Less than standard separation between 2 air carrier. Operational error.

Attributes
ACN	102441
Time
Date	198901
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : rdu
State Reference	NC
Altitude	msl bound lower : 33000 msl bound upper : 33000
Environment
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zdc
Operator	common carrier : air carrier
Make Model Name	Large Transport, Low Wing, 3 Turbojet Eng
Flight Phase	cruise other
Route In Use	enroute airway : j209 enroute airway : j165
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Large Transport, Low Wing, 3 Turbojet Eng
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
ASRS Report	102441
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	conflict : airborne less severe non adherence : required legal separation
Independent Detector	atc equipment other atc equipment : unspecified
Resolutory Action	none taken : insufficient time
Consequence	faa : investigated
Miss Distance	horizontal : 23400 vertical : 0
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

One aircraft eastbound J209 20 NM east of rdu. Other aircraft northbound J165 east or rdu. Both aircraft at FL330. C/a activated when the aircraft were approximately 10 NM apart, and that was the first time I realized I had a problem. I do not know why I failed to see the potential earlier. I should have. I had the eastbound aircraft turn north and the northbound aircraft turn east. Sep decreased to 3.9 mi before increasing again. A contributing factor was a potential conflict occurring elsewhere between an aircraft in my sector and one in another sector. I obviously permitted my attention to be devoted to that situation too long, but had I seen the potential conflict that this report is about when I should have, then corrective action could have been working while the other problem was being resolved. Seems to me that C/a should be modified to give sufficient warning to avoid system error. In this case I did not have sufficient warning.

Original NASA ASRS Text

Title: LESS THAN STANDARD SEPARATION BETWEEN 2 ACR. OPERATIONAL ERROR.

Narrative: ONE ACFT EBND J209 20 NM E OF RDU. OTHER ACFT NBOUND J165 E OR RDU. BOTH ACFT AT FL330. C/A ACTIVATED WHEN THE ACFT WERE APPROX 10 NM APART, AND THAT WAS THE FIRST TIME I REALIZED I HAD A PROB. I DO NOT KNOW WHY I FAILED TO SEE THE POTENTIAL EARLIER. I SHOULD HAVE. I HAD THE EBND ACFT TURN N AND THE NBOUND ACFT TURN E. SEP DECREASED TO 3.9 MI BEFORE INCREASING AGAIN. A CONTRIBUTING FACTOR WAS A POTENTIAL CONFLICT OCCURRING ELSEWHERE BTWN AN ACFT IN MY SECTOR AND ONE IN ANOTHER SECTOR. I OBVIOUSLY PERMITTED MY ATTN TO BE DEVOTED TO THAT SITUATION TOO LONG, BUT HAD I SEEN THE POTENTIAL CONFLICT THAT THIS RPT IS ABOUT WHEN I SHOULD HAVE, THEN CORRECTIVE ACTION COULD HAVE BEEN WORKING WHILE THE OTHER PROB WAS BEING RESOLVED. SEEMS TO ME THAT C/A SHOULD BE MODIFIED TO GIVE SUFFICIENT WARNING TO AVOID SYS ERROR. IN THIS CASE I DID NOT HAVE SUFFICIENT WARNING.

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.