Narrative:

I had assigned a 285 degree heading to air carrier X at FL350 to comply with the 30 mi in-trail restr to dulles (iad). I accepted a handoff on air carrier Y at FL370 proceeding direct albany (alb), landing manchester (mht). I cleared air carrier X direct sparta (sax) when the required in-trail spacing was achieved. Other iad traffic was being vectored to comply with the in-trail restr. The supervisor informed us that air carrier Z was exempt from the in-trail restr, but we were requested to give as many mi in-trail as possible. The d-side was very busy seeing where this aircraft would fit in with other iad traffic. The sector was very busy and I had other aircraft on vectors. The d-side was having difficulty contacting ZNY to coordinate parallel headings on 2 other aircraft. They wanted 1 aircraft assigned a different altitude and I complied with that. I then cleared air carrier Y to descend to FL330 to comply with the restr on aircraft landing mht. I recognized that air carrier Y's descent was going to be close to air carrier X. I assigned air carrier X a left turn, instructed air carrier Y to stop descending, and also assigned air carrier Y a left turn. A contributing factor was the 30 mi in-trail restr. This traffic must be taken off their route and vectored which can cause conflict with other aircraft. This increases greatly the workload.

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Original NASA ASRS Text

Title: ZBW CTLR EXPERIENCED OPERROR AT FL350 DURING VECTORS FOR IN-TRAIL SPACING REQUIREMENT.

Narrative: I HAD ASSIGNED A 285 DEG HDG TO ACR X AT FL350 TO COMPLY WITH THE 30 MI IN-TRAIL RESTR TO DULLES (IAD). I ACCEPTED A HDOF ON ACR Y AT FL370 PROCEEDING DIRECT ALBANY (ALB), LNDG MANCHESTER (MHT). I CLRED ACR X DIRECT SPARTA (SAX) WHEN THE REQUIRED IN-TRAIL SPACING WAS ACHIEVED. OTHER IAD TFC WAS BEING VECTORED TO COMPLY WITH THE IN-TRAIL RESTR. THE SUPVR INFORMED US THAT ACR Z WAS EXEMPT FROM THE IN-TRAIL RESTR, BUT WE WERE REQUESTED TO GIVE AS MANY MI IN-TRAIL AS POSSIBLE. THE D-SIDE WAS VERY BUSY SEEING WHERE THIS ACFT WOULD FIT IN WITH OTHER IAD TFC. THE SECTOR WAS VERY BUSY AND I HAD OTHER ACFT ON VECTORS. THE D-SIDE WAS HAVING DIFFICULTY CONTACTING ZNY TO COORDINATE PARALLEL HDGS ON 2 OTHER ACFT. THEY WANTED 1 ACFT ASSIGNED A DIFFERENT ALT AND I COMPLIED WITH THAT. I THEN CLRED ACR Y TO DSND TO FL330 TO COMPLY WITH THE RESTR ON ACFT LNDG MHT. I RECOGNIZED THAT ACR Y'S DSCNT WAS GOING TO BE CLOSE TO ACR X. I ASSIGNED ACR X A L TURN, INSTRUCTED ACR Y TO STOP DSNDING, AND ALSO ASSIGNED ACR Y A L TURN. A CONTRIBUTING FACTOR WAS THE 30 MI IN-TRAIL RESTR. THIS TFC MUST BE TAKEN OFF THEIR RTE AND VECTORED WHICH CAN CAUSE CONFLICT WITH OTHER ACFT. THIS INCREASES GREATLY THE WORKLOAD.

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.