SHEARER HAD CUT FROM H.GATE TO NO. 43 SHIELD AND HAD STARTED TO TURN TOWARD H.GATE AND CUT MORE BOTTOM FOR PAN LINE TO PUSH OVER WHEN TAIL GATE DRUM IGNITED CHY. APPROX. 3"" OF BOTTOM WAS BEING CUT. OPERATORS TRAMMED SHEARER ABOUT 3 SHIELDS TOWARD H.G. AND EXT. FLAME WITH FIRE EXTINGUISHER.