Airworthiness Directives; Meggitt (Troy), Inc. Combustion Heaters
We are revising a notice of proposed rulemaking (NPRM) for certain Meggitt (Troy), Inc. (previously known as Stewart Warner South Wind Corporation and as Stewart Warner South Wind Division) Model Series (to include all the variants) 921, 930, 937, 940, 944, 945, 977, 978, 979, 8240, 8253, 8259, and 8472 combustion heaters that proposed to supersede airworthiness directive (AD) 81-09-09. The NPRM proposed to retain most actions from AD 81-09-09, add a calendar time to the repetitive inspections, add more detailed actions to the inspections, and add a pressure decay test. The NPRM was prompted by an airplane accident and reports we received of the heater malfunctioning. This action revises the NPRM by adding combustion heater models series to the applicability and modifying the compliance times. We are proposing this SNPRM to correct the unsafe condition on these products. Since these actions impose an additional burden over that proposed in the NPRM, we are reopening the comment period to allow the public the chance to comment on these proposed changes.
Airworthiness Directives; General Electric Company Turbofan Engines
We propose to supersede airworthiness directive (AD) 2015-15- 03, which applies to all General Electric Company (GE) GEnx turbofan engine models. AD 2015-15-03 precludes the use of certain full authority digital engine control (FADEC) software on GEnx turbofan engines. Since we issued AD 2015-15-03, GE implemented final design changes that remove the unsafe condition. This proposed AD would require removing a specific part and replacing it with a part eligible for installation and specifying the FADEC software version for the affected GEnx turbofan engines. We are proposing this AD to prevent engine failure, loss of thrust control, and damage to the airplane.