Narrative:

Aircraft #1 was cleared after sby direct tyi direct dunkn. The pilot read back direct tay direct dunkn. I corrected the pilot and he read back the correct clearance. Near sby, the pilot questioned his clearance and I again cleared him direct tar river tyi. He read back tyi. Shortly after, I noticed the aircraft heading southeast when he should have been heading southwest. I cleared him to a 250 degree heading to avoid converging traffic. I then cleared aircraft #2 to a 910 degree heading. Aircraft #2 questioned the heading which I reissued and he read back. I saw that separation was not going to be maintained, so I descended aircraft #1 to FL280. He began a descent and aircraft #2 said he had an RA from TCASII to climb. I called traffic to aircraft #2 at 12 O'clock position, 5 mi nebound FL330 and traffic 10 O'clock position, 3 mi sebound descending, which was the aircraft the RA was for. Aircraft #2 never climbed. I then reclred both aircraft on course. After reviewing the tape, we tried to figure out what the pilot may have dialed in to put the aircraft on the southeast heading, but couldn't come up with anything.

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Original NASA ASRS Text

Title: ZDC CTLR OBSERVES B737 RERTE TRACK DEV CONFLICTING WITH OTHER TFC, BUT CTL ACTIONS AND PLT'S QUESTIONS RESULT IN A LOSS OF SEPARATION AND TCASII MANEUVER.

Narrative: ACFT #1 WAS CLRED AFTER SBY DIRECT TYI DIRECT DUNKN. THE PLT READ BACK DIRECT TAY DIRECT DUNKN. I CORRECTED THE PLT AND HE READ BACK THE CORRECT CLRNC. NEAR SBY, THE PLT QUESTIONED HIS CLRNC AND I AGAIN CLRED HIM DIRECT TAR RIVER TYI. HE READ BACK TYI. SHORTLY AFTER, I NOTICED THE ACFT HDG SE WHEN HE SHOULD HAVE BEEN HDG SW. I CLRED HIM TO A 250 DEG HDG TO AVOID CONVERGING TFC. I THEN CLRED ACFT #2 TO A 910 DEG HDG. ACFT #2 QUESTIONED THE HDG WHICH I REISSUED AND HE READ BACK. I SAW THAT SEPARATION WAS NOT GOING TO BE MAINTAINED, SO I DSNDED ACFT #1 TO FL280. HE BEGAN A DSCNT AND ACFT #2 SAID HE HAD AN RA FROM TCASII TO CLB. I CALLED TFC TO ACFT #2 AT 12 O'CLOCK POS, 5 MI NEBOUND FL330 AND TFC 10 O'CLOCK POS, 3 MI SEBOUND DSNDING, WHICH WAS THE ACFT THE RA WAS FOR. ACFT #2 NEVER CLBED. I THEN RECLRED BOTH ACFT ON COURSE. AFTER REVIEWING THE TAPE, WE TRIED TO FIGURE OUT WHAT THE PLT MAY HAVE DIALED IN TO PUT THE ACFT ON THE SE HDG, BUT COULDN'T COME UP WITH ANYTHING.

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.