Narrative:

Mlt X departed for a practice ILS approach. He was issued a heading of 330 degrees by the tower, and on contact with departure control was reissued 300 degree heading, which was acknowledged. My attention was then drawn to inbnds at the top of the scope. After taking care of several other calls I went back and then issued a 360 degree heading to mlt X. Again returning to the top of the scope to set up the inbnds, I was then suddenly called by a departing air carrier Y who had been assigned a 330 degree heading by the tower, but who appeared to be tracking 270 degrees on a collision course with the mlt X. I immediately issued air carrier Y a 360 degree heading and the mlt X a 270 degree heading to avoid collision. I feel this occurred because: 1) due to the bad WX, both aircraft delayed taking their assigned headings west/O advising ATC; 2) the tower controller should have seen the mlt X on his scope in conflict with air carrier Y's assigned heading; and 3) I should have noticed air carrier Y deviation sooner, but was engaged in setting up a complex approach sequence. Remedies: remind pilot to advise immediately if assigned heading won't be followed; better BRITE scanning from tower; and I should not have been working 2 sectors with that much traffic--it should have been split up.

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Original NASA ASRS Text

Title: A DEP ACR CONFLICTED WITH AN MLT IN CLOSE PROX TO THE ARPT.

Narrative: MLT X DEPARTED FOR A PRACTICE ILS APCH. HE WAS ISSUED A HDG OF 330 DEGS BY THE TWR, AND ON CONTACT WITH DEP CTL WAS REISSUED 300 DEG HDG, WHICH WAS ACKNOWLEDGED. MY ATTN WAS THEN DRAWN TO INBNDS AT THE TOP OF THE SCOPE. AFTER TAKING CARE OF SEVERAL OTHER CALLS I WENT BACK AND THEN ISSUED A 360 DEG HDG TO MLT X. AGAIN RETURNING TO THE TOP OF THE SCOPE TO SET UP THE INBNDS, I WAS THEN SUDDENLY CALLED BY A DEPARTING ACR Y WHO HAD BEEN ASSIGNED A 330 DEG HDG BY THE TWR, BUT WHO APPEARED TO BE TRACKING 270 DEGS ON A COLLISION COURSE WITH THE MLT X. I IMMEDIATELY ISSUED ACR Y A 360 DEG HDG AND THE MLT X A 270 DEG HDG TO AVOID COLLISION. I FEEL THIS OCCURRED BECAUSE: 1) DUE TO THE BAD WX, BOTH ACFT DELAYED TAKING THEIR ASSIGNED HDGS W/O ADVISING ATC; 2) THE TWR CTLR SHOULD HAVE SEEN THE MLT X ON HIS SCOPE IN CONFLICT WITH ACR Y'S ASSIGNED HDG; AND 3) I SHOULD HAVE NOTICED ACR Y DEVIATION SOONER, BUT WAS ENGAGED IN SETTING UP A COMPLEX APCH SEQUENCE. REMEDIES: REMIND PLT TO ADVISE IMMEDIATELY IF ASSIGNED HDG WON'T BE FOLLOWED; BETTER BRITE SCANNING FROM TWR; AND I SHOULD NOT HAVE BEEN WORKING 2 SECTORS WITH THAT MUCH TFC--IT SHOULD HAVE BEEN SPLIT UP.

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.