Air carrier crew reported an unstabilized approach where the flight was low on the final approach profile due to an incorrect altimeter setting. The Captain identified the low visual profile and regained the glide slope and landed normally.
Synopsis
Air carrier crew reported an unstabilized approach where the flight was low on the final approach profile due to an incorrect altimeter setting. The Captain identified the low visual profile and regained the glide slope and landed normally.
Narrative
On about a 4 mile final into CMH RNAV Y Runway 10L I broke out of the clouds and noticed a discrepancy in the Glide Path (GP) vs PAPI. I was showing on GP but 3 red on the PAPI. I then noticed we seemed low and that our altitude was not matching with what the RA should be. To rectify the situation I disconnected the Auto pilot (AP); leveled off the descent; and got myself back on two white; two red PAPI. Then I asked the First Officer (FO) to turn off my Flight Director (FD). We landed normally and I wondered if it was a wrong altimeter setting that might have caused the discrepancy. Sure enough; we had 29.98 set and the actual setting was 29.78.Suggestions: It was go home leg 3 of day 5 of a nearly 30 hr trip. We were tired and misheard/misread the altimeter setting from Approach and the ATIS. I knew the ceilings weren't too low in CMH so I wasn't too concerned at the time. I realize now how dangerous that situation could have been and need to be a much better judge of my own and my FO's potential fatigue and mental acuity. In the future I will be much more stringent in my Confirm; Activate; Monitor; Intervene (CAMI) and approach set up.
Second reporter narrative
During initial descent into CMH; I was Pilot Monitoring (PM) and the Captain was Pilot Flying (PF). Center gave us a decent clearance and the altimeter setting at the field. During descent the Captain asked if the altimeter was 29.98 and I confirmed in the positive. I had misheard what ATC said and gave a false altimeter setting without verifying. In reality the altimeter setting was 29.78; this caused the plane to be indicating higher than actual altitude by approximately 200 ft. The field was overcast at 2;700 ft; once we broke out we saw the PAPIs indicating 3 red and one white and the plane appearing to be lower than the usual site picture. Once this was noticed the Captain took off auto-pilot and requested the flight director to be turned off. The plane landed without any further incidents.Suggestions: The best time to prevent this from happening in the future is during the decent checklist. In the future I'm going to make sure I have the most recent ATIS pulled up on the Multipurpose Control Display Unit (MCDU) while I read the altimeter verify line every time during the descent checklist; and not just verify that they are matching but ensure that the correct setting is being put in. I'm going to make a habit to point as well; similar to how I do when verifying that the landing data is set and when altitudes are set.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.