Narrative:

I was the first officer and I was flying. The aircraft had autopilot and autothrottles engaged throughout until the RA when I disengaged the autopilot. It was night. The weather was very clear with 10 KT winds out of the west. We planned flaps 25 auto brakes 2. We were in LNAV and used flch to change altitudes. We were filed to sfo via the modesto 3 arrival and were expecting the ILS to 28R since we were coming in from the east. We crossed cedes at 11000' and about 250 knots. We were then cleared to archi; which was not on our current route. No mention was made on the ATIS or by the controller to expect the FMS bridge visual to 28R. The captain loaded the 28R RNAV approach. We were cleared to 8000 ft and slowed to 230 KTS. We were asked if we had the airport or the bridge when we were over the east part of the bay. We said we had the airport and the bridge. We were slowed to 210 and cleared the FMS visual. We descended on the profile to 6000 ft we were slowed to 180. We continued to 4000 ft and we were slowed to 160 and we were told not to pass an aircraft on the approach to 28L that was about 3 miles ahead. We had that aircraft on TCAS and visual. We were also told not to pass an aircraft approaching 28L from the south that was already behind us. This was confusing. It also was the aircraft that ended up causing the RA. We continued on profile and descended to 1800. I began to slow to final approach speed of 143 KTS. The aircraft in front of us was always 2 or 3 miles ahead of us. We continued down on profile to 1200 ft where we intercepted the glidepath and localizer to 28R. We were on centerline and glidepath when around 1000 ft we got a traffic traffic amber alert. Shortly there after we got a climb RA. I clicked off the autopilot and began a climb when we got a descend RA. I started to level off and descend when we got a clear of conflict. By now we were off profile and the captain said go-around. He had a visual out his window of the aircraft most of the time. I could not see the aircraft from my seat. We executed a missed approach climbed out to 5000 ft and came back for a normal landing on 28R. One comment is that I did notice a couple of times that all the TCAS symbols would shift or rather rotate about a quarter of an inch left and then return to their original position. This may have been an aircraft specific TCAS problem. I don't know if the aircraft was actually right under us or not but it appeared to be so on TCAS. It would have been helpful to have nd screens with 5 mile range like the 400 has. The controllers could probably do a better job of pairing up aircraft with much different approach speeds if they had better equipment. Putting a 140 or 150 KT heavy airplane slightly behind an aircraft on the parallel runway that is 30 or 40 knots slower can be accomplished with proper spacing. Maybe they need better computers to help them predict how to get aircraft over the threshold at the same time. Maybe they should assign airspeeds to be maintained until a specified fix 5 miles from the airport and inquire what each aircraft's planned final speed will be to help them figure out the spacing. Maybe the monitor should be active all the time at sfo.

Related reports:

Google
 

Original NASA ASRS Text

Title: A large air carrier aircraft executed a go around while on short final to SFO 28R because of a TCAS RA from a smaller aircraft.

Narrative: I was the First Officer and I was flying. The aircraft had autopilot and autothrottles engaged throughout until the RA when I disengaged the autopilot. It was night. The weather was very clear with 10 KT winds out of the west. We planned Flaps 25 auto brakes 2. We were in LNAV and used FLCH to change altitudes. We were filed to SFO via the Modesto 3 arrival and were expecting the ILS to 28R since we were coming in from the east. We crossed Cedes at 11000' and about 250 knots. We were then cleared to ARCHI; which was not on our current route. No mention was made on the ATIS or by the controller to expect the FMS Bridge visual to 28R. The Captain loaded the 28R RNAV approach. We were cleared to 8000 FT and slowed to 230 KTS. We were asked if we had the airport or the bridge when we were over the east part of the bay. We said we had the airport and the bridge. We were slowed to 210 and cleared the FMS visual. We descended on the profile to 6000 FT we were slowed to 180. We continued to 4000 FT and we were slowed to 160 and we were told not to pass an aircraft on the approach to 28L that was about 3 miles ahead. We had that aircraft on TCAS and visual. We were also told not to pass an aircraft approaching 28L from the south that was already behind us. This was confusing. It also was the aircraft that ended up causing the RA. We continued on profile and descended to 1800. I began to slow to final approach speed of 143 KTS. The aircraft in front of us was always 2 or 3 miles ahead of us. We continued down on profile to 1200 FT where we intercepted the glidepath and localizer to 28R. We were on centerline and glidepath when around 1000 FT we got a traffic traffic amber alert. Shortly there after we got a climb RA. I clicked off the autopilot and began a climb when we got a descend RA. I started to level off and descend when we got a clear of conflict. By now we were off profile and the Captain said go-around. He had a visual out his window of the aircraft most of the time. I could not see the aircraft from my seat. We executed a missed approach climbed out to 5000 FT and came back for a normal landing on 28R. One comment is that I did notice a couple of times that all the TCAS symbols would shift or rather rotate about a quarter of an inch left and then return to their original position. This may have been an aircraft specific TCAS problem. I don't know if the aircraft was actually right under us or not but it appeared to be so on TCAS. It would have been helpful to have ND screens with 5 mile range like the 400 has. The controllers could probably do a better job of pairing up aircraft with much different approach speeds if they had better equipment. Putting a 140 or 150 KT heavy airplane slightly behind an aircraft on the parallel runway that is 30 or 40 knots slower can be accomplished with proper spacing. Maybe they need better computers to help them predict how to get aircraft over the threshold at the same time. Maybe they should assign airspeeds to be maintained until a specified fix 5 miles from the airport and inquire what each aircraft's planned final speed will be to help them figure out the spacing. Maybe the monitor should be active all the time at SFO.

Data retrieved from NASA's ASRS site as of April 2012 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.