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.
Synopsis
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.
Second reporter narrative
A Commander was inbound to LXT airport on a vector for approach by the satellite controller near ANX VOR level at 4;000 FT. A E50P departed LXT airport VFR looking for his IFR clearance. The clearance was issued to the E50P and he was initially given a vector to a 360 heading at 3;000 FT. The Satellite Controller then issued a climb to the E50P to 5;000 FT. In the very next transmission the Commander was issued a descent to 3;000 FT. The E50P never climbed; even though he read back 5;000 FT; and it was then that I walked over from my CIC position and told him to turn the aircraft because separation was in jeopardy. The Controller then turned the E50P to a 270 heading and reissued the climb to 5;000 FT; and again the pilot acknowledged the climb. The Commander was also turned to a 360 heading to further help the situation. Finally; the E50P climbed out of 3;000 FT; but the separation had already been lost. The pilot kept asking the Satellite Controller what the phonetic spelling was for JTHRO Intersection; rather than climb his airplane as instructed. Recommendation; I feel that the pilot of the E50P was the causative factor in this event. It took over 1 full minute for that aircraft to begin his climb. After watching and reviewing the RADAR data; in 1 minute the aircraft climbed 1;700 FT. If this climb had been started when instructed; there would have been nearly 2;000 FT between these aircraft and the whole event would never have happened. I also feel that the Controller took the appropriate steps to prevent any type of collision; and did what he could do to prevent the error.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.