Airworthiness Directives; Beechcraft Corporation Airplanes
We propose to supersede airworthiness directive (AD) 2011-27- 51 that applies to certain Beechcraft Corporation Models 1900, 1900C, and 1900D airplanes. AD 2011-27-51 currently requires inspecting the elevator bob-weight and attaching linkage for correct installation and for damage or deformation to the weight and/or weight bracket with corrective action as necessary. Since we issued AD 2011-27-51, a secondary elevator bob-weight stop bolt has been designed. This proposed AD would require installation of the secondary elevator bob- weight stop bolt. The elevator bob-weight (stabilizer weight) traveling past its stop bolt may allow the attaching linkage to move over-center and lead to reduced nose down elevator control, which could result in loss of control. We are proposing this AD to correct the unsafe condition on these products.
Airworthiness Directives; Pilatus Aircraft Ltd. Airplanes
We propose to adopt a new airworthiness directive (AD) for Pilatus Aircraft Ltd. Model PC-12/47E airplanes. This proposed AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as common grounding of both the pilot Primary Flight Display (PFD) and the Electronic Standby Instrument System (ESIS). If the common ground fails both navigations systems could fail simultaneously, which could result in loss of control. We are issuing this proposed AD to require actions to address the unsafe condition on these products.
Airworthiness Directives; the Boeing Company Airplanes
We propose to adopt a new airworthiness directive (AD) for certain the Boeing Company Model 777-200 series airplanes. This proposed AD was prompted by reports of smoke or flames in the passenger cabin of various transport category airplanes, related to the wiring for the passenger cabin in-flight entertainment (IFE) system, cabin lighting, and passenger seats. This proposed AD would require, for certain airplanes, doing an inspection of the electrical power control panel for a certain part number, and corrective action if necessary; and for certain other airplanes, installing a new electrical power control panel, and making changes to the wiring and certain electrical load management system (ELMS) panels. We are proposing this AD to ensure that the flightcrew is able to turn off electrical power to the IFE systems and other non-essential electrical systems through a switch in the flight compartment in the event of smoke or flames. In the event of smoke or flames in the airplane flight deck or passenger cabin, the flightcrew's inability to turn off electrical power to the IFE system and other non-essential electrical systems could result in the inability to control smoke or flames in the airplane flight deck or passenger cabin during a non-normal or emergency situation, and consequent loss of control of the airplane.
Airworthiness Directives; The Boeing Company Airplanes
We propose to adopt a new airworthiness directive (AD) for certain The Boeing Company Model 727 airplanes. This proposed AD is intended to complete certain mandated programs intended to support the airplane reaching its limit of validity (LOV) of the engineering data that support the established structural maintenance program. For certain airplanes, this proposed AD would require modification of the web of the horizontal stabilizer center section rear spar. For the other airplanes, this proposed AD would require an inspection for cracks in the web, and repair or modification as applicable. We are proposing this AD to prevent cracking at the upper fastener holes in the riveted web in the horizontal stabilizer center section rear spar, which could result in failure of the spar forging and lead to horizontal stabilizer separation and loss of control of the airplane.
Airworthiness Directives; Austro Engine GmbH Engines
We are adopting a new airworthiness directive (AD) for all Austro Engine GmbH model E4 engines. This AD requires removing from service certain part number waste gate controllers. This AD was prompted by several reports of power loss events due to fracture of the waste gate controller lever. We are issuing this AD to prevent engine power loss or in-flight shutdown, which could result in loss of control and damage to the airplane.