Narrative:

I was monitoring the speed of the aircraft as they climbed to 15000 ft and leveled. I noticed the second aircraft's speed increase and I tried to slow him down. I also descended the first aircraft and tried to use visual separation. Just not in time to maintain 5 mi.

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Original NASA ASRS Text

Title: ZBW CTLR EXPERIENCED OPERROR AT 15000 FT WHEN ACTIONS TAKEN TO RESOLVE AN OVERTAKE SIT WERE TOO LATE TO BE EFFECTIVE.

Narrative: I WAS MONITORING THE SPD OF THE ACFT AS THEY CLBED TO 15000 FT AND LEVELED. I NOTICED THE SECOND ACFT'S SPD INCREASE AND I TRIED TO SLOW HIM DOWN. I ALSO DSNDED THE FIRST ACFT AND TRIED TO USE VISUAL SEPARATION. JUST NOT IN TIME TO MAINTAIN 5 MI.

Data retrieved from NASA's ASRS site as of January 2009 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.