Commercial Fixed Wing
Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP)
Workload; Distraction; Human-Machine Interface
Deviation - Altitude Excursion From Assigned Altitude; Deviation / Discrepancy - Procedural Clearance; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter CFTT / CFIT; Inflight Event / Encounter Unstabilized Approach; Inflight Event / Encounter Weather / Turbulence
Flight Crew Overcame Equipment Problem
Human Factors
While coming into ZZZ we checked the weather and the ceilings were not quite what we needed for the RNAV XX. We had plenty of gas and decided to ask for a hold. After holding we were informed of an aircraft that had broken out right at minimums. We decided to start the approach. We were cleared to cross the Initial Approach Fix at or above 3;000 ft. After crossing the fix the FO (First Officer) pilot flying; set the new altitude for 2;100 ft. which was the lowest altitude on the segment for the final app fix. After leveling off the First Officer then set 800 ft. for the MDA. Prior to the FAF I suggested flaps 45 instead of flaps 22 so we could get a lower deck angle and see the field better. He agreed so I was heads down while getting the new numbers. I was also told to contact Tower and after checking on he mentioned to check our altitude because he saw us low. At that point the FO was already correcting and we returned to the previous altitude promptly. This was corrected before the FAF so we didn't see a reason to terminate the approach. Not properly monitoring and heads down in a critical phase of flight. I shouldn't have suggested the late flap change. If I hadn't I could have noticed the FO descending early before ATC did. Next time I will keep what we have and after a missed approach I could change and try again.
Air carrier Captain reported altitude excursion during initial approach due to his failure to properly monitor flying pilot. Altitude excursion was corrected and flight completed a safe landing.