ZDC controller issues clearance to wrong aircraft causing conflict with other en route aircraft.

Attributes
ACN	452685
Time
Date	199910
Day	Wed
Local Time Of Day	1801 To 2400
Place
Locale Reference	atc facility : zdc.artcc
State Reference	VA
Altitude	msl single value : 33000
Environment
Flight Conditions	VMC
Light	Dusk
Aircraft 1
Controlling Facilities	artcc : zdc.artcc
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Phase	cruise : enroute altitude change
Flight Plan	IFR
Aircraft 2
Controlling Facilities	artcc : zdc.artcc
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Phase	cruise : level
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Experience	controller limited radar : 11 controller radar : 10
ASRS Report	452685
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
Resolutory Action	controller : issued new clearance
Consequence	faa : investigated
Miss Distance	horizontal : 19000 vertical : 0
Supplementary
Problem Areas	ATC Human Performance Airspace Structure
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

Had 2 aircraft to phl, 1 aircraft X at FL350 and 1 aircraft Y at FL330. Intended to descend the FL330 down to FL290 prior to starting vectoring for in-trail, and unintentionally descended the aircraft at FL350 by mistake. When conflict alert started, turned the descending aircraft right to re-establish 5 mi.

Original NASA ASRS Text

Title: ZDC CTLR ISSUES CLRNC TO WRONG ACFT CAUSING CONFLICT WITH OTHER ENRTE ACFT.

Narrative: HAD 2 ACFT TO PHL, 1 ACFT X AT FL350 AND 1 ACFT Y AT FL330. INTENDED TO DSND THE FL330 DOWN TO FL290 PRIOR TO STARTING VECTORING FOR IN-TRAIL, AND UNINTENTIONALLY DSNDED THE ACFT AT FL350 BY MISTAKE. WHEN CONFLICT ALERT STARTED, TURNED THE DSNDING ACFT R TO RE-ESTABLISH 5 MI.

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.