Narrative:

Aircraft 1 and 2 were on parallel routes swbnd at FL350. Aircraft 1 asked for route change to avoid WX. Route requested would have maintained separation from aircraft 2. Clearance was issued to deviate as required, direct to next fix on original route. When able, aircraft 1 turned to a heading of 15-20 degree further than heading requested in route change. At approximately the time aircraft 1 was established on his deviation heading, the conflict was noted. Aircraft 1 was told to turn to a heading that would maintain separation. Pilot of aircraft 1 balked and several xmissions were necessary to get the pilot to turn. He was simultaneously issued an altitude change and told he could resume his deviation upon reaching his new assigned altitude. Aircraft #2 was also turned but separation was lost.

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Original NASA ASRS Text

Title: ACR DEVIATION AROUND WX CONFLICTED WITH ANOTHER ACFT ON A PARALLEL ROUTE.

Narrative: ACFT 1 AND 2 WERE ON PARALLEL ROUTES SWBND AT FL350. ACFT 1 ASKED FOR ROUTE CHANGE TO AVOID WX. ROUTE REQUESTED WOULD HAVE MAINTAINED SEPARATION FROM ACFT 2. CLRNC WAS ISSUED TO DEVIATE AS REQUIRED, DIRECT TO NEXT FIX ON ORIGINAL ROUTE. WHEN ABLE, ACFT 1 TURNED TO A HDG OF 15-20 DEG FURTHER THAN HDG REQUESTED IN ROUTE CHANGE. AT APPROX THE TIME ACFT 1 WAS ESTABLISHED ON HIS DEVIATION HDG, THE CONFLICT WAS NOTED. ACFT 1 WAS TOLD TO TURN TO A HDG THAT WOULD MAINTAIN SEPARATION. PLT OF ACFT 1 BALKED AND SEVERAL XMISSIONS WERE NECESSARY TO GET THE PLT TO TURN. HE WAS SIMULTANEOUSLY ISSUED AN ALT CHANGE AND TOLD HE COULD RESUME HIS DEVIATION UPON REACHING HIS NEW ASSIGNED ALT. ACFT #2 WAS ALSO TURNED BUT SEPARATION WAS LOST.

Data retrieved from NASA's ASRS site as of August 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.