Less than standard separation between air carrier and corp jet. Operational error.

Attributes
ACN	100299
Time
Date	198812
Day	Fri
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : uin
State Reference	IL
Altitude	msl bound lower : 29800 msl bound upper : 31000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zkc
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	climbout : intermediate altitude descent other
Route In Use	enroute airway : j80
Flight Plan	IFR
Aircraft 2
Operator	general aviation : corporate
Make Model Name	Light Transport, Low Wing, 2 Turbojet Eng
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
ASRS Report	100299
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	conflict : airborne less severe non adherence : required legal separation
Independent Detector	atc equipment other atc equipment : unspecified
Resolutory Action	controller : issued new clearance
Consequence	faa : investigated
Miss Distance	horizontal : 15000 vertical : 1200
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

Air carrier X checked on frequency and was climbed to FL290 for crossing traffic at FL310. There was additional traffic crossing at FL330. Corp Y was coming northeast bound from another sector at FL330 which was in conflict with the previously described traffic at FL330. Control for lower was received from the transferring sector and when Y called on frequency at FL330, he was descended to FL310 solving the confliction with the other traffic at FL330. Also descending corp Y to FL310, kept him separated from X which was also crossing traffic for Y. When air carrier X was clear of his original traffic at FL310 and FL330, I climbed him to his requested altitude of FL330, not realizing corp Y was still traffic for X. C/a was activated as soon as X showed a climb. I descended X back to FL290 but as X and Y were already within 5 mi of each other, the operational error had already occurred. No evasive action was taken as air carrier X reported out of FL298 for FL290. I believe a lack of concentration was demonstrated on my part after working several other aircraft just before.

Original NASA ASRS Text

Title: LESS THAN STANDARD SEPARATION BETWEEN ACR AND CORP JET. OPERATIONAL ERROR.

Narrative: ACR X CHKED ON FREQ AND WAS CLBED TO FL290 FOR XING TFC AT FL310. THERE WAS ADDITIONAL TFC XING AT FL330. CORP Y WAS COMING NE BOUND FROM ANOTHER SECTOR AT FL330 WHICH WAS IN CONFLICT WITH THE PREVIOUSLY DESCRIBED TFC AT FL330. CONTROL FOR LOWER WAS RECEIVED FROM THE TRANSFERRING SECTOR AND WHEN Y CALLED ON FREQ AT FL330, HE WAS DSNDED TO FL310 SOLVING THE CONFLICTION WITH THE OTHER TFC AT FL330. ALSO DSNDING CORP Y TO FL310, KEPT HIM SEPARATED FROM X WHICH WAS ALSO XING TFC FOR Y. WHEN ACR X WAS CLR OF HIS ORIGINAL TFC AT FL310 AND FL330, I CLBED HIM TO HIS REQUESTED ALT OF FL330, NOT REALIZING CORP Y WAS STILL TFC FOR X. C/A WAS ACTIVATED AS SOON AS X SHOWED A CLB. I DSNDED X BACK TO FL290 BUT AS X AND Y WERE ALREADY WITHIN 5 MI OF EACH OTHER, THE OPERROR HAD ALREADY OCCURRED. NO EVASIVE ACTION WAS TAKEN AS ACR X RPTED OUT OF FL298 FOR FL290. I BELIEVE A LACK OF CONCENTRATION WAS DEMONSTRATED ON MY PART AFTER WORKING SEVERAL OTHER ACFT JUST BEFORE.

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.