Narrative:

Flight crew misread departure plate. We thought SID stated 'fly runway heading.' SID called for a 30 degree turn to the left. (Probably local noise abatement.) departure control asked why we didn't make turn. We responded that we thought departure procedure called for runway heading.

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Original NASA ASRS Text

Title: MLG ACFT ON SID DEP FLEW RWY HDG INSTEAD OF PUBLISHED 30 DEG TURN.

Narrative: FLC MISREAD DEP PLATE. WE THOUGHT SID STATED 'FLY RWY HDG.' SID CALLED FOR A 30 DEG TURN TO THE L. (PROBABLY LCL NOISE ABATEMENT.) DEP CTL ASKED WHY WE DIDN'T MAKE TURN. WE RESPONDED THAT WE THOUGHT DEP PROC CALLED FOR RWY HDG.

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.