Narrative:

We were on approach to sfo runway 28L. From 7000 ft we were given instructions to descend to 3000 ft and slow to 180 KTS. I recall the copilot advising the captain who was flying, to slow down. The captain answered that he could not go down and slow at the same time. The air carrier Y DC10 came from woodside at 4000 ft and crossed from left to right below us. Once he was past us we were directed to descend to 3000 ft. We were cleared for the approach runway 28L and advised that there was a DC10 approaching on runway 28R. My first recollection of air carrier Y was when we came up exactly abreast of him. The captain asked us to keep him in sight. At that point we received a TA on the TCASII. I started to watch him closely and observed him making corrections in our directions. By this time we had slowed to approach speed, configured for landing and final check complete. As air carrier Y continued sliding toward us we moved left of centerline to give him room. At the nearest point I would estimate his proximity at 200 ft to 300 ft at our altitude (approximately 1200 ft). We then received an RA to descend. In complying with the RA we descended considerably below and slowed to 10 KTS below approach speed. We had also moved a good 1/2 mi south of centerline. It appeared that air carrier Y had lined up on runway 28L. While we were complying with the RA, air carrier Y began to move right and accelerated ahead of us. We were stabilized by 500 ft. After we achieved proper spacing, we reacquired centerline and GS. The landing was uneventful. We did not advise tower that we had an RA -- too busy. We received no communication from tower during the entire episode. There was also no communication from air carrier Y.

Google
 

Original NASA ASRS Text

Title: B747 HAD NMAC WITH A DC10 ON THE PARALLEL VISUAL APCH AT SFO RWYS 28L AND 28R.

Narrative: WE WERE ON APCH TO SFO RWY 28L. FROM 7000 FT WE WERE GIVEN INSTRUCTIONS TO DSND TO 3000 FT AND SLOW TO 180 KTS. I RECALL THE COPLT ADVISING THE CAPT WHO WAS FLYING, TO SLOW DOWN. THE CAPT ANSWERED THAT HE COULD NOT GO DOWN AND SLOW AT THE SAME TIME. THE ACR Y DC10 CAME FROM WOODSIDE AT 4000 FT AND CROSSED FROM L TO R BELOW US. ONCE HE WAS PAST US WE WERE DIRECTED TO DSND TO 3000 FT. WE WERE CLRED FOR THE APCH RWY 28L AND ADVISED THAT THERE WAS A DC10 APCHING ON RWY 28R. MY FIRST RECOLLECTION OF ACR Y WAS WHEN WE CAME UP EXACTLY ABREAST OF HIM. THE CAPT ASKED US TO KEEP HIM IN SIGHT. AT THAT POINT WE RECEIVED A TA ON THE TCASII. I STARTED TO WATCH HIM CLOSELY AND OBSERVED HIM MAKING CORRECTIONS IN OUR DIRECTIONS. BY THIS TIME WE HAD SLOWED TO APCH SPD, CONFIGURED FOR LNDG AND FINAL CHK COMPLETE. AS ACR Y CONTINUED SLIDING TOWARD US WE MOVED L OF CTRLINE TO GIVE HIM ROOM. AT THE NEAREST POINT I WOULD ESTIMATE HIS PROX AT 200 FT TO 300 FT AT OUR ALT (APPROX 1200 FT). WE THEN RECEIVED AN RA TO DSND. IN COMPLYING WITH THE RA WE DSNDED CONSIDERABLY BELOW AND SLOWED TO 10 KTS BELOW APCH SPD. WE HAD ALSO MOVED A GOOD 1/2 MI S OF CTRLINE. IT APPEARED THAT ACR Y HAD LINED UP ON RWY 28L. WHILE WE WERE COMPLYING WITH THE RA, ACR Y BEGAN TO MOVE R AND ACCELERATED AHEAD OF US. WE WERE STABILIZED BY 500 FT. AFTER WE ACHIEVED PROPER SPACING, WE REACQUIRED CTRLINE AND GS. THE LNDG WAS UNEVENTFUL. WE DID NOT ADVISE TWR THAT WE HAD AN RA -- TOO BUSY. WE RECEIVED NO COM FROM TWR DURING THE ENTIRE EPISODE. THERE WAS ALSO NO COM FROM ACR Y.

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.