Narrative:

On the descent into bna we expected and briefed runway 2L. When we checked in with approach on 118.4 our initial call went unanswered twice. When we did get a response; I didn't recall reading back a runway assignment. On downwind we were switched to final approach on 124.75. The controller turned us shortly afterwards and cleared us for ILS 2R approach; I read back ILS 2L. I immediately saw aircraft Y turning final for runway 2L and I questioned approach which runway we were assigned. My call went unanswered. The TCAS alert went off and I told the first officer (first officer) to hand fly directly toward the airport until she answers; we were lined up with 2C at this time. I called back again after a bunch of other calls were made and she finally cleared us for the visual to 2R. We switched to tower and were cleared to land. The ground controller gave us a phone number to call. At the gate; I called the number and spoke with an ATC manager. He advised me that we had a deviation. I told him I thought we were cleared 2L and he said he would call back when he had a chance to review the tapes. He called back before we pushed and advised me that I did read back 2R initially on 118.2 but read back 2L when cleared for the ILS. He said it was their fault they didn't catch the read back and their manager might call me back for additional information.

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Original NASA ASRS Text

Title: EMB145 and B737 flight crews reported an airborne conflict event while commencing the final approach in a parallel runway environment.

Narrative: On the descent into BNA we expected and briefed runway 2L. When we checked in with approach on 118.4 our initial call went unanswered twice. When we did get a response; I didn't recall reading back a runway assignment. On downwind we were switched to final approach on 124.75. The controller turned us shortly afterwards and cleared us for ILS 2R approach; I read back ILS 2L. I immediately saw Aircraft Y turning final for runway 2L and I questioned approach which runway we were assigned. My call went unanswered. The TCAS alert went off and I told the FO (First Officer) to hand fly directly toward the airport until she answers; we were lined up with 2C at this time. I called back again after a bunch of other calls were made and she finally cleared us for the visual to 2R. We switched to tower and were cleared to land. The ground controller gave us a phone number to call. At the gate; I called the number and spoke with an ATC manager. He advised me that we had a deviation. I told him I thought we were cleared 2L and he said he would call back when he had a chance to review the tapes. He called back before we pushed and advised me that I did read back 2R initially on 118.2 but read back 2L when cleared for the ILS. He said it was their fault they didn't catch the read back and their manager might call me back for additional information.

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.