Narrative:

Air carrier X on approach to mfr. Over the mountains. On vector to final. Supposedly #1 for the approach. Cleared and flying heading 090 degrees. Traffic advised to our left at 9500 ft. Same traffic on TCASII at 9900 ft. Air carrier Y, B737 also being controled and informed he was #2 for the approach. Puffy clouds all around. Bases of clouds approximately 9000-9500 ft. VFR traffic at 9500 ft to left not seen. Cleared to 9600 ft. At 10600 ft slowed from 250 KTS to 210 KTS, then started slow descent. (I saw the initial situation and slowed and delayed descent). At just under 10000 ft got RA 'climb, climb.' immediately climbed. Directed to climb 12 1/2 to 15 degrees. RA stopped at 11000 ft. Immediately got another RA 'climb, climb.' immediately climbed. Copilot then saw aircraft to right. Viscount crossed under -- directly under -- 400-800 ft below. (He was big!) controller then turned us to heading of 250 degrees. By now we were at 12000 ft. In turn to 250 degrees got another RA 'climb' off of viscount, who was now in front of us. Heading had not varied during procedures -- was 090 degrees until turned left to 250 degrees. After landing spoke with controller at eugene approach tower, medford sector. He pointed out he originally had traffic altitude separated -- at least he expressed dissatisfaction with TCASII. He said he would turn in TCASII report and NASA report. After landing, spoke with Y crew. They had RA on X, but X was in sight and I don't believe they followed RA. They then got RA off of the same VFR traffic. I don't know if they followed it or not. We followed correct procedures and it appears Y did too. It appears controller followed correct procedures, but I am having difficulty understanding how #1 and #2 aircraft in pattern were on an intercept course, despite fact they had altitude separation.

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Original NASA ASRS Text

Title: ACR X TCASII RA WITH VFR ACFT HAD LTSS FROM ACR Y. EVASIVE ACTION TAKEN.

Narrative: ACR X ON APCH TO MFR. OVER THE MOUNTAINS. ON VECTOR TO FINAL. SUPPOSEDLY #1 FOR THE APCH. CLRED AND FLYING HDG 090 DEGS. TFC ADVISED TO OUR L AT 9500 FT. SAME TFC ON TCASII AT 9900 FT. ACR Y, B737 ALSO BEING CTLED AND INFORMED HE WAS #2 FOR THE APCH. PUFFY CLOUDS ALL AROUND. BASES OF CLOUDS APPROX 9000-9500 FT. VFR TFC AT 9500 FT TO L NOT SEEN. CLRED TO 9600 FT. AT 10600 FT SLOWED FROM 250 KTS TO 210 KTS, THEN STARTED SLOW DSCNT. (I SAW THE INITIAL SIT AND SLOWED AND DELAYED DSCNT). AT JUST UNDER 10000 FT GOT RA 'CLB, CLB.' IMMEDIATELY CLBED. DIRECTED TO CLB 12 1/2 TO 15 DEGS. RA STOPPED AT 11000 FT. IMMEDIATELY GOT ANOTHER RA 'CLB, CLB.' IMMEDIATELY CLBED. COPLT THEN SAW ACFT TO R. VISCOUNT CROSSED UNDER -- DIRECTLY UNDER -- 400-800 FT BELOW. (HE WAS BIG!) CTLR THEN TURNED US TO HDG OF 250 DEGS. BY NOW WE WERE AT 12000 FT. IN TURN TO 250 DEGS GOT ANOTHER RA 'CLB' OFF OF VISCOUNT, WHO WAS NOW IN FRONT OF US. HDG HAD NOT VARIED DURING PROCS -- WAS 090 DEGS UNTIL TURNED L TO 250 DEGS. AFTER LNDG SPOKE WITH CTLR AT EUGENE APCH TWR, MEDFORD SECTOR. HE POINTED OUT HE ORIGINALLY HAD TFC ALT SEPARATED -- AT LEAST HE EXPRESSED DISSATISFACTION WITH TCASII. HE SAID HE WOULD TURN IN TCASII RPT AND NASA RPT. AFTER LNDG, SPOKE WITH Y CREW. THEY HAD RA ON X, BUT X WAS IN SIGHT AND I DON'T BELIEVE THEY FOLLOWED RA. THEY THEN GOT RA OFF OF THE SAME VFR TFC. I DON'T KNOW IF THEY FOLLOWED IT OR NOT. WE FOLLOWED CORRECT PROCS AND IT APPEARS Y DID TOO. IT APPEARS CTLR FOLLOWED CORRECT PROCS, BUT I AM HAVING DIFFICULTY UNDERSTANDING HOW #1 AND #2 ACFT IN PATTERN WERE ON AN INTERCEPT COURSE, DESPITE FACT THEY HAD ALT SEPARATION.

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.