Narrative:

A slower aircraft in front. I turned the jet out to the west for a descent. Once path was clear of the smaller aircraft, I descended him, then went back and told him, 'leaving FL230, cleared direct ATR.' I then went back to pilot (not knowing that I missed the readback) and put him on a parallel heading. The pilot had 1 min, 40 seconds to turn to this heading. Once I noticed the target heading straight for the slower aircraft, I asked the airliner if he was on the assigned heading. He responded with 'were turning to it now,' which of course was way too late and he was inside of the 5 mi 'J' ring. I believe if I had never missed the original mis-readback that this would have never occurred. I also had to tell the pilot 4 times to fly a heading. If the pilots were more aware of ATC controllers talking to them, I believe that he would have been on a parallel heading in plenty of time. This pilot had to have all clrncs read to him at least 2 times, and sometimes up to 4 times. No other pilots on my frequency at the time had any trouble hearing me. Just appeared that he was not listening up.

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Original NASA ASRS Text

Title: ZDC CTLR ISSUES CLRNC TO SEPARATE A BE20 AND A B733, BUT MISSES READBACKS AND HAS INCONSISTENT COMPLIANCE BY B733 FLC.

Narrative: A SLOWER ACFT IN FRONT. I TURNED THE JET OUT TO THE W FOR A DSCNT. ONCE PATH WAS CLR OF THE SMALLER ACFT, I DSNDED HIM, THEN WENT BACK AND TOLD HIM, 'LEAVING FL230, CLRED DIRECT ATR.' I THEN WENT BACK TO PLT (NOT KNOWING THAT I MISSED THE READBACK) AND PUT HIM ON A PARALLEL HDG. THE PLT HAD 1 MIN, 40 SECONDS TO TURN TO THIS HDG. ONCE I NOTICED THE TARGET HDG STRAIGHT FOR THE SLOWER ACFT, I ASKED THE AIRLINER IF HE WAS ON THE ASSIGNED HDG. HE RESPONDED WITH 'WERE TURNING TO IT NOW,' WHICH OF COURSE WAS WAY TOO LATE AND HE WAS INSIDE OF THE 5 MI 'J' RING. I BELIEVE IF I HAD NEVER MISSED THE ORIGINAL MIS-READBACK THAT THIS WOULD HAVE NEVER OCCURRED. I ALSO HAD TO TELL THE PLT 4 TIMES TO FLY A HDG. IF THE PLTS WERE MORE AWARE OF ATC CTLRS TALKING TO THEM, I BELIEVE THAT HE WOULD HAVE BEEN ON A PARALLEL HDG IN PLENTY OF TIME. THIS PLT HAD TO HAVE ALL CLRNCS READ TO HIM AT LEAST 2 TIMES, AND SOMETIMES UP TO 4 TIMES. NO OTHER PLTS ON MY FREQ AT THE TIME HAD ANY TROUBLE HEARING ME. JUST APPEARED THAT HE WAS NOT LISTENING UP.

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.