AD 2020-20-08 Prohibits The Installation Of A Jettisonable Cabin Window Unless The Applicable Requirements Are Accomplished

The FAA is adopting a new airworthiness directive (AD) for Airbus Helicopters Model AS332C, AS332C1, AS332L, AS332L1, AS332L2, and EC225LP helicopters.

This AD requires, depending on helicopter configuration, installing skived polytetrafluoroethylene tape (PTFE tape) or removing PTFE tape and replacing window seals. This AD also prohibits the installation of a jettisonable cabin window unless the applicable requirements are accomplished. This AD was prompted by a report of excessive friction between the window seal and the helicopter airframe. The actions of this AD are intended to address an unsafe condition on these products. This AD is effective December 11, 2020.

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 Airbus Helicopters Model AS332C, AS332C1, AS332L, AS332L1, AS332L2, and EC225LP helicopters. The NPRM published in the Federal Register on January 6, 2020 (85 FR 469). For all of the specified helicopter models without Modification (MOD) 332P087140.00 installed, the NPRM proposed to require installing PTFE tape to each jettisonable cabin window frame. For some of the specified helicopter models with MOD 332P087140.00 installed, the NPRM proposed to require removing the PTFE tape, if installed, from each jettisonable cabin window and replacing each VIP jettisonable cabin window polychloroprene seal with a silicone seal. The NPRM also proposed to prohibit the installation of a jettisonable cabin window unless the applicable required actions were accomplished.

The NPRM was prompted by EASA AD No. 2018-0039, dated February 9, 2018, and corrected March 7, 2018 (EASA AD 2018-0039), issued by EASA, which is the Technical Agent for the Member States of the European Union, to correct an unsafe condition for Airbus Helicopters (formerly Eurocopter, Eurocopter France, Aerospatiale) Model AS 332 C, AS 332 C1, AS 332 L, AS 332 L1, AS 332 L2, and EC 225 LP helicopters. EASA advises of an emergency exit window that required excessive pushing force to jettison. According to EASA, an investigation revealed the window seal was in good condition with no indication of paint contamination or of hardening. EASA advises that the root cause of the incident was excessive friction between the window seal and the airframe. EASA further advises that helicopters with VIP jettisonable cabin windows, which corresponds to MOD 332P087140.00, with PTFE skived film installed, require greater force to jettison than standard jettisonable cabin windows with PTFE skived film installed due to the thickness of the VIP jettisonable cabin windows.

EASA states if this condition is not corrected, it could prevent the window from jettisoning, subsequently affecting the evacuation of passengers during an emergency situation. To address this unsafe condition, EASA AD 2018-0039 requires installing PTFE skived film on the window frames of helicopters with standard jettisonable cabin windows, and removing PTFE skived film and replacing polychloroprene seals with silicone seals on the window frames of helicopters with VIP jettisonable cabin windows.

FMI: www.regulations.gov