AD 2021-26-21 Describes The Unsafe Condition As Insufficient Performance Of The Fuel Drain System

The FAA is adopting a new airworthiness directive (AD) for certain Pilatus Aircraft Ltd. (Pilatus) Model PC-24 airplanes.

This AD was prompted by mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as insufficient performance of the fuel drain system that could lead to fire and damage of the airplane. This AD requires modifying the fuel drain pipe routing and installing a drain mast. The FAA is issuing this AD to address the unsafe condition on these products. This AD is effective February 25, 2022.

Supplementary Information: The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 by adding an AD that would apply to certain serial-numbered Pilatus Model PC-24 airplanes. The NPRM published in the Federal Register on October 8, 2021 (86 FR 56227). The NPRM was based on MCAI from the European Union Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Union. EASA issued AD 2020-0252, dated November 12, 2020 (referred to after this as “the MCAI”) to address the unsafe condition on these products.

The MCAI states:

• An occurrence was reported where an insufficient performance of the fuel drain system was detected on certain PC-24 aeroplanes.
• This condition, if not corrected, could lead, in case of a fuel leak, to contamination of the inboard rear fuselage, creating a fuel vapour which, in combination with an ignition source, could possibly result in a fire and consequent damage to the aeroplane.
• To address this potential unsafe condition, Pilatus Aircraft issued the [service bulletin] SB providing instructions to modify the fuel drain pipe routing and to install a drain mast.
• For the reason described above, this [EASA] AD requires modification of the fuel drain system.

In the NPRM, the FAA proposed to require modifying the fuel drain pipe routing and installing a drain mast. The FAA is issuing this AD to address the unsafe condition on these products.

You may examine the MCAI in the AD docket at https://www.regulations.gov by searching for and locating Docket No. FAA-2021-0218.

FMI: www.regulations.gov