Narrative:

We were cleared to track the localizer to [runway] 5R; descend to 3;100 ft MSL; maintain 180 KIAS until nurve (glideslope intercept). [We were] cleared for the ILS contact tower. The first officer 'bowtied' the 180 KIAS while the hollow magenta ball was still up above 200 KIAS and he was using 'vert speed' down that was getting us to 3;100 ft somewhat early but we were told to carry the high speed so it was not a big concern. Slats were extended and we had flaps 15 by the time we hit nurve. Nurve was a point where a lot of things were going to happen. (I.e. Further configuration and start slowing to approach speed). We were also just getting through the cloud deck at that point and because of the low (both angle and lumens) light and generally grey lighting it was not easy to see all the details of the airport. We intercepted the glideslope; and started slowing and configuring. I was watching the speed closely because I wanted to back the first officer up if the hollow magenta ball became active and he missed that event--he caught it and everything looked normal while we worked toward a stable approach speed. As I was accomplishing the configuration changes I was pretty much heads down to make sure we were getting the speed right and were on the ILS guidance. Did not know anything was abnormal until tower called and said we had tripped their altitude alerting system. I think we had just passed 1;000 ft AGL. Sure enough it was 4 red lights on the PAPI! But the glideslope still showed us on glideslope. The first officer; flying manually; quickly broke the descent rate to get on the PAPI; stabilized by 500 ft and we continued for a safe landing. The whole time the glideslope indicator in the cockpit did not show much deviation at all; never more than 1/3 of a dot. And we confirmed that we still had a good lock on i-oqv. As we landed we noted that there was an md-11 holding short of runway 5R; and I think it is very likely that interfered with the ILS guidance. Departing aircraft have to tune i-oqv for departure. I wrote the event up in the logbook so maintenance could see if there had been a problem with our equipment but I don't know if they found anything. I called indy tower to thank them and see if there had been any problems with their systems to which they advised their systems all showed normal. We never got any aural warnings from onboard systems; glideslope; terrain; etc. I suspect that the aircraft at the hold line (which we noted on our subsequent departure was well past the ILS hold line) interfered somehow with the ILS guidance. From a CRM/human factors standpoint I am very concerned about this event especially in light of recent training cycle and a conversation with one of our check airmen who is deeply involved with CRM training. We both discussed the advisability of being fully configured much sooner than 'the feather' so the pilot not flying can monitor all available inputs as opposed to being 'heads down' configuring and running checklists and changing radio frequencies; etc. At this crucial point. If those actions are paced more evenly the pilot not flying will have a better chance of noting deviations. It also makes the bio feedback of multiple speed and configuration changes a better indicator of 'something not right' if they are not all happening at once. We all try to fly as efficiently as possible but the additional gas spent by configuring a little further out is a cheap insurance policy so the pilot not flying can perform the duties required.

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Original NASA ASRS Text

Title: When ATC advised the flight crew of Widebodied cargo jet of a low altitude alert while flying the ILS to visual conditions at IND the jet descended below the overcast and the crew noted four red PAPI lights although their glideslope indicator showed them within acceptable limits. When they corrected their path per the PAPI the glideslope indicator failed to reflect their altered vertical path. Although the reporters' noted an MD11 parked in the vicinity of the glideslope transmitter they opted to write up the anomalous glideslope indication.

Narrative: We were cleared to track the localizer to [Runway] 5R; descend to 3;100 FT MSL; maintain 180 KIAS until NURVE (glideslope intercept). [We were] cleared for the ILS contact Tower. The First Officer 'bowtied' the 180 KIAS while the hollow magenta ball was still up above 200 KIAS and he was using 'vert speed' down that was getting us to 3;100 FT somewhat early but we were told to carry the high speed so it was not a big concern. Slats were extended and we had flaps 15 by the time we hit NURVE. NURVE was a point where a lot of things were going to happen. (i.e. further configuration and start slowing to approach speed). We were also just getting through the cloud deck at that point and because of the low (both angle and lumens) light and generally grey lighting it was not easy to see all the details of the airport. We intercepted the glideslope; and started slowing and configuring. I was watching the speed closely because I wanted to back the First Officer up if the hollow magenta ball became active and he missed that event--he caught it and everything looked normal while we worked toward a stable approach speed. As I was accomplishing the configuration changes I was pretty much heads down to make sure we were getting the speed right and were on the ILS guidance. Did not know anything was abnormal until Tower called and said we had tripped their altitude alerting system. I think we had just passed 1;000 FT AGL. Sure enough it was 4 red lights on the PAPI! but the glideslope still showed us on glideslope. The First Officer; flying manually; quickly broke the descent rate to get on the PAPI; stabilized by 500 FT and we continued for a safe landing. The whole time the glideslope indicator in the cockpit did not show much deviation at all; never more than 1/3 of a dot. And we confirmed that we still had a good lock on I-OQV. As we landed we noted that there was an MD-11 holding short of Runway 5R; and I think it is very likely that interfered with the ILS guidance. Departing aircraft have to tune I-OQV for departure. I wrote the event up in the logbook so Maintenance could see if there had been a problem with our equipment but I don't know if they found anything. I called Indy Tower to thank them and see if there had been any problems with their systems to which they advised their systems all showed normal. We never got any aural warnings from onboard systems; glideslope; terrain; etc. I suspect that the aircraft at the hold line (which we noted on our subsequent departure was well past the ILS hold line) interfered somehow with the ILS guidance. From a CRM/Human Factors standpoint I am very concerned about this event especially in light of recent training cycle and a conversation with one of our check airmen who is deeply involved with CRM training. We both discussed the advisability of being fully configured much sooner than 'the feather' so the pilot not flying can monitor all available inputs as opposed to being 'heads down' configuring and running checklists and changing radio frequencies; etc. at this crucial point. If those actions are paced more evenly the pilot not flying will have a better chance of noting deviations. It also makes the bio feedback of multiple speed and configuration changes a better indicator of 'something not right' if they are not all happening at once. We all try to fly as efficiently as possible but the additional gas spent by configuring a little further out is a cheap insurance policy so the pilot not flying can perform the duties required.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.