EMB-175 flight crew reported they were issued a low altitude alert from ATC due to descending below the glide path on their approach.
Synopsis
EMB-175 flight crew reported they were issued a low altitude alert from ATC due to descending below the glide path on their approach.
Narrative
Descending on the ZZZZZ 4 STAR with FMS set up to land on Runway XXL in accordance with the ATIS; was notified by ZZZ Approach on initial contact that airport was being turned around and to expect to land west. At this point we were approaching ZZZZZ on the STAR. We requested and were cleared for the RNAV Z XYR approach. My First Officer (FO) loaded the new approach in the FMS from ZZZZZ1 he fix where it ties into the STAR. This left us significantly high above the glide path so I selected green FLCH and full speed brakes. I also set the altitude selector to the FAF altitude of 3900 ft. at ZZZZZ2 since we had been cleared for the approach. My FO sent for standard / non-ice ACARS Runway XYR landing data and as he was loading the speeds in the FMS we received STALL PROT ICE SPEEDS EICAS message. At that point I became preoccupied with ensuring my FO resent for STALL PROT ICE SPEEDS and got them loaded in the FMS.I neglected to note that we were approaching the desired flight path at which point I should have selected VNAV on the Guidance Panel. Both my FO and I noticed we were beginning to descend below the path at the same time we received a low altitude alert from ATC. We were VMC and aligned with the runway at that point; so I turned off the autopilot and corrected the flight path. We descended to approximated 5300 ft. between ZZZZZ3 and ZZZZZ4 where minimum altitude is 5600. All remaining crossing restrictions and criteria for a stabilized approach were met and we landed uneventfully.My failure as pilot flying to monitor the aircraft flight path. My FO was already sending for and loading the appropriate STALL PROT ICE SPEEDS in the FMS; so there was no need for me to be overly concerned that the correct approach speeds were loaded. Simply put; I know better than to prioritize anything above flight path management. Lesson learned and a mistake I'll be careful to avoid in the future.
Second reporter narrative
We were originally set up for Runway XXL while descending via ZZZZZ 4 STAR as current ATIS had indicated. Approach ATC then told us the landing flow was being changed and to expect XYR. As soon as I got into the MCDU to change the approach and sequence it from ZZZZZ1 which was already in front of us; and then request landing data for XYR; we got a 'STALL PROTECTION ICE SPEEDS' EICAS message. I had to resend the request. We got the numbers and while cross checking with the Captain; we noticed we were descending below the flight path. Captain immediately disengaged his Autopilot and asked me to clear his Flight Director (FD); since we were already lined up for Runway XYR and he manually leveled off to arrest the descent and return to path. We had gone about 300 ft. below already by then. We continued the approach and landed without any issues. My failure to recognize that we were above glide path for XYR when I loaded the approach and we were close to the airport already.I could have suggested a go-around; at the least; but since I already had everything set up; I did not consider the level of saturation of the pilot in command (PIC) in the crosscheck of the numbers. I have also learned that flight path management is both pilot's' responsibility and can become critical if treated otherwise. This occurrence will not happen again in the future.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.