Narrative:

2 aircraft opposite direction on same airway. Aircraft did not make assigned frequency change. Both controllers thought other controller had both aircraft. At about 7 mi distance, attempt was made to turn and climb 1 aircraft, and descend the other. Pilots were both slow to answer. 1 aircraft turned and climbed quickly providing a divergence off course. It would have been better had we never allowed them at the same altitude to begin with, but it is typical in a dense environment like this. The pilots did not help in their slow response time and frequency changes were a factor.

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Original NASA ASRS Text

Title: N90 CTLR LOST SEPARATION WITH 2 OPPOSITE DIRECTION ENRTE ACFT ON SAME AIRWAY.

Narrative: 2 ACFT OPPOSITE DIRECTION ON SAME AIRWAY. ACFT DID NOT MAKE ASSIGNED FREQ CHANGE. BOTH CTLRS THOUGHT OTHER CTLR HAD BOTH ACFT. AT ABOUT 7 MI DISTANCE, ATTEMPT WAS MADE TO TURN AND CLB 1 ACFT, AND DSND THE OTHER. PLTS WERE BOTH SLOW TO ANSWER. 1 ACFT TURNED AND CLBED QUICKLY PROVIDING A DIVERGENCE OFF COURSE. IT WOULD HAVE BEEN BETTER HAD WE NEVER ALLOWED THEM AT THE SAME ALT TO BEGIN WITH, BUT IT IS TYPICAL IN A DENSE ENVIRONMENT LIKE THIS. THE PLTS DID NOT HELP IN THEIR SLOW RESPONSE TIME AND FREQ CHANGES WERE A FACTOR.

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.