B737 captain reported near midair collision responding to TCAS RA for overflying traffic.

Attributes
ACN	1551480
Time
Date	201806
Place
Locale Reference	N90.TRACON
State Reference	NY
Aircraft 1
Make Model Name	B737 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	Climb
Route In Use	Vectors
Flight Plan	IFR
Aircraft 2
Flight Phase	Cruise
Person 1
Function	Captain Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 235 Flight Crew Type 2404
Events
Anomaly	Conflict NMAC Deviation - Procedural Clearance
Miss Distance	Horizontal 0 Vertical 300

Narrative:

While flying as captain with autopilot on and complying with heading assigned 320 and climb to 16;000; [we] received TCAS traffic warning passing through 12;000 [feet]. [We] started to look for traffic at about 10 o'clock and quickly received TCAS RA leveloff. [We] complied; leveling off at 12;500 feet. Was unable to visually acquire traffic; but noted TCAS symbol showed they passed over us within 300 feet. Notified ATC; who issued [a] new heading; and commented the traffic was transitioning area without communications. Dispatch/[operations] [were] notified.

Original NASA ASRS Text

Title: B737 Captain reported NMAC responding to TCAS RA for overflying traffic.

Narrative: While flying as Captain with autopilot on and complying with heading assigned 320 and climb to 16;000; [we] received TCAS traffic warning passing through 12;000 [feet]. [We] started to look for traffic at about 10 o'clock and quickly received TCAS RA LEVELOFF. [We] complied; leveling off at 12;500 feet. Was unable to visually acquire traffic; but noted TCAS symbol showed they passed over us within 300 feet. Notified ATC; who issued [a] new heading; and commented the traffic was transitioning area without communications. Dispatch/[Operations] [were] notified.

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.