SA-227 AC Metro III
Flight Crew Air Transport Pilot (ATP)
Aircraft Equipment Problem Critical; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor; Ground Excursion Taxiway
Aircraft Aircraft Damaged; General Maintenance Action
Aircraft; Weather
Nose wheel steering inoperative (deferred) was cleared to taxi to runway. When I passed the threshold of [another runway] [a] pilot reported brake fire. I lost LH brakes; then RH brakes [and the] aircraft veered right. Left taxiway [with] nose gear off pavement. Did emergency shut down [and] got fire extinguisher; went to LH Tires; put out fire. Then there was fire on RH brakes; put out fire on that brake. Noticed fire on LH brake; went back to it [but] could not put out fire as I was out of extinguisher. Standing in front of LH brakes number 2 tire blew out. No damage to aircraft or me as I was in front of tires; knowing they explode and blow out from the side. Had quartering tail wind which made it hard to taxi straight hence had to use more brakes and differential thrust. Weight of aircraft was 13;346. Fire trucks soon arrived to put out fire. I was the only one involved. Maintenance came out; towed aircraft back to taxiway; changed tire; and towed it back to ramp. [They then] moved cargo from aircraft to new plane [and I] flew the rest of the trip. Don't taxi heavy metro with light brakes with no nose wheel steering over long distances.
SA-227AC Captain reported experiencing a brake fire during an extended taxi with nosewheel steering inoperative.