Airworthiness Directives; Pratt & Whitney JT8D-209, -217, -217A, -217C, and -219 Series Turbofan Engines

요약

The FAA proposes to supersede an existing airworthiness directive (AD) for Pratt & Whitney (PW) JT8D-209, -217, -217A, -217C, and -219 series turbofan engines. That AD requires initial and repetitive torque inspections of the 3rd stage and 4th stage low- pressure turbine (LPT) blades for shroud notch wear and replacement of the blade if wear limits are exceeded. That AD also requires replacing LPT-to-exhaust case bolts and nuts with bolts and nuts made of Tinidur material. This proposed AD would require the same actions but would require replacement of the LPT-to-exhaust case bolts and nuts with longer bolts made of Tinidur material, with nuts made of Tinidur material, and installation of crushable sleeve spacers on the bolts. This proposed AD results from nine reports of failure of Tinidur material LPT-to-exhaust case bolts since AD 2005-02-03 became effective. We are proposing this AD to prevent turbine blade failures that could result in uncontained engine debris and damage to the airplane.