ARTCC radar controller climbed an air carrier DC9 to wrong altitude for direction of flight to assist in avoiding turbulence, then realized he had traffic at that altitude, an air carrier B767, and descended the DC9 back to FL290, but not before TCASII alerted the DC9 and separation was already lost.

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Attributes
ACN	388020
Time
Date	199712
Day	Tue
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : jot
State Reference	IL
Altitude	msl bound lower : 29700 msl bound upper : 31000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zau
Operator	common carrier : air carrier
Make Model Name	Military Transport
Operating Under FAR Part	Part 121
Flight Phase	climbout : intermediate altitude cruise other
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Widebody, Low Wing, 2 Turbojet Eng
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : atp pilot : instrument
Experience	flight time last 90 days : 150 flight time total : 8500 flight time type : 4400
ASRS Report	388020
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	conflict : airborne less severe non adherence : required legal separation
Independent Detector	aircraft equipment other aircraft equipment : unspecified other controllera
Resolutory Action	controller : issued new clearance other
Consequence	Other
Miss Distance	horizontal : 6000 vertical : 1300
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

After departure from msp to ind we were level at FL290. We were advised that this would be our final altitude. Later we encountered light turbulence. We requested FL310 which we hoped would get us out of turbulence. ATC advised that when some traffic passed he would give it to us. After the traffic passed and a few mins later, ATC cleared us to FL310. I reported leaving FL290 for FL310 upon receipt of clearance. Climbing through FL297 our TCASII gave us a traffic alert. It registered 1300 ft above and 4 mi to our left. While slowly reducing rate of climb and looking for the aircraft ATC called and told us to descend back to FL290. We complied. The controller apologized many times for the incident. When we saw the aircraft go overhead, we were at FL294 I believe. After this traffic cleared, we were given, once again clearance back to FL310. Had TCASII not been on the aircraft and had the controller not noticed the conflict, this situation could have been worse. I believe this was an honest mistake. I also do not know how many other frequencys the controller was working. It was difficult to see the other aircraft since we were climbing into the sun at the time and he was at our 11 O'clock position.

Original NASA ASRS Text

Title: ARTCC RADAR CTLR CLBED AN ACR DC9 TO WRONG ALT FOR DIRECTION OF FLT TO ASSIST IN AVOIDING TURB, THEN REALIZED HE HAD TFC AT THAT ALT, AN ACR B767, AND DSNDED THE DC9 BACK TO FL290, BUT NOT BEFORE TCASII ALERTED THE DC9 AND SEPARATION WAS ALREADY LOST.

Narrative: AFTER DEP FROM MSP TO IND WE WERE LEVEL AT FL290. WE WERE ADVISED THAT THIS WOULD BE OUR FINAL ALT. LATER WE ENCOUNTERED LIGHT TURB. WE REQUESTED FL310 WHICH WE HOPED WOULD GET US OUT OF TURB. ATC ADVISED THAT WHEN SOME TFC PASSED HE WOULD GIVE IT TO US. AFTER THE TFC PASSED AND A FEW MINS LATER, ATC CLRED US TO FL310. I RPTED LEAVING FL290 FOR FL310 UPON RECEIPT OF CLRNC. CLBING THROUGH FL297 OUR TCASII GAVE US A TFC ALERT. IT REGISTERED 1300 FT ABOVE AND 4 MI TO OUR L. WHILE SLOWLY REDUCING RATE OF CLB AND LOOKING FOR THE ACFT ATC CALLED AND TOLD US TO DSND BACK TO FL290. WE COMPLIED. THE CTLR APOLOGIZED MANY TIMES FOR THE INCIDENT. WHEN WE SAW THE ACFT GO OVERHEAD, WE WERE AT FL294 I BELIEVE. AFTER THIS TFC CLRED, WE WERE GIVEN, ONCE AGAIN CLRNC BACK TO FL310. HAD TCASII NOT BEEN ON THE ACFT AND HAD THE CTLR NOT NOTICED THE CONFLICT, THIS SIT COULD HAVE BEEN WORSE. I BELIEVE THIS WAS AN HONEST MISTAKE. I ALSO DO NOT KNOW HOW MANY OTHER FREQS THE CTLR WAS WORKING. IT WAS DIFFICULT TO SEE THE OTHER ACFT SINCE WE WERE CLBING INTO THE SUN AT THE TIME AND HE WAS AT OUR 11 O'CLOCK POS.

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.