Less than standard separation occurred between 2 aircraft that were deviating around WX.

Attributes
ACN	149213
Time
Date	199006
Day	Fri
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : mzv
State Reference	IL
Altitude	msl bound lower : 19000 msl bound upper : 19000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zau
Operator	general aviation : corporate
Make Model Name	Medium Transport, Low Wing, 2 Turbojet Eng
Flight Phase	cruise other
Route In Use	enroute : on vectors
Flight Plan	IFR
Aircraft 2
Operator	general aviation : corporate
Make Model Name	Medium Transport, Low Wing, 2 Turbojet Eng
Flight Phase	cruise other
Route In Use	enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Experience	controller non radar : 17 controller radar : 17
ASRS Report	149213
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 non adherence : published procedure
Independent Detector	atc equipment other atc equipment : unspecified
Resolutory Action	controller : issued new clearance
Consequence	Other
Miss Distance	horizontal : 18000 vertical : 500
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

Mdt X departed alo-mli at FL190. Mdt Y departed cid-jot-east coast requesting FL330. Mdt Y deviating south around WX. Mdt X on an assigned heading of 180 degrees behind mdt Y. Mdt Y ended up north of projected route. Mdt X did not fly a 180 degree heading. They were assigned rtes that gave them sep, from which both deviated. While working other aircraft that were also in potential conflict, the 2 aircraft got together real quick. C/a did not go off until aircraft were already in conflict. Corrective action would have been many possible actions. Most obvious would have aircraft fly assigned route and not deviate. Also previous controller from adjacent sector should have had aircraft alo-mli descending to an appropriate altitude to land at airport which is just 20 mi away. Point of confliction was less than 10 mi from airport and aircraft were still at FL190. I was unable to give aircraft lower because of other traffic.

Original NASA ASRS Text

Title: LESS THAN STANDARD SEPARATION OCCURRED BETWEEN 2 ACFT THAT WERE DEVIATING AROUND WX.

Narrative: MDT X DEPARTED ALO-MLI AT FL190. MDT Y DEPARTED CID-JOT-E COAST REQUESTING FL330. MDT Y DEVIATING S AROUND WX. MDT X ON AN ASSIGNED HDG OF 180 DEGS BEHIND MDT Y. MDT Y ENDED UP N OF PROJECTED RTE. MDT X DID NOT FLY A 180 DEG HDG. THEY WERE ASSIGNED RTES THAT GAVE THEM SEP, FROM WHICH BOTH DEVIATED. WHILE WORKING OTHER ACFT THAT WERE ALSO IN POTENTIAL CONFLICT, THE 2 ACFT GOT TOGETHER REAL QUICK. C/A DID NOT GO OFF UNTIL ACFT WERE ALREADY IN CONFLICT. CORRECTIVE ACTION WOULD HAVE BEEN MANY POSSIBLE ACTIONS. MOST OBVIOUS WOULD HAVE ACFT FLY ASSIGNED RTE AND NOT DEVIATE. ALSO PREVIOUS CTLR FROM ADJACENT SECTOR SHOULD HAVE HAD ACFT ALO-MLI DSNDING TO AN APPROPRIATE ALT TO LAND AT ARPT WHICH IS JUST 20 MI AWAY. POINT OF CONFLICTION WAS LESS THAN 10 MI FROM ARPT AND ACFT WERE STILL AT FL190. I WAS UNABLE TO GIVE ACFT LOWER BECAUSE OF OTHER TFC.

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.