Airworthiness Directives; Bombardier Model CL-600-2B19 (Regional Jet Series 100 & 440) Airplanes
The FAA proposes to supersede an existing airworthiness directive (AD) that applies to certain Bombardier Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes. The existing AD currently requires repetitive detailed and eddy current inspections of the main fittings of the main landing gears (MLG) to detect discrepancies, and related investigative/corrective actions if necessary. The existing AD also requires servicing the shock strut of the MLGs; inspecting the shock strut of the MLGs for nitrogen pressure, visible chrome dimension, and oil leakage; and servicing any discrepant strut. This proposed AD would require installing a new, improved MLG main fitting, which would terminate the repetitive inspection and servicing requirements of the existing AD. This proposed AD results from stress analyses that showed certain main fittings of the MLGs are susceptible to premature cracking, starting in the radius of the upper lug. We are proposing this AD to detect and correct premature cracking of the main fittings of the MLGs, which could result in failure of the fittings and consequent collapse of the MLGs during landing.
Airworthiness Directives; Rolls-Royce Deutschland Ltd & Co KG Tay 611-8, Tay 620-15, Tay 650-15, and Tay 651-54 Series Turbofan Engines
The FAA proposes to adopt a new airworthiness directive (AD) for Rolls-Royce Deutschland Ltd & Co KG (RRD) Tay 611-8, Tay 620-15, Tay 650-15, and Tay 651-54 series turbofan engines, with certain low pressure (LP) compressor modules installed. This proposed AD would require an ultrasonic inspection (UI) of LP compressor fan blades for cracks, within 30 days after the effective date of the proposed AD on certain serial number (SN) Tay 650-15 engines. This proposed AD would also require repetitive UIs of LP compressor fan blades on all engines. This proposed AD would also require, for Tay 650-15 and Tay 651-54 engines, UIs of LP compressor fan blades whenever the blade set is removed from one engine and installed on a different engine. This proposed AD results from a report that a set of LP compressor fan blades failed before reaching the LP compressor fan blade full published life limit. We are proposing this AD to prevent LP compressor fan blades from failing due to blade root cracks, leading to uncontained engine failure and damage to the airplane.
Airworthiness Directives; Boeing Model 727 Airplanes
The FAA is adopting a new airworthiness directive (AD) for certain Boeing Model 727 airplanes. This AD requires repetitive measurements of the freeplay of the left and right outboard aileron balance tabs and of the upper and lower rudder tabs, and related investigative/corrective actions if necessary. This AD also requires repetitive lubrication of the hinge bearings and rod end bearings of the outboard aileron balance tabs. This AD results from reports of freeplay-induced vibration of the outboard aileron balance tabs and rudder tabs. We are issuing this AD to prevent excessive vibration of the airframe during flight, which could result in divergent flutter and loss of control of the airplane.