A80 controller experienced operational error involving two general aviation aircraft when one aircra...

Narrative:

I was working sat-P sector at A80 approach. I had aircraft X (C177) on a southbound vector to join the runway 20L localizer at pdk airport. I had aircraft Y (C172) on a westbound vector for the ILS 20L at pdk. Aircraft X was at 4;000 ft; aircraft Y was at 3;000 ft. I was busy at the time releasing aircraft off of pdk; lzu. I was also accomplishing coordination with ZTL. I issued aircraft X missed approach instructions of heading 090 degrees and altitude 3;000 ft as the aircraft was doing practice approaches. Aircraft X did not respond. I prompted the aircraft for a response by saying; 'aircraft X.' aircraft X responded; '090 and 3;000.' I heard what I thought was an appropriate readback of missed instructions. Aircraft X; however; turned and descended directly toward aircraft Y. When I recognized the situation; I turned aircraft X immediately to a 240 degree heading and aircraft Y to a 360 degree heading. Aircraft Y did not respond to my first transmission and had to be called again. Separation got down to 2.57 miles and 200 ft. I believe that my workload as well as both pilots' lack of attention contributed to my operational error. Aircraft X was not listening when I gave him missed approach procedures and aircraft Y was not paying attention when I gave a very critical vector. Atl and A80 airspace is some of the busiest in the world. Unless someone can get pilots to pay attention and remain actively engaged in their flight; then there is no remedy. I had an operational error that could easily have been prevented if: 1) aircraft X actively listened to instructions; or 2) aircraft Y heard my first transmission and turned in a timely manner. Lack of attention happens here by pilots daily -- not just GA; but air carrier pilots as well. People need to get their heads in the game as lives truly are at stake!

Original NASA ASRS Text

Title: A80 Controller experienced operational error involving two general aviation aircraft when one aircraft responded to missed approach instructions; turned and descended toward another aircraft; position workload and distractions listed as causal factors.

Narrative: I was working SAT-P sector at A80 approach. I had Aircraft X (C177) on a southbound vector to join the Runway 20L LOC at PDK Airport. I had Aircraft Y (C172) on a westbound vector for the ILS 20L at PDK. Aircraft X was at 4;000 FT; Aircraft Y was at 3;000 FT. I was busy at the time releasing aircraft off of PDK; LZU. I was also accomplishing coordination with ZTL. I issued Aircraft X missed approach instructions of heading 090 degrees and altitude 3;000 FT as the aircraft was doing practice approaches. Aircraft X did not respond. I prompted the aircraft for a response by saying; 'Aircraft X.' Aircraft X responded; '090 and 3;000.' I heard what I thought was an appropriate readback of missed instructions. Aircraft X; however; turned and descended directly toward Aircraft Y. When I recognized the situation; I turned Aircraft X immediately to a 240 degree heading and Aircraft Y to a 360 degree heading. Aircraft Y did not respond to my first transmission and had to be called again. Separation got down to 2.57 miles and 200 FT. I believe that my workload as well as both pilots' lack of attention contributed to my operational error. Aircraft X was not listening when I gave him missed approach procedures and Aircraft Y was not paying attention when I gave a very critical vector. ATL and A80 airspace is some of the busiest in the world. Unless someone can get pilots to pay attention and remain actively engaged in their flight; then there is no remedy. I had an operational error that could easily have been prevented if: 1) Aircraft X actively listened to instructions; or 2) Aircraft Y heard my first transmission and turned in a timely manner. Lack of attention happens here by pilots daily -- not just GA; but air carrier pilots as well. People need to get their heads in the game as lives truly are at stake!

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.

Attributes
ACN	826689
Time
Date	200903
Local Time Of Day	0601-1200
Place
Locale Reference	A80.TRACON
State Reference	GA
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	Cardinal 177/177RG
Operating Under FAR Part	Part 91
Flight Phase	Initial Approach
Route In Use	Vectors
Flight Plan	IFR
Aircraft 2
Make Model Name	Skyhawk 172/Cutlass 172
Operating Under FAR Part	Part 91
Flight Phase	Initial Approach
Route In Use	Vectors
Person 1
Function	Approach
Qualification	Air Traffic Control Fully Certified
Experience	Air Traffic Control Radar 12 Air Traffic Control Time Certified In Pos 1 (yrs) 2
Events
Anomaly	ATC Issue All Types
Miss Distance	Horizontal 15420 Vertical 200

A80 controller experienced operational error involving two general aviation aircraft when one aircraft responded to missed approach instructions; turned and descended toward another aircraft; position workload and distractions listed as causal factors.