What was found
(CAN) AFTER TOUCHDOWN PILOTS NOTICE ERRATIC ENGINE INDICATIONS. DURING THEIR COCKPIT MANAGEMENT THE STUDENT NOTICE SMOKE FROM THE COWLING. THE PILOTS NOTIFIED TOWER AND EVACUATED THE ACFT AT WHICH TIME THEY SAW FLAMES FROM THE BOTTOM COWLING. THE PORTABLE EXTINGUISHER WAS USED TO EXTINGUISH THE FIRE. INITIAL INVESTIGATION SHOWS A BROKEN RT AFT EXHAUST PIPE MELTING THE PLASTIC COOLANT BOTTLE AND PLASTIC SHEETING ON CONTROL CABLE WHICH MAY HAVE BEEN BURNING AT THE TIME OF THE INCIDENT.