Narrative:

Flying near frg; we got a yellow TCAS target with no altitude given. We were aware we were low over an airport and scanned the area. The target eventually disappeared and we assumed it was a false return. The captain (pilot monitoring) happened to glance over his left shoulder and gave a startled exclamation and informed me that we came very close to a drone. We did see the yellow target reappear on TCAS with no altitude for a moment after that. He then reported to ATC; who asked for details (it was black and green). It was already behind us at this point and no further action was taken in regards to aircraft operation. I personally never saw the drone; only the TCAS target so I'm unable to say how close we really came. I'm confident we did everything we could to mitigate the risk. The appearance on TCAS was fast and intermittent. Given the lack of altitude information it made it harder to see where to look. After we'd reported the issue to ATC and left the proximity; we could here ATC warn other aircraft in the vicinity; but we never heard anyone else say anything and we switched frequencies soon after.

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Original NASA ASRS Text

Title: An Air carrier pilot reported a NMAC with a Drone.

Narrative: Flying near FRG; we got a yellow TCAS target with no altitude given. We were aware we were low over an airport and scanned the area. The target eventually disappeared and we assumed it was a false return. The Captain (Pilot Monitoring) happened to glance over his left shoulder and gave a startled exclamation and informed me that we came very close to a drone. We did see the yellow target reappear on TCAS with no altitude for a moment after that. He then reported to ATC; who asked for details (it was black and green). It was already behind us at this point and no further action was taken in regards to aircraft operation. I personally never saw the drone; only the TCAS target so I'm unable to say how close we really came. I'm confident we did everything we could to mitigate the risk. The appearance on TCAS was fast and intermittent. Given the lack of altitude information it made it harder to see where to look. After we'd reported the issue to ATC and left the proximity; we could here ATC warn other aircraft in the vicinity; but we never heard anyone else say anything and we switched frequencies soon after.

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.