Air carrier Y same altitude assigned overtook air carrier X had less than standard separation. Syste...

Attributes
ACN	263084
Time
Date	199402
Day	Thu
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : ord
State Reference	IL
Altitude	msl bound lower : 4000 msl bound upper : 4000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : ord tower : ord
Operator	common carrier : air carrier
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	climbout : intermediate altitude cruise other
Route In Use	enroute : on vectors
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	climbout : intermediate altitude cruise other
Route In Use	enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : local
Qualification	controller : radar
ASRS Report	263084
Person 2
Affiliation	government : faa
Function	controller : departure
Qualification	controller : radar
Events
Anomaly	conflict : airborne less severe non adherence : required legal separation non adherence : published procedure
Independent Detector	other controllera
Resolutory Action	none taken : anomaly accepted
Consequence	Other
Miss Distance	horizontal : 12000 vertical : 0
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error Inter Facility Coordination Failure

Narrative:

I cleared air carrier X for takeoff on runway 32L with a turn to 070 degrees. When he was airborne and past the departure end of the runway, I cleared air carrier Y for takeoff to 070 degree heading. Both aircraft were ebounds. I told air carrier X to contact departure. When I was ready to ship air carrier Y to departure I did not want to turn him further east because of a light aircraft on a 090 degree heading. I knew air carrier Y was 'gaining ground' on air carrier X but due, to route relationship, I didn't want to turn air carrier Y left. I told air carrier Y to contact departure assuming the departure controller would turn air carrier Y and keep him above the light aircraft. However, the departure controller did not. Separation was less than 3 mi when I sent air carrier Y to departure control.

Original NASA ASRS Text

Title: ACR Y SAME ALT ASSIGNED OVERTOOK ACR X HAD LTSS. SYS ERROR.

Narrative: I CLRED ACR X FOR TKOF ON RWY 32L WITH A TURN TO 070 DEGS. WHEN HE WAS AIRBORNE AND PAST THE DEP END OF THE RWY, I CLRED ACR Y FOR TKOF TO 070 DEG HDG. BOTH ACFT WERE EBOUNDS. I TOLD ACR X TO CONTACT DEP. WHEN I WAS READY TO SHIP ACR Y TO DEP I DID NOT WANT TO TURN HIM FURTHER E BECAUSE OF A LIGHT ACFT ON A 090 DEG HDG. I KNEW ACR Y WAS 'GAINING GND' ON ACR X BUT DUE, TO RTE RELATIONSHIP, I DIDN'T WANT TO TURN ACR Y L. I TOLD ACR Y TO CONTACT DEP ASSUMING THE DEP CTLR WOULD TURN ACR Y AND KEEP HIM ABOVE THE LIGHT ACFT. HOWEVER, THE DEP CTLR DID NOT. SEPARATION WAS LESS THAN 3 MI WHEN I SENT ACR Y TO DEP CTL.

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.

Air carrier Y same altitude assigned overtook air carrier X had less than standard separation. System error.