Narrative:

Training was in progress, on combined position. Traffic was light. King air X was instructed to descend and maintain 7000 ft. King air was observed 2 mins later to be at 6000 ft on a conflicting course with the C340 (aircraft Y). I pointed this situation out to my developmental, who took inadequate action to avert loss of separation. To avoid in future, I will take action instead of leaving it to the trainee. When the situation was recognized, there were 8 mi between the 2 aircraft. I felt it was enough room to get the 2 planes to miss, but the king air was only turned 15 degrees to the right, and the C340 not at all. By the time I saw my developmental's plan was going to fail, separation had been lost. Readback/hearback not a factor. King air pilot read back 7000 ft.

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Original NASA ASRS Text

Title: TRACON TRAINEE ISSUES INSUFFICIENT TURN TO PROVIDE LEGAL SEPARATION BTWN DSNDING BE90 AND C340. RADAR INSTRUCTOR OBSERVES SIT, BUT DOES NOT REACT IN TIM TO APPLY PROPER SEPARATION.

Narrative: TRAINING WAS IN PROGRESS, ON COMBINED POS. TFC WAS LIGHT. KING AIR X WAS INSTRUCTED TO DSND AND MAINTAIN 7000 FT. KING AIR WAS OBSERVED 2 MINS LATER TO BE AT 6000 FT ON A CONFLICTING COURSE WITH THE C340 (ACFT Y). I POINTED THIS SIT OUT TO MY DEVELOPMENTAL, WHO TOOK INADEQUATE ACTION TO AVERT LOSS OF SEPARATION. TO AVOID IN FUTURE, I WILL TAKE ACTION INSTEAD OF LEAVING IT TO THE TRAINEE. WHEN THE SIT WAS RECOGNIZED, THERE WERE 8 MI BTWN THE 2 ACFT. I FELT IT WAS ENOUGH ROOM TO GET THE 2 PLANES TO MISS, BUT THE KING AIR WAS ONLY TURNED 15 DEGS TO THE R, AND THE C340 NOT AT ALL. BY THE TIME I SAW MY DEVELOPMENTAL'S PLAN WAS GOING TO FAIL, SEPARATION HAD BEEN LOST. READBACK/HEARBACK NOT A FACTOR. KING AIR PLT READ BACK 7000 FT.

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.