Narrative:

I was assigned to be the wing walker on flight. We were positioned behind the aircraft before departure time and the push tug driver motioned us to come to the push tug. He said the pilot needed about ten minutes to get the paperwork done. After only about 2 to 3 minutes the pilot was ready to go. As we started to walk back to get in position; the push tug driver started to push the aircraft. I was still in front of the wing when I heard the pop of the shear pin breaking because there was a bus driving behind the aircraft and the push tug driver hit the brakes. I was trying to motion to the bus to stop; but he didn't see me. Maintenance came out and inspected the aircraft and everything was ok.

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Original NASA ASRS Text

Title: Wing walker reported a B737's pushback was abruptly stopped as a bus passed behind the aircraft; the tug driver had to stopped rapidly causing the tow bar shear pin to brake. No aircraft damage.

Narrative: I was assigned to be the wing walker on flight. We were positioned behind the aircraft before departure time and the push tug driver motioned us to come to the push tug. He said the pilot needed about ten minutes to get the paperwork done. After only about 2 to 3 minutes the pilot was ready to go. As we started to walk back to get in position; the push tug driver started to push the aircraft. I was still in front of the wing when I heard the pop of the shear pin breaking because there was a bus driving behind the aircraft and the push tug driver hit the brakes. I was trying to motion to the bus to stop; but he didn't see me. Maintenance came out and inspected the aircraft and everything was OK.

Data retrieved from NASA's ASRS site as of July 2013 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.