Narrative:

We were on a runway xx/yy configuration advertising visual approach. I was working the parallels runway xxr/xxl. The traffic was moderate to heavy and complex at times. Aircraft X was level at 4000' heading 040 left base runway xxl; 210kts had reported airport in sight. Aircraft Y level 4000' heading 210; right base runway xxr; 190kts. I turned aircraft X left heading 320 and cleared for visual approach runway xxl. Aircraft X acknowledged visual approach clearance. I then turned aircraft Y right heading 280 and reduce speed to 170kts. No response from aircraft Y. Restated instructions to aircraft Y to turn right heading 290 and to reduce speed to 170 kts. After second attempt realized I had a stuck mike. I attempted to descend aircraft X immediately to 3000' twice; but received no response. I then instructed aircraft Y to descend and maintain 3000' and to fly present heading. Received a garbled response. I then issue traffic to aircraft Y and received a garbled response. I instructed aircraft Y to maintain visual separation from the traffic. Aircraft Y responded; but the transmission was garbled and I all I heard was visual separation. Aircraft Y descend to 3000' and turned right crossing both finals approximately 2 miles in trail of aircraft X who was descending out of 4000' to join the runway xxr final. I had not issued a visual approach clearance to aircraft Y. Further talking to the pilot he said he was maintaining visual separation from aircraft X. All aircraft were on one frequency (119.3) and the stuck mike lasted for approximately 1 minute 54 seconds. Recommendation; the only thing that comes to mind was to leave one aircraft at 5000'.

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Original NASA ASRS Text

Title: TRACON Controller vectoring aircraft on opposite direction base turns for visual approaches to parallel runways experienced a 'stuck mike' render communications inoperable during a critical separation phase.

Narrative: We were on a Runway XX/YY configuration advertising visual approach. I was working the parallels Runway XXR/XXL. The traffic was moderate to heavy and complex at times. Aircraft X was level at 4000' heading 040 left base Runway XXL; 210kts had reported airport in sight. Aircraft Y level 4000' heading 210; Right base Runway XXR; 190kts. I turned Aircraft X left heading 320 and cleared for Visual Approach Runway XXL. Aircraft X acknowledged Visual Approach clearance. I then turned Aircraft Y right heading 280 and reduce speed to 170kts. No response from Aircraft Y. Restated instructions to Aircraft Y to turn right heading 290 and to reduce speed to 170 kts. After second attempt realized I had a stuck mike. I attempted to descend Aircraft X immediately to 3000' twice; but received no response. I then instructed Aircraft Y to descend and maintain 3000' and to fly present heading. Received a garbled response. I then issue traffic to Aircraft Y and received a garbled response. I instructed Aircraft Y to maintain Visual Separation from the traffic. Aircraft Y responded; but the transmission was garbled and I all I heard was visual separation. Aircraft Y descend to 3000' and turned right crossing both finals approximately 2 miles in trail of Aircraft X who was descending out of 4000' to join the Runway XXR final. I had not issued a Visual Approach clearance to Aircraft Y. Further talking to the pilot he said he was maintaining visual separation from Aircraft X. All aircraft were on one frequency (119.3) and the stuck mike lasted for approximately 1 minute 54 seconds. Recommendation; the only thing that comes to mind was to leave one aircraft at 5000'.

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.