ACFT EVACED WHEN A FIRE DEVELOPS IN THE L LNDG GEAR.

Narrative

FLT SFO-SEA WAS NORMAL; NON EVENTFUL FLT UNTIL EXITING RWY 16R AT SEATTLE TACOMA INTL. ARPT. AFTER XING RWY 16L AT SEA; GND CTL INDICATED THAT SMOKE WAS OBSERVED COMING FROM THE L MAIN GEAR AREA. I DID NOT TAKE THIS RPT LIGHTLY AND IMMEDIATELY CHKED THE BRAKE TEMP GAUGE FOR THE L MAIN BRAKES. THIS INDICATED THAT THE BRAKES WERE NORMAL (ABOUT 100 DEG) I PASSED THIS INFO ONTO GND CTL AND THEY RESPONDED THAT THE SMOKE WAS DISSIPATING AND NOW LOOKED VERY LIGHT. THEY SAID THEY COULDN'T SEE ANY SMOKE WITHOUT THE ASSISTANCE OF BINOCULARS. I CONTINUED TAXIING INTO THE GATE AREA AND WAS THEN ADVISED BY A COMPANY PLT IN A COMPANY ACFT THAT THE SMOKE WAS BEGINNING TO RECUR. AT THIS PT. I REQUESTED FIRE TRUCKS AND CREWS FOLLOW THE ACFT TO THE GATE. I ALSO ADVISED OUR MAINT TO HAVE SOMEONE MEET THE ACFT AT THE GATE. AFTER COMING TO A COMPLETE STOP AT THE GATE; WE WERE INFORMED BY RADIO THAT FLAMES WERE VISIBLE IN THE L MAIN GEAR AREA. AT THIS TIME; WE INSTRUCTED THE 4 FLT ATTENDANTS TO EVAC THE ACFT AND COMPLETED EVAC CHKLIST. APPROX 70 PAX EVACED OUT THE TAILCONE EXIT AND SLIDE AND THE REMAINDER OF THE PAX DEPLANED OUT THE FRONT L DOOR VIA THE JETWAY; WHICH I INSTRUCTED THE OPERATOR TO MOVE UP TO THE ACFT AFTER IT WAS STOPPED IN THE GATE AREA. WE WERE THEN TOLD BY A PORT OF SEATTLE EMPLOYEE TO STOP THE EVAC BECAUSE THE FIRE WAS UNDER CTL. I PROCEEDED TO INSTRUCT THE FLT ATTENDANTS TO KEEP THE PAX COMING OUT THE L FRONT DOOR AND INTO THE TERMINAL AREA WITHOUT DELAY. THE PORT OF SEATTLE EMPLOYEES MOVED THE PAX THAT EVACED OUT THE TAILCONE A SAFE DISTANCE FROM THE ACFT. AS THE CAPT OF THE FLC; I MADE SURE THAT AFTER THE EVAC WAS INITIATED; THAT APPROPRIATE CHKLISTS WERE COMPLETED. NO INJURIES TO THE 137 PAX OR CREW WERE RPTED TO MY KNOWLEDGE. I FEEL IN THIS INSTANCE THE DECISION OF WHEN TO EVAC IS VERY CRITICAL AS WELL AS DIFFICULT. I FEEL A PREMATURE EVAC IS OR WAS NOT WARRANTED; IN THIS SIT; DUE TO THERE BEING NO VISIBLE FLAMES UNTIL ACTUALLY IN THE GATE AREA. HOWEVER AFTER I HEARD THAT FLAMES WERE VISIBLE; MY DECISION TO EVAC WAS AT THIS TIME THE RIGHT DECISION.