Narrative:

Air carrier X MD88 off cvg at 330, requesting 370. The aircraft was level for several mins before the previous controller put X on my frequency. I judged by how quickly the X got to 330 and by the pilot's estimate of how long it would take to reach FL370 that there would be plenty of time to clear FL350 air carrier Y. The clber was sebound, and the FL350 Y was swbound. I cleared X to FL370, and went on to other things, though I put a polygon up on the clber to remind myself to communication back to it. By the time I got back to it (I was busy), it was clear that the rate of climb was too slow. Also, X had a slight left turn in his flight plan at hvq, and I thought he would be going straight. When X made the turn, he became a conflict with the 350 aircraft. I turned both 15 degrees right and then to harder headings. The 2 turns to the clber added up; to about 55 degrees and to the FL350, about 45 degrees. It was a little too late and I asked X to verify level at 370. X said he was out of 367, as I was asking again, aedp activated and I lost separation. His report came about 10 seconds too late.

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Original NASA ASRS Text

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

Narrative: ACR X MD88 OFF CVG AT 330, REQUESTING 370. THE ACFT WAS LEVEL FOR SEVERAL MINS BEFORE THE PREVIOUS CTLR PUT X ON MY FREQ. I JUDGED BY HOW QUICKLY THE X GOT TO 330 AND BY THE PLT'S ESTIMATE OF HOW LONG IT WOULD TAKE TO REACH FL370 THAT THERE WOULD BE PLENTY OF TIME TO CLR FL350 ACR Y. THE CLBER WAS SEBOUND, AND THE FL350 Y WAS SWBOUND. I CLRED X TO FL370, AND WENT ON TO OTHER THINGS, THOUGH I PUT A POLYGON UP ON THE CLBER TO REMIND MYSELF TO COM BACK TO IT. BY THE TIME I GOT BACK TO IT (I WAS BUSY), IT WAS CLR THAT THE RATE OF CLB WAS TOO SLOW. ALSO, X HAD A SLIGHT L TURN IN HIS FLT PLAN AT HVQ, AND I THOUGHT HE WOULD BE GOING STRAIGHT. WHEN X MADE THE TURN, HE BECAME A CONFLICT WITH THE 350 ACFT. I TURNED BOTH 15 DEGS R AND THEN TO HARDER HDGS. THE 2 TURNS TO THE CLBER ADDED UP; TO ABOUT 55 DEGS AND TO THE FL350, ABOUT 45 DEGS. IT WAS A LITTLE TOO LATE AND I ASKED X TO VERIFY LEVEL AT 370. X SAID HE WAS OUT OF 367, AS I WAS ASKING AGAIN, AEDP ACTIVATED AND I LOST SEPARATION. HIS RPT CAME ABOUT 10 SECONDS TOO LATE.

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.