Action
Notice of proposed rulemaking (NPRM).
Summary
We propose to supersede Airworthiness Directive (AD) 81-09-09, which applies to certain Meggitt (Troy), Inc. (previously known as Stewart Warner South Wind Corporation and as Stewart Warner South Wind Division) Model Series 8240 (Models 8240-A, 8240-C, 8240E, and 8248), 8253 (Models 8253-A, 8253-B, and 8253-C), 8259 (Models 8259-A, 8259-C, 8259-DL, 8259HL2, 8259HR2, 8259JR2, 8259L, and 8259M), and 8472 (Models 8472C and 8472D) combustion heaters. AD 81-09-09 currently requires repetitive inspections of the combustion heater; repetitive general inspections of the combustion heater installation; and, for combustion heaters having 1,000 hours or more time-in-service (TIS), overhaul of the combustion heater. Since we issued AD 81-09-09, there was an airplane accident, and we received reports of the heater malfunction. This proposed AD would retain most actions from AD 81-09-09, add a calendar time to the repetitive inspections, and add more detailed actions for the general inspection. We are proposing this AD to correct the unsafe condition on these products.