TRACON controller working combined positions with heavy traffic reported a TCAS RA event when failin...

Attributes
ACN	982587
Time
Date	201112
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZ.TRACON
State Reference	US
Aircraft 1
Make Model Name	Regional Jet 200 ER/LR (CRJ200)
Operating Under FAR Part	Part 121
Flight Phase	Final Approach
Route In Use	Vectors
Flight Plan	IFR
Aircraft 2
Make Model Name	Regional Jet CL65 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	Final Approach
Route In Use	Visual Approach
Flight Plan	IFR
Person 1
Function	Approach Departure
Qualification	Air Traffic Control Fully Certified
Events
Anomaly	ATC Issue All Types Conflict Airborne Conflict

Narrative:

I was working 3 final positions combined in the early morning on a large arrival bank. I was distracted by another aircraft that checked in and caused me to be late on my visual approach clearance to aircraft X. I did not ensure proper altitude separation from opposite bases and was betting that I would clear the opposing base traffic for the visual approach before separation was lost. Aircraft Y directly under flew aircraft X while descending to 3;000 and aircraft X responded to an RA by climbing. I resolved the situation by breaking aircraft X out to the east and re sequencing the aircraft. Both airplanes had the airport in sight but I never cleared either. I would recommend I follow procedures and/or not allow all finals to be combined while working 14-15 aircraft on final.

Original NASA ASRS Text

Title: TRACON Controller working combined positions with heavy traffic reported a TCAS RA event when failing to insure separation.

Narrative: I was working 3 final positions combined in the early morning on a large arrival bank. I was distracted by another aircraft that checked in and caused me to be late on my Visual Approach clearance to Aircraft X. I did not ensure proper altitude separation from opposite bases and was betting that I would clear the opposing base traffic for the visual approach before separation was lost. Aircraft Y directly under flew Aircraft X while descending to 3;000 and Aircraft X responded to an RA by climbing. I resolved the situation by breaking Aircraft X out to the east and re sequencing the aircraft. Both airplanes had the airport in sight but I never cleared either. I would recommend I follow procedures and/or not allow all finals to be combined while working 14-15 aircraft on final.

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.

TRACON controller working combined positions with heavy traffic reported a TCAS RA event when failing to insure separation.