AD 2021-05-10 Requires Repetitive Functional Tests Of The APU Fuel Feed Line Shroud

The FAA is adopting a new airworthiness directive (AD) for certain Airbus Canada Limited Partnership Model BD-500-1A10 and BD-500-1A11 airplanes.

This AD was prompted by a report that threaded fuel couplings were incorrectly installed at final assembly and in service. This AD requires repetitive functional tests of the auxiliary power unit (APU) fuel feed line shroud, a general visual inspection of the APU fuel feed line shroud for any loose couplings; and tightening any loose couplings, which would terminate the repetitive functional tests. The FAA is issuing this AD to address the unsafe condition on these products. This AD is effective April 26, 2021.

Supplementary Information: Transport Canada Civil Aviation (TCCA), which is the aviation authority for Canada, has issued TCCA AD CF-2020-14, dated April 30, 2020 (also referred to as the Mandatory Continuing Airworthiness Information, or the MCAI), to correct an unsafe condition for certain Airbus Canada Limited Partnership Model BD-500-1A10 and BD-500-1A11 airplanes. You may examine the MCAI in the AD docket on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2020-0971.

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to certain Airbus Canada Limited Partnership Model BD-500-1A10 and BD-500-1A11 airplanes. The NPRM published in the Federal Register on October 28, 2020 (85 FR 68257). The NPRM was prompted by a report that threaded fuel couplings were incorrectly installed at final assembly and in service. The NPRM proposed to require repetitive functional tests of the APU fuel feed line shroud, a general visual inspection of the APU feed line shroud for any loose couplings; and tightening any loose couplings, which would terminate the repetitive functional tests. The FAA is issuing this AD to address loose fuel couplings, which could eventually disconnect and could lead to fuel starvation of the APU and pose a risk of fire. See the MCAI for additional background information.

FMI: www.regulations.gov