Narrative:

A loss of standard IFR (minimum) separation occurred between small aircraft X and small aircraft Y on oct/tue/96 at approximately XB35 pm. I am the radar controller who is being labeled as the 'primary' cause for the loss of separation. At the time of the error, I had just returned from a position break, and was working at a different sector when I was notified of the error. I was not talking to either aircraft, nor was I assigned to the sector in which the error occurred. I would like to describe what happened, what events led up to this error. At XA50 pm, the williamsport tower called for 2 IFR clrncs. At this time, I was the radar controller in charge of sector 93, area D, in ny ARTCC. I was the IFR controling sector for issuing clrncs and providing separation for the ipt airport. I issued the first clearance and both the tower controller and I were interrupted during the issuance of the second clearance, and when I issued the transponder code part of the second IFR clearance, I issued the same code as in the first clearance. Basically, the same transponder code was issued to 2 different flts and neither I nor the tower controller realized it. The second flight (the one who got the wrong code) was small aircraft X. Small aircraft X reported airborne out of 1500 ft MSL. We normally will not receive a radar return until the departures are above 4000 ft MSL. I acknowledge his transmission, and issued him an altitude assignment of 5000 ft. Small aircraft X is a PA34 climbing slow and moving slow. After about 2 mins, I gave a position relief briefing to another controller who was letting me go out to a break. When I got to the 'traffic' part of the briefing, I didn't reference the non radar departure (small aircraft X was never informed of radar contact). Before I was relieved from the sector, I did enter the appropriate departure message into the computer, and the flight progress strip was marked accurately and correctly and was in the active portion of the strip bay. After I took a break and was working another sector, I was notified of an error which took place in ZOB's airspace. The next sector adjacent of the one in which small aircraft X was flying through. Evidently what had happened was, I never knew that I didn't mention the non radar traffic to the new controller until after I heard the tape. The new controller never questioned the active strip in the bay, nor did he ever question the limited data block (transponder code altitude) on small aircraft X in his sector. Because small aircraft X was on the wrong transponder code, a full data block was never automatically acquired, thus providing automated means of radar identify. During the time (and it was about 30 mins) small aircraft X was in his (the new controller) sector of responsibility, small aircraft X never transmitted to the controller, and the new controller was not aware he was there. Also, during this time, the new controller received a call from another aircraft requesting VFR flight following. The new controller didn't have a blank flight progress strip to write on, so he wrote on the bottom strip in the active bay, which was small aircraft X strip. The ZOB controller became aware of the incident when small aircraft X reported on their frequency saying he lost radio contact with ny ARTCC and he advised them (ZOB) that he noticed an aircraft (small aircraft Y) going the other way at his altitude. How can an error like this be avoided in the future? We could certainly use some more people working in our facility in our operation. I have been here 11 yrs, and I would say morale is the lowest I have ever seen. You are constantly working with skeleton crews, fatigue is a problem.

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Original NASA ASRS Text

Title: ARTCC RADAR CTLR ISSUED SAME XPONDER CODE TO 2 ACFT DEPARTING FROM IPT. TWR CTLR DID NOT CATCH MISTAKE. PA34 WITH WRONG CODE TOOK OFF, CLBED TO 5000 FT AND NEVER RADAR IDENTED. CTLR WHO ISSUED CLRNC WAS RELIEVED FOR BREAK AND FORGOT TO INCLUDE PA34 IN BRIEFING. RELIEVING CTLR DID NOT SEE LIMITED DATA BLOCK ON PA34 AND DID NOT HDOF TO ADJACENT ARTCC. PA34 PLT MADE FREQ CHANGE TO NEXT ARTCC WITHOUT CLRNC AND QUESTIONED NEW CTLR ON OPPOSITE DIRECTION TFC AT SAME ALT. SYS ERROR HAD OCCURRED.

