Narrative:

Descending on vectors from 4000 ft to 2000 ft, we were pointed out as traffic to the VFR cessna. He called us in sight and said he would follow us. He didn't! We picked him up visually about the time we got a TA which quickly changed to an RA for a 2100 FPM climb. We followed RA, passed traffic, proceeded to normal landing. Approach was off the hook because the VFR traffic called us in sight. The only problem I had with it all was that approach offered us no information about where the traffic was in relation to us or seemed to have noticed how close we came. I know it was an honest mistake and the controller had no obligation to us once the cessna had us in sight, but a little more information to us may have helped us resolve the situation more quickly and less closely. Supplemental information from acn 426886: I was on approach control frequency requesting permission to be inbound for landing. I was under the impression that the heading I was given would put me behind the aircraft that I was to follow to the airport. I saw the aircraft ahead and to my right which appeared to be below my altitude and descending -- I maintained my altitude. My attention was diverted by a transmission from another radio requesting my assistance. I heard a transmission from the aircraft which I was to follow that he was initiating a climb. I saw the airplane climbing through my altitude and pass overhead before I was able to react. I shouldn't have assumed that the heading that I was given would keep me clear of traffic. I should have been more vigilant in avoiding the conflict and I shouldn't have been distraction by the transmission from the other radio. Furthermore, the other aircraft seemed farther away than what it actually was. Therefore, it was not perceived as a threat until it was too late for me to react.

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Original NASA ASRS Text

Title: AN INBOUND DSNDING B737-400 PULLS UP TO AVOID A C172 THAT WAS SUPPOSED TO MAINTAIN VISUAL SEPARATION FROM THE B737.

Narrative: DSNDING ON VECTORS FROM 4000 FT TO 2000 FT, WE WERE POINTED OUT AS TFC TO THE VFR CESSNA. HE CALLED US IN SIGHT AND SAID HE WOULD FOLLOW US. HE DIDN'T! WE PICKED HIM UP VISUALLY ABOUT THE TIME WE GOT A TA WHICH QUICKLY CHANGED TO AN RA FOR A 2100 FPM CLB. WE FOLLOWED RA, PASSED TFC, PROCEEDED TO NORMAL LNDG. APCH WAS OFF THE HOOK BECAUSE THE VFR TFC CALLED US IN SIGHT. THE ONLY PROB I HAD WITH IT ALL WAS THAT APCH OFFERED US NO INFO ABOUT WHERE THE TFC WAS IN RELATION TO US OR SEEMED TO HAVE NOTICED HOW CLOSE WE CAME. I KNOW IT WAS AN HONEST MISTAKE AND THE CTLR HAD NO OBLIGATION TO US ONCE THE CESSNA HAD US IN SIGHT, BUT A LITTLE MORE INFO TO US MAY HAVE HELPED US RESOLVE THE SIT MORE QUICKLY AND LESS CLOSELY. SUPPLEMENTAL INFO FROM ACN 426886: I WAS ON APCH CTL FREQ REQUESTING PERMISSION TO BE INBOUND FOR LNDG. I WAS UNDER THE IMPRESSION THAT THE HDG I WAS GIVEN WOULD PUT ME BEHIND THE ACFT THAT I WAS TO FOLLOW TO THE ARPT. I SAW THE ACFT AHEAD AND TO MY R WHICH APPEARED TO BE BELOW MY ALT AND DSNDING -- I MAINTAINED MY ALT. MY ATTN WAS DIVERTED BY A XMISSION FROM ANOTHER RADIO REQUESTING MY ASSISTANCE. I HEARD A XMISSION FROM THE ACFT WHICH I WAS TO FOLLOW THAT HE WAS INITIATING A CLB. I SAW THE AIRPLANE CLBING THROUGH MY ALT AND PASS OVERHEAD BEFORE I WAS ABLE TO REACT. I SHOULDN'T HAVE ASSUMED THAT THE HDG THAT I WAS GIVEN WOULD KEEP ME CLR OF TFC. I SHOULD HAVE BEEN MORE VIGILANT IN AVOIDING THE CONFLICT AND I SHOULDN'T HAVE BEEN DISTR BY THE XMISSION FROM THE OTHER RADIO. FURTHERMORE, THE OTHER ACFT SEEMED FARTHER AWAY THAN WHAT IT ACTUALLY WAS. THEREFORE, IT WAS NOT PERCEIVED AS A THREAT UNTIL IT WAS TOO LATE FOR ME TO REACT.

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.