A319
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 180; Flight Crew Total 11667; Flight Crew Type 7658
Situational Awareness
Deviation - Altitude Excursion From Assigned Altitude; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter CFTT / CFIT; Inflight Event / Encounter Fuel Issue
Flight Crew Became Reoriented; Flight Crew Returned To Clearance
Environment - Non Weather Related; Human Factors
On the River Visual 19 to DCA we were issued a 'low altitude alert' by Reagan Tower. We were approximately 4 DME DCA at approximately 1;000 feet. The Captain immediately leveled off until we joined a 3:1 glide path and landed without incident.After thoroughly debriefing the event; it was determined that two issues contributed to the low altitude:While on the FRDMM 3 RNAV arrival; we were issued an unanticipated hold at PLDGE intersection. After 30 minutes of holding; we were cleared inbound and; almost immediately; were issued a 90 degree vector off course. We declared 'minimum fuel'. When we joined the arrival; the FMGC showed us landing with 50 minutes of fuel. The additional discussion about our fuel state distracted us both from focusing exclusively on the approach.It was the first time that either of us had flown the River Visual approach in some time. The approach was conducted at nighttime. Due to these factors; the majority of our time was spent 'outside the aircraft' so as to avoid the prohibited area and locate Runway 19. This extra 'outside' time reduced our altitude awareness.
A319 First Officer reported receiving a low altitude alert from ATC on a night visual approach to DCA.