Narrative:

I was the ojti on west radar. The trainee cleared aircraft X for visual approach/short approach to runway 21; four miles north of the field. It claimed it could not make the descent. I took the frequency at that time because of task saturation of the trainee. I told aircraft one to maneuver as necessary for descent. After dealing with other aircraft sequencing into a satellite airport; noticed aircraft X had crossed final and turned outbound; making a left 270 with aircraft Y on final descending through 3;000 ft approximately 4 miles in trail of aircraft X. I instructed aircraft Y to maintain 3;000 ft and turn away from aircraft X. Never give pilots permission to maneuver as necessary; be directive. Ojti should realize task saturation of trainee sooner.

Related reports:

Google
 

Original NASA ASRS Text

Title: CHS Controller described a conflict event when indicating to a visual approach aircraft to 'maneuver as necessary' due to altitude resulting in a conflict with a succeeding aircraft

Narrative: I was the OJTI on West RADAR. The trainee cleared aircraft X for visual approach/short approach to Runway 21; four miles north of the field. It claimed it could not make the descent. I took the frequency at that time because of task saturation of the trainee. I told aircraft one to maneuver as necessary for descent. After dealing with other aircraft sequencing into a satellite airport; noticed aircraft X had crossed final and turned outbound; making a left 270 with aircraft Y on final descending through 3;000 FT approximately 4 miles in trail of aircraft X. I instructed aircraft Y to maintain 3;000 FT and turn away from aircraft X. Never give pilots permission to maneuver as necessary; be directive. OJTI should realize task saturation of trainee sooner.

Data retrieved from NASA's ASRS site as of July 2013 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.