Less than standard separation between corp jet and jet atx. Operational error.

Attributes
ACN	100510
Time
Date	198812
Day	Thu
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : tth
State Reference	IN
Altitude	msl bound lower : 29000 msl bound upper : 29600
Environment
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zau
Operator	general aviation : corporate
Make Model Name	Light Transport, Low Wing, 2 Turbojet Eng
Flight Phase	climbout : intermediate altitude
Route In Use	enroute : direct enroute airway : j173
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air taxi
Make Model Name	Small Transport, Low Wing, 2 Turbojet Eng
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Experience	controller radar : 2
ASRS Report	100510
Person 2
Affiliation	Other
Function	flight crew : captain oversight : pic
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	conflict : airborne less severe non adherence : required legal separation
Independent Detector	other other : unspecified atc
Resolutory Action	controller : issued new clearance other
Consequence	faa : investigated
Miss Distance	horizontal : 27000 vertical : 600
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

The problem arose when I miscalculated the rate of climb of corp X and the overflt at FL290. I turned X toward his destination thinking he would be out of FL310. I also failed to realize the degree of turn would be 30 degree or more toward his destination. I realized the error after coordinating a route change on the landline with the adjacent center. Once I realized that corp X turned left further than I anticipated, I called X to turn back to a south heading but received no response. I then turned corp Y left of his course, and once again tried to reach aircraft X with no response. Corp X then called asking if the heading was for him. I said affirmative fly heading 180 for traffic. At this time lateral separation was lost and the error occurred. I feel that if corp X would have turned when I told him to I might have saved the error.

Original NASA ASRS Text

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

Narrative: THE PROBLEM AROSE WHEN I MISCALCULATED THE RATE OF CLIMB OF CORP X AND THE OVERFLT AT FL290. I TURNED X TOWARD HIS DEST THINKING HE WOULD BE OUT OF FL310. I ALSO FAILED TO REALIZE THE DEGREE OF TURN WOULD BE 30 DEG OR MORE TOWARD HIS DEST. I REALIZED THE ERROR AFTER COORDINATING A ROUTE CHANGE ON THE LANDLINE WITH THE ADJACENT CENTER. ONCE I REALIZED THAT CORP X TURNED LEFT FURTHER THAN I ANTICIPATED, I CALLED X TO TURN BACK TO A SOUTH HDG BUT RECEIVED NO RESPONSE. I THEN TURNED CORP Y LEFT OF HIS COURSE, AND ONCE AGAIN TRIED TO REACH ACFT X WITH NO RESPONSE. CORP X THEN CALLED ASKING IF THE HDG WAS FOR HIM. I SAID AFFIRMATIVE FLY HDG 180 FOR TFC. AT THIS TIME LATERAL SEPARATION WAS LOST AND THE ERROR OCCURRED. I FEEL THAT IF CORP X WOULD HAVE TURNED WHEN I TOLD HIM TO I MIGHT HAVE SAVED THE ERROR.

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.