Narrative:

On departure from sfo, under control of ZOA, had a near miss with a light aircraft. After several traffic calls from center to both aircraft, the light aircraft finally saw us and broadcast 'we're on your nose.' we never saw the other aircraft. The traffic had previously asked center 'we're not on a collision course, are we?' the traffic passed by essentially co-altitude and less than 1/4 mi horizontally, estimated by TCASII indications. TCASII announcements were 'traffic, traffic' followed by 'monitor vertical speed,' accompanied by an indication to climb at 1500- 2000 FPM (green band on vsi). Captain (PF) had already started a right turn when center finally gave us a right turn of 20 degrees. Had we waited till then, it would have probably been too late, situation could probably have been avoided by an earlier vector away from traffic. Supplemental information from acn 344432: after receipt of a climb clearance from 5000-10000 ft from ZOA we were given a TA of a light aircraft at 1 O'clock 1 mi opposite direction of flight. We acquired the traffic on TCASII at about 7-8 mi moving from 1 O'clock to 11 O'clock as we closed. The other aircraft saw us and asked ZOA if we were on a collision course? Oak responded 'negatively.' all 3 of us were not able to see the traffic. An order to climb from the TCASII. I banked sharply right, went to full power and climbed at 2200 FPM to avoid the target. After I started the maneuver I heard ZOA issue a 20 degree right turn to avoid traffic, this order was too lake, in my opinion, by a long way. This whole situation could have easily been avoided by prompt center action after we repeatedly asked for the traffic's position. We obviously didn't see it and should have been vectored around it.

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Original NASA ASRS Text

Title: NMAC TURNED INTO A POTENTIAL CONFLICT AS TCASII ALERT STARTS PROVIDING SOME SEPARATION BTWN XING TFC, ABOUT SAME ALT. B747 VERSUS GA ACFT.

Narrative: ON DEP FROM SFO, UNDER CTL OF ZOA, HAD A NEAR MISS WITH A LIGHT ACFT. AFTER SEVERAL TFC CALLS FROM CTR TO BOTH ACFT, THE LIGHT ACFT FINALLY SAW US AND BROADCAST 'WE'RE ON YOUR NOSE.' WE NEVER SAW THE OTHER ACFT. THE TFC HAD PREVIOUSLY ASKED CTR 'WE'RE NOT ON A COLLISION COURSE, ARE WE?' THE TFC PASSED BY ESSENTIALLY CO-ALT AND LESS THAN 1/4 MI HORIZLY, ESTIMATED BY TCASII INDICATIONS. TCASII ANNOUNCEMENTS WERE 'TFC, TFC' FOLLOWED BY 'MONITOR VERT SPD,' ACCOMPANIED BY AN INDICATION TO CLB AT 1500- 2000 FPM (GREEN BAND ON VSI). CAPT (PF) HAD ALREADY STARTED A R TURN WHEN CTR FINALLY GAVE US A R TURN OF 20 DEGS. HAD WE WAITED TILL THEN, IT WOULD HAVE PROBABLY BEEN TOO LATE, SIT COULD PROBABLY HAVE BEEN AVOIDED BY AN EARLIER VECTOR AWAY FROM TFC. SUPPLEMENTAL INFO FROM ACN 344432: AFTER RECEIPT OF A CLB CLRNC FROM 5000-10000 FT FROM ZOA WE WERE GIVEN A TA OF A LIGHT ACFT AT 1 O'CLOCK 1 MI OPPOSITE DIRECTION OF FLT. WE ACQUIRED THE TFC ON TCASII AT ABOUT 7-8 MI MOVING FROM 1 O'CLOCK TO 11 O'CLOCK AS WE CLOSED. THE OTHER ACFT SAW US AND ASKED ZOA IF WE WERE ON A COLLISION COURSE? OAK RESPONDED 'NEGATIVELY.' ALL 3 OF US WERE NOT ABLE TO SEE THE TFC. AN ORDER TO CLB FROM THE TCASII. I BANKED SHARPLY R, WENT TO FULL PWR AND CLBED AT 2200 FPM TO AVOID THE TARGET. AFTER I STARTED THE MANEUVER I HEARD ZOA ISSUE A 20 DEG R TURN TO AVOID TFC, THIS ORDER WAS TOO LAKE, IN MY OPINION, BY A LONG WAY. THIS WHOLE SIT COULD HAVE EASILY BEEN AVOIDED BY PROMPT CTR ACTION AFTER WE REPEATEDLY ASKED FOR THE TFC'S POS. WE OBVIOUSLY DIDN'T SEE IT AND SHOULD HAVE BEEN VECTORED AROUND IT.

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.