Narrative:

I was working at sector 18 with a moderate traffic load, the 'D' side was staffed. Cpr X (elgo) departed oqu and after receiving the aircraft from pvd approach I climbed the aircraft to FL390. Several aircraft were checking on or being changed to other frequencys during this time. Sector 31 controller called me and requested that I stop X at FL280 for traffic. I said I would. The other controller then requested approval to stop military X (F-15) at FL290 I approved this and he disconnected. I thought that I then amended X climb to FL280 and changed him to sector 31's frequency. Another aircraft checked on departing bos and I climbed him. A few moments later the sector 31 controller requested communications with X. I told him that I would try him again. I issued the frequency change and responded. Listening to the tape of the incident, I didn't hear myself give the amended altitude to X. When the pilot checked on sector 31's frequency he was still climbing to FL390. The controller told him to maintain FL280 and called his traffic at 2 mi and at FL290. The F-15 said that X was within 300 ft before they were clear. I feel the problem occurred when I let myself get distraction by other traffic in my airspace and I didn't issue the amended altitude to X.

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Original NASA ASRS Text

Title: CPR X CLB THROUGH OCCUPIED ALT HAD LTSS FROM MIL Y. SYS ERROR.

Narrative: I WAS WORKING AT SECTOR 18 WITH A MODERATE TFC LOAD, THE 'D' SIDE WAS STAFFED. CPR X (ELGO) DEPARTED OQU AND AFTER RECEIVING THE ACFT FROM PVD APCH I CLBED THE ACFT TO FL390. SEVERAL ACFT WERE CHKING ON OR BEING CHANGED TO OTHER FREQS DURING THIS TIME. SECTOR 31 CTLR CALLED ME AND REQUESTED THAT I STOP X AT FL280 FOR TFC. I SAID I WOULD. THE OTHER CTLR THEN REQUESTED APPROVAL TO STOP MIL X (F-15) AT FL290 I APPROVED THIS AND HE DISCONNECTED. I THOUGHT THAT I THEN AMENDED X CLB TO FL280 AND CHANGED HIM TO SECTOR 31'S FREQ. ANOTHER ACFT CHKED ON DEPARTING BOS AND I CLBED HIM. A FEW MOMENTS LATER THE SECTOR 31 CTLR REQUESTED COMS WITH X. I TOLD HIM THAT I WOULD TRY HIM AGAIN. I ISSUED THE FREQ CHANGE AND RESPONDED. LISTENING TO THE TAPE OF THE INCIDENT, I DIDN'T HEAR MYSELF GIVE THE AMENDED ALT TO X. WHEN THE PLT CHKED ON SECTOR 31'S FREQ HE WAS STILL CLBING TO FL390. THE CTLR TOLD HIM TO MAINTAIN FL280 AND CALLED HIS TFC AT 2 MI AND AT FL290. THE F-15 SAID THAT X WAS WITHIN 300 FT BEFORE THEY WERE CLR. I FEEL THE PROB OCCURRED WHEN I LET MYSELF GET DISTR BY OTHER TFC IN MY AIRSPACE AND I DIDN'T ISSUE THE AMENDED ALT TO X.

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.