What was found
INSTRUCTOR PILOT ACTING AS STUDENT FOR CFI TRAINING WAS AT THE CONTROLS AND WAS APPROX 4 MILES WEST OF AIRPORT (RVS). WITHIN A FEW SECONDS OF PLACING THE GEAR HANDLE IN THE DOWN POSITION FLAMES CONSUMED THE AREA OF THE RUDDER PEDALS. AN EMERGENCY WAS DECLARED AND A DESCENT WAS INITIATED TO A FIELD BELOW. CABIN WAS FILLED WITH SMOKE AND PILOT PLACED HIS HEAD OUT THE WINDOW FOR VISUAL REF ACFT LANDED IN THE FIELD. BOTH PILOTS EXITED THE ACFT AND WITHIN APPROX 30 SECONDS THE ACFT WAS ENGULFED IN FLAMES. HYD POWER PACK ELECTRICAL CONNECTION SHOWED EVIDENCE OF ARCING TO CASE.