Narrative:

Northbound B737 FL370. Sbound F900 FL360. Radar controller descended FL370 to FL350. Not enough room. Human error.

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Original NASA ASRS Text

Title: ZBW RADAR ASSOC CTLR WITNESSED OPERROR AT FL360 WHEN CTLR FAILED TO ALLOW ENOUGH DISTANCE DURING OPPOSITE DIRECTION DESCENT OPS.

Narrative: NBOUND B737 FL370. SBOUND F900 FL360. RADAR CTLR DSNDED FL370 TO FL350. NOT ENOUGH ROOM. HUMAN ERROR.

Data retrieved from NASA's ASRS site as of May 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.