Narrative:

ATC instructed us to go direct to gij out of 14000 ft from a 090 degree heading. Out of 14000 ft I turned direct gij but ATC advised us that we were given an amended clearance that instructed us to stay on a 090 degree heading which ATC said we acknowledged. I didn't hear the amended clearance and the copilot was not sure that the clearance was for us. We immediately turned back to a 090 degree heading with no apparent conflict with another aircraft.

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Original NASA ASRS Text

Title: FLC OF AN MD SUPER 80 FAILED TO HOLD ATC INSTRUCTED HEADING BY TURNING DIRECTLY TO THE NEXT FIX AS THEY BELIEVED THAT THEY WERE INSTRUCTED. HOWEVER, ATC INTERVENED AND ADVISED THEM THAT THEY HAD ACKNOWLEDGED THE HEADING CLRNC TO WHICH THEY IMMEDIATELY RETURNED.

Narrative: ATC INSTRUCTED US TO GO DIRECT TO GIJ OUT OF 14000 FT FROM A 090 DEG HDG. OUT OF 14000 FT I TURNED DIRECT GIJ BUT ATC ADVISED US THAT WE WERE GIVEN AN AMENDED CLRNC THAT INSTRUCTED US TO STAY ON A 090 DEG HDG WHICH ATC SAID WE ACKNOWLEDGED. I DIDN'T HEAR THE AMENDED CLRNC AND THE COPLT WAS NOT SURE THAT THE CLRNC WAS FOR US. WE IMMEDIATELY TURNED BACK TO A 090 DEG HDG WITH NO APPARENT CONFLICT WITH ANOTHER ACFT.

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.