Air carrier flight crew reported following a false glide path on the ILS 19 approach at ABL; resulting in a CFTT incident.
Synopsis
Air carrier flight crew reported following a false glide path on the ILS 19 approach at ABL; resulting in a CFTT incident.
Narrative
As we were approaching ALB we were on a downwind leg vector of 350 degrees. The weather was hazy with few clouds around 3;000 feet; but VMC. The Tower queried us if we had the airport in sight. The Captain confirmed he saw it to his left and informed the Tower that we had it in sight. We were then cleared to accomplish a visual approach. I continued on 350 degrees to slow the aircraft and begin adding flaps. We also began a descent to 2;000 feet prior to initiating a left base leg. As we were descending we saw indications that we were well above glideslope; which turned out to be a false glideslope. We entered 1;600 into the altitude selector on a dogleg to final of 19. We had the ILS 19 approach loaded and selected to back up our visual approach to 19. We still showed to be considerably high so we selected 1;000 feet. As we approached 1;000 feet we realized the glideslope had been false; as we visually looked low compared to the runway we visually saw. I disconnected the autopilot and flew visually to a normal landing. The Tower also notified [us] right after we realized we were following a false glideslope of a low altitude indication.Cause: Task saturation along with experiencing a false glideslope on a visual approach backed up with an ILS led to descending lower than a desired altitude on an approach.Suggestion: Crews may need to be aware of a false glideslope when approaching ILS 19 at ABL on a left base. I also should extend downwind longer in the future to give more time and recognize a false glideslope more quickly. In hazy conditions with only the pilot monitoring having the runway continually in sight; it would be more prudent to have vectors to a longer final approach.
Second reporter narrative
We were set up on left downwind for 19 going into ALB. After crossing the highest obstacle we reported the field in sight; got cleared for the visual; and began a descent down to 2;000 feet. FO was pilot flying and turned about a 10-mile left base abeam EYMEY and then turned about a 45-degree intercept course to join the localizer around HAUKY. He set 500 in the altitude preselector for the Decision Altitude (DA) and started descending. I saw that he was going to descend below 1;600 feet while still several miles prior to HAUKY; and requested that he level off at 1;600 feet until we intercept and cross HAUKY. At this point we were in green needles and fully configured; ready to run the before landing checklist. I verified that 1;600 was then set into the altitude preselector and the altitude captured; and then proceeded to run the checklist. Upon completion of the checklist I saw that we were in a descent approaching 1;000 feet. I stated that we were too low and need to climb now. PF promptly disconnected the autopilot and started a climb; and we cleared Flight Directors (FDs). I noted that the Horizontal Situation Indicator (HSI) was showing us on the glideslope; which was bad data since we were still pretty far offset from the localizer; and the PF complained he had a poor view of the runway from the right seat. ATC queried that we were setting off a low altitude alert; and we replied that we were making the associated correction and confirmed that the runway was still in sight. The altitude was corrected back to a desirable state and we were in a good position to intercept the proper approach path; so we continued the visual approach and landed with no further issue.Cause: PF was distracted by a bad glideslope indication and followed it down to an undesirably low altitude. PM was distracted running a checklist and did not notice the undesired descent being initiated.Suggestion: Proper adherence to SOP would have both pilots verify changes to the altitude preselector. This allows either pilot to catch and correct a potential mistake before it becomes an issue.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.