Commuter given crossing restr, then issued traffic at altitude through which they would pass.

Attributes
ACN	314110
Time
Date	199508
Day	Wed
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : bae
State Reference	WI
Altitude	msl bound lower : 8000 msl bound upper : 10000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zau
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 135
Flight Phase	descent other
Route In Use	enroute other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : cfi pilot : instrument pilot : commercial pilot : atp
Experience	flight time last 90 days : 220 flight time total : 7500 flight time type : 5800
ASRS Report	314110
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	conflict : airborne less severe non adherence : required legal separation
Independent Detector	other controllera other flight crewa
Resolutory Action	controller : issued new clearance flight crew : took evasive action
Consequence	Other
Miss Distance	horizontal : 9000 vertical : 300
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

Flight from azo to mke. ATC (ZAU) issued us the crossing restr of 50 NM southeast of bae VOR at 8000 ft. While descending through 9400 ft MSL, chicago asked us to 'verify level at 10000 ft.' we re-idented our crossing restr to chicago, at which time the controller issued 9000 ft traffic at 3 mi moving southeast. Initially we had no contact on the traffic, and immediately climbed to 9500 ft, at which time we visually idented the aircraft. After acknowledging the target to ZAU the controller asked us to maintain visual separation from the aircraft, and maintain 8000 ft. At this time, my first officer and I are not quite sure how this problem arose, but we are confident the error was the issuance of an incorrect crossing altitude restr.

Original NASA ASRS Text

Title: COMMUTER GIVEN XING RESTR, THEN ISSUED TFC AT ALT THROUGH WHICH THEY WOULD PASS.

Narrative: FLT FROM AZO TO MKE. ATC (ZAU) ISSUED US THE XING RESTR OF 50 NM SE OF BAE VOR AT 8000 FT. WHILE DSNDING THROUGH 9400 FT MSL, CHICAGO ASKED US TO 'VERIFY LEVEL AT 10000 FT.' WE RE-IDENTED OUR XING RESTR TO CHICAGO, AT WHICH TIME THE CTLR ISSUED 9000 FT TFC AT 3 MI MOVING SE. INITIALLY WE HAD NO CONTACT ON THE TFC, AND IMMEDIATELY CLBED TO 9500 FT, AT WHICH TIME WE VISUALLY IDENTED THE ACFT. AFTER ACKNOWLEDGING THE TARGET TO ZAU THE CTLR ASKED US TO MAINTAIN VISUAL SEPARATION FROM THE ACFT, AND MAINTAIN 8000 FT. AT THIS TIME, MY FO AND I ARE NOT QUITE SURE HOW THIS PROB AROSE, BUT WE ARE CONFIDENT THE ERROR WAS THE ISSUANCE OF AN INCORRECT XING ALT RESTR.

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.