Narrative:

We were cleared for the approach for the ILS runway 4R when we reached the final approach fix dooin intersection we received an RA for an aircraft flying below us coming from our 11 o'clock it passed directly underneath us approximately 500 feet below. The captain and I spotted the aircraft and kept a close eye on it to determine if evasive action was needed. Once cleared I told ewr tower what had happened; they asked if we received an RA and I told them yes. No other action or ATC communication occurred and the flight ended normally. We had been told that a helicopter had us in sight approximately a minute or two earlier and they would maintain visual separation. I am unsure if it was the same aircraft.communication between air crews and ATC could have been clearer.

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Original NASA ASRS Text

Title: EMB-145 First Officer reported responding to a RA on approach to EWR Runway 4R from an aircraft that passed 500 feet below.

Narrative: We were cleared for the approach for the ILS runway 4R when we reached the final approach fix DOOIN intersection we received an RA for an aircraft flying below us coming from our 11 o'clock it passed directly underneath us approximately 500 feet below. The captain and I spotted the aircraft and kept a close eye on it to determine if evasive action was needed. Once cleared I told EWR tower what had happened; they asked if we received an RA and I told them yes. No other action or ATC communication occurred and the flight ended normally. We had been told that a helicopter had us in sight approximately a minute or two earlier and they would maintain visual separation. I am unsure if it was the same aircraft.Communication between air crews and ATC could have been clearer.

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.