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

Attributes
ACN	178963
Time
Date	199105
Day	Tue
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : aml
State Reference	VA
Altitude	msl bound lower : 16000 msl bound upper : 16000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zdc
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	descent other
Route In Use	enroute : on vectors
Flight Plan	IFR
Aircraft 2
Operator	general aviation : corporate
Make Model Name	Light Transport, Low Wing, 2 Turbojet Eng
Flight Phase	cruise other
Route In Use	enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Experience	controller radar : 22 controller supervisory : 10
ASRS Report	178963
Person 2
Affiliation	government : faa
Function	controller : flight data
Qualification	controller : non radar
Events
Anomaly	conflict : airborne less severe non adherence : published procedure non adherence : required legal separation
Independent Detector	atc equipment other atc equipment : unspecified
Resolutory Action	none taken : anomaly accepted
Consequence	faa : investigated
Miss Distance	horizontal : 18000 vertical : 0
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

Air carrier X was being descended to eventually cross doccs at 110, which is an arrival fix for iad/dca/adw. I also had cpr Y at 170 from over mol lan mrb northbound to mdt. My intention was to turn cpr Y earlier to the east and descend to 15. (Turboprop aircraft en route to har/lrp cross 10 mi south of lan at 150 and are fed to iadz). This way air carrier X would be off his left several mi descending to 110. All would have been fine except in my estimation, the event which just took place sort of blew my timing all to hell. I turned cpr Y a little too late and he and air carrier X passed with less than standard separation. The sector was extremely busy at the time with many propeller arrs coming from 2 different directions which have to be fed over 1 fix. This sector (csn) handles jets (FL110 altitudes) and propellers (090) destined iad, jets destined dca/adw (FL150) and jets destined bwi (FL190) over csn. This is the busiest time of day for this sector which I might add, only lasts for about 30 mins. Add to this that my D side controller had been recently checked out as a D controller only.

Original NASA ASRS Text

Title: ACR X HAD LTSS FROM CPR Y. SYS ERROR.

Narrative: ACR X WAS BEING DSNDED TO EVENTUALLY CROSS DOCCS AT 110, WHICH IS AN ARR FIX FOR IAD/DCA/ADW. I ALSO HAD CPR Y AT 170 FROM OVER MOL LAN MRB NBOUND TO MDT. MY INTENTION WAS TO TURN CPR Y EARLIER TO THE E AND DSND TO 15. (TURBOPROP ACFT ENRTE TO HAR/LRP CROSS 10 MI S OF LAN AT 150 AND ARE FED TO IADZ). THIS WAY ACR X WOULD BE OFF HIS L SEVERAL MI DSNDING TO 110. ALL WOULD HAVE BEEN FINE EXCEPT IN MY ESTIMATION, THE EVENT WHICH JUST TOOK PLACE SORT OF BLEW MY TIMING ALL TO HELL. I TURNED CPR Y A LITTLE TOO LATE AND HE AND ACR X PASSED WITH LTSS. THE SECTOR WAS EXTREMELY BUSY AT THE TIME WITH MANY PROP ARRS COMING FROM 2 DIFFERENT DIRECTIONS WHICH HAVE TO BE FED OVER 1 FIX. THIS SECTOR (CSN) HANDLES JETS (FL110 ALTS) AND PROPS (090) DESTINED IAD, JETS DESTINED DCA/ADW (FL150) AND JETS DESTINED BWI (FL190) OVER CSN. THIS IS THE BUSIEST TIME OF DAY FOR THIS SECTOR WHICH I MIGHT ADD, ONLY LASTS FOR ABOUT 30 MINS. ADD TO THIS THAT MY D SIDE CTLR HAD BEEN RECENTLY CHKED OUT AS A D CTLR ONLY.

Data retrieved from NASA's ASRS site as of July 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.