Air Carrier flight crew reported receiving an ATC low altitude alert during approach. Flight crew climbed and reintercepted the glideslope and continued to a safe landing.
Synopsis
Air Carrier flight crew reported receiving an ATC low altitude alert during approach. Flight crew climbed and reintercepted the glideslope and continued to a safe landing.
Narrative
ATC issued a low altitude alert during base leg while maneuvering for a visual approach to Runway XXR at ZZZ on Day. On a flight from ZZZ1 to ZZZ; we planned for a visual approach backed up by the RNAV RNAV (GPS)Y XXR approach. As Captain; as pilot flying; I planned to intercept the glide path using VNAV about 5 miles from runway at 1;500 ft. AFE (ZZZZZ); and the published altitude for ZZZZZ is 7;760 ft. ATC cleared the aircraft for a visual approach on the downwind leg after the crew responded field in sight when prompted. ATC directed us to call base turn. We descended from 9;000 ft. to 7;700 ft.; and the base turn was initiated abeam ZZZZZ; 4.8 nm from the runway. When the base turn was called; ATC responded 'perfect; ...'The aircraft was in level flight on base turn to intercept extended centerline of Runway XXR. LNAV was engaged for intercept; and the Mode Control Panel (MCP) altitude was set at 7;700 ft. The aircraft GPWS announced '1;000'; and about the same time ATC issued an altitude alert. There is gradually rising terrain north of the airport; that continues to rise north of ZZZZZ. Winds were from the South. After receiving the low altitude alert from ATC; I announced a climb; and the pilot monitoring (PM) jointly said climb. I set a higher altitude in MCP; 8;700 ft.; remained automated; and used FLCH to climb. The PM assisted with the climb to a higher altitude. We intercepted the glide path from a higher altitude using the ZZZZZ1 (Final Approach Fix) published altitude of 8;700 ft. in the MCP altitude. The approach continued uneventfully using VNAV approach procedures; and Flaps 25. Possible contributing factors include gradually rising terrain not fully accounted for; wind at altitude that blew aircraft north of the planned flight path; and expediting an approach using visual procedures rather than fly a published RNAV RNP Approach with an arcing base leg. Suggestion: fly published RNAV RNP Approach with an arcing base leg. Pay more attention to sloping terrain around airport.
Second reporter narrative
During a left base leg turn on a visual approach to ZZZ Runway XXR we received a 'low alt alert' and 'check altimeter' from ATC. This occurred on Date. My role during this event was pilot monitoring (PM). The plan was to conduct a visual approach backed up by the RNAV (GPS)Y Runway XXR and intercept the glide path using VNAV. With the airfield in sight we were cleared for the visual by ATC. We were level in the downwind at 9000 ft. and put 7700 ft. in the Mode Control Panel (MCP) to start our descent in preparation for the visual approach. As we were on a left base and level at 7700 ft.; we received a low altitude alert from ATC. We had no indications in the cockpit that I recall and the pilot flying immediately climbed to 8700 ft. with me backing him up and verifying altimeter settings; (which were set correctly). After climbing to 8700 ft.; we continued the approach to final with no issue in the landing phase. The pilot flying (PF) never de-automated and maintained precise control of the aircraft throughout the event.After discussing the event with the PF; we both attributed the situation to the gently rising terrain to the north and the south winds blowing our flight path more north more than we realized. This could have been avoided by flying the RNAV RNP Approach with the arching base leg or maintaining 8700 ft. until established on final. Also identifying the sloping terrain in our briefing would have increased our awareness.
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Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.