Covington Aircraft - Quality Service

What happens if your prop has made contact with something? The standard repair for a prop strike engine is to first remove the crankshaft. The crankshaft will go through two major inspections at this time. The first is a dial indication check (this checks to see if the shaft is bent or twisted). The second is the magnetic particle inspection test (this test is to detected any cracking on the crankshaft). The main bearings will go through the same inspection process as an overhauled unit, with the exception of the thrust bearing. The thrust bearing is automatically rejected because it absorbs much of the shock in a prop strike incident. When the cylinders are removed they have a leak test and AD 99-11-02 is complied with (in accordance with Pratt & Whitney S.B.1787). The blower and rear case section is disassembled so that all the gearing and bearings removed can be inspected, if all is well they will then be magnetic particle inspected. (Note: The R-985 6515 supercharger intermediate gear is automatically rejected per the manual in a sudden stoppage or shock load incident.) The engine case paint is not removed from the cases so only a visual inspection is performed. New gaskets and seals are used in the assembly of the engine. The engine then goes through the same test run procedure as an overhauled engine. The cost to have this inspection done, barring rejected parts, is about 1/3 the cost of an overhaul.