ZID controller watches conflict developing between a descending carj and a level, en route B737.

Attributes
ACN	586829
Time
Date	200307
Day	Wed
Local Time Of Day	1801 To 2400
Place
Locale Reference	navaid : hvq.vortac
State Reference	WV
Altitude	msl bound lower : 31000 msl bound upper : 33000
Environment
Flight Conditions	IMC
Weather Elements	Turbulence
Light	Night
Aircraft 1
Controlling Facilities	artcc : zid.artcc tower : lga.tower
Operator	common carrier : air carrier
Make Model Name	Regional Jet 200 ER&LR
Operating Under FAR Part	Part 121
Flight Phase	descent : intermediate altitude
Route In Use	enroute airway : j6.airway
Flight Plan	IFR
Aircraft 2
Controlling Facilities	artcc : zid.artcc
Operator	common carrier : air carrier
Make Model Name	B737-700
Operating Under FAR Part	Part 121
Flight Phase	cruise : level
Route In Use	enroute airway : j6.airway
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Experience	controller radar : 8 flight time total : 200
ASRS Report	586829
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Events
Anomaly	conflict : airborne less severe non adherence : required legal separation
Independent Detector	atc equipment : conflict alert other controllera
Resolutory Action	controller : issued new clearance
Miss Distance	horizontal : 27000 vertical : 300
Supplementary
Problem Areas	ATC Human Performance
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

B737 at FL310, wbound on taxiway J6. CRJ2 at FL350, wbound on taxiway J6, about 6.5 mile in trail. They were the same speed. Winds at the 2 altitudes were the same. CRJ2 destination is sdf, which SOP says needs to enter the next sector at FL280. I issued a descent to CRJ2 and continued to watch the speeds. They remained the same through FL330. Traffic was increasing, so I took care of some other things and came back. I noticed CRJ2 had accelerated to 470 KTS from 445 KTS ground speed. I thought maybe it was a bad radar return, so I watched 2 more updates. Ground speed increased further to 485 KTS. Even though CRJ2 was slightly north of B737 track, I was forced to turn CRJ2 30 degrees left across B737's tail, due to conflicting FL330 aircraft eastbound. I issued 30 degrees right to B737. CRJ2 continued to increase ground speed to 495 KTS, so I issued a 180 degree heading to CRJ2. I got no conflict alert until aedp went off. After getting the aircraft apart, I got them back on course.

Original NASA ASRS Text

Title: ZID CTLR WATCHES CONFLICT DEVELOPING BTWN A DSNDING CARJ AND A LEVEL, ENRTE B737.

Narrative: B737 AT FL310, WBOUND ON TXWY J6. CRJ2 AT FL350, WBOUND ON TXWY J6, ABOUT 6.5 MILE IN TRAIL. THEY WERE THE SAME SPD. WINDS AT THE 2 ALTS WERE THE SAME. CRJ2 DEST IS SDF, WHICH SOP SAYS NEEDS TO ENTER THE NEXT SECTOR AT FL280. I ISSUED A DSCNT TO CRJ2 AND CONTINUED TO WATCH THE SPDS. THEY REMAINED THE SAME THROUGH FL330. TFC WAS INCREASING, SO I TOOK CARE OF SOME OTHER THINGS AND CAME BACK. I NOTICED CRJ2 HAD ACCELERATED TO 470 KTS FROM 445 KTS GND SPD. I THOUGHT MAYBE IT WAS A BAD RADAR RETURN, SO I WATCHED 2 MORE UPDATES. GND SPD INCREASED FURTHER TO 485 KTS. EVEN THOUGH CRJ2 WAS SLIGHTLY N OF B737 TRACK, I WAS FORCED TO TURN CRJ2 30 DEGS L ACROSS B737'S TAIL, DUE TO CONFLICTING FL330 ACFT EBOUND. I ISSUED 30 DEGS R TO B737. CRJ2 CONTINUED TO INCREASE GND SPD TO 495 KTS, SO I ISSUED A 180 DEG HDG TO CRJ2. I GOT NO CONFLICT ALERT UNTIL AEDP WENT OFF. AFTER GETTING THE ACFT APART, I GOT THEM BACK ON COURSE.

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.