Narrative:

While preparing for flight from bwi; I sitting in the captain's seat on the flight deck at our gate and noticed an unattended tractor with empty luggage carts attached beginning to roll backwards. Concerned that the tractor and carts might hit the jet or tug; I immediately left the flight deck; ran down the jetway steps; and I jumped onto the tractor driver seat while applying the foot brake. The tractor came to a stop. I noticed that the parking brake had been 'set' in the 'up' position. It was apparent to me that the parking brake was not working properly or had not been set properly. The tractor had been on a slightly sloping portion of the flight line and had started to move backwards causing the carts behind the tractor to form a 'train wreck' zig zag pattern which helped to stop the tractor and carts from moving back any further. A ramp agent and a ramp supervisor approached the tractor while I was holding the foot brake. They had not seen the tug moving on its own. I asked the ramp supervisor to remove the tractor from service until it could be repaired. The ramp supervisor seemed to ignore what I had just said; moved the tractor to a flat portion of the ramp; and left the tractor and trailers unattended near the jet.

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Original NASA ASRS Text

Title: An air carrier Captain saw a free rolling baggage tractor and exited his aircraft to stop it and set the brake; which turn out to be faulty. Ground personnel were unconcerned and ignored the Captain's request to remove the vehicle from service.

Narrative: While preparing for flight from BWI; I sitting in the Captain's seat on the flight deck at our gate and noticed an unattended tractor with empty luggage carts attached beginning to roll backwards. Concerned that the tractor and carts might hit the jet or tug; I immediately left the flight deck; ran down the jetway steps; and I jumped onto the tractor driver seat while applying the foot brake. The tractor came to a stop. I noticed that the parking brake had been 'set' in the 'up' position. It was apparent to me that the parking brake was not working properly or had not been set properly. The tractor had been on a slightly sloping portion of the flight line and had started to move backwards causing the carts behind the tractor to form a 'train wreck' zig zag pattern which helped to stop the tractor and carts from moving back any further. A Ramp Agent and a Ramp Supervisor approached the tractor while I was holding the foot brake. They had not seen the tug moving on its own. I asked the Ramp Supervisor to remove the tractor from service until it could be repaired. The Ramp Supervisor seemed to ignore what I had just said; moved the tractor to a flat portion of the ramp; and left the tractor and trailers unattended near the jet.

Data retrieved from NASA's ASRS site as of April 2012 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.