Narrative:

Aircraft departed runway 4 at lga. Departure first gave a turn to 360 degrees, then right to 090 degrees. We were asked to expedite climb through 4000' and climb to 10000'. At approximately 3000' we were told to turn to 360 degrees (I think) again and that we had traffic inbound to lga at 4000' and 3 mi. First officer saw the traffic turning away from us at a distance of approximately 2 mi as we passed through 4000'. I think possibly the controller overestimated our rate of climb. This was a warm day and aircraft was heavy. The large turns after takeoff also served to slow our climb. I don't know if this was a near miss as I never saw the traffic. Sep may have been less than required.

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Original NASA ASRS Text

Title: LOSS OF LEGAL SEPARATION AND POSSIBLY A POTENTIAL CONFLICT OCCURRED DURING DEP RADAR VECTOR ROUTE.

Narrative: ACFT DEPARTED RWY 4 AT LGA. DEP FIRST GAVE A TURN TO 360 DEGS, THEN RIGHT TO 090 DEGS. WE WERE ASKED TO EXPEDITE CLB THROUGH 4000' AND CLB TO 10000'. AT APPROX 3000' WE WERE TOLD TO TURN TO 360 DEGS (I THINK) AGAIN AND THAT WE HAD TFC INBND TO LGA AT 4000' AND 3 MI. F/O SAW THE TFC TURNING AWAY FROM US AT A DISTANCE OF APPROX 2 MI AS WE PASSED THROUGH 4000'. I THINK POSSIBLY THE CTLR OVERESTIMATED OUR RATE OF CLB. THIS WAS A WARM DAY AND ACFT WAS HVY. THE LARGE TURNS AFTER TKOF ALSO SERVED TO SLOW OUR CLB. I DON'T KNOW IF THIS WAS A NEAR MISS AS I NEVER SAW THE TFC. SEP MAY HAVE BEEN LESS THAN REQUIRED.

Data retrieved from NASA's ASRS site as of August 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.