Narrative:

I had recently (5 mins prior) worked 35+ aircraft at any one time with a tracker for about 30 mins. After the traffic died down somewhat, the tracker went on break. Thunderstorms developing north of gck 30 mi with all aircraft deviating for them. Air carrier Y checked on frequency at FL270 begging for higher altitude. I climbed him to FL290, 'higher shortly.' after making certain there was no traffic for him, I then climbed him to FL330. Several mins later, air carrier X at FL310, requested deviation to 'about 280 degree heading.' I approved the deviation and believed he would miss air carrier Y. When the aircraft were 10-12 mi apart, I realized the air carrier X had turned more than the 280 degrees, so I instructed him to turn '50 degrees left immediately.' no response. Turned him 50 degrees left again, 3 seconds later, he answered several seconds after that. Loss of separation occurred but aircraft were never in jeopardy of scraping. Separation reestablished and I was relieved from position 10 mins or so later. Both aircraft were deviating at one point or other.

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Original NASA ASRS Text

Title: ZKC CTLR EXPERIENCED OPERROR AT FL310 DURING VECTORS AND WX DEV.

Narrative: I HAD RECENTLY (5 MINS PRIOR) WORKED 35+ ACFT AT ANY ONE TIME WITH A TRACKER FOR ABOUT 30 MINS. AFTER THE TFC DIED DOWN SOMEWHAT, THE TRACKER WENT ON BREAK. TSTMS DEVELOPING N OF GCK 30 MI WITH ALL ACFT DEVIATING FOR THEM. ACR Y CHKED ON FREQ AT FL270 BEGGING FOR HIGHER ALT. I CLBED HIM TO FL290, 'HIGHER SHORTLY.' AFTER MAKING CERTAIN THERE WAS NO TFC FOR HIM, I THEN CLBED HIM TO FL330. SEVERAL MINS LATER, ACR X AT FL310, REQUESTED DEVIATION TO 'ABOUT 280 DEG HDG.' I APPROVED THE DEV AND BELIEVED HE WOULD MISS ACR Y. WHEN THE ACFT WERE 10-12 MI APART, I REALIZED THE ACR X HAD TURNED MORE THAN THE 280 DEGS, SO I INSTRUCTED HIM TO TURN '50 DEGS L IMMEDIATELY.' NO RESPONSE. TURNED HIM 50 DEGS L AGAIN, 3 SECONDS LATER, HE ANSWERED SEVERAL SECONDS AFTER THAT. LOSS OF SEPARATION OCCURRED BUT ACFT WERE NEVER IN JEOPARDY OF SCRAPING. SEPARATION REESTABLISHED AND I WAS RELIEVED FROM POS 10 MINS OR SO LATER. BOTH ACFT WERE DEVIATING AT ONE POINT OR OTHER.

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.