Airworthiness Directive 2025-04320
one-timeAirworthiness Directives; Airbus Canada Limited Partnership (Type Certificate Previously Held by C Series Aircraft Limited Partnership (CSALP); Bombardier, Inc.) Airplanes
What this AD requires
The FAA is adopting a new airworthiness directive (AD) for all Airbus Canada Limited Partnership Model BD-500-1A10 and BD-500-1A11 airplanes. This AD was prompted by a design review that discovered software protection logic for potential large leaks from the engine bleed duct inside the engine core compartments was partially impaired. This AD requires revising the existing airplane flight manual (AFM) to incorporate the procedures for the flightcrew to manually isolate the opposite functional engine in the event of an engine bleed duct large leak condition, as specified in a Transport Canada AD, which is incorporated by reference (IBR). The FAA is issuing this AD to address the unsafe condition on these products.
Which aircraft AD 2025-04320 applies to
Whether AD 2025-04320 actually applies to your aircraft (by serial and installed parts) and whether it’s already complied with comes from that aircraft’s records.
How AD compliance is recorded
A valid compliance record (14 CFR 43.9) states:
Tailplate reads a tail number’s logbooks and matches every applicable AD — including this one — to its compliance evidence, with recurring next-due dates computed.
Look up a tail number →Read the full directive (Federal Register)Applicability is derived from the FAA directive corpus and is advisory, not a legal airworthiness determination. Compliance is established only from an aircraft’s actual records.