Date: 202001
Local time of day: 1801-2400
Location: SJC.Airport, CA
Flight conditions: VMC
Light: Night
Aircraft: B737-800
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Initial Approach
Airspace: Class E NCT
ATC / advisory: TRACON NCT
Reporter organization: Air Carrier
Reporter function: Pilot Not Flying; Captain
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Communication Breakdown; Situational Awareness
Second reporter function: First Officer; Pilot Flying
Anomaly: Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural Clearance; Inflight Event / Encounter CFTT / CFIT
Detector: Automation Aircraft Terrain Warning
When detected: In-flight
Result: Flight Crew Took Evasive Action; Flight Crew FLC Overrode Automation; Flight Crew Became Reoriented
Contributing factors: Environment - Non Weather Related; Human Factors; Procedure
Primary problem: Human Factors

Narrative: On our arrival into SJC at approximately XA:40PM with FO flying; NorCal approach cleared us down to 5;100 feet flying over low; unlit mountainous terrain just east of coast. With VMC conditions prevailing; NorCal asked if we would like a visual approach. With the airport in sight; the FO indicated yes he would. The aircraft (Nav Radios and FMC) was set up for the ILS 30L approach for back up guidance and had been appropriately briefed. We set 2;700 feet in the altitude alerter window for the crossing restriction at HIVAK (GS Intercept) intersection as back up. The FO asked for a Leg Intercept to HIVAK. While I was head down executing Leg Intercept and then looking at IPad to confirm Tower Frequency and tune radios; the FO had smoothly initiated a Vertical Speed descent that I did not notice or feel in the seat of the pants. A Terrain GPWS Alert got my full attention. With a delayed response in the right seat; I took control of the aircraft and immediately executed an escape maneuver to ascend free of terrain. When well clear of terrain; configured aircraft; reestablished stable approach; and made uneventful landing.Especially in critical phases of flight (below 10;000 and sterile); great example of the need for communication Between Pilot Monitoring and Pilot Flying.I've done this arrival countless times and am very familiar. In the Debrief I learned the FO was not familiar. Although I had brought up the terrain and how dark it was to the FO as we approached; I could have been briefed up better. Additionally; I do believe NorCal kind of baited Pilot Flying with a Visual Approach Clearance at night while still over unlit terrain.In the future; especially at night; the RNAV Z to 30L would have been a much better option and prudent.


Second narrative: During our initial descent into SJC; we received a GPWS alert followed by a warning. The recovery was initiated immediately by the Captain (PM). He followed the correct procedure and complied with this warning. We then exchanged controls and the rest of the approach was uneventful. I was the pilot flying. During the descent into SJC; we were cleared to descend to 5;100 feet. It was very dark and it was hard to see the surrounding mountains. I checked my VSD as well as the highest peak in the area and clearance was showing at 4;100 feet. Due to the long day and night flying; I was more comfortable doing the ILS 30L into SJC with vectors to final. However; we agreed on accepting a visual approach. We began the downwind leg as well as a gradual descent from 5;100 feet to be at the final approach fix at 2;700 feet. Upon beginning the descent in vertical speed; we received a GPWS alert for terrain ahead. I immediately disconnected the autopilot and leveled off the aircraft. Within a few seconds; we received a GPWS warning to pull up. The Captain took over the controls; recovered promptly and after climbing back up to roughly 5;000 feet; he initiated the descent back into SJC. We exchanged controls and I completed the approach and landed uneventfully.Whenever flying at night surrounded by terrain; I will insist in requesting an ILS or RNP approach to provide an additional margin of safety and protection from the surrounding terrain. I will also do a better job at communicating with my Captain that we have initiated a descent and to verify that what I'm doing looks correct; but most importantly; safe. The next time I hear a GWPS alert; I will respond more proactively and will initiate a climb more promptly without hesitation.


Synopsis: B737-800 flight crew reported a CFTT event during a night visual approach to SJC airport.