ZAU controller misses readback of climbing A320 which conflicts with an en route B190.

Attributes
ACN	513554
Time
Date	200105
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : ord.airport
Altitude	msl single value : 16000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zau.artcc tower : dfw.tower
Operator	common carrier : air carrier
Make Model Name	A320
Operating Under FAR Part	Part 121
Navigation In Use	other
Flight Phase	cruise : enroute altitude change cruise : level
Flight Plan	IFR
Aircraft 2
Controlling Facilities	artcc : zau.artcc
Operator	common carrier : air taxi
Make Model Name	Beech 1900
Operating Under FAR Part	Part 135
Flight Phase	climbout : vacating altitude climbout : intermediate altitude
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Experience	controller limited radar : 2 controller radar : 10 controller time certified in position1 : 10
ASRS Report	513554
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Events
Anomaly	conflict : airborne less severe non adherence : required legal separation non adherence : published procedure
Independent Detector	atc equipment : conflict alert other controllera
Resolutory Action	none taken : detected after the fact
Consequence	faa : investigated
Miss Distance	horizontal : 20800 vertical : 300
Supplementary
Problem Areas	ATC Human Performance
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

After assuming the sector, I issued traffic to aircraft X that was climbing off ord and advised I would have higher when he cleared the takeoff. Aircraft X's response was mumbled, but I perceived it to be an acknowledgement. After the targets passed, I noticed aircraft X was climbing above the altitude I thought he was cleared to. I was concerned because the 2 aircraft were not yet separated by the required 5 mi, but I didn't feel any urgency because our radar sometimes shows inaccurate altitude readouts (within 100-200 ft) and the targets had already passed one another. Additionally, at this point there was no action I could have taken to prevent the error.

Original NASA ASRS Text

Title: ZAU CTLR MISSES READBACK OF CLBING A320 WHICH CONFLICTS WITH AN ENRTE B190.

Narrative: AFTER ASSUMING THE SECTOR, I ISSUED TFC TO ACFT X THAT WAS CLBING OFF ORD AND ADVISED I WOULD HAVE HIGHER WHEN HE CLRED THE TKOF. ACFT X'S RESPONSE WAS MUMBLED, BUT I PERCEIVED IT TO BE AN ACKNOWLEDGEMENT. AFTER THE TARGETS PASSED, I NOTICED ACFT X WAS CLBING ABOVE THE ALT I THOUGHT HE WAS CLRED TO. I WAS CONCERNED BECAUSE THE 2 ACFT WERE NOT YET SEPARATED BY THE REQUIRED 5 MI, BUT I DIDN'T FEEL ANY URGENCY BECAUSE OUR RADAR SOMETIMES SHOWS INACCURATE ALT READOUTS (WITHIN 100-200 FT) AND THE TARGETS HAD ALREADY PASSED ONE ANOTHER. ADDITIONALLY, AT THIS POINT THERE WAS NO ACTION I COULD HAVE TAKEN TO PREVENT THE ERROR.

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.