Federal Aviation Administration October 25, 2011 – Federal Register Recent Federal Regulation Documents

We propose to supersede an existing airworthiness directive (AD) that applies to all RR RB211-535E4-37, -535E4-B-37, -535E4-B-75, and -535E4-C-37 turbofan engines. The existing AD currently requires performing initial and repetitive visual and fluorescent penetrant inspections (FPI) of the low-pressure (LP) turbine stage 1, 2, and 3 discs to detect cracks in the discs. Since we issued that AD, we determined that the definition of shop visit is too restrictive in the existing AD. This proposed AD would continue to require those inspections and would change the definition of a shop visit to be less restrictive. We are proposing this AD to correct the definition of shop visit, and to detect cracks in the LP turbine stage 1, 2, and 3 discs, which could result in an uncontained release of LP turbine blades and damage to the airplane.

We propose to adopt a new airworthiness directive (AD) for the products listed above. This proposed AD would require repetitive detailed inspections for discrepancies of the horizontal stabilizer ballscrew assembly; repetitive lubrication of the horizontal stabilizer trim control system; repetitive measurements for discrepancies of the ballscrew to ballnut freeplay; and corrective actions if necessary. This proposed AD was prompted by a report of extensive corrosion of the ballscrew of the drive mechanism of the horizontal stabilizer trim actuator. We are proposing this AD to prevent undetected failure of the primary and secondary load paths for the ballscrew in the horizontal stabilizer, which could lead to loss of control of the horizontal stabilizer and consequent loss of control of the airplane.

This action establishes Class E airspace at Tatitlek, AK, to accommodate the creation of one standard instrument approach procedure at the Tatitlek Airport. The FAA is taking this action to enhance safety and management of Instrument Flight Rules (IFR) operations at the Tatitlek Airport.

This rule establishes, amends, suspends, or revokes Standard Instrument Approach Procedures (SIAPs) and associated Takeoff Minimums and Obstacle Departure Procedures for operations at certain airports. These regulatory actions are needed because of the adoption of new or revised criteria, or because of changes occurring in the National Airspace System, such as the commissioning of new navigational facilities, adding new obstacles, or changing air traffic requirements. These changes are designed to provide safe and efficient use of the navigable airspace and to promote safe flight operations under instrument flight rules at the affected airports.