58-02-01: Rotor Blade Bond Separation

58-02-01 BELL: Applies to All Model 47J Helicopters, Using Main Rotor Blade P/N 47- 110-401-7, -9 and -11. Due to the possibility of a faulty bond between the butt plate laminates and the wood portion of the blade, causing a subsequent separation of the subject parts with possible catastrophic results, the following mandatory inspection is required: 1. Inspect butt plate laminates for indication of bond separation by grasping blade at tip and coning blade downward slightly after static stop is contacted, then coning blade upward to extent that tip is above level line of yoke. If separation is found no repair is allowed, remove blades and notify Bell Helicopter Corporation. Inspection required after each refueling until blades accumulate a total of 50 hours flight time and then daily thereafter. 2. Inspect on one-time basis butt plate laminates for bonding voids by tapping lightly completely around exposed surface of each laminate with a four or six inch wrench. Each laminate will have a different sound; however, an obvious variation in sound on an individual laminate tends to indicate a void. If void indicated, notify Bell Helicopter Corporation immediately. This supersedes AD 58-01-02.