Narrative:

While climbing through 27000' medium large transport Y was spotted close aboard our right side. Mlt Y passed slightly below and aft of our aircraft. It appeared to be in a left turn and might have been attempting to evade us. When queried about the conflict ZJX replied that aircraft was under ZDC control and that they did not have a data block on him with his altitude. They later informed us that he was at approximately 26000' and climbing as he passed under and slightly aft of us. A contributing factor to this was having 2 aircraft in the same airspace being controled by separate centers.

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Original NASA ASRS Text

Title: ACR SAW WDB MLT IN CLOSE PROX. ZJX WORKING ACR WHILE MLT UNDER CONTROL OF ZDC. OPERATIONAL DEVIATION.

Narrative: WHILE CLBING THROUGH 27000' MLG Y WAS SPOTTED CLOSE ABOARD OUR RIGHT SIDE. MLT Y PASSED SLIGHTLY BELOW AND AFT OF OUR ACFT. IT APPEARED TO BE IN A LEFT TURN AND MIGHT HAVE BEEN ATTEMPTING TO EVADE US. WHEN QUERIED ABOUT THE CONFLICT ZJX REPLIED THAT ACFT WAS UNDER ZDC CTL AND THAT THEY DID NOT HAVE A DATA BLOCK ON HIM WITH HIS ALT. THEY LATER INFORMED US THAT HE WAS AT APPROX 26000' AND CLBING AS HE PASSED UNDER AND SLIGHTLY AFT OF US. A CONTRIBUTING FACTOR TO THIS WAS HAVING 2 ACFT IN THE SAME AIRSPACE BEING CTLED BY SEPARATE CENTERS.

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