2 aircraft at same altitude with less than standard separation. System error.

Attributes
ACN	115106
Time
Date	198906
Day	Mon
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : ste
State Reference	WI
Altitude	msl bound lower : 31000 msl bound upper : 31000
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zau artcc : zmp artcc : zid
Operator	common carrier : air carrier
Make Model Name	Large Transport, Low Wing, 3 Turbojet Eng
Flight Phase	cruise other
Route In Use	enroute : on vectors enroute airway : zmp
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Experience	controller military : 4 controller non radar : 5 controller radar : 4
ASRS Report	115106
Person 2
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Events
Anomaly	conflict : airborne less severe non adherence : published procedure non adherence : required legal separation
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance other
Consequence	faa : investigated
Miss Distance	horizontal : 24600 vertical : 0
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error Inter Facility Coordination Failure

Narrative:

Aircraft were deviating around WX. An adjacent facility called with a manual handoff an air carrier X large transport at FL310. I had no flight plan information on this aircraft. The transferring controller coordinated a north heading. I took radar contact. The aircraft called and I acknowledged and then turned to other traffic attempting to call. About 45 second later I issued a 20 degree left turn to the other involved aircraft to an assigned heading of 320 degree. I then noticed the first aircraft on a west heading and issued turns to both aircraft in an attempt to maintain lateral separation. Closest proximity was same altitude, 4.1 miles lateral. The aircraft turned to a west heading because the previous controller had cleared the aircraft to join an east/west jet route and failed to coordinate that information with me at the time of handoff.

Original NASA ASRS Text

Title: 2 ACFT AT SAME ALT WITH LESS THAN STANDARD SEPARATION. SYSTEM ERROR.

Narrative: ACFT WERE DEVIATING AROUND WX. AN ADJACENT FAC CALLED WITH A MANUAL HANDOFF AN ACR X LGT AT FL310. I HAD NO FLT PLAN INFO ON THIS ACFT. THE TRANSFERRING CTLR COORDINATED A NORTH HDG. I TOOK RADAR CONTACT. THE ACFT CALLED AND I ACKNOWLEDGED AND THEN TURNED TO OTHER TFC ATTEMPTING TO CALL. ABOUT 45 SECOND LATER I ISSUED A 20 DEG LEFT TURN TO THE OTHER INVOLVED ACFT TO AN ASSIGNED HDG OF 320 DEG. I THEN NOTICED THE FIRST ACFT ON A WEST HDG AND ISSUED TURNS TO BOTH ACFT IN AN ATTEMPT TO MAINTAIN LATERAL SEPARATION. CLOSEST PROX WAS SAME ALT, 4.1 MILES LATERAL. THE ACFT TURNED TO A WEST HDG BECAUSE THE PREVIOUS CTLR HAD CLRED THE ACFT TO JOIN AN EAST/WEST JET ROUTE AND FAILED TO COORDINATE THAT INFO WITH ME AT THE TIME OF HANDOFF.

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.