Incident Overview
An airplane that had just been pushed back from a gate was taxiing in a non-movement area when it collided with a tug. The captain felt the impact but believed it was a blown tire. Neither the captain nor any other cockpit crew member saw the tug before the collision.
Witness Accounts
All witnesses reported that the tug did not brake or swerve prior to the collision.
Tug and Driver Information
Examination of the damaged tug and its maintenance records revealed no mechanical problems. No deficiencies were found in the driver's training records. The driver had been on a two-week vacation, and this was his first day back on the job. He had been driving the tug since 0430 without any reported mechanical issues.
Medical Evaluation
The emergency room doctor stated that no symptoms were detected of any medical events that could have caused the driver to lose consciousness.
Driver's Recollection
The driver recalled that while driving the tug, he dropped his water container, and the last thing he could remember was reaching down for it.