Figure 2-10.—Zero indexing the compressor rotor.damage. Beginning with the third stage, if a slight tiltingof the blade or raising of the blade platform is observed,suspect blade root failure.This condition requiressuspended engine operation until the condition has beenevaluatedCOMPRESSOR DAMAGE.— In tie followingparagraphs, redescribe some of the damage you mayfind during an engine inspection. You can find thecondition codes used to describe engine damage infoldout table 2-1.Airfoil and Tip Cracks.— Cracks in thecompressor hardware are difficult to detect because theyare tight and shallow in depth. You can miss these subtledefects because of deteriorated borescope optics or ifyou rotate the rotor too fast. You should record all crackinformation relative to the stage, area, magnitude,direction, and adjacent blade condition.Cracked Dovetail.— A cracked dovetail of a blademay lead to blade loss. The location of the blade willdetermine the extent of engine damage. Before theactual catastrophic failure of the blade, the separatedcrack in the dovetail will be evident by a leaning bladeplatform. You can find this fault by using the borescopeto inspect each blade platform. The leaning bladeplatform will be higher than the adjacent nonleaningblades.e A “leaner” is a blade that has a crack on the aft2-10
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