ZAU controller described a loss of separation event when coordination with an adjacent sector was fl...

Attributes
ACN	942390
Time
Date	201104
Local Time Of Day	1201-1800
Place
Locale Reference	ZAU.ARTCC
State Reference	IL
Aircraft 1
Make Model Name	EMB ERJ 145 ER&LR
Operating Under FAR Part	Part 121
Flight Phase	Climb
Route In Use	Vectors
Flight Plan	IFR
Aircraft 2
Make Model Name	B757-200
Operating Under FAR Part	Part 121
Flight Phase	Descent
Flight Plan	IFR
Person 1
Qualification	Air Traffic Control Fully Certified
Person 2
Function	Handoff / Assist
Qualification	Air Traffic Control Fully Certified
Events
Anomaly	ATC Issue All Types Airspace Violation All Types Conflict Airborne Conflict Deviation - Procedural Published Material / Policy

Narrative:

An E145 was climbing to FL230 on vector of 240 degrees. The aircraft was pointed out to sector 74 and issued direct uin. When leaving FL220 I noticed a limited data block opposite direction descending through FL237. I issued traffic to the E145 and stopped his climb at FL220. At the same time the conflict alert went off. The E145 reported responding to the RA. Targets merged but no valid mode C was readable from the B757. Once clear of traffic; I re-cleared the E145 to FL230. I notified the supervisor of the possible operational error. The point out was made properly by our sector. The other controller must have dropped the data block at some point. Once the RA began; I did not issue any control instructions.

Original NASA ASRS Text

Title: ZAU Controller described a loss of separation event when coordination with an adjacent sector was flawed and complete Data Block absent.

Narrative: An E145 was climbing to FL230 on vector of 240 degrees. The aircraft was pointed out to Sector 74 and issued direct UIN. When leaving FL220 I noticed a limited data block opposite direction descending through FL237. I issued traffic to the E145 and stopped his climb at FL220. At the same time the Conflict Alert went off. The E145 reported responding to the RA. Targets merged but no valid Mode C was readable from the B757. Once clear of traffic; I re-cleared the E145 to FL230. I notified the Supervisor of the possible operational error. The point out was made properly by our sector. The other Controller must have dropped the data block at some point. Once the RA began; I did not issue any control instructions.

Data retrieved from NASA's ASRS site as of April 2012 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.

ZAU controller described a loss of separation event when coordination with an adjacent sector was flawed and complete data block absent.