Narrative:

Shortly after takeoff, while complying with the newark 4 departure for runway 22R, we received a TCASII RA. I was attempting to locate the intruder aircraft which appeared to be at our 2-3 O'clock position and 200 ft vertically. The first officer, who was flying, immediately leveled off and began a descent. At that moment he looked to his right and saw a white ATR42 aircraft. This aircraft passed above and slightly behind our aircraft. We would estimate 200 ft vertically and horizontally. It was very close! I notified ATC (ewr tower on 118.3 MHZ) that we were complying with an RA. The tower operator acknowledged our transmission. He went on to say he did not issue a TA because he didn't want to upset us. The controller also said the crew of the ATR42 had us in sight and would maintain separation. I never heard that transmission. The controller was very insistent that I switch to departure at this point. I made a point to tell him again that we had passed very close to the other aircraft, then changed off to departure. The rest of the flight and landing in dtw was uneventful. Editorial: this is the second time in the past several months that I've had a near-miss with a commuter. I can only assume that these are pilots with no formation flying experience. They simply don't understand converging and diverging flight paths or rates of closure.

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Original NASA ASRS Text

Title: DURING SID DEP FROM EWR, FLC RECEIVED TCASII RA FROM ACFT ALSO DEPARTING EWR. FLC RPTED INTRUDER TO TWR WHO ACKNOWLEDGED AND SAID THEY DID NOT WANT TO ISSUE A TA SO AS NOT TO UPSET THE RPTR FLC, AND EVIDENTLY HAD BEEN IN COM WITH THE INTRUDER ACFT TO MAINTAIN VISUAL SEPARATION WITH RPTR. RPTR NEVER HEARD THOSE XMISSIONS.

Narrative: SHORTLY AFTER TKOF, WHILE COMPLYING WITH THE NEWARK 4 DEP FOR RWY 22R, WE RECEIVED A TCASII RA. I WAS ATTEMPTING TO LOCATE THE INTRUDER ACFT WHICH APPEARED TO BE AT OUR 2-3 O'CLOCK POS AND 200 FT VERTLY. THE FO, WHO WAS FLYING, IMMEDIATELY LEVELED OFF AND BEGAN A DSCNT. AT THAT MOMENT HE LOOKED TO HIS R AND SAW A WHITE ATR42 ACFT. THIS ACFT PASSED ABOVE AND SLIGHTLY BEHIND OUR ACFT. WE WOULD ESTIMATE 200 FT VERTLY AND HORIZLY. IT WAS VERY CLOSE! I NOTIFIED ATC (EWR TWR ON 118.3 MHZ) THAT WE WERE COMPLYING WITH AN RA. THE TWR OPERATOR ACKNOWLEDGED OUR XMISSION. HE WENT ON TO SAY HE DID NOT ISSUE A TA BECAUSE HE DIDN'T WANT TO UPSET US. THE CTLR ALSO SAID THE CREW OF THE ATR42 HAD US IN SIGHT AND WOULD MAINTAIN SEPARATION. I NEVER HEARD THAT XMISSION. THE CTLR WAS VERY INSISTENT THAT I SWITCH TO DEP AT THIS POINT. I MADE A POINT TO TELL HIM AGAIN THAT WE HAD PASSED VERY CLOSE TO THE OTHER ACFT, THEN CHANGED OFF TO DEP. THE REST OF THE FLT AND LNDG IN DTW WAS UNEVENTFUL. EDITORIAL: THIS IS THE SECOND TIME IN THE PAST SEVERAL MONTHS THAT I'VE HAD A NEAR-MISS WITH A COMMUTER. I CAN ONLY ASSUME THAT THESE ARE PLTS WITH NO FORMATION FLYING EXPERIENCE. THEY SIMPLY DON'T UNDERSTAND CONVERGING AND DIVERGING FLT PATHS OR RATES OF CLOSURE.

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.