AD 2021-21-04 Prompted By Reports That The Sliding Bushings In The Forward Engine Mount System Were Missing

The FAA is adopting a new airworthiness directive (AD) for certain Bombardier, Inc., Model BD-700-1A10 and BD-700-1A11 airplanes.

This AD was prompted by reports that the sliding bushings in the forward engine mount system were missing. This AD requires an inspection (gap check) of the front and aft engine mounts to verify the proper installation of the sliding bushings, and repair if necessary. The FAA is issuing this AD to address the unsafe condition on these products. This AD is effective December 8, 2021.

Supplementary Information: Transport Canada Civil Aviation (TCCA), which is the aviation authority for Canada, has  issued TCCA AD CF-2021-04, dated February 15, 2021 (also referred to as the Mandatory Continuing Airworthiness Information, or the MCAI), to correct an unsafe condition for certain Bombardier, Inc., Model BD-700-1A10 and BD-700-1A11 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-2021-0560.

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to certain Bombardier, Inc., Model BD-700-1A10 and BD-700-1A11 airplanes. The NPRM published in the Federal Register on July 9, 2021 (86 FR 36243). The NPRM was prompted by reports that the sliding bushings in the forward engine mount system were missing.

The NPRM proposed to require an inspection (gap check) of the front and aft engine mounts to verify the proper installation of the sliding bushings, and repair if necessary. The FAA is issuing this AD to address redistribution of load/stress on the mount components, which may decrease the component fatigue life; failure of the mount structural components could result in the loss of the engine attachment to the airframe. See the MCAI for additional background information.

FMI: www.regulations.gov