Narrative:

These two aircraft were alerted in my uret to be a factor with one another. I had track control and communication with aircraft X level flight at FL360 feet. Aircraft Y was climbing from ZLA center to FL390 feet. I pulled the aircraft up on my scope prior to ZLA handing off the aircraft. I was going to call and issue a control instruction for them to stop aircraft Y at FL350 feet for traffic. However; before I did that the controller on the sector had entered an interim altitude in the data tag of FL350 on aircraft Y on his own. At this point the ZLA controller was already talking to aircraft X. There was no need for me to call and stop the aircraft's climb because they had seen the traffic. ZLA then hands aircraft X off to me with FL350 in data tag as an interim altitude and FL390 as a final requested altitude. Aircraft X checks on with me climbing to FL390 feet (which I didn't hear until listening to the tapes after the fact). I thought he checked on climbing to FL350 feet. I issued traffic to aircraft Y 'traffic 11 o'clock 10 miles aircraft X heavy at FL360' the aircraft Y responds and says 'rodger; looking' or something to that effect. A couple hits later I see the aircraft Y at FL353 feet; I verify with him that he is level at 35000 feet. He responds 'negative we are climbing to FL390'. I this point I realized ZLA's error and potentially my own in having missed a check on altitude. After getting off position and listening to the tapes I realized the aircraft did check on climbing to FL390 feet. The ZLA controller loaded up FL350 in the data block and never stopped the aircraft's climb. I missed a check on and the pilot failed to acknowledge a traffic call and how it might affect him.

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Original NASA ASRS Text

Title: A Center Controller reported a handoff of an aircraft whose radar data indicated it was climbing to 35;000 feet. The aircraft was climbing to 39;000 feet; and conflicting with traffic at 36;000 feet.

Narrative: These two aircraft were alerted in my URET to be a factor with one another. I had track control and communication with Aircraft X level flight at FL360 feet. Aircraft Y was climbing from ZLA center to FL390 feet. I pulled the aircraft up on my scope prior to ZLA handing off the aircraft. I was going to call and issue a control instruction for them to stop Aircraft Y at FL350 feet for traffic. However; before I did that the controller on the sector had entered an interim altitude in the data tag of FL350 on Aircraft Y on his own. At this point the ZLA controller was already talking to Aircraft X. There was no need for me to call and stop the aircraft's climb because they had seen the traffic. ZLA then hands Aircraft X off to me with FL350 in data tag as an interim altitude and FL390 as a final requested altitude. Aircraft X checks on with me climbing to FL390 feet (which I didn't hear until listening to the tapes after the fact). I thought he checked on climbing to FL350 feet. I issued traffic to Aircraft Y 'traffic 11 o'clock 10 miles Aircraft X Heavy at FL360' the Aircraft Y responds and says 'rodger; looking' or something to that effect. A couple hits later I see the Aircraft Y at FL353 feet; I verify with him that he is level at 35000 feet. He responds 'negative we are climbing to FL390'. I this point I realized ZLA's error and potentially my own in having missed a check on altitude. After getting off position and listening to the tapes I realized the aircraft did check on climbing to FL390 feet. The ZLA controller loaded up FL350 in the data block and never stopped the aircraft's climb. I missed a check on and the pilot failed to acknowledge a traffic call and how it might affect him.

Data retrieved from NASA's ASRS site 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.