AD 2021-18-14 Requires Inspecting The Polyurethane (PU) Fuel Hoses

The FAA is adopting a new airworthiness directive (AD) for all DG Flugzeugbau GmbH Models DG-808C and DG-1000T gliders.

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 identifies the unsafe condition as damaged fuel hoses due to environmental and fatigue deterioration. This AD requires inspecting the polyurethane (PU) fuel hoses, replacing the PU fuel hoses if there is damage, and establishing a life limit for the PU fuel hoses. The FAA is issuing this AD to address the unsafe condition on these products. This AD is effective November 4, 2021.

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 all DG Flugzeugbau GmbH Models DG-808C and DG-1000T gliders. The NPRM published in the Federal Register on July 1, 2021 (86 FR 35027). The NPRM was prompted by MCAI originated by the European Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Union. EASA has issued EASA AD 2018-0127, dated June 11, 2018 (referred to after this as “the MCAI”), to address an unsafe condition on DG Flugzeugbau GmbH Models DG-808C and DG-1000T gliders.

The MCAI states:

• An occurrence was reported where, during accomplishment of a 10 years inspection on a DG-808C powered sailplane, a damaged (broken) PU [polyurethane] fuel hose was found. The result of subsequent investigation indicated that the damage mode has features of environmental and fatigue deterioration. Additionally, it was determined that similar PU fuel hoses are also installed on other powered sailplane types of the same manufacturer.
• This condition, if not detected and corrected, could lead to reduced or interrupted fuel supply to the engine, consequent loss of the available power or fire, possibly resulting in reduced control of the powered sailplane.
• To address this potential unsafe condition, DG-Flugzeugbau GmbH issued the applicable TN [Technical Note], providing instructions to inspect the affected parts and replace these with serviceable parts. Additionally, service life limits were established for those serviceable parts.
• For the reasons described above, this [EASA] AD requires repetitive inspections of the affected parts. This [EASA] AD also requires replacement of the affected parts with serviceable parts and introduces life limits for serviceable parts.

You may examine the MCAI in the AD docket at https://www.regulations.gov by searching for and locating Docket No. FAA-2021-0212.

FMI: www.regulations.gov