Narrative:

We were cleared out of the class D and to remain clear of class B. Departed runway 6 at teb VFR for a positioning flight; on heading 055 (teb advised of traffic converging from the north at our altitude;10 o'clock. Class B is 1;800 over teb lowering to 1;500 MSL we were at 1;300 MSL. TCAS gave traffic warning and teb advised of traffic 1 NM. Both crew members were looking for traffic but did not see it in the haze. TCAS showed the target at our altitude. I caught motion out of my peripheral vision slightly below us. I climbed while trying to get better fix on the traffic. Traffic passed under us approximately 200 to 250 feet. Captain; pilot not flying; advised me to watch altitude and I descended as the traffic passed clear. The floor of the class B transitions from 1;800 to 1;500 in the vicinity of where this occurred. My altitude may have exceeded 1;500 by 20 to 40 feet but I was not certain if we were actually at the 1;500 floor as this took place in less than a minute. We descended to 1;300 and continued out of the class D and contacted new york approach. Neither teb nor new york ATC mentioned an altitude violation. Had teb turned the traffic to the west; we would have not to make the abrupt altitude change. Had the other pilot turned on a landing light; it may have been easier to identify it in the ground clutter and haze. This is a crowded bit of airspace and is always a high workload time.

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Original NASA ASRS Text

Title: An air taxi pilot reported a near miss below NYC Class B airspace with an aircraft seen on TCAS and reported by ATC but difficult to visually identify because of the haze until it was within 1 mile.

Narrative: We were cleared out of the Class D and to remain clear of Class B. Departed Runway 6 at TEB VFR for a positioning flight; on heading 055 (TEB advised of traffic converging from the north at our altitude;10 o'clock. Class B is 1;800 over TEB lowering to 1;500 MSL we were at 1;300 MSL. TCAS gave traffic warning and TEB advised of traffic 1 NM. Both crew members were looking for traffic but did not see it in the haze. TCAS showed the target at our altitude. I caught motion out of my peripheral vision slightly below us. I climbed while trying to get better fix on the traffic. Traffic passed under us approximately 200 to 250 feet. Captain; pilot not flying; advised me to watch altitude and I descended as the traffic passed clear. The floor of the Class B transitions from 1;800 to 1;500 in the vicinity of where this occurred. My altitude may have exceeded 1;500 by 20 to 40 feet but I was not certain if we were actually at the 1;500 floor as this took place in less than a minute. We descended to 1;300 and continued out of the Class D and contacted New York Approach. Neither TEB nor New York ATC mentioned an altitude violation. Had TEB turned the traffic to the west; we would have not to make the abrupt altitude change. Had the other pilot turned on a landing light; it may have been easier to identify it in the ground clutter and haze. This is a crowded bit of airspace and is always a high workload time.

Data retrieved from NASA's ASRS site as of April 2012 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.