Less than standard separation between two atx aircraft. Operational erorr.

Attributes
ACN	105970
Time
Date	198903
Day	Tue
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : cll
State Reference	TX
Altitude	msl bound lower : 3000 msl bound upper : 3000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zhu
Operator	common carrier : air taxi
Make Model Name	Small Transport, Low Wing, 2 Turboprop Eng
Flight Phase	climbout : intermediate altitude
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air taxi
Make Model Name	Medium Transport, Low Wing, 2 Turbojet Eng
Flight Phase	descent other
Route In Use	approach : visual enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Experience	controller non radar : 3 controller radar : 5
ASRS Report	105970
Person 2
Affiliation	company : air taxi
Function	flight crew : captain oversight : pic
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	conflict : airborne less severe non adherence : required legal separation
Independent Detector	other controllera
Resolutory Action	none taken : anomaly accepted
Consequence	faa : investigated
Miss Distance	horizontal : 27000 vertical : 0
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

I cleared atx Y for a visual approach after receiving a visual contact report from both aircraft, and also a report that atx Y was 'past' the other aircraft that was traffic. I then cleared atx Y for a visual approach and told the pilot to maintain visual separation from the other traffic (aircraft X). Callback conversation with reporter revealed following information. Reporter gave years in ATC. Described types of aircraft ATC X was inbound while atx Y was a departure. Says they passed opp direction and then he cleared Y for visual approach. When Y left 4000' the vertical separation was lost but aircraft were going away from each other. Reporter had another operation error 6 weeks earlier and was suspended for a time period. Now since second incident has been put into training department for retraining. Says he has poor relationship with facility management. Closest aircraft got at same altitude was about 4.5 mile.

Original NASA ASRS Text

Title: LESS THAN STANDARD SEPARATION BETWEEN TWO ATX ACFT. OPERATIONAL ERORR.

Narrative: I CLRED ATX Y FOR A VISUAL APCH AFTER RECEIVING A VISUAL CONTACT RPT FROM BOTH ACFT, AND ALSO A RPT THAT ATX Y WAS 'PAST' THE OTHER ACFT THAT WAS TFC. I THEN CLRED ATX Y FOR A VISUAL APCH AND TOLD THE PLT TO MAINTAIN VISUAL SEPARATION FROM THE OTHER TFC (ACFT X). CALLBACK CONVERSATION WITH RPTR REVEALED FOLLOWING INFO. RPTR GAVE YEARS IN ATC. DESCRIBED TYPES OF ACFT ATC X WAS INBND WHILE ATX Y WAS A DEP. SAYS THEY PASSED OPP DIRECTION AND THEN HE CLRED Y FOR VISUAL APCH. WHEN Y LEFT 4000' THE VERTICAL SEPARATION WAS LOST BUT ACFT WERE GOING AWAY FROM EACH OTHER. RPTR HAD ANOTHER OP ERROR 6 WEEKS EARLIER AND WAS SUSPENDED FOR A TIME PERIOD. NOW SINCE SECOND INCIDENT HAS BEEN PUT INTO TRAINING DEPT FOR RETRAINING. SAYS HE HAS POOR RELATIONSHIP WITH FAC MGMNT. CLOSEST ACFT GOT AT SAME ALT WAS ABOUT 4.5 MILE.

Data retrieved from NASA's ASRS site as of August 2007 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.