Narrative:

Level at 4;000 ft; and we got a TCAS RA. We advised ATC and he apologized for not informing us of traffic. A/C passed 400 ft above us. They were supposed to be level at 4;500 ft.

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Original NASA ASRS Text

Title: ERJ-190 Captain reported an NMAC with another aircraft in the vicinity of LGA.

Narrative: Level at 4;000 ft; and we got a TCAS RA. We advised ATC and he apologized for not informing us of traffic. A/C passed 400 ft above us. They were supposed to be level at 4;500 ft.

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.