Narrative:

Air carrier flight X heavy was inbound from cedes intersection on a heading to intercept the sfo VOR 095 degree radial for the quiet bridge visual to runway 28R. Traffic was reported as an air carrier flight Y heavy at 12 O'clock. The crew reported the traffic in sight. Approach then gave a heading of 230 degrees for separation. On this heading, flight X crossed the centerline of both runway 28R and runway 28L. Traffic was observed at 12 O'clock, and a TCASII 'TA' was received. The traffic flashed his landing lights as flight X was cleared for the quiet bridge visual to runway 28R. The other aircraft, air carrier flight Z (B-737) asked about the traffic, and were told to 'report the 757 in sight.' the 737 did so, and was cleared for the tip toe to runway 28L. The 737 was given a speed of 180 KTS and the 757 was told to slow to 150 KTS to allow the 737 to 'catch up.' when the 737 was 1 mi in trail and at the same altitude, I looked aback and visually acquired him. The controller asked air carrier X if he had the 737 in sight, and he replied that he did. At the time, I was wondering why the 737 would remain in this hazardous position because of wake vortices (wind was 300 degrees at 20 KTS) at that time, ATC told air carrier X to maintain visual separation from the 737, as the 737 passed us with a 20-30 KT speed advantage. I contacted the 737 crew and they told me that they understood the 'catch-up' to mean 'pass.' they were going to pass, regardless, to avoid the 757 wake. While the onus was on them to maintain visual and wake separation, it appears that this responsibility was transferred to the 757, when the overtake was obvious. Who's got the lead? Who gets violated for losing sight/passing? Visuals at sfo are an airshow.

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Original NASA ASRS Text

Title: RPTR UNCOMFORTABLE WITH VISUAL RESPONSIBILITY CHANGES BTWN 3 ACFT ON PARALLEL APCH TO RWY 28L AND RWY 28R AT SFO. RPTR X ACFT WAS TOLD TO SLOW TO 150 KTS AS HE WAS FOLLOWING Y ACFT AND TO ALLOW Z ACFT TO 'CATCH UP' ALONGSIDE, HOWEVER Z ACFT PASSED X WHICH Z WAS NOT SUPPOSED TO DO.

Narrative: ACR FLT X HVY WAS INBOUND FROM CEDES INTXN ON A HDG TO INTERCEPT THE SFO VOR 095 DEG RADIAL FOR THE QUIET BRIDGE VISUAL TO RWY 28R. TFC WAS RPTED AS AN ACR FLT Y HVY AT 12 O'CLOCK. THE CREW RPTED THE TFC IN SIGHT. APCH THEN GAVE A HDG OF 230 DEGS FOR SEPARATION. ON THIS HDG, FLT X CROSSED THE CTRLINE OF BOTH RWY 28R AND RWY 28L. TFC WAS OBSERVED AT 12 O'CLOCK, AND A TCASII 'TA' WAS RECEIVED. THE TFC FLASHED HIS LNDG LIGHTS AS FLT X WAS CLRED FOR THE QUIET BRIDGE VISUAL TO RWY 28R. THE OTHER ACFT, ACR FLT Z (B-737) ASKED ABOUT THE TFC, AND WERE TOLD TO 'RPT THE 757 IN SIGHT.' THE 737 DID SO, AND WAS CLRED FOR THE TIP TOE TO RWY 28L. THE 737 WAS GIVEN A SPD OF 180 KTS AND THE 757 WAS TOLD TO SLOW TO 150 KTS TO ALLOW THE 737 TO 'CATCH UP.' WHEN THE 737 WAS 1 MI IN TRAIL AND AT THE SAME ALT, I LOOKED ABACK AND VISUALLY ACQUIRED HIM. THE CTLR ASKED ACR X IF HE HAD THE 737 IN SIGHT, AND HE REPLIED THAT HE DID. AT THE TIME, I WAS WONDERING WHY THE 737 WOULD REMAIN IN THIS HAZARDOUS POS BECAUSE OF WAKE VORTICES (WIND WAS 300 DEGS AT 20 KTS) AT THAT TIME, ATC TOLD ACR X TO MAINTAIN VISUAL SEPARATION FROM THE 737, AS THE 737 PASSED US WITH A 20-30 KT SPD ADVANTAGE. I CONTACTED THE 737 CREW AND THEY TOLD ME THAT THEY UNDERSTOOD THE 'CATCH-UP' TO MEAN 'PASS.' THEY WERE GOING TO PASS, REGARDLESS, TO AVOID THE 757 WAKE. WHILE THE ONUS WAS ON THEM TO MAINTAIN VISUAL AND WAKE SEPARATION, IT APPEARS THAT THIS RESPONSIBILITY WAS TRANSFERRED TO THE 757, WHEN THE OVERTAKE WAS OBVIOUS. WHO'S GOT THE LEAD? WHO GETS VIOLATED FOR LOSING SIGHT/PASSING? VISUALS AT SFO ARE AN AIRSHOW.

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.