Action
Notice of proposed rulemaking (NPRM).
Summary
The FAA proposes to supersede Airworthiness Directive (AD) 99- 23-18, AD 2005-03-07, AD 2013-12-07, and AD 2014-04-07, which apply to certain Bell Helicopter Textron Canada (now Bell Textron Canada Limited) Model 407 helicopters. AD 99-23-18 requires revising the life limits for certain parts, replacing each part that has exceeded its life limit, and revising the Airworthiness Limitation Section (ALS) of the existing maintenance manual. AD 2005-03-07 requires establishing a maximum accumulated Retirement Index Number (RIN) count for certain crosstube assemblies and revising the ALS of the existing maintenance manual. AD 2013-12-07 requires inspecting the tailboom assembly for a crack, loose rivet, or other damage and depending on the inspection results, replacing certain parts. AD 2014-04-07 requires preflight checking, repetitively inspecting for a crack in certain tailbooms, modifying and re-identifying certain tailbooms, installing an improved horizontal stabilizer assembly, and revising the ALS of the existing maintenance manual. Since the FAA issued those ADs, a report was received of a crack on the tailboom lower skin due to fatigue damage and new and more restrictive airworthiness limitations have been issued. This proposed AD would require incorporating into existing maintenance records requirements (airworthiness limitations) as specified in the ALS service information. The FAA is proposing this AD to address the unsafe condition on these products.