Narrative:

On taxi in to gate Z at pdx, aircraft left wing struck a deicing truck that had been parked partially over 'circle of safety' line. As the captain, the aircraft was under my control. I was under the direction of the marshaller, and I had received a 'thumbs up' from both wing walkers. The aircraft was within 2 or 3 ft of the parking line and was moving only 1 or 2 mph. The copilot and I felt a 'slight shudder' and immediately stopped the aircraft. The marshaller was unaware that we had struck the truck, and continued to urge us forward with the wands. It was not until the left wing walker ran to her that she realized we had struck the vehicle. The copilot and I thought we might have run over a chock -- the impact was that slight. Damage was very minimal, but unnerving just the same. This was a classic chain of events scenario. There were lots of baggage carts on the ramp. Because of the congestion, the deicing truck driver left the truck slightly over the 'circle of safety' line. When the ground crew went out to marshal in the aircraft, they didn't check to see if the area was clear. The rain partially obscured the safety lines so the crew was unaware the truck was partially over the line, and finally when the left wing walker realized that a collision was imminent, his signal for an emergency stop went unheeded because the marshaller had lost sight of the wing walker.

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Original NASA ASRS Text

Title: A B737-400, BEING GUIDED IN TO A GATE WITH A MARSHALLER AND 2 WING WALKERS, STRUCK A PARKED TRUCK INCURRING DAMAGE TO THE L WINGTIP.

Narrative: ON TAXI IN TO GATE Z AT PDX, ACFT L WING STRUCK A DEICING TRUCK THAT HAD BEEN PARKED PARTIALLY OVER 'CIRCLE OF SAFETY' LINE. AS THE CAPT, THE ACFT WAS UNDER MY CTL. I WAS UNDER THE DIRECTION OF THE MARSHALLER, AND I HAD RECEIVED A 'THUMBS UP' FROM BOTH WING WALKERS. THE ACFT WAS WITHIN 2 OR 3 FT OF THE PARKING LINE AND WAS MOVING ONLY 1 OR 2 MPH. THE COPLT AND I FELT A 'SLIGHT SHUDDER' AND IMMEDIATELY STOPPED THE ACFT. THE MARSHALLER WAS UNAWARE THAT WE HAD STRUCK THE TRUCK, AND CONTINUED TO URGE US FORWARD WITH THE WANDS. IT WAS NOT UNTIL THE L WING WALKER RAN TO HER THAT SHE REALIZED WE HAD STRUCK THE VEHICLE. THE COPLT AND I THOUGHT WE MIGHT HAVE RUN OVER A CHOCK -- THE IMPACT WAS THAT SLIGHT. DAMAGE WAS VERY MINIMAL, BUT UNNERVING JUST THE SAME. THIS WAS A CLASSIC CHAIN OF EVENTS SCENARIO. THERE WERE LOTS OF BAGGAGE CARTS ON THE RAMP. BECAUSE OF THE CONGESTION, THE DEICING TRUCK DRIVER LEFT THE TRUCK SLIGHTLY OVER THE 'CIRCLE OF SAFETY' LINE. WHEN THE GND CREW WENT OUT TO MARSHAL IN THE ACFT, THEY DIDN'T CHK TO SEE IF THE AREA WAS CLR. THE RAIN PARTIALLY OBSCURED THE SAFETY LINES SO THE CREW WAS UNAWARE THE TRUCK WAS PARTIALLY OVER THE LINE, AND FINALLY WHEN THE L WING WALKER REALIZED THAT A COLLISION WAS IMMINENT, HIS SIGNAL FOR AN EMER STOP WENT UNHEEDED BECAUSE THE MARSHALLER HAD LOST SIGHT OF THE WING WALKER.

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.