THE PILOT REPORTED THAT THE AIRPLANE 'PULLED HARD TO THE RIGHT UPON APPLICATION OF POWER' AND IMPACTED EVERGREEN TREES ON THE RIGHT SIDE OF THE RUNWAY. THE PASSENGER REPORTED THAT DURING THE OCCURRENCE, THE AIRPLANE SLID SIDEWAYS TO THE RIGHT. ALSO, THE PASSENGER SAID THE RIGHT WING CAME UP ABRUPTLY, THEN CAME DOWN HARD AND HIT A TREE. SUBSEQUENTLY, A FIRE ERUPTED AND THE PILOT RECEIVED SERIOUS BURNS. THE RIGHT MAIN LANDING GEAR COLLAPSED, AND THE UPPER BOLT WAS FOUND FRACTURED. HOWEVER, EXAMINATION OF THE BOLT REVEALED THAT IT HAD FAILED IN SHEAR DUE TO DIRECT OVERSTRESS LOADING.