Narrative:

Cpr X was sebound on J34 air J80 eastbound landing thv. The second plane air carrier Y was wbound on J80 landing at stl. Here was another air carrier flight at 350 parallel to air carrier Y slowly overtaking him, also landing at stl. Prior to this there were approximately 4 flts landing in the dca-iad-bwi area flying through. These flts usually come sebound on J34 just like cpr X. I thought cpr X was another washington area airplane. The radar controller had run out his 8 min vector lines and if cpr X had continued onto the washington area he was no factor with air carrier Y. Cpr X turned eastbound onto J80 at air, approximately 2 mins later they passed each other at 1.4 mi apart. The radar controller gave air carrier Y a right turn. He didn't respond. He then turned cpr X to the right. The conflict alert initially went off at 3.9 mi apart.

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Original NASA ASRS Text

Title: CPR X HAD LTSS FROM ACR Y. SYS ERROR.

Narrative: CPR X WAS SEBOUND ON J34 AIR J80 EBOUND LNDG THV. THE SECOND PLANE ACR Y WAS WBOUND ON J80 LNDG AT STL. HERE WAS ANOTHER ACR FLT AT 350 PARALLEL TO ACR Y SLOWLY OVERTAKING HIM, ALSO LNDG AT STL. PRIOR TO THIS THERE WERE APPROX 4 FLTS LNDG IN THE DCA-IAD-BWI AREA FLYING THROUGH. THESE FLTS USUALLY COME SEBOUND ON J34 JUST LIKE CPR X. I THOUGHT CPR X WAS ANOTHER WASHINGTON AREA AIRPLANE. THE RADAR CTLR HAD RUN OUT HIS 8 MIN VECTOR LINES AND IF CPR X HAD CONTINUED ONTO THE WASHINGTON AREA HE WAS NO FACTOR WITH ACR Y. CPR X TURNED EBOUND ONTO J80 AT AIR, APPROX 2 MINS LATER THEY PASSED EACH OTHER AT 1.4 MI APART. THE RADAR CTLR GAVE ACR Y A R TURN. HE DIDN'T RESPOND. HE THEN TURNED CPR X TO THE R. THE CONFLICT ALERT INITIALLY WENT OFF AT 3.9 MI APART.

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.