Narrative:

An E50P called up for a pop up IFR clearance off of lxt airport. I told the aircraft to squawk the appropriate code and to maintain VFR. I radar identified the E50P and told them to maintain 3;000 ft and fly heading 360. I then pointed traffic out to the E50P that was 8 miles northwest of his position at 4;000 ft converging and gave the E50P his clearance climbing to 5;000 ft. The E50P acknowledged the clearance and climbing instructions. I cleaned up some other traffic and told a commander to descend to 3;000 ft so the E50P could climb above easier. I then continued to work because I was pretty busy with other traffic. The controller in charge at the time made me aware of the converging traffic and I turned the E50P to a 270 heading and again climbed to 5;000 ft because he was still indicating 3;000 ft. I had a brief conversation with the E50P because he was worried how to spell jthro in the clearance and again I told him to fly 270 and maintain 5;000 ft. Then I gave the commander a turn heading 360 to ensure they would not converge. It took the the E50P one minute and 10 seconds to climb out of 3;000 ft and once I had the convergence with the two aircraft; I turned them both back on course and continued to work traffic. The traffic got within 2.55 miles and 200 ft from each other. I would watch the situation better next time and make sure the E50P actually climbs. I would also turn the E50P to the northwest away from the commander so they both would be no factor for each other. I could have also kept the E50P at 3;000 ft until the traffic passed and then climb.

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Original NASA ASRS Text

Title: MCI Controller and Supervisor described a loss of separation event when a pop-up VFR aircraft; confused with the clearance issued; failed to climb as expected.

Narrative: An E50P called up for a pop up IFR clearance off of LXT airport. I told the aircraft to squawk the appropriate code and to maintain VFR. I radar identified the E50P and told them to maintain 3;000 FT and fly heading 360. I then pointed traffic out to the E50P that was 8 miles northwest of his position at 4;000 FT converging and gave the E50P his clearance climbing to 5;000 FT. The E50P acknowledged the clearance and climbing instructions. I cleaned up some other traffic and told a Commander to descend to 3;000 FT so the E50P could climb above easier. I then continued to work because I was pretty busy with other traffic. The CIC at the time made me aware of the converging traffic and I turned the E50P to a 270 heading and again climbed to 5;000 FT because he was still indicating 3;000 FT. I had a brief conversation with the E50P because he was worried how to spell JTHRO in the clearance and again I told him to fly 270 and maintain 5;000 FT. Then I gave the Commander a turn heading 360 to ensure they would not converge. It took the the E50P one minute and 10 seconds to climb out of 3;000 FT and once I had the convergence with the two aircraft; I turned them both back on course and continued to work traffic. The traffic got within 2.55 miles and 200 FT from each other. I would watch the situation better next time and make sure the E50P actually climbs. I would also turn the E50P to the northwest away from the Commander so they both would be no factor for each other. I could have also kept the E50P at 3;000 FT until the traffic passed and then climb.

Data retrieved from NASA's ASRS site as of April 2012 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.