Narrative:

Air carrier X checked onto my frequency and I cleared the aircraft to deviate if necessary. The pilot responded by saying he was going to turn severely. I did not hear the pilot say that he was going to turn severely. The conflict alert activated and I turned air carrier X to a heading of 010 degrees immediately and then descended the aircraft to FL310. I lost standard separation with air carrier X and air carrier Y. I think it is extremely important for pilots to make it known to controllers if they are going to deviate severely. Supplemental information from acn 218301: I was working air carrier Y at FL330 nwbound in my airspace under normal operations. Conflict alert went off with an air carrier X (not in my airspace) that seemed to be converging with air carrier Y at the same altitude. I yelled down to the controller that I assumed was working the air carrier X to ask which way he was turning the aircraft. He told me air carrier X was turning right so I turned air carrier Y 15 degrees left and climbed to FL350. Supplemental information from acn 217829: air carrier X and air carrier Y were switched to 2 different controllers from the greencove/keystone sector at ZJX. Air carrier X turned over 90 degrees and flew directly at air carrier Y. Subsequent tape review showed that air carrier X requested a severe deviation to the left to avoid thunderstorms along its route. The controller who was working the aircraft approved the deviation without checking with the greencove/keystone sector (my sector). He was unaware of air carrier Y and he initiated control actions when the conflict alert went off.

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Original NASA ASRS Text

Title: ACR X UNCOORDINATED UNAUTH PENETRATION OF ADJOINING SECTOR AIRSPACE HAD LTSS FROM ACR Y. SYS ERROR.

Narrative: ACR X CHKED ONTO MY FREQ AND I CLRED THE ACFT TO DEVIATE IF NECESSARY. THE PLT RESPONDED BY SAYING HE WAS GOING TO TURN SEVERELY. I DID NOT HEAR THE PLT SAY THAT HE WAS GOING TO TURN SEVERELY. THE CONFLICT ALERT ACTIVATED AND I TURNED ACR X TO A HDG OF 010 DEGS IMMEDIATELY AND THEN DSNDED THE ACFT TO FL310. I LOST STANDARD SEPARATION WITH ACR X AND ACR Y. I THINK IT IS EXTREMELY IMPORTANT FOR PLTS TO MAKE IT KNOWN TO CTLRS IF THEY ARE GOING TO DEVIATE SEVERELY. SUPPLEMENTAL INFO FROM ACN 218301: I WAS WORKING ACR Y AT FL330 NWBOUND IN MY AIRSPACE UNDER NORMAL OPS. CONFLICT ALERT WENT OFF WITH AN ACR X (NOT IN MY AIRSPACE) THAT SEEMED TO BE CONVERGING WITH ACR Y AT THE SAME ALT. I YELLED DOWN TO THE CTLR THAT I ASSUMED WAS WORKING THE ACR X TO ASK WHICH WAY HE WAS TURNING THE ACFT. HE TOLD ME ACR X WAS TURNING R SO I TURNED ACR Y 15 DEGS L AND CLBED TO FL350. SUPPLEMENTAL INFO FROM ACN 217829: ACR X AND ACR Y WERE SWITCHED TO 2 DIFFERENT CTLRS FROM THE GREENCOVE/KEYSTONE SECTOR AT ZJX. ACR X TURNED OVER 90 DEGS AND FLEW DIRECTLY AT ACR Y. SUBSEQUENT TAPE REVIEW SHOWED THAT ACR X REQUESTED A SEVERE DEV TO THE L TO AVOID TSTMS ALONG ITS RTE. THE CTLR WHO WAS WORKING THE ACFT APPROVED THE DEV WITHOUT CHKING WITH THE GREENCOVE/KEYSTONE SECTOR (MY SECTOR). HE WAS UNAWARE OF ACR Y AND HE INITIATED CTL ACTIONS WHEN THE CONFLICT ALERT WENT OFF.

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.