Federal Aviation Administration June 5, 2014 – Federal Register Recent Federal Regulation Documents

We propose to supersede airworthiness directive (AD) 2013-15- 09, which applies to all Pratt & Whitney Division (PW) PW4074, PW4074D, PW4077, PW4077D, PW4084D, PW4090, and PW4090-3 turbofan engine models with certain second-stage high-pressure turbine (HPT) air seals, installed. AD 2013-15-09 currently requires initial and repetitive inspections for cracks in second-stage HPT air seals. Since we issued AD 2013-15-09, we received reports of cracking in the original location on two additional part numbers (P/Ns) as well as reports of through- cracks in a new location in the second-stage HPT air seal. PW has developed a redesigned second-stage HPT air seal that addresses the cracking condition in both locations. This proposed AD would expand the applicability of AD 2013-15-09 to include additional P/Ns, require replacement of the mating hardware if the second-stage HPT air seal is found with a through-crack, and add mandatory terminating action to the repetitive inspections. We are proposing this AD to prevent failure of the second-stage HPT air seal, which could lead to uncontained engine failure and damage to the airplane.

This action amends Class E Airspace at Newnan, GA, as new Standard Instrument Approach Procedures have been developed at Newnan Coweta County Airport. This enhances the safety and management of aircraft operations at the airport. This action also updates the geographic coordinates of airport.