Summary
The FAA proposes to supersede an existing Priority Letter Airworthiness Directive (AD) for Hartzell Propeller Inc. Model HC-B3TN-5( )/T10282( ) propellers. That Priority Letter AD currently requires initial and repetitive inspections of the blade pilot tube bore area. This proposed AD would require the same inspections. This proposed AD results from a review of all currently effective ADs. That review determined that Priority Letter AD 88-24-15 was not published in the Federal Register to make it effective to all operators, as opposed to just the operators who received actual notice of the original Priority Letter AD. This proposed AD also results from the discovery that the original AD omitted an airplane model with a certain Supplemental Type Certificate (STC) from the applicability. We are proposing this AD to prevent possible blade failure near the hub which can result in blade separation, engine separation, damage to the airplane, and possible loss of the airplane.