Narrative:

Air carrier medium large transport departed sfo on offshore 1 departure. Told to maintain 4000' and head 250 degrees. Traffic called at 12 O'clock, 4 mi at 4500' by departure control. We were looking directly into the afternoon sun and could not see the traffic. The other traffic called us in sight (an small aircraft was the other aircraft). Departure cleared us to climb to 13000'. We declined the clearance and just then saw the small aircraft at approximately 1/2 mi at our 10 O'clock position heading northbound. If we had initiated the climb when cleared and not seen the other aircraft a collision most probably would have been unavoidable. This is one of the fallacies of the 'see and avoid' concept. The other aircraft could only maintain sep visually if our flight path did not change. West/O my seeing the other aircraft I could not be assured of not hitting him. With my climb rate of 3-4000' per min and speed of 250 KTS the other aircraft would have had great difficulty in avoiding me even if he notice my climb immediately. The change in flight path should only be given to the aircraft seeing the other aircraft, not the blind one.

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Original NASA ASRS Text

Title: ACR MLG REFUSED CLRNC TO CLIMB THROUGH THE ALT OF REPORTED VFR GA SMA TRAFFIC UNTIL TRAFFIC WAS SIGHTED.

Narrative: ACR MLG DEPARTED SFO ON OFFSHORE 1 DEP. TOLD TO MAINTAIN 4000' AND HEAD 250 DEGS. TFC CALLED AT 12 O'CLOCK, 4 MI AT 4500' BY DEP CTL. WE WERE LOOKING DIRECTLY INTO THE AFTERNOON SUN AND COULD NOT SEE THE TFC. THE OTHER TFC CALLED US IN SIGHT (AN SMA WAS THE OTHER ACFT). DEP CLRED US TO CLB TO 13000'. WE DECLINED THE CLRNC AND JUST THEN SAW THE SMA AT APPROX 1/2 MI AT OUR 10 O'CLOCK POS HDG NBND. IF WE HAD INITIATED THE CLB WHEN CLRED AND NOT SEEN THE OTHER ACFT A COLLISION MOST PROBABLY WOULD HAVE BEEN UNAVOIDABLE. THIS IS ONE OF THE FALLACIES OF THE 'SEE AND AVOID' CONCEPT. THE OTHER ACFT COULD ONLY MAINTAIN SEP VISUALLY IF OUR FLT PATH DID NOT CHANGE. W/O MY SEEING THE OTHER ACFT I COULD NOT BE ASSURED OF NOT HITTING HIM. WITH MY CLB RATE OF 3-4000' PER MIN AND SPD OF 250 KTS THE OTHER ACFT WOULD HAVE HAD GREAT DIFFICULTY IN AVOIDING ME EVEN IF HE NOTICE MY CLB IMMEDIATELY. THE CHANGE IN FLT PATH SHOULD ONLY BE GIVEN TO THE ACFT SEEING THE OTHER ACFT, NOT THE BLIND ONE.

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.