Narrative:

At 5000 MSL feet; approximately 10 miles west of sli VOR; socal approach assigned us a left turn to a heading of 050 degrees. The captain initiated the turn with the autopilot engaged. Approximately 15-20 degrees into the left turn; socal approach quickly cleared us back to our original heading. As the aircraft was in the right turn back to approximately 070 degrees; we received a resolution advisory (RA) directing a climb; as it appeared that an aircraft was in close proximity to us at approximately 500' below our assigned altitude. The captain immediately followed the RA direction and began to climb; and I promptly notified socal approach that we were responding to a RA. At approximately 5500 MSL feet; the RA indicated a level off. A few seconds later; we received a subsequent RA directing another climb; however; it now it appeared that the aircraft was 300' directly beneath us. At approximately 5700' MSL; the RA indicated that we were clear of the conflict. The captain returned to the previously assigned altitude of 5000' MSL and I notified socal approach accordingly. Socal approach never made any mention of any traffic or the RA event. Also; we never saw the offending traffic during the RA event. We continued and landed uneventfully.

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Original NASA ASRS Text

Title: An air carrier pilot reported a TCAS RA CLIMB during a near miss with an unidentified aircraft at about 5;500 feet near SLI .

Narrative: At 5000 MSL feet; approximately 10 miles west of SLI VOR; SoCal Approach assigned us a left turn to a heading of 050 degrees. The Captain initiated the turn with the autopilot engaged. Approximately 15-20 degrees into the left turn; SoCal Approach quickly cleared us back to our original heading. As the aircraft was in the right turn back to approximately 070 degrees; we received a resolution advisory (RA) directing a climb; as it appeared that an aircraft was in close proximity to us at approximately 500' below our assigned altitude. The captain immediately followed the RA direction and began to climb; and I promptly notified SoCal Approach that we were responding to a RA. At approximately 5500 MSL feet; the RA indicated a level off. A few seconds later; we received a subsequent RA directing another climb; however; it now it appeared that the aircraft was 300' directly beneath us. At approximately 5700' MSL; the RA indicated that we were clear of the conflict. The captain returned to the previously assigned altitude of 5000' MSL and I notified SoCal Approach accordingly. SoCal approach never made any mention of any traffic or the RA event. Also; we never saw the offending traffic during the RA event. We continued and landed uneventfully.

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.