A320
Flight Crew Last 90 Days 93; Flight Crew Total 6059; Flight Crew Type 46
Situational Awareness
Aircraft Equipment Problem Less Severe; Inflight Event / Encounter Weather / Turbulence
Air Traffic Control Issued Advisory / Alert; Air Traffic Control Issued New Clearance; Flight Crew Took Evasive Action
Aircraft; Weather
We were being vectored for an ILS approach to 12R in SJC. The conditions where IMC with moderate turbulence. The NorCal controller cleared us to descend to 5100 and cleared us direct to JESEN intersection. While level we received a GPWS terrain/terrain. I was the pilot flying so I performed the terrain escape maneuver per [company procuedures] and climbed approximately 900 feet. ATC was notified and she responded that the Minimum Vectoring Altitude for the area we were [at] was 5100 feet; she then told us to descend to 4700 feet so we descended back down to 4700 feet and were given a heading of 310 and continued vectoring for the approach and landed without incident.
At 5100 while being vectored for an approach to RWY 12R we had a GPWS warning. Night IMC; and the approach plate showed MSA of 5600. We performed terrain escape maneuver to silence the warning then advised ATC. Maximum altitude was about 6000 feet (climb from 5100). Moderate turbulence at the time of the occurrence with updrafts and downdrafts. ATC responded that minimum vectoring altitude in that sector was 5100 feet and vectored us to final. I suggested the occurrence might have been caused by the moderate turbulence. Total time of the event was approximately 2 minutes. Location of the event was approximately N37.07 W121.82; having been cleared direct JESEN prior to JAWWS.
A320 flight crew experiences a terrain warning at 5100 feet south of SJC in night IMC; while being vectored by NCT. Evasive action is taken by the crew; climbing to 6000 feet although NCT states that 5100 feet is the correct MVA for that area. The Captain believes the turbulence may have been a factor in the false terrain warning.