LIGHT TWIN SBND. I DID NOT HEAR ANY RADIO XMISSIONS FROM HIM SO I DON'T KNOW IF HE WAS IFR. I CALLED MKE APCH AND ASKED IF THEY SAW THE TFC ON RADAR. ALL HE SAID WAS THAT I WAS ADVISED OF TFC. I WAS ADVISED OF PREVIOUS TFC BUT NOT OF ANY TFC FROM 9-10 O'CLOCK POSITION. EVEN IF I HAD BEEN ADVISED, THERE SHOULD HAVE BEEN SEPARATION MAINTAINED BY APCH. THE 2 TARGETS MUST HAVE MERGED ON RADAR. MAYBE THEY WERE BUSY THAT DAY. HAD ONE OF US NOT SEEN EACH OTHER I DON'T KNOW IF EVASIVE ACTION BY ONE ACFT WOULD HAVE BEEN ENOUGH.

Data retrieved from NASA's ASRS site as of August 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.