Narrative:

Medium large transport X was departing abe en route to pit and came within 2.218 NM and 400' of medium large transport Y en route from lhy to ard, destination blm. The problem was discovered by the ny center computer and reported by a ny center floor manager. Action taken; medium large transport Y was instructed to maintain 10000' MSL and medium large transport X was instructed to maintain 9000' MSL. No evasive action was required. Factors contributing to the incident were the performance of medium large transport Y's transponder and the performance of abe's ASRS secondary and primary radar, rather the lack of performance. I believe the incident occurred due to the fact that medium large transport Y's primary target was non existent, perhaps due to his proximity and speed to the antenna, and that his tag acquired on another unknown beacon control slash separated from that of medium large transport X's position. It took a long time to take the handoff, from ny center sector 91 because medium large transport Y's tag was either in target update status or flashing ambiguity. When the tag did acquire the handoff was accomplished. Five mi later the tag of medium large transport Y dropped into non beacon status. At this time it was recognized that medium large transport X needed higher than 8000' MSL (abe vertical airspace limit) due to small transport Z, traffic 11 to 12 O'clock for 11 NM nwbound at 8000' on V164. Control for higher to 11000' MSL was obtained from ZNY 92. Medium large transport Y acquired the ARTS ii tag, on a beacon target 4 NM southwest of medium large transport X's projected flight path for at least two sweeps. I observed this and climbed medium large transport X to 11000'. Medium large transport Y was instructed to proceed direct ard and maintain 9000'. (I'd like to note that at this point the tapes were being changed and no further conversation with medium large transport X and medium large transport Y was recorded. The next transmission by me was to medium large transport Y several minutes later, after the incident occurred.) I then observed that medium large transport Y's tag 4 NM southwest of beacon control slash in medium large transport X's 1 to 2 O'clock position for 3 NM. I believed that might be medium large transport Y and instructed him to maintain 10000'. He acknowledged. Medium large transport X was instructed to maintain 9000 and I did not receive acknowledgement as there were seven aircraft on frequency. I believe I was stepped on and medium large transport X was also stepped on if he did reply, as there were several calls at once. Medium large transport X's ARTS tag superimposed with that of an en route small aircraft at 50 to avp. When the tags were moved medium large transport X indicated 8800 or so and I observed his climb through 9300. I queried him about 9000 and I received a negative response. Medium large transport Y reacquired 5 or 6 NM later and was handed off to the next controller, abe ds radar. The tag dropped again several times and did not retag until the ds controller asked him to try another transponder. Medium large transport X was transferred to ZNY 92, 135.75.

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Original NASA ASRS Text

Title: ACR MLG CLIMBED THROUGH ALT OF CPR MLG WITH FAULTY TRANSPONDER, RESULTING IN LESS THAN STANDARD SEPARATION.

Narrative: MLG X WAS DEPARTING ABE ENRTE TO PIT AND CAME WITHIN 2.218 NM AND 400' OF MLG Y ENRTE FROM LHY TO ARD, DEST BLM. THE PROB WAS DISCOVERED BY THE NY CTR COMPUTER AND RPTED BY A NY CTR FLOOR MGR. ACTION TAKEN; MLG Y WAS INSTRUCTED TO MAINTAIN 10000' MSL AND MLG X WAS INSTRUCTED TO MAINTAIN 9000' MSL. NO EVASIVE ACTION WAS REQUIRED. FACTORS CONTRIBUTING TO THE INCIDENT WERE THE PERFORMANCE OF MLG Y'S TRANSPONDER AND THE PERFORMANCE OF ABE'S ASRS SECONDARY AND PRIMARY RADAR, RATHER THE LACK OF PERFORMANCE. I BELIEVE THE INCIDENT OCCURRED DUE TO THE FACT THAT MLG Y'S PRIMARY TARGET WAS NON EXISTENT, PERHAPS DUE TO HIS PROX AND SPD TO THE ANTENNA, AND THAT HIS TAG ACQUIRED ON ANOTHER UNKNOWN BEACON CONTROL SLASH SEPARATED FROM THAT OF MLG X'S POS. IT TOOK A LONG TIME TO TAKE THE HANDOFF, FROM NY CTR SECTOR 91 BECAUSE MLG Y'S TAG WAS EITHER IN TARGET UPDATE STATUS OR FLASHING AMBIGUITY. WHEN THE TAG DID ACQUIRE THE HANDOFF WAS ACCOMPLISHED. FIVE MI LATER THE TAG OF MLG Y DROPPED INTO NON BEACON STATUS. AT THIS TIME IT WAS RECOGNIZED THAT MLG X NEEDED HIGHER THAN 8000' MSL (ABE VERTICAL AIRSPACE LIMIT) DUE TO SMT Z, TFC 11 TO 12 O'CLOCK FOR 11 NM NWBOUND AT 8000' ON V164. CONTROL FOR HIGHER TO 11000' MSL WAS OBTAINED FROM ZNY 92. MLG Y ACQUIRED THE ARTS II TAG, ON A BEACON TARGET 4 NM SW OF MLG X'S PROJECTED FLT PATH FOR AT LEAST TWO SWEEPS. I OBSERVED THIS AND CLBED MLG X TO 11000'. MLG Y WAS INSTRUCTED TO PROCEED DIRECT ARD AND MAINTAIN 9000'. (I'D LIKE TO NOTE THAT AT THIS POINT THE TAPES WERE BEING CHANGED AND NO FURTHER CONVERSATION WITH MLG X AND MLG Y WAS RECORDED. THE NEXT XMISSION BY ME WAS TO MLG Y SEVERAL MINUTES LATER, AFTER THE INCIDENT OCCURRED.) I THEN OBSERVED THAT MLG Y'S TAG 4 NM SW OF BEACON CONTROL SLASH IN MLG X'S 1 TO 2 O'CLOCK POS FOR 3 NM. I BELIEVED THAT MIGHT BE MLG Y AND INSTRUCTED HIM TO MAINTAIN 10000'. HE ACKNOWLEDGED. MLG X WAS INSTRUCTED TO MAINTAIN 9000 AND I DID NOT RECEIVE ACKNOWLEDGEMENT AS THERE WERE SEVEN ACFT ON FREQ. I BELIEVE I WAS STEPPED ON AND MLG X WAS ALSO STEPPED ON IF HE DID REPLY, AS THERE WERE SEVERAL CALLS AT ONCE. MLG X'S ARTS TAG SUPERIMPOSED WITH THAT OF AN ENRTE SMA AT 50 TO AVP. WHEN THE TAGS WERE MOVED MLG X INDICATED 8800 OR SO AND I OBSERVED HIS CLB THROUGH 9300. I QUERIED HIM ABOUT 9000 AND I RECEIVED A NEGATIVE RESPONSE. MLG Y REACQUIRED 5 OR 6 NM LATER AND WAS HANDED OFF TO THE NEXT CTLR, ABE DS RADAR. THE TAG DROPPED AGAIN SEVERAL TIMES AND DID NOT RETAG UNTIL THE DS CTLR ASKED HIM TO TRY ANOTHER TRANSPONDER. MLG X WAS TRANSFERRED TO ZNY 92, 135.75.

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.