Narrative:

I was providing OJT. Aircraft were on sids. Trainee apparently thought separation was going to be lost and actually created the loss of separation by initiating vectors. If trainee had just let the aircraft fly their respective courses separation would have been kept. I; as the instructor; did not cut off the transmission immediately to avert the loss of separation. This is my first trainee in many years. Recommendation; do not wait to cut off trainees' clearance to aircraft.

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Original NASA ASRS Text

Title: SCT Controller providing OJT was late in intervening when the student elected to vector traffic off the SID; creating a loss of separation.

Narrative: I was providing OJT. Aircraft were on SIDs. Trainee apparently thought separation was going to be lost and actually created the loss of separation by initiating vectors. If trainee had just let the aircraft fly their respective courses separation would have been kept. I; as the Instructor; did not cut off the transmission immediately to avert the loss of separation. This is my first trainee in many years. Recommendation; do not wait to cut off trainees' clearance to aircraft.

Data retrieved from NASA's ASRS site as of April 2012 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.