What happened
During a pushback from the gate, a tug driver attempted to position the nose wheel on a painted ramp stop mark, known as the 'T'. While maneuvering toward this mark, the aircraft's right horizontal stabilizer struck a pedestrian walkway located between concourses.
Company procedures require tug drivers to place the nose wheel on the 'T' during pushback operations. This specific procedure had been previously discontinued at this gate because the construction of the new pedestrian walkway left insufficient clearance for the maneuver. On the morning of the accident, the ramp coordinator notified the ramp 1 supervisor that pushbacks to the 'T' would resume that day. Although the supervisor requested confirmation due to concerns regarding clearance, the instruction was reconfirmed that all gates on ramp 1 would use the 'T'.
During the event, ramp control cleared the flight to push to the 'T', and the captain relayed this clearance to the tug driver. The wing walkers were properly positioned for the operation. As the aircraft reached approximately 20 feet from the walkway, the right wing walker identified the impending collision and signaled the tug driver to stop. However, the tug driver was focused on positioning the nose wheel on the 'T' and did not see the signal in time to halt the movement. The impact occurred approximately 10 feet before the aircraft reached the 'T'.
Findings
Investigation into the incident revealed that the completed walkway had significantly reduced the available ramp space, leaving an area substantially shorter than the length of the airline's operated aircraft. Furthermore, the 'T' stop mark had not been repositioned to account for the new infrastructure.
It was noted that there is no voice communication capability between the crew chief at the gate, the tug driver, and the wing walkers. Additionally, while the decision to resume pushbacks to the 'T' originated with the ACS project manager, this change was not coordinated with the ground operations safety supervisor prior to implementation.