Narrative:

As controller, I was working air carrier X eastbound on J82 overflying alb at FL210. Air carrier Y checked on to my frequency climbing to 17000' with a request altitude of 12190'. I observed air carrier X just east of air carrier Y and saw that air carrier X was level at FL210, and issued (I thought) FL190 to air carrier Y. Apparently, I issued FL210 to air carrier Y. He read back what I issued, and continued his climb. Both aircraft were given a frequency change, and air carrier Y checked in to the next sector climbing to FL210. Although FL190 was assigned in his data block, the next controller did not hear the discrepancy in the altitudes. The conflict alert went off as air carrier Y was climbing through 19500', and corrective action was taken. Supplemental information from acn 154632. Air carrier syr isp, while climbing to cruise altitude aircraft was issued clearance to climb to FL210 and handed off shortly thereafter to next controller. First officer contacted next controller while aircraft was climbing through FL200. Controller questioned our assigned altitude stating it should have been FL190. Aircraft was directed to turn immediately 60 degrees left and descended to FL190 west/O delay. No immediate aircraft conflict was stated by the controller and assurance of no problem was issued. The first controller may have issued the wrong altitude. As PIC I did not note FL210 as unusual since it is the filed altitude for syr-bdl which follows a near identical routing. The filed altitude for syr-isp however, was in fact FL190. The latter route I have flown much less often.

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Original NASA ASRS Text

Title: ACR X HAD LESS THAN STANDARD SEPARATION FROM ACR Y. SYSTEM ERROR.

Narrative: AS CTLR, I WAS WORKING ACR X EBND ON J82 OVERFLYING ALB AT FL210. ACR Y CHKED ON TO MY FREQ CLBING TO 17000' WITH A REQUEST ALT OF 12190'. I OBSERVED ACR X JUST E OF ACR Y AND SAW THAT ACR X WAS LEVEL AT FL210, AND ISSUED (I THOUGHT) FL190 TO ACR Y. APPARENTLY, I ISSUED FL210 TO ACR Y. HE READ BACK WHAT I ISSUED, AND CONTINUED HIS CLB. BOTH ACFT WERE GIVEN A FREQ CHANGE, AND ACR Y CHKED IN TO THE NEXT SECTOR CLBING TO FL210. ALTHOUGH FL190 WAS ASSIGNED IN HIS DATA BLOCK, THE NEXT CTLR DID NOT HEAR THE DISCREPANCY IN THE ALTS. THE CONFLICT ALERT WENT OFF AS ACR Y WAS CLBING THROUGH 19500', AND CORRECTIVE ACTION WAS TAKEN. SUPPLEMENTAL INFO FROM ACN 154632. ACR SYR ISP, WHILE CLBING TO CRUISE ALT ACFT WAS ISSUED CLRNC TO CLB TO FL210 AND HANDED OFF SHORTLY THEREAFTER TO NEXT CTLR. F/O CONTACTED NEXT CTLR WHILE ACFT WAS CLBING THROUGH FL200. CTLR QUESTIONED OUR ASSIGNED ALT STATING IT SHOULD HAVE BEEN FL190. ACFT WAS DIRECTED TO TURN IMMEDIATELY 60 DEGS L AND DSNDED TO FL190 W/O DELAY. NO IMMEDIATE ACFT CONFLICT WAS STATED BY THE CTLR AND ASSURANCE OF NO PROB WAS ISSUED. THE FIRST CTLR MAY HAVE ISSUED THE WRONG ALT. AS PIC I DID NOT NOTE FL210 AS UNUSUAL SINCE IT IS THE FILED ALT FOR SYR-BDL WHICH FOLLOWS A NEAR IDENTICAL RTING. THE FILED ALT FOR SYR-ISP HOWEVER, WAS IN FACT FL190. THE LATTER RTE I HAVE FLOWN MUCH LESS OFTEN.

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.