Controller descended aircraft through the altitude of opposite direction traffic. Operational error.

Attributes
ACN	102742
Time
Date	198901
Day	Wed
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : cyn
State Reference	NJ
Altitude	msl bound lower : 15000 msl bound upper : 17000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zny
Operator	common carrier : air carrier
Make Model Name	Widebody, Low Wing, 3 Turbojet Eng
Navigation In Use	Other
Flight Phase	cruise other
Route In Use	enroute : direct
Flight Plan	IFR
Aircraft 2
Operator	other
Make Model Name	Military Transport
Flight Phase	descent other
Route In Use	enroute : direct
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Experience	controller non radar : 5 controller radar : 3
ASRS Report	102742
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
Consequence	faa : investigated
Miss Distance	horizontal : 6000 vertical : 400
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

I was descending a navy MTR down reference a medium large transport which was heading in the same direction and just lost sight of opp direction traffic at the same altitude. Callback conversation with reporter revealed following information. Reporter advised the incident occurred 20 miles east of cyn at 16000'. A northbound MTR was descended from 17000' to 15000'. The controller forgot about a widebody transport southbound at 16000' and separation was lost. Conflict alert alarmed. The controller was working the sector alone with a data controller assigned to assist.

Original NASA ASRS Text

Title: CTLR DESCENDED ACFT THROUGH THE ALT OF OPPOSITE DIRECTION TRAFFIC. OPERATIONAL ERROR.

Narrative: I WAS DSNDING A NAVY MTR DOWN REFERENCE A MLG WHICH WAS HDG IN THE SAME DIRECTION AND JUST LOST SIGHT OF OPP DIRECTION TFC AT THE SAME ALT. CALLBACK CONVERSATION WITH RPTR REVEALED FOLLOWING INFO. RPTR ADVISED THE INCIDENT OCCURRED 20 MILES E OF CYN AT 16000'. A NBOUND MTR WAS DSNDED FROM 17000' TO 15000'. THE CTLR FORGOT ABOUT A WDB SBND AT 16000' AND SEPARATION WAS LOST. CONFLICT ALERT ALARMED. THE CTLR WAS WORKING THE SECTOR ALONE WITH A DATA CTLR ASSIGNED TO ASSIST.

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.