Narrative:

All aircraft were deviating south of J6, including numerous other aircraft in the sector. The J6 traffic were asked to be rerouted 45 mins before incident and were not. The MD80 was deviating south at FL280 and was handed off to the sector to the south. After leaving the sector, the data block was dropped from the scope. A few mins later the T/B712 was being handed off to me from the sector from the south. He was traffic with an aircraft in my sector coming from the west at FL290. My tracker position coordinated for the B712 to descend to FL280 with the south sector. After coordination the tracker told me to take the B712 to FL280. When the B712 was out of FL287 the conflict alert went off, and I climbed the B712 immediately back to FL290. Some things leading to the situation were the WX display on the radar scope, number data blocks in the same area, deviating aircraft, and frequency congestion due to WX and chop. The controller to the south did not reference the aircraft at FL280 because that aircraft came from us, and he was thinking we were still watching that aircraft, but due to the amount of data blocks and deviating aircraft we dropped the aircraft data block as soon as it left our sector. The limited data block was still there but unnoticed due to WX display and numerous other full and limited data blocks in the area. Supplemental information from acn 581948: this incident happened 12 seconds after the operational error in my other letter. The LJ55 was on J6 and wanted to deviate south. I descended the aircraft to FL280 and climbed him to deviate south and handed off to the sector to the south. A few mins later, after the LJ55 was out of my airspace, the south sector handed off the E145 to me at FL290. He was traffic with another aircraft in my sector coming from west at FL290. My tracker coordinated with the south sector to descend the E145 to FL280 along with the other aircraft mentioned in my other letter. After coordinating with the south sector, my tracker told me to descend both aircraft to FL280. The E145 was descended to FL280 and cleared to deviate 30 degrees right off course for WX. The conflict alert went off a couple mins later on the first 2 aircraft in my other letter. While giving evasive action to the other aircraft, the conflict alert went off on the E145 and the LJ55. The E145 was 500 ft above and 3 mi behind the LJ55. Seeing there was nothing I could do to alleviate that situation, I stopped the E145 deviation turn so he wouldn't be traffic with the MD80 mentioned in my other letter. The sits leading to this event were the same as the ones in my other letter. They were only 20 mi latterly from each other. The LJ55 was not referenced to me because the aircraft came from my sector, but being out of my sector and deviating south the data block was dropped from my scope by the tracker position. The LJ55 limited data block was unnoticed due to the new WX display and numerous other full and limited data blocks in the area, as well as the other sits referenced in my other letter to you.

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Original NASA ASRS Text

Title: ZID CTLR EXPERIENCED LOSS OF SEPARATION WITH SEVERAL ACFT DURING SAME INCIDENT.

Narrative: ALL ACFT WERE DEVIATING S OF J6, INCLUDING NUMEROUS OTHER ACFT IN THE SECTOR. THE J6 TFC WERE ASKED TO BE REROUTED 45 MINS BEFORE INCIDENT AND WERE NOT. THE MD80 WAS DEVIATING S AT FL280 AND WAS HANDED OFF TO THE SECTOR TO THE S. AFTER LEAVING THE SECTOR, THE DATA BLOCK WAS DROPPED FROM THE SCOPE. A FEW MINS LATER THE T/B712 WAS BEING HANDED OFF TO ME FROM THE SECTOR FROM THE S. HE WAS TFC WITH AN ACFT IN MY SECTOR COMING FROM THE W AT FL290. MY TRACKER POS COORDINATED FOR THE B712 TO DSND TO FL280 WITH THE S SECTOR. AFTER COORD THE TRACKER TOLD ME TO TAKE THE B712 TO FL280. WHEN THE B712 WAS OUT OF FL287 THE CONFLICT ALERT WENT OFF, AND I CLBED THE B712 IMMEDIATELY BACK TO FL290. SOME THINGS LEADING TO THE SIT WERE THE WX DISPLAY ON THE RADAR SCOPE, NUMBER DATA BLOCKS IN THE SAME AREA, DEVIATING ACFT, AND FREQ CONGESTION DUE TO WX AND CHOP. THE CTLR TO THE S DID NOT REF THE ACFT AT FL280 BECAUSE THAT ACFT CAME FROM US, AND HE WAS THINKING WE WERE STILL WATCHING THAT ACFT, BUT DUE TO THE AMOUNT OF DATA BLOCKS AND DEVIATING ACFT WE DROPPED THE ACFT DATA BLOCK AS SOON AS IT LEFT OUR SECTOR. THE LIMITED DATA BLOCK WAS STILL THERE BUT UNNOTICED DUE TO WX DISPLAY AND NUMEROUS OTHER FULL AND LIMITED DATA BLOCKS IN THE AREA. SUPPLEMENTAL INFO FROM ACN 581948: THIS INCIDENT HAPPENED 12 SECONDS AFTER THE OPERROR IN MY OTHER LETTER. THE LJ55 WAS ON J6 AND WANTED TO DEVIATE S. I DSNDED THE ACFT TO FL280 AND CLBED HIM TO DEVIATE S AND HANDED OFF TO THE SECTOR TO THE S. A FEW MINS LATER, AFTER THE LJ55 WAS OUT OF MY AIRSPACE, THE S SECTOR HANDED OFF THE E145 TO ME AT FL290. HE WAS TFC WITH ANOTHER ACFT IN MY SECTOR COMING FROM W AT FL290. MY TRACKER COORDINATED WITH THE S SECTOR TO DSND THE E145 TO FL280 ALONG WITH THE OTHER ACFT MENTIONED IN MY OTHER LETTER. AFTER COORDINATING WITH THE S SECTOR, MY TRACKER TOLD ME TO DSND BOTH ACFT TO FL280. THE E145 WAS DSNDED TO FL280 AND CLRED TO DEVIATE 30 DEGS R OFF COURSE FOR WX. THE CONFLICT ALERT WENT OFF A COUPLE MINS LATER ON THE FIRST 2 ACFT IN MY OTHER LETTER. WHILE GIVING EVASIVE ACTION TO THE OTHER ACFT, THE CONFLICT ALERT WENT OFF ON THE E145 AND THE LJ55. THE E145 WAS 500 FT ABOVE AND 3 MI BEHIND THE LJ55. SEEING THERE WAS NOTHING I COULD DO TO ALLEVIATE THAT SIT, I STOPPED THE E145 DEV TURN SO HE WOULDN'T BE TFC WITH THE MD80 MENTIONED IN MY OTHER LETTER. THE SITS LEADING TO THIS EVENT WERE THE SAME AS THE ONES IN MY OTHER LETTER. THEY WERE ONLY 20 MI LATTERLY FROM EACH OTHER. THE LJ55 WAS NOT REFED TO ME BECAUSE THE ACFT CAME FROM MY SECTOR, BUT BEING OUT OF MY SECTOR AND DEVIATING S THE DATA BLOCK WAS DROPPED FROM MY SCOPE BY THE TRACKER POS. THE LJ55 LIMITED DATA BLOCK WAS UNNOTICED DUE TO THE NEW WX DISPLAY AND NUMEROUS OTHER FULL AND LIMITED DATA BLOCKS IN THE AREA, AS WELL AS THE OTHER SITS REFED IN MY OTHER LETTER TO YOU.

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.