ZOB radar controller failed to observe conflicting traffic resulting in loss of separation.

Attributes
ACN	579654
Time
Date	200304
Day	Thu
Local Time Of Day	0601 To 1200
Place
State Reference	OH
Altitude	msl bound lower : 11000 msl bound upper : 12000
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zob.artcc
Operator	general aviation : corporate
Make Model Name	Citation II S2/Bravo
Operating Under FAR Part	Part 91
Flight Phase	climbout : intermediate altitude
Flight Plan	IFR
Aircraft 2
Controlling Facilities	artcc : zob.artcc
Operator	common carrier : air carrier
Make Model Name	SF 340A
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 military : 5 controller radar : 5
ASRS Report	579654
Person 2
Affiliation	company : corporate
Function	flight crew : captain oversight : pic
Events
Anomaly	conflict : airborne critical non adherence : required legal separation
Independent Detector	atc equipment : conflict alert other controllera
Resolutory Action	none taken : insufficient time
Consequence	faa : investigated
Miss Distance	horizontal : 24000 vertical : 4000
Supplementary
Problem Areas	ATC Human Performance
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

C550 aircraft climbed to 11000 ft sbound. Traffic aircraft wbound at 12000 ft. Climbed C550 aircraft sbound through occupied altitude after overlooking wbound aircraft.

Original NASA ASRS Text

Title: ZOB RADAR CTLR FAILED TO OBSERVE CONFLICTING TFC RESULTING IN LOSS OF SEPARATION.

Narrative: C550 ACFT CLBED TO 11000 FT SBOUND. TFC ACFT WBOUND AT 12000 FT. CLBED C550 ACFT SBOUND THROUGH OCCUPIED ALT AFTER OVERLOOKING WBOUND ACFT.

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.