Proposed rule · 2026-22919

Airworthiness Directives; Airbus Canada Limited Partnership (Type Certificate Previously Held by C Series Aircraft Limited Partnership (CSALP); Bombardier, Inc.) Airplanes

The FAA proposes to supersede Airworthiness Directive (AD) 2021-13-20, which applies to certain Airbus Canada Limited Partnership Model BD-500-1A10 and BD-500-1A11 airplanes. AD 2021-13-20 requires inspecting the waste box, waste access doubler, and waste service door for corrosion, and doing applicable on-condition actions. Since the FAA issued AD 2021-13-20, the FAA has determined that a full secondary fuel vapor barrier must be applied. This proposed AD would retain all requirements of AD 2021-13-20 and would also require, for certain airplanes, an additional inspection of the waste box, waste access doubler, and waste service door for corrosion, and applicable on- condition actions. The FAA is proposing this AD to address the unsafe condition on these products.