Narrative:

I was advised of VFR traffic (small aircraft Y) northeast bound 5500' at 2 mi. I was eastbound IMC and advised controller of same. I returned to VMC and saw small aircraft Y descending and converging. I climbed to clear him and requested a 180 degree heading for avoidance while turning to avoid small aircraft Y. I was advised by controller that my mode C indicated 5300'. The climb was needed to avoid midair. Small aircraft Y was not under the control of the controller. I had just advised him 'no contact, I am IMC.' small aircraft Y was trying to avoid clouds but was not in layer VFR conditions. The controller should not assume that a 500' sep will be adequate or that the VFR aircraft will hold its altitude. He should have vectored me for avoidance early.

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Original NASA ASRS Text

Title: REPORTER HAS LESS SEVERE AIRBORNE CONFLICT WITH AN SMA THAT IS DODGING CLOUD ALONG AN AIRWAY.

Narrative: I WAS ADVISED OF VFR TFC (SMA Y) NE BOUND 5500' AT 2 MI. I WAS EBND IMC AND ADVISED CTLR OF SAME. I RETURNED TO VMC AND SAW SMA Y DSNDING AND CONVERGING. I CLBED TO CLR HIM AND REQUESTED A 180 DEG HDG FOR AVOIDANCE WHILE TURNING TO AVOID SMA Y. I WAS ADVISED BY CTLR THAT MY MODE C INDICATED 5300'. THE CLB WAS NEEDED TO AVOID MIDAIR. SMA Y WAS NOT UNDER THE CTL OF THE CTLR. I HAD JUST ADVISED HIM 'NO CONTACT, I AM IMC.' SMA Y WAS TRYING TO AVOID CLOUDS BUT WAS NOT IN LAYER VFR CONDITIONS. THE CTLR SHOULD NOT ASSUME THAT A 500' SEP WILL BE ADEQUATE OR THAT THE VFR ACFT WILL HOLD ITS ALT. HE SHOULD HAVE VECTORED ME FOR AVOIDANCE EARLY.

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.