Narrative:

The runways at pcm are runway 28/10. A C172 was making a VOR approach to runway 28. ATC advised the C172 to 'cancel as soon as possible' because my aircraft (182RG) and a piper seneca were inbound on a runway 10 GPS approach. The C172 pilot had a thick foreign accent and was difficult to understand. I monitored the unicom frequency and tpa approach. The C172 pilot canceled his IFR. As I passed the OM I was cleared for the approach and went to unicom and asked the C172 his location. He replied he was downwind for runway 28. I then received a tis traffic conflict on my mfd. Next; the C172 pilot said he was 'crossing over' to go downwind for runway 10. I was now descending through 800 ft AGL in rain and clouds. I had no visibility down or forward. When I came out of the clouds I instructed the C172 to remain downwind until I was able to locate him visually. I was extremely distraction while avoiding a collision and failed to cancel my IFR flight plan until approximately 45 mins later. I then called flight service and they verified my cancellation with tpa approach. The C172 pilot created a hazard by not landing on runway 28 as expected. He was below 500 ft when I finally saw him pass my left wing. He was definitely trying to go VFR under solid IFR conditions.

Related reports:

Google
 

Original NASA ASRS Text

Title: AN IMC IFR C182 PLT ON A PCM RWY 10 GPS ENCOUNTERED A C172 AFTER A VOR 28 APCH IN WHICH HE TURNED A RWY 10 DOWNWIND. THE RPTR FAILED TO CNX IFR.

Narrative: THE RWYS AT PCM ARE RWY 28/10. A C172 WAS MAKING A VOR APCH TO RWY 28. ATC ADVISED THE C172 TO 'CANCEL ASAP' BECAUSE MY ACFT (182RG) AND A PIPER SENECA WERE INBOUND ON A RWY 10 GPS APCH. THE C172 PLT HAD A THICK FOREIGN ACCENT AND WAS DIFFICULT TO UNDERSTAND. I MONITORED THE UNICOM FREQ AND TPA APCH. THE C172 PLT CANCELED HIS IFR. AS I PASSED THE OM I WAS CLRED FOR THE APCH AND WENT TO UNICOM AND ASKED THE C172 HIS LOCATION. HE REPLIED HE WAS DOWNWIND FOR RWY 28. I THEN RECEIVED A TIS TFC CONFLICT ON MY MFD. NEXT; THE C172 PLT SAID HE WAS 'XING OVER' TO GO DOWNWIND FOR RWY 10. I WAS NOW DSNDING THROUGH 800 FT AGL IN RAIN AND CLOUDS. I HAD NO VISIBILITY DOWN OR FORWARD. WHEN I CAME OUT OF THE CLOUDS I INSTRUCTED THE C172 TO REMAIN DOWNWIND UNTIL I WAS ABLE TO LOCATE HIM VISUALLY. I WAS EXTREMELY DISTR WHILE AVOIDING A COLLISION AND FAILED TO CANCEL MY IFR FLT PLAN UNTIL APPROX 45 MINS LATER. I THEN CALLED FLT SVC AND THEY VERIFIED MY CANCELLATION WITH TPA APCH. THE C172 PLT CREATED A HAZARD BY NOT LNDG ON RWY 28 AS EXPECTED. HE WAS BELOW 500 FT WHEN I FINALLY SAW HIM PASS MY L WING. HE WAS DEFINITELY TRYING TO GO VFR UNDER SOLID IFR CONDITIONS.

Data retrieved from NASA's ASRS site as of January 2009 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.