Air carrier X possible less than standard separation from air carrier Y. Possible system error.

Attributes
ACN	245431
Time
Date	199307
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : ord
State Reference	IL
Altitude	msl bound lower : 4000 msl bound upper : 5300
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : ord
Operator	common carrier : air carrier
Make Model Name	Widebody, Low Wing, 4 Turbojet Eng
Navigation In Use	Other Other
Flight Phase	climbout : intermediate altitude
Route In Use	enroute : on vectors
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Widebody, Low Wing, 3 Turbojet Eng
Navigation In Use	Other
Flight Phase	descent other
Route In Use	enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : departure
Qualification	controller : radar
Experience	controller military : 5 controller radar : 12
ASRS Report	245431
Person 2
Affiliation	government : faa
Function	controller : approach
Qualification	controller : radar
Events
Anomaly	conflict : airborne less severe
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance other
Consequence	Other
Miss Distance	horizontal : 18000 vertical : 600
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	other

Narrative:

Air carrier X northbound over runway 22R final, air carrier X departed runway 14L. No traffic from southeast to prevent air carrier X from paralleling runway 22R final and climbing to get above the final. I asked for a good rate of climb and it appeared air carrier X was executing the instruction. We used prearranged coordination for our climbs at ord, so it is necessary to insure climbs in large gaps so vertical is not necessary. Air carrier X is out of 3400 ft and above the 'a' traffic so I turned him to 340 degrees and work other aircraft. Air carrier Y was 7 mi in trail. Approximately 30-40 seconds later I looked back and air carrier X had stopped climbing or climbing at a much slower rate and turning at a very slow rate. I immediately issued a 290 degree heading and asked again for his best rate because air carrier Y was now 4 1/2 mi away at 5300 ft. The other controller involved calls traffic and turns air carrier Y to 200 degree heading. However, air carrier Y reported air carrier X in sight and instructs air carrier Y to maintain visual separation but I do not remember if I told mine that visual separation was being applied because I was busy with the rest of my traffic. Subsequent visual separation allowed for 3 mi, 600 ft.

Original NASA ASRS Text

Title: ACR X POSSIBLE LTSS FROM ACR Y. POSSIBLE SYS ERROR.

Narrative: ACR X NBOUND OVER RWY 22R FINAL, ACR X DEPARTED RWY 14L. NO TFC FROM SE TO PREVENT ACR X FROM PARALLELING RWY 22R FINAL AND CLBING TO GET ABOVE THE FINAL. I ASKED FOR A GOOD RATE OF CLB AND IT APPEARED ACR X WAS EXECUTING THE INSTRUCTION. WE USED PREARRANGED COORD FOR OUR CLBS AT ORD, SO IT IS NECESSARY TO INSURE CLBS IN LARGE GAPS SO VERT IS NOT NECESSARY. ACR X IS OUT OF 3400 FT AND ABOVE THE 'A' TFC SO I TURNED HIM TO 340 DEGS AND WORK OTHER ACFT. ACR Y WAS 7 MI IN TRAIL. APPROX 30-40 SECONDS LATER I LOOKED BACK AND ACR X HAD STOPPED CLBING OR CLBING AT A MUCH SLOWER RATE AND TURNING AT A VERY SLOW RATE. I IMMEDIATELY ISSUED A 290 DEG HDG AND ASKED AGAIN FOR HIS BEST RATE BECAUSE ACR Y WAS NOW 4 1/2 MI AWAY AT 5300 FT. THE OTHER CTLR INVOLVED CALLS TFC AND TURNS ACR Y TO 200 DEG HDG. HOWEVER, ACR Y RPTED ACR X IN SIGHT AND INSTRUCTS ACR Y TO MAINTAIN VISUAL SEPARATION BUT I DO NOT REMEMBER IF I TOLD MINE THAT VISUAL SEPARATION WAS BEING APPLIED BECAUSE I WAS BUSY WITH THE REST OF MY TFC. SUBSEQUENT VISUAL SEPARATION ALLOWED FOR 3 MI, 600 FT.

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.