The Hiper DC-3 took off from Amritsar at 11:15 for a flight to Srinagar. Last radio contact with the flight was at 11:23 when the crew reported 25 miles from Amritsar. Nothing more was heard from the flight. PROBABLE CAUSE: “The accident was caused by structural failure of the aircraft in the air following overstressing as a result of loss of control. The loss of control was caused by improper rigging of the rudder bungee system which helps to prevent the marked tendency of the rudder of the Hiper Dakota to reverse or lock under conditions of yawed turn and/or encountering a severe side gust. It is equally likely that mal-functioning or improper operation of the autopilot may have initiated a yaw and accentuated the tendency of the rudder to lock.”