Air carrier X had less than standard separation from air carrier Y. System error.

Attributes
ACN	114699
Time
Date	198906
Day	Fri
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : fak
State Reference	VA
Altitude	msl bound lower : 31000 msl bound upper : 33000
Environment
Flight Conditions	VMC
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 descent other other
Route In Use	approach : circling arrival other enroute airway : zdc
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Large Transport, Low Wing, 3 Turbojet Eng
Flight Phase	cruise other other
Route In Use	approach : circling arrival other
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
ASRS Report	114699
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	conflict : airborne less severe non adherence : published procedure non adherence : required legal separation
Independent Detector	atc equipment other atc equipment : unspecified other controllera
Resolutory Action	controller : issued new clearance other
Consequence	faa : investigated
Miss Distance	horizontal : 24000 vertical : 800
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

WX front stationary on ewr and lga arrival routes caused holding. Traffic management unit (tmu alias 'flow control') brought new routes to sector. While putting new routes into computer and issuing new routes another 'new' set of routes was brought. (Also a 30 mi intrail single flow requirement.) while fixing routes again and vectoring 6 aircraft for spacing the receiving controller told me I had to 'keep' my traffic. 4 of the 6 were at FL330. I climbed and descended and gave holding instructions. Then tmu brought another route (that I couldn't read.) I thought that I had established vertical separation and turned my attention to the new routes, while talking to the area supervisor. I noticed 2 aircraft air carrier Y and air carrier X converging at FL330 (the aircraft were approximately 6 mi apart when I noticed them both at their assigned altitude at the same time that conflict alert activated). Air carrier X was issued an immediate descent clearance to FL310 and came within 4.0 mi and 800' of air carrier Y. Note: the new route tmu brought would not process in the computer. Note: I have been giving OJT for the last 6 months and have worked on my own less than a day a month at this sector.

Original NASA ASRS Text

Title: ACR X HAD LESS THAN STANDARD SEPARATION FROM ACR Y. SYSTEM ERROR.

Narrative: WX FRONT STATIONARY ON EWR AND LGA ARR ROUTES CAUSED HOLDING. TFC MGMNT UNIT (TMU ALIAS 'FLOW CONTROL') BROUGHT NEW ROUTES TO SECTOR. WHILE PUTTING NEW ROUTES INTO COMPUTER AND ISSUING NEW ROUTES ANOTHER 'NEW' SET OF ROUTES WAS BROUGHT. (ALSO A 30 MI INTRAIL SINGLE FLOW REQUIREMENT.) WHILE FIXING ROUTES AGAIN AND VECTORING 6 ACFT FOR SPACING THE RECEIVING CTLR TOLD ME I HAD TO 'KEEP' MY TFC. 4 OF THE 6 WERE AT FL330. I CLIMBED AND DESCENDED AND GAVE HOLDING INSTRUCTIONS. THEN TMU BROUGHT ANOTHER ROUTE (THAT I COULDN'T READ.) I THOUGHT THAT I HAD ESTABLISHED VERTICAL SEPARATION AND TURNED MY ATTN TO THE NEW ROUTES, WHILE TALKING TO THE AREA SUPVR. I NOTICED 2 ACFT ACR Y AND ACR X CONVERGING AT FL330 (THE ACFT WERE APPROX 6 MI APART WHEN I NOTICED THEM BOTH AT THEIR ASSIGNED ALT AT THE SAME TIME THAT CONFLICT ALERT ACTIVATED). ACR X WAS ISSUED AN IMMEDIATE DSCNT CLRNC TO FL310 AND CAME WITHIN 4.0 MI AND 800' OF ACR Y. NOTE: THE NEW ROUTE TMU BROUGHT WOULD NOT PROCESS IN THE COMPUTER. NOTE: I HAVE BEEN GIVING OJT FOR THE LAST 6 MONTHS AND HAVE WORKED ON MY OWN LESS THAN A DAY A MONTH AT THIS SECTOR.

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.