Narrative:

I was PF on an empty repositioning leg to teb. We were being vectored for the ILS to runway 6 in good VMC. Level at 3000 ft MSL; passing by mmu; we saw a target appear on the TCAS at our 11 O'clock position; passing left to right; indicating 2800 ft MSL. We made visual contact with the traffic almost immediately. ATC had not yet advised us of the traffic; but we both realized it was going to be a conflict and simultaneously received an RA telling us to climb. I immediately disengaged the autoplt and responded to the RA. As I was doing so; ATC was advising us of the traffic. The PNF replied; telling the controller that we were responding to a TCAS RA and had climbed. The traffic passed almost directly underneath us. We climbed to approximately 3600 ft MSL before the TCAS advised that we were clear of conflict. At that time; I descended back down to our assigned altitude of 3000 ft MSL. The PNF advised ATC that we had returned to 3000 ft. The controller then asked us to say altitude; to which the PNF again replied 'level at 3000 ft.' ATC then said something along the lines of; 'well; I only show you at 2800 ft.' that was not the case. We checked all 3 altimeters against each other and against the current setting given to us and we were indicating 3000 ft exactly. Also; at no time during the rotation; or during the subsequent 4+ hours of flying in that aircraft from then until now; did ATC advise us that we might be indicating low. Given that and the fact that the floor of the class B in that area is 3000 ft MSL; we both thought this exchange with the controller was a little odd. It was almost as if he was blaming us for his mistake. Hopefully; we just misunderstood. I have rarely; if ever; worked with a new york approach controller that wasn't top notch.

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Original NASA ASRS Text

Title: A LR60 PILOT REPORTED A NMAC ON ARRIVAL TO TEB.

Narrative: I WAS PF ON AN EMPTY REPOSITIONING LEG TO TEB. WE WERE BEING VECTORED FOR THE ILS TO RWY 6 IN GOOD VMC. LEVEL AT 3000 FT MSL; PASSING BY MMU; WE SAW A TARGET APPEAR ON THE TCAS AT OUR 11 O'CLOCK POS; PASSING L TO R; INDICATING 2800 FT MSL. WE MADE VISUAL CONTACT WITH THE TFC ALMOST IMMEDIATELY. ATC HAD NOT YET ADVISED US OF THE TFC; BUT WE BOTH REALIZED IT WAS GOING TO BE A CONFLICT AND SIMULTANEOUSLY RECEIVED AN RA TELLING US TO CLB. I IMMEDIATELY DISENGAGED THE AUTOPLT AND RESPONDED TO THE RA. AS I WAS DOING SO; ATC WAS ADVISING US OF THE TFC. THE PNF REPLIED; TELLING THE CTLR THAT WE WERE RESPONDING TO A TCAS RA AND HAD CLBED. THE TFC PASSED ALMOST DIRECTLY UNDERNEATH US. WE CLBED TO APPROX 3600 FT MSL BEFORE THE TCAS ADVISED THAT WE WERE CLR OF CONFLICT. AT THAT TIME; I DSNDED BACK DOWN TO OUR ASSIGNED ALT OF 3000 FT MSL. THE PNF ADVISED ATC THAT WE HAD RETURNED TO 3000 FT. THE CTLR THEN ASKED US TO SAY ALT; TO WHICH THE PNF AGAIN REPLIED 'LEVEL AT 3000 FT.' ATC THEN SAID SOMETHING ALONG THE LINES OF; 'WELL; I ONLY SHOW YOU AT 2800 FT.' THAT WAS NOT THE CASE. WE CHKED ALL 3 ALTIMETERS AGAINST EACH OTHER AND AGAINST THE CURRENT SETTING GIVEN TO US AND WE WERE INDICATING 3000 FT EXACTLY. ALSO; AT NO TIME DURING THE ROTATION; OR DURING THE SUBSEQUENT 4+ HRS OF FLYING IN THAT ACFT FROM THEN UNTIL NOW; DID ATC ADVISE US THAT WE MIGHT BE INDICATING LOW. GIVEN THAT AND THE FACT THAT THE FLOOR OF THE CLASS B IN THAT AREA IS 3000 FT MSL; WE BOTH THOUGHT THIS EXCHANGE WITH THE CTLR WAS A LITTLE ODD. IT WAS ALMOST AS IF HE WAS BLAMING US FOR HIS MISTAKE. HOPEFULLY; WE JUST MISUNDERSTOOD. I HAVE RARELY; IF EVER; WORKED WITH A NEW YORK APCH CTLR THAT WASN'T TOP NOTCH.

Data retrieved from NASA's ASRS site as of May 2009 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.