Narrative: A LOSS OF STANDARD IFR (MINIMUM) SEPARATION OCCURRED BTWN SMA X AND SMA Y ON OCT/TUE/96 AT APPROX XB35 PM. I AM THE RADAR CTLR WHO IS BEING LABELED AS THE 'PRIMARY' CAUSE FOR THE LOSS OF SEPARATION. AT THE TIME OF THE ERROR, I HAD JUST RETURNED FROM A POS BREAK, AND WAS WORKING AT A DIFFERENT SECTOR WHEN I WAS NOTIFIED OF THE ERROR. I WAS NOT TALKING TO EITHER ACFT, NOR WAS I ASSIGNED TO THE SECTOR IN WHICH THE ERROR OCCURRED. I WOULD LIKE TO DESCRIBE WHAT HAPPENED, WHAT EVENTS LED UP TO THIS ERROR. AT XA50 PM, THE WILLIAMSPORT TWR CALLED FOR 2 IFR CLRNCS. AT THIS TIME, I WAS THE RADAR CTLR IN CHARGE OF SECTOR 93, AREA D, IN NY ARTCC. I WAS THE IFR CTLING SECTOR FOR ISSUING CLRNCS AND PROVIDING SEPARATION FOR THE IPT ARPT. I ISSUED THE FIRST CLRNC AND BOTH THE TWR CTLR AND I WERE INTERRUPTED DURING THE ISSUANCE OF THE SECOND CLRNC, AND WHEN I ISSUED THE XPONDER CODE PART OF THE SECOND IFR CLRNC, I ISSUED THE SAME CODE AS IN THE FIRST CLRNC. BASICALLY, THE SAME XPONDER CODE WAS ISSUED TO 2 DIFFERENT FLTS AND NEITHER I NOR THE TWR CTLR REALIZED IT. THE SECOND FLT (THE ONE WHO GOT THE WRONG CODE) WAS SMA X. SMA X RPTED AIRBORNE OUT OF 1500 FT MSL. WE NORMALLY WILL NOT RECEIVE A RADAR RETURN UNTIL THE DEPS ARE ABOVE 4000 FT MSL. I ACKNOWLEDGE HIS XMISSION, AND ISSUED HIM AN ALT ASSIGNMENT OF 5000 FT. SMA X IS A PA34 CLBING SLOW AND MOVING SLOW. AFTER ABOUT 2 MINS, I GAVE A POS RELIEF BRIEFING TO ANOTHER CTLR WHO WAS LETTING ME GO OUT TO A BREAK. WHEN I GOT TO THE 'TFC' PART OF THE BRIEFING, I DIDN'T REF THE NON RADAR DEP (SMA X WAS NEVER INFORMED OF RADAR CONTACT). BEFORE I WAS RELIEVED FROM THE SECTOR, I DID ENTER THE APPROPRIATE DEP MESSAGE INTO THE COMPUTER, AND THE FLT PROGRESS STRIP WAS MARKED ACCURATELY AND CORRECTLY AND WAS IN THE ACTIVE PORTION OF THE STRIP BAY. AFTER I TOOK A BREAK AND WAS WORKING ANOTHER SECTOR, I WAS NOTIFIED OF AN ERROR WHICH TOOK PLACE IN ZOB'S AIRSPACE. THE NEXT SECTOR ADJACENT OF THE ONE IN WHICH SMA X WAS FLYING THROUGH. EVIDENTLY WHAT HAD HAPPENED WAS, I NEVER KNEW THAT I DIDN'T MENTION THE NON RADAR TFC TO THE NEW CTLR UNTIL AFTER I HEARD THE TAPE. THE NEW CTLR NEVER QUESTIONED THE ACTIVE STRIP IN THE BAY, NOR DID HE EVER QUESTION THE LIMITED DATA BLOCK (XPONDER CODE ALT) ON SMA X IN HIS SECTOR. BECAUSE SMA X WAS ON THE WRONG XPONDER CODE, A FULL DATA BLOCK WAS NEVER AUTOMATICALLY ACQUIRED, THUS PROVIDING AUTOMATED MEANS OF RADAR IDENT. DURING THE TIME (AND IT WAS ABOUT 30 MINS) SMA X WAS IN HIS (THE NEW CTLR) SECTOR OF RESPONSIBILITY, SMA X NEVER XMITTED TO THE CTLR, AND THE NEW CTLR WAS NOT AWARE HE WAS THERE. ALSO, DURING THIS TIME, THE NEW CTLR RECEIVED A CALL FROM ANOTHER ACFT REQUESTING VFR FLT FOLLOWING. THE NEW CTLR DIDN'T HAVE A BLANK FLT PROGRESS STRIP TO WRITE ON, SO HE WROTE ON THE BOTTOM STRIP IN THE ACTIVE BAY, WHICH WAS SMA X STRIP. THE ZOB CTLR BECAME AWARE OF THE INCIDENT WHEN SMA X RPTED ON THEIR FREQ SAYING HE LOST RADIO CONTACT WITH NY ARTCC AND HE ADVISED THEM (ZOB) THAT HE NOTICED AN ACFT (SMA Y) GOING THE OTHER WAY AT HIS ALT. HOW CAN AN ERROR LIKE THIS BE AVOIDED IN THE FUTURE? WE COULD CERTAINLY USE SOME MORE PEOPLE WORKING IN OUR FACILITY IN OUR OP. I HAVE BEEN HERE 11 YRS, AND I WOULD SAY MORALE IS THE LOWEST I HAVE EVER SEEN. YOU ARE CONSTANTLY WORKING WITH SKELETON CREWS, FATIGUE IS A PROB.

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.