AD 2021-05-03 Requires Various Inspections Of The Left-Hand Side (LH) Engine Fuel Supply Hose

The FAA is adopting a new airworthiness directive (AD) for certain Airbus Helicopters Model EC225LP helicopters.

This AD requires various inspections of the left-hand side (LH) engine fuel supply (fuel supply) hose and depending on the inspection results, reinstalling the fuel supply hose or removing the fuel supply hose from service. Additionally, this AD requires installing an improved part and prohibits installing a certain part-numbered LH fuel supply hose on any helicopter unless it is installed by following certain procedures. This AD was prompted by a report of an incorrect installation of the LH fuel supply hose causing restricted fuel flow to the LH engine. The FAA is issuing this AD to address the unsafe condition on these products. This AD is effective January 27, 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 Airbus Helicopters Model EC225LP helicopters with a LH fuel supply hose part number (P/N) 704A34416087 installed. The NPRM published in the Federal Register on October 7, 2020 (85 FR 63235, October 7, 2020). For helicopters delivered to the first operator before November 30, 2018, and for helicopters delivered to the first operator on or after November 30, 2018, that have had the LH fuel supply hose replaced or reinstalled before May 10, 2019, the NPRM proposed to require visually inspecting the LH fuel supply hose for twisting, and if needed, borescope inspecting the entire length of the inside of the fuel supply hose for twisting. Depending on the inspection results, the NPRM proposed to require reinstalling or removing the fuel supply hose from service.

Additionally, the NPRM proposed to prohibit installing a certain part-numbered LH fuel supply hose on any helicopter unless that LH fuel supply hose is installed by following certain procedures specified in the manufacturer's service bulletin. The proposed requirements were intended to prevent a decrease of the LH engine power when accelerating to a power setting corresponding to One Engine Inoperative (OEI) power and subsequent reduced control of the helicopter.

The NPRM was prompted by EASA AD 2019-0092, dated April 26, 2019 (EASA AD 2019-0092), 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) Model EC 225 LP helicopters, all serial numbers. EASA advised that an occurrence was reported where during an inflight single engine power check, the LH side engine experienced a power loss. EASA stated that a subsequent investigation determined that the fuel flow to the affected engine was restricted by a twisted fuel supply hose. EASA stated that this condition, if not detected and corrected, could lead to a decrease of the LH engine power when accelerating to the power setting corresponding to OEI power, and subsequent reduced control of the helicopter. Accordingly, EASA AD 2019-0092 required a one-time visual inspection of the fuel supply hose and depending on the inspection results, removing from service or replacing the affected part. EASA AD 2019-0092 also introduced reinstallation requirements for a fuel supply hose that is being replaced or reinstalled.

After the FAA issued the NPRM, the FAA issued a supplemental notice of proposed rulemaking (SNPRM) to amend 14 CFR part 39 by adding an AD that would apply to Airbus Helicopters Model EC225LP helicopters with a LH fuel supply hose P/N 704A34416087 installed. The SNPRM published in the Federal Register on May 10, 2021 (86 FR 24783, May 10, 2021) (the May 2021 SNPRM). The May 2021 SNPRM proposed to require visually inspecting the LH fuel supply hose P/N 704A34416087 for twisting, and if needed, borescope inspecting the entire length of the inside of the fuel supply hose for twisting. Depending on the inspection results, the May 2021 SNPRM proposed to require reinstalling or removing the fuel supply hose from service. Additionally, the May 2021 SNPRM proposed to prohibit installing a certain part-numbered LH fuel supply hose on any helicopter unless that LH fuel supply hose is installed by following certain procedures specified in the manufacturer's service bulletin.

The May 2021 SNPRM was prompted by the FAA's determination that operators may not have the information required to comply with the proposed requirements in the NPRM. Operators may not know the date the helicopter was delivered to the first operator. Additionally, operators may not know whether the LH fuel supply hose has been previously removed or reinstalled since the maintenance regulations do not require certain operators to maintain these records after one year.

Accordingly, the FAA determined that revising proposed paragraph (e)(1) of the NPRM by deleting the language referring to delivery dates and dates of LH fuel supply hose replacement or reinstallation was necessary. As a result of these changes, the FAA revised the NPRM to specify that all helicopters included in the applicability paragraph would be required to comply with the proposed requirements in the May 2021 SNPRM. Also, after the NPRM was issued, the FAA determined that a limit on special flight permits was required. The May 2021 SNPRM reflected this change and stated that special flight permits may be permitted provided that there are no passengers on board.

Since the May 2021 SNPRM was issued, EASA issued EASA AD 2021-0156, dated July 2, 2021 (EASA AD 2021-0156), which supersedes EASA AD 2019-0092. EASA advises that Airbus Helicopters has developed an improved fuel supply hose P/N 704A34416101 and modification instructions to install the improved part. Accordingly, EASA AD 2021-0156 retains the requirements of EASA AD 2019-0092 and requires replacing the affected part with the improved part. EASA AD 2021-0156 also allows a terminating action for the inspection requirements once the improved part has been installed according to the installation requirements.

Accordingly, the FAA issued a second SNPRM to amend 14 CFR part 39 by adding an AD that would apply to Airbus Helicopters Model EC225LP helicopters with a LH fuel supply hose P/N 704A34416087 installed. This SNPRM published in the Federal Register on September 7, 2021 (86 FR 49937, September 7, 2021) (the September 2021 SNPRM). The September 2021 SNPRM proposed to require visually inspecting the LH fuel supply hose for twisting, and if needed, borescope inspecting the entire length of the inside of the fuel supply hose for twisting. Depending on the inspection results, the September 2021 SNPRM proposed to require reinstalling or removing the fuel supply hose from service.

Additionally, the September 2021 SNPRM proposed to prohibit installing a certain partnumbered LH fuel supply hose on  any helicopter unless that LH fuel supply hose is installed by following certain procedures described in the manufacturer's service bulletin. Finally, the September 2021 SNPRM proposed to require modifying your helicopter by removing from service LH fuel supply hose P/N 704A34416087 and installing the improved LH fuel supply hose P/N 704A34416101. This modification would provide terminating action for the proposed inspection requirements of the September 2021 SNPRM.

FMI: www.regulations.gov