Narrative:

On arrival into ind we were cleared for the approach. As pm I read back 'turn right 200 degrees maintain 2000 till established cleared the ILS 23 left approach.' just outside racyr; ATC informed us of a low altitude alert and were told to climb back up to 3000 feet. Once there we were re-cleared for the ILS 23 left approach. No further incidents. I would say that fatigue was the primary culprit. When we read back the clearance it should have seemed an unusual alt to intercept at; as the minimum alt at racyr is 2600 ft. Also when I received the clearance there was chatter on guard 121.5 which could have interfered with hearing our clearance correctly. Better rest; clarification of the clearance and acknowledgement by ATC of the read back.

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Original NASA ASRS Text

Title: Air carrier crew on vectors for the IND Runway 23L ILS descended to 2;000 feet; but climb back to 3;000 feet after ATC issued a low altitude alert. Fatigue and a misunderstood descent clearance were factors.

Narrative: On arrival into IND we were cleared for the approach. As PM I read back 'turn right 200 degrees maintain 2000 till established cleared the ILS 23 left approach.' Just outside RACYR; ATC informed us of a low altitude alert and were told to climb back up to 3000 feet. Once there we were re-cleared for the ILS 23 left approach. No further incidents. I would say that fatigue was the primary culprit. When we read back the clearance it should have seemed an unusual alt to intercept at; as the minimum alt at RACYR is 2600 ft. Also when I received the clearance there was chatter on guard 121.5 which could have interfered with hearing our clearance correctly. Better rest; clarification of the clearance and acknowledgement by ATC of the read back.

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.