Narrative:

Dropped data block on air carrier Y heading south when I saw altitude 119 figured descending; assigned air carrier X 120 and saw aircraft converging. Stopped descent on air carrier X reported level 120; reported have aircraft in sight; pilot got RA and descended. Recommendation; not to drop data block until aircraft is finished leaving altitude.

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Original NASA ASRS Text

Title: ZNY Controller experienced a loss of separation event when descending traffic through an occupied altitude; the reporter listing a premature dropped data block as a causal factor.

Narrative: Dropped Data Block on Air Carrier Y heading south when I saw altitude 119 figured descending; assigned Air Carrier X 120 and saw aircraft converging. Stopped descent on Air Carrier X reported level 120; reported have aircraft in sight; pilot got RA and descended. Recommendation; not to drop Data Block until aircraft is finished leaving altitude.

Data retrieved from NASA's ASRS site as of April 2012 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.