A propeller strike can cause unknown hidden damage to the engine or other components,
possibly leading to a catastrophic failure.
Your safety should be the first priority.
Whenever a propeller strike occurs, no matter how minor it appears, there are set
mandatory inspections in place by all propeller, engine and governor manufacturers to
determine the best course of action to follow for your safety, and to be in compliance
with Federal Aviation Regulations.
Some of the determining factors for the propeller, engine and governor course of
Torn, bent or loss of blade tip
Excessive tip or radial play in blades
Vibration or sporadic operation
Loss or drop of RPM in engine
Any of these conditions are reasons for further inspections that include
tear-down or even overhaul of propeller, engine and governor.
IRAN - Engine Tear-Down Inspections
In addition to prop-strike inspections, IRAN (inspect and repair as necessary) inspections for overspeed, overboost,
hydraulic lock, cracked crankcases, crankshaft replacement, as well as fuel and
oil contamination are also available.
IRAN Procedures include:
Engines disassembled and cleaned for inspection
Non-destructive testing of steel parts by magnetic particle inspection, ultrasound, and 10 power visual aid
Non-destructive testing of aluminum parts by liquid penetrant inspection as well as 10 power visual aid
All parts within the scope of the inspection are dimensional checked with calibrated measuring devices
Crankshafts are polished and measured and bushings are replaced
All parts are replaced per the manufacturer's requirements for the given inspection including: seals, gaskets, rod
bearings, main bearings, rod bolts, rod nuts, all gear bolts, woodruff keys, counter weight pins, counter weight
plates and counter weight retention clips
Engines are painted as a complete assembly
Finally all engines are test run per manufacturer's recommendations using an actual flight propeller for proper
thrust load and governor for proper system operations check