Narrative:

While on vectors for the ILS xx we received the ATIS which reported 3;300 scattered with several broken/overcast layers above; 2.5 miles visibility; with light rain/mist. We were given a heading to intercept the localizer and told to descend to 2;700 ft. This was a distraction as the two altitudes depicted for the approach were 3;000 and 2;400 ft. As we intercepted the localizer I noticed that the glide slope had captured; the flight director was indicating properly and we had no flags. We both checked this as aircraft glide slope had problems in the past but it had always had flags when it did not operate properly. We initially did not notice that we were descending well before the actual glide slope intercept point. I called that the glide slope had captured and expected the copilot to crosscheck that with his instruments; which he apparently did not. As we descended approach called with a low altitude alert and told us to climb back to 2;700 ft; which we did. Thinking that we had captured a false glide slope I watched the needles as we started our climb and the glide slope indicators did not move from the on glide slope position. Once we were back on altitude we realized we were still outside the marker; checked the copilot's instruments; which appeared to be working and continued the approach using those. This decision was made in part based on the ATIS weather; which as it turned out was not nearly as good as they said. Had we known that we would have missed and tried an RNAV. We continued with a higher than normal workload and finally broke out at about 600 ft. The next day the copilot said he thought we had landed without a clearance. I cannot be sure if he was talking to approach or tower and I do not remember approach switching us over. I believe contributing factors were: 1. The copilot; while type rated in the aircraft has very little experience particularly in abnormal/weather conditions and needs to be told what to do and then is fairly slow in getting things done. We did not have as much situational awareness as was possible on the intercept as he was slow getting the FMS set up. In abnormal situations he gets tunnel vision to a certain extent and things get missed - like crosschecking and finishing checklists. That being said it is my responsibility to get that done and I spent too much time trying to figure out what was wrong and not enough making sure he did his job. 2. I have never seen a glide slope that was not working properly give no indications. The autopilot and flight director both followed the indicator as if everything was normal and no flags were present. 3. The ATIS weather was nowhere near actual weather. Conclusions [are:] 1. The decision to continue the approach (based on location on the approach; weather; and passenger concerns) was wrong. Considering that the copilot was weak (actually a good one would probably have insisted on going around) and the aircraft situation; the proper decision would have been to go missed. 2. Better crew communication needs to be readdressed to insure all functions are completed in a timely manner. I have been spoiled with many years of well trained copilots with which CRM skills are second nature - this is not the case here. 3. More training in the use of and philosophy of the FMS is needed by the copilot. I have tried to get this accomplished before but since he is also the mechanic he does not see the need to spend time improving his piloting skills.

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Original NASA ASRS Text

Title: A Falcon 10 Captain's ILS failed without an instrument warning while conducting an IMC approach. The First Officer did not alert the Captain about his position; low on the glide slope and ATC declared a low altitude alert with a climb command.

Narrative: While on vectors for the ILS XX we received the ATIS which reported 3;300 scattered with several broken/overcast layers above; 2.5 miles visibility; with light rain/mist. We were given a heading to intercept the localizer and told to descend to 2;700 FT. This was a distraction as the two altitudes depicted for the approach were 3;000 and 2;400 FT. As we intercepted the localizer I noticed that the glide slope had captured; the flight director was indicating properly and we had no flags. We both checked this as aircraft glide slope had problems in the past but it had always had flags when it did not operate properly. We initially did not notice that we were descending well before the actual glide slope intercept point. I called that the glide slope had captured and expected the Copilot to crosscheck that with his instruments; which he apparently did not. As we descended Approach called with a low altitude alert and told us to climb back to 2;700 FT; which we did. Thinking that we had captured a false glide slope I watched the needles as we started our climb and the glide slope indicators did not move from the on glide slope position. Once we were back on altitude we realized we were still outside the marker; checked the Copilot's instruments; which appeared to be working and continued the approach using those. This decision was made in part based on the ATIS weather; which as it turned out was not nearly as good as they said. Had we known that we would have missed and tried an RNAV. We continued with a higher than normal workload and finally broke out at about 600 FT. The next day the Copilot said he thought we had landed without a clearance. I cannot be sure if he was talking to Approach or Tower and I do not remember Approach switching us over. I believe contributing factors were: 1. The Copilot; while type rated in the aircraft has very little experience particularly in abnormal/weather conditions and needs to be told what to do and then is fairly slow in getting things done. We did not have as much situational awareness as was possible on the intercept as he was slow getting the FMS set up. In abnormal situations he gets tunnel vision to a certain extent and things get missed - like crosschecking and finishing checklists. That being said it is my responsibility to get that done and I spent too much time trying to figure out what was wrong and not enough making sure he did his job. 2. I have never seen a glide slope that was not working properly give no indications. The autopilot and flight director both followed the indicator as if everything was normal and no flags were present. 3. The ATIS weather was nowhere near actual weather. Conclusions [are:] 1. The decision to continue the approach (based on location on the approach; weather; and passenger concerns) was wrong. Considering that the Copilot was weak (actually a good one would probably have insisted on going around) and the aircraft situation; the proper decision would have been to go missed. 2. Better crew communication needs to be readdressed to insure all functions are completed in a timely manner. I have been spoiled with many years of well trained Copilots with which CRM skills are second nature - this is not the case here. 3. More training in the use of and philosophy of the FMS is needed by the Copilot. I have tried to get this accomplished before but since he is also the mechanic he does not see the need to spend time improving his piloting skills.

Data retrieved from NASA's ASRS site as of April 2012 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.