Narrative:

Flight departed north on the summa 5. At 8 DME, while in the turn to 070 degrees we were cleared to continue to heading 160 degrees to intercept the sea 143 degree outbound. On the 160 degree heading, 4.5 DME e-se of sea VOR at approximately 12000 ft and climbing at approximately 2000 FPM, a yellow traffic alert appeared on our TCASII. It showed +05 and within the inner circle of the 15 DME selection. My line of sight raised up to look out in that specific area and I saw this single engine aircraft at our 11:30 position and slightly higher. I simultaneously increased our rate of ascent and lowered the left wing instinctively to miss him. He dove to his right and passed within 100 ft of our left wing. With our rate of climb approximately 3000-3500 FPM the TCASII loudly proclaimed 'traffic, traffic.' the TCASII was a complete red arc with the exception of the 4000 FPM up and above portion. As he went by we could see that it was a red and white cessna 180. Without our alarm we 'probably' could have read his numbers. As passenger deplaned in rno, 2 alarmed people left their phone number as they had seen the cessna 180 pass by.

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Original NASA ASRS Text

Title: DURING VMC SUMMA DEP CLBING THROUGH 12000 FT RPTR EXPERIENCED TCASII AND NMAC WITH CESSNA 180.

Narrative: FLT DEPARTED N ON THE SUMMA 5. AT 8 DME, WHILE IN THE TURN TO 070 DEGS WE WERE CLRED TO CONTINUE TO HDG 160 DEGS TO INTERCEPT THE SEA 143 DEG OUTBOUND. ON THE 160 DEG HDG, 4.5 DME E-SE OF SEA VOR AT APPROX 12000 FT AND CLBING AT APPROX 2000 FPM, A YELLOW TFC ALERT APPEARED ON OUR TCASII. IT SHOWED +05 AND WITHIN THE INNER CIRCLE OF THE 15 DME SELECTION. MY LINE OF SIGHT RAISED UP TO LOOK OUT IN THAT SPECIFIC AREA AND I SAW THIS SINGLE ENG ACFT AT OUR 11:30 POS AND SLIGHTLY HIGHER. I SIMULTANEOUSLY INCREASED OUR RATE OF ASCENT AND LOWERED THE L WING INSTINCTIVELY TO MISS HIM. HE DOVE TO HIS R AND PASSED WITHIN 100 FT OF OUR L WING. WITH OUR RATE OF CLB APPROX 3000-3500 FPM THE TCASII LOUDLY PROCLAIMED 'TFC, TFC.' THE TCASII WAS A COMPLETE RED ARC WITH THE EXCEPTION OF THE 4000 FPM UP AND ABOVE PORTION. AS HE WENT BY WE COULD SEE THAT IT WAS A RED AND WHITE CESSNA 180. WITHOUT OUR ALARM WE 'PROBABLY' COULD HAVE READ HIS NUMBERS. AS PAX DEPLANED IN RNO, 2 ALARMED PEOPLE LEFT THEIR PHONE NUMBER AS THEY HAD SEEN THE CESSNA 180 PASS BY.

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.