AN AIRBUS ON A VISUAL APCH TO SFO PERFORMS A GAR AT ABOUT 300 FT AGL. SFO TWR ASKS WHY THE GAR.

Narrative

DURING BIG SUR ARR TO SFO; LEVEL AT 4000 FT; BAY APCH ASKED US IF RWY IN SIGHT. REPLY WAS AFFIRMATIVE; AND BAY APCH CLRED US TIP TOE VISUAL TO RWY 28L. AT TURN POINT FOR HDG TO LOC INTERCEPT; BAY APCH CHANGED CLRNC TO QUIET BRIDGE VISUAL FOR RWY 28R. OTHER ACFT; AFTER ACKNOWLEDGING OUR ACFT IN SIGHT; WAS CLRED VISUAL TO RWY 28L AND TO MAINTAIN VISUAL ON OUR ACFT WHICH WAS AHEAD OF THE AIRBUS. CAPT SAW THE OTHER ACFT BEHIND AND L DURING DSCNT. INSIDE OF THE SAN MATEO BRIDGE ON GLIDE PATH AND ALIGNED TO THE R OF RWY AND LOC; CAPT SAW THE OTHER ACFT OVERTAKING US AND EXTREMELY CLOSE. TWR CLRED US TO LAND RWY 28R. AT 1500 FT AND BELOW; TCASII TA ALERTED 3 TIMES WITH A TFC RESOLUTION TO DSND. WE WERE APPROX 300 FT AGL AND OTHER ACFT WAS ALMOST ABEAM. CAPT COULD SEE THE ACFT WAS HIGHER AND ABOVE US; EXTREMELY CLOSE. THE OTHER ACFT PERFORMED A GAR AND WE LANDED. TWR ASKED THE REASON FOR GAR BUT WE WERE UNABLE TO HEAR THE REPLY. CAPT NOTED HE WAS ABLE TO SEE COCKPIT OF THE OTHER ACFT ON SHORT FINAL. VISUAL APCHS TO CLOSE PROX PARALLEL RWYS ARE A CONCERN.