Narrative:

We approached gate at idle thrust in night VMC conditions. The ramp was snow covered. We had 2 wing walkers and a marshaler. The ramp was clear of equipment, except an air cart under the jetway and attached to a truck. The towbar was visually aligned with the snow shoveled lead-in line. There was a metal chock to the right of the B737 stop line, and the marshaler had illuminated wands. The aircraft was stopped at the marshalers signal, and we experienced excessive vibration during the shutdown. The start levers were immediately placed to cutoff, and engine vibration commenced. Upon inspection, we discovered that a pre-conditioned air duct had been ingested into the #1 engine, resulting in foreign object damage (FOD).

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Original NASA ASRS Text

Title: A B737-700 AT NIGHT ON TAXI INTO A GATE, WITH 2 WING WALKERS AND A MARSHALER, INGESTED A PRE-HEATER FLEXIBLE AIR HOSE INTO #1 ENG.

Narrative: WE APCHED GATE AT IDLE THRUST IN NIGHT VMC CONDITIONS. THE RAMP WAS SNOW COVERED. WE HAD 2 WING WALKERS AND A MARSHALER. THE RAMP WAS CLR OF EQUIP, EXCEPT AN AIR CART UNDER THE JETWAY AND ATTACHED TO A TRUCK. THE TOWBAR WAS VISUALLY ALIGNED WITH THE SNOW SHOVELED LEAD-IN LINE. THERE WAS A METAL CHOCK TO THE R OF THE B737 STOP LINE, AND THE MARSHALER HAD ILLUMINATED WANDS. THE ACFT WAS STOPPED AT THE MARSHALERS SIGNAL, AND WE EXPERIENCED EXCESSIVE VIBRATION DURING THE SHUTDOWN. THE START LEVERS WERE IMMEDIATELY PLACED TO CUTOFF, AND ENG VIBRATION COMMENCED. UPON INSPECTION, WE DISCOVERED THAT A PRE-CONDITIONED AIR DUCT HAD BEEN INGESTED INTO THE #1 ENG, RESULTING IN FOREIGN OBJECT DAMAGE (FOD).

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.