Narrative:

While conducting OJT on S46 departure west (Y), my developmental accepted a handoff from nuw (navy whidbey) approach control on aircraft X at 9000 ft. Coincidentally, nuw had accepted a handoff on aircraft Y, a PA32 at 8000 ft, opposite direction. When aircraft X checked in, he reported at '8 1/2 mi for 6000 ft.' my developmental replied with 'roger.' I immediately asked aircraft X his altitude and issued an immediate left turn to 090 degrees to avoid the traffic now at his 12 O'clock position and less than 3 mi. Aircraft X did not acknowledge. I restated the instruction and again received no acknowledgement. A third query found aircraft X now past the conflicting traffic. He crossed over him at 8300 ft. There was an apparent miscom between aircraft X and the controller at nuw which I have not been fully briefed on. Traffic in my sector was light to moderate and I was explaining some other issues to my developmental at the time of the occurrence which may have distraction him.

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Original NASA ASRS Text

Title: WHILE PROVIDING TRAINING, S46 CTLR OBSERVES ACR TURBOPROP DSND FROM COORD FLT PROGRESS STRIP ALT IN CONFLICT WITH OPPOSITE DIRECTION PA32.

Narrative: WHILE CONDUCTING OJT ON S46 DEP W (Y), MY DEVELOPMENTAL ACCEPTED A HDOF FROM NUW (NAVY WHIDBEY) APCH CTL ON ACFT X AT 9000 FT. COINCIDENTALLY, NUW HAD ACCEPTED A HDOF ON ACFT Y, A PA32 AT 8000 FT, OPPOSITE DIRECTION. WHEN ACFT X CHKED IN, HE RPTED AT '8 1/2 MI FOR 6000 FT.' MY DEVELOPMENTAL REPLIED WITH 'ROGER.' I IMMEDIATELY ASKED ACFT X HIS ALT AND ISSUED AN IMMEDIATE L TURN TO 090 DEGS TO AVOID THE TFC NOW AT HIS 12 O'CLOCK POS AND LESS THAN 3 MI. ACFT X DID NOT ACKNOWLEDGE. I RESTATED THE INSTRUCTION AND AGAIN RECEIVED NO ACKNOWLEDGEMENT. A THIRD QUERY FOUND ACFT X NOW PAST THE CONFLICTING TFC. HE CROSSED OVER HIM AT 8300 FT. THERE WAS AN APPARENT MISCOM BTWN ACFT X AND THE CTLR AT NUW WHICH I HAVE NOT BEEN FULLY BRIEFED ON. TFC IN MY SECTOR WAS LIGHT TO MODERATE AND I WAS EXPLAINING SOME OTHER ISSUES TO MY DEVELOPMENTAL AT THE TIME OF THE OCCURRENCE WHICH MAY HAVE DISTR HIM.

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.