Shv controller experienced operational error at 12000 ft with en route and descending aircraft.

Attributes
ACN	625133
Time
Date	200407
Day	Wed
Local Time Of Day	1201 To 1800
Place
Locale Reference	navaid : bad.vortac
State Reference	LA
Altitude	msl bound lower : 12000 msl bound upper : 13900
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : shv.tracon
Operator	other
Make Model Name	Stratofortress (B-52)
Operating Under FAR Part	Part 91
Flight Phase	cruise : level
Flight Plan	IFR
Aircraft 2
Controlling Facilities	tracon : shv.tracon
Make Model Name	Beechjet 400
Flight Phase	descent : intermediate altitude descent : vacating altitude
Person 1
Affiliation	government : faa
Function	controller : approach
Qualification	controller : radar
Experience	controller radar : 12
ASRS Report	625133
Person 2
Affiliation	government : military
Function	flight crew : captain oversight : pic
Events
Anomaly	conflict : airborne less severe non adherence : required legal separation
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance flight crew : took evasive action
Consequence	faa : investigated
Miss Distance	horizontal : 16200 vertical : 500
Supplementary
Problem Areas	ATC Human Performance
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

An HB52 was on frequency at 12000 ft eastbound. A beechjet reported on frequency at 13900 ft descending to 13000 ft requesting lower. I descended the beech jet to 5000 ft for an approach into shv. My attention was diverted by a C130 departure off of shv nebound climbing to 12000 ft. I then amended the C130's altitude to 11000 ft because of a potential conflict between the B52 and the C130. I then realized the beechjet was on a converging course with the B52 and immediately took corrective action but separation was lost.

Original NASA ASRS Text

Title: SHV CTLR EXPERIENCED OPERROR AT 12000 FT WITH ENRTE AND DSNDING ACFT.

Narrative: AN HB52 WAS ON FREQ AT 12000 FT EBOUND. A BEECHJET RPTED ON FREQ AT 13900 FT DSNDING TO 13000 FT REQUESTING LOWER. I DSNDED THE BEECH JET TO 5000 FT FOR AN APCH INTO SHV. MY ATTN WAS DIVERTED BY A C130 DEP OFF OF SHV NEBOUND CLBING TO 12000 FT. I THEN AMENDED THE C130'S ALT TO 11000 FT BECAUSE OF A POTENTIAL CONFLICT BTWN THE B52 AND THE C130. I THEN REALIZED THE BEECHJET WAS ON A CONVERGING COURSE WITH THE B52 AND IMMEDIATELY TOOK CORRECTIVE ACTION BUT SEPARATION WAS LOST.

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.