Narrative:

Received clearance to turn left to 010 degrees. This came during an otherwise busy time. I dialed the heading in but failed to pull the knob, thinking that I was already in heading select, but I should have pulled on the knob because I was not. A few moments later ATC commented that I had not turned and assigned me further left to 340 degrees. I should have looked at what lateral mode was displayed. I should have looked to see if the airplane was doing what I wanted it to. But mostly, I should have pulled on the knob. Supplemental information from acn 353809: the captain was hand flying and never pulled the heading select knob and stayed in VOR track. We were distraction by checklist items and changing aircraft confign.

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Original NASA ASRS Text

Title: AN MD80 CAPT TURNED THE HDG SELECT KNOB, BUT FAILED TO PULL IT TO PUT THE FLT DIRECTOR INTO HDG SELECT MODE. ERROR ADMITTED. TRACK HDG DEV.

Narrative: RECEIVED CLRNC TO TURN L TO 010 DEGS. THIS CAME DURING AN OTHERWISE BUSY TIME. I DIALED THE HDG IN BUT FAILED TO PULL THE KNOB, THINKING THAT I WAS ALREADY IN HDG SELECT, BUT I SHOULD HAVE PULLED ON THE KNOB BECAUSE I WAS NOT. A FEW MOMENTS LATER ATC COMMENTED THAT I HAD NOT TURNED AND ASSIGNED ME FURTHER L TO 340 DEGS. I SHOULD HAVE LOOKED AT WHAT LATERAL MODE WAS DISPLAYED. I SHOULD HAVE LOOKED TO SEE IF THE AIRPLANE WAS DOING WHAT I WANTED IT TO. BUT MOSTLY, I SHOULD HAVE PULLED ON THE KNOB. SUPPLEMENTAL INFO FROM ACN 353809: THE CAPT WAS HAND FLYING AND NEVER PULLED THE HDG SELECT KNOB AND STAYED IN VOR TRACK. WE WERE DISTR BY CHKLIST ITEMS AND CHANGING ACFT CONFIGN.

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.