#4 ENG OF A B747 STRIKES FENCE DURING PARKING AT AN ALTERNATE ARPT. GND PERSONNEL MARSHALLERS FAILED TO GUIDE ACFT CLR OF ALL OBSTRUCTIONS.

Narrative

FLT FROM TOKYO (NRT) TO SFO. AFTER A MISSED APCH AT SFO DUE TO ZERO VISIBILITY; FLEW TO ALTERNATE (OAKLAND). ON TAXI IN TO REMOTE PARKING 2 MARSHALLERS WERE GUIDING US IN; ONE IN FRONT WITH WANDS; ONE RIGHT WING WALKER. WE HAD DISCUSSED AS A CREW A ROW OF VERY TALL LIGHT POLES THAT WE WERE CONCERNED ABOUT ON PARKING. THE CAPT WAS TAXIING; WATCHING THE NOSE MARSHALLER. I WAS WATCHING THE R WINGTIP; THE WING WALKER; MONITORING BRAKE PRESSURE; AND FORWARD SPD. AS WE TAXIED AT APPROX 3 KTS WATCHING THE LIGHT POLE CLRNC FROM THE R WINGTIP; WE STOPPED OBSERVING THE #4 ENG COWL SCRAPE A FENCE. ULTIMATELY PAINT SCRATCH FOUND ON BOTTOM OF #4 ENG COWL. NO DENTED METAL! WING WALKER WAS NOT WATCHING THE ENG COWL; BUT ONLY THE WINGTIP CLRNC. THE FORWARD MARSHALLER APPEARED TO BE FIXED ON THE NOSEWHEEL ONLY. THE COMS AND/OR HAND SIGNALS WERE NOT STANDARD BTWN THE MARSHALLERS AND BTWN THE MARSHALLERS AND FLC. THE MARSHALLERS DIDN'T APPEAR TO HAVE A CLR IDEA OF THEIR JOBS; PROBABLY LIMITED EXPERIENCE WITH B747'S EVEN THOUGH OAK IS OUR B747 HVY MAINT BASE. WE INITIATED THE STOP WHEN IT BECAME APPARENT THERE WAS CONFUSION BTWN THE MARSHALLERS. OTHER FACTORS: RAMP UNEVEN -- NOT LEVEL. FENCE HAS NUMEROUS DOG LEGS þ NOT A STRAIGHT LINE. FENCE APPEARS TO VARY IN HT. AS PLTS WE CAN SEE VERY LITTLE OF OUR ACFT. WE ARE VERY DEPENDENT ON ACCURATE MARSHALLERS.