Narrative:

Our aircraft was on departure from laguardia in a climb to 5000' MSL, passing 4000' we were told by departure control to turn to 180 degree. After starting a left turn (shortest direction) to 180, controller advised us to make it a hard right turn and that we had traffic at 2 O'clock. First officer spotted the traffic and advised the PF to stop climbing. This occurred at 4500' MSL. The traffic which had reported seeing us took no evasive action and flew directly over us. Approximately sep was 500'. The controller seemed to be task saturated and mistakenly called for a hard right turn west/O noticing an altitude conflict. Had we not seen the traffic or had we been in IMC and followed the controller's directions, the result could have been tragic.

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Original NASA ASRS Text

Title: LGT IN CLIMB DEPARTING LGA INSTRUCTED TO TURN TO 180 STARTED LEFT TURN BUT CTLR SAID TURN RIGHT. FO SPOTTED THE TRAFFIC AND ADVISED CAPT TO STOP CLIMB. TRAFFIC PASSED OVER AT APPROX 500' ADVISING THEY HAD LGT IN SIGHT.

Narrative: OUR ACFT WAS ON DEP FROM LAGUARDIA IN A CLB TO 5000' MSL, PASSING 4000' WE WERE TOLD BY DEP CTL TO TURN TO 180 DEG. AFTER STARTING A L TURN (SHORTEST DIRECTION) TO 180, CTLR ADVISED US TO MAKE IT A HARD R TURN AND THAT WE HAD TFC AT 2 O'CLOCK. F/O SPOTTED THE TFC AND ADVISED THE PF TO STOP CLBING. THIS OCCURRED AT 4500' MSL. THE TFC WHICH HAD RPTED SEEING US TOOK NO EVASIVE ACTION AND FLEW DIRECTLY OVER US. APPROX SEP WAS 500'. THE CTLR SEEMED TO BE TASK SATURATED AND MISTAKENLY CALLED FOR A HARD R TURN W/O NOTICING AN ALT CONFLICT. HAD WE NOT SEEN THE TFC OR HAD WE BEEN IN IMC AND FOLLOWED THE CTLR'S DIRECTIONS, THE RESULT COULD HAVE BEEN TRAGIC.

Data retrieved from NASA's ASRS site as of July 2007 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.