Commercial Fixed Wing
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 240; Flight Crew Total 18000; Flight Crew Type 9500
Aircraft Equipment Problem Less Severe; Deviation - Altitude Excursion From Assigned Altitude
Air Traffic Control Issued Advisory / Alert; Aircraft Equipment Problem Dissipated; Flight Crew Took Evasive Action
Aircraft
We were descending through 11;200 approaching LOZIT on the golden gate arrival to SFO. We had a TCAS RA. The target was 200 FT below us. We followed the guidance to 13;000 FT when the oral and visual stopped. The target stayed with us at 200 FT below our altitude. At 13;000 FT it disappeared. We did not see an airplane visually; nor did we see a TCAS target near us prior to the RA sounding. We immediately notified NORCAL of our TCAS RA climb. They told us that they did not have an aircraft on their scope.
During descent into SFO on the GOLDN1 Arrival we were cleared to cross LOZIT at 11;000 FT. The Captain was flying with the autopilot on in a VNAV PATH descent. Descending through 12;000 FT we got a TRAFFIC TA and a pop up red target on the HSI. The TA was followed immediately by a CLIMB RA. The Captain disconnected the autopilot and initiated a climb per the RA. TCAS then commanded an INCREASE CLIMB RA. I called OAK Center and informed them of our RA and resultant climb. The Controller told us that he had no other traffic in the area. At 13;000 FT the target suddenly dropped off our HSI without downgrading to a yellow or white target. We then re-initiated a decent but were unable to comply with the 11;000 FT crossing restriction at LOZIT. The target on our HSI's remained with us at our exact location and altitude throughout the incident. We believe it was a phantom target and not an actual aircraft that triggered the RA. The rest of the flight was normal.
Air Carrier flight crew experiences a TCAS RA descending through 12;000 FT and climbs to comply with the RA. Target is co-located and at or slightly below the reporter's aircraft and climbing with it until it disappears at 13;000 FT.