What was found
(CAN) DURING FLIGHT, PILOT FOUND THE CONTROLS TO BECOME UNRESPONSIVE (LOSS OF FULL SENSE OF OPERATION). FAR MORE FWD CYCLIC WAS REQUIRED AND HIGHER COLLECTIVE PITCH THEN NORMAL. PILOT LANDED THE ACFT WITHOUT INCIDENT. ANOTHER ACFT WITH AN AME WAS SENT TO THIS ACFT`S LOCATION TO RECOVER THE CREW. AME FOUND THE CAUSE TO BE A CRACKED JACKSHAFT PN A337-1. ONCE THE PART WAS PROCURED THE JACKSHAFT WAS REPLACED AND THE ACFT RESUMED NORMAL OPERATION. THE JACKSHAFT TTSN IN UNKNOWN AS THIS IS NOT A LIFE LIMITED ITEM HOWEVER THE ACFT IS 4274.2 TTSN. THE ACFT HAD BEEN FLOWN LESS THAN 10 HOURS SINCE ITS LAST INSP.