Narrative:

After starting engines, I motioned for the first officer to call for taxi. We became distraction with other cockpit duties. After getting those matters resolved, I began taxiing, thinking we had clearance. The end of the runway was at the end of the ramp, so we did not cross any active runways. No conflicts with other aircraft or vehicles existed. This is a classic example of flying the trip regularly and being a creature of habit or repetition, then getting distraction in other duties and reacting out of habit.

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Original NASA ASRS Text

Title: B727 CREW TAXIES WITHOUT CLRNC AT TYS.

Narrative: AFTER STARTING ENGS, I MOTIONED FOR THE FO TO CALL FOR TAXI. WE BECAME DISTR WITH OTHER COCKPIT DUTIES. AFTER GETTING THOSE MATTERS RESOLVED, I BEGAN TAXIING, THINKING WE HAD CLRNC. THE END OF THE RWY WAS AT THE END OF THE RAMP, SO WE DID NOT CROSS ANY ACTIVE RWYS. NO CONFLICTS WITH OTHER ACFT OR VEHICLES EXISTED. THIS IS A CLASSIC EXAMPLE OF FLYING THE TRIP REGULARLY AND BEING A CREATURE OF HABIT OR REPETITION, THEN GETTING DISTR IN OTHER DUTIES AND REACTING OUT OF HABIT.

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.