Narrative:

Departing runway 4L at newark, newark ii departure prior to reaching the clearance limit on the SID 2500' we were cleared to 4000'. Traffic was then issued at 2 O'clock 4500' and we were cleared to turn to 290 degree. I began the turn and looked right for the traffic. While doing so I flew through 4000'. The awi alerted me and I arrested the excursion at 4700'. I then immediately returned to 4000'. The controller reminded us of our assigned altitude and reported the traffic 10 O'clock at 4500' orbiting. For what it's worth: I believe the traffic at 2 O'clock orbiting at 4500' was issued passing through about 3600'. I also believe that traffic was issued in error and was actually the traffic at 10 O'clock orbiting at 4500'. I am led to believe this because traffic is not usually issued on the right with a turn to the left unless a conflict exists. I don't feel that was the case this time because the turn was to 290 degree as depicted on the SID. I didn't see traffic at 2 O'clock. We did see the traffic at 10 O'clock. I believe the 10 O'clock traffic was the reason for the 4000' restriction.

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Original NASA ASRS Text

Title: WDB FLT CREW CONTINUED CLIMB ABOVE ASSIGNED ALT. CREATED LESS THAN STANDARD SEPARATION WITH VFR TRAFFIC.

Narrative: DEPARTING RWY 4L AT NEWARK, NEWARK II DEP PRIOR TO REACHING THE CLRNC LIMIT ON THE SID 2500' WE WERE CLRED TO 4000'. TFC WAS THEN ISSUED AT 2 O'CLOCK 4500' AND WE WERE CLRED TO TURN TO 290 DEG. I BEGAN THE TURN AND LOOKED RIGHT FOR THE TFC. WHILE DOING SO I FLEW THROUGH 4000'. THE AWI ALERTED ME AND I ARRESTED THE EXCURSION AT 4700'. I THEN IMMEDIATELY RETURNED TO 4000'. THE CTLR REMINDED US OF OUR ASSIGNED ALT AND REPORTED THE TFC 10 O'CLOCK AT 4500' ORBITING. FOR WHAT IT'S WORTH: I BELIEVE THE TFC AT 2 O'CLOCK ORBITING AT 4500' WAS ISSUED PASSING THROUGH ABOUT 3600'. I ALSO BELIEVE THAT TFC WAS ISSUED IN ERROR AND WAS ACTUALLY THE TFC AT 10 O'CLOCK ORBITING AT 4500'. I AM LED TO BELIEVE THIS BECAUSE TFC IS NOT USUALLY ISSUED ON THE RIGHT WITH A TURN TO THE LEFT UNLESS A CONFLICT EXISTS. I DON'T FEEL THAT WAS THE CASE THIS TIME BECAUSE THE TURN WAS TO 290 DEG AS DEPICTED ON THE SID. I DIDN'T SEE TFC AT 2 O'CLOCK. WE DID SEE THE TFC AT 10 O'CLOCK. I BELIEVE THE 10 O'CLOCK TFC WAS THE REASON FOR THE 4000' RESTRICTION.

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.