Summary
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.
DATES: The comment period for the NPRM published in the Federal Register on August 20, 2014 (79 FR 49249) is reopened.