INDIANAPOLIS (AP) _ A federal agency's preliminary report on the crash of a home-built plane into a south-central Indiana house says the pilot was working “frantically'' on a propeller switch just before the crash.
 
  The preliminary report by the National Transportation Safety Board was released Tuesday. It says the plane was approaching a runway to perform a practice landing at Columbus' airport on July 25 when the plane's passenger radioed that the engine was running fast and pilot Gerald H. Clayton was “working frantically on a switch for the propeller'' but the airplane was still descending.
 
  Experimental Aircraft Association spokesman Dick Knapinski  says the report doesn't make clear whether the propeller was still working. But he says he's sure that's something the NTSB will investigate.
 
  Clayton died Saturday at an Indianapolis hospital.