AD 2019-22-05

This AD is effective December 23, 2019.

The Director of the Federal Register approved the incorporation by reference of a certain publication listed in this AD as of December 23, 2019.

For service information identified in this final rule, contact General Electric Company, GE-Aviation, Room 285, 1 Neumann Way, Cincinnati, OH 45215, phone: 513-552-3272; fax: 513-552-3329; email: geae.aoc@ge.com. You may view this service information at the FAA, Engine and Propeller Standards Branch, 1200 District Avenue, Burlington, MA 01803. For information on the availability of this material at the FAA, call 781-238-7759. It is also available on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2019-0394.

Michael Richardson-Bach, Aerospace Engineer, ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803; phone: 781-238-7747; fax: 781-238-7199; email: michael.richardson-bach@faa.gov.

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to supersede AD 2017-23-06, Amendment 39-19100 (82 FR 52830, November 15, 2017), (“AD 2017-23-06”). AD 2017-23-06 applied to certain GE CF34-8C1, CF34-8C5, CF34-8C5A1, and CF34-8C5B1 engines. The NPRM published in the Federal Register on June 28, 2019 (84 FR 30956). The NPRM was prompted by multiple engine fires that have occurred as a result of malfunctions related to the OBV. The NPRM proposed to require repetitive inspections of the OBV fuel tubes, OBV bleed air manifold link rod assemblies, and the OBV fuel fittings and replacement of OBVs or related hardware that fail inspection. In addition, the NPRM proposed to expand the applicability of these inspections to include additional GE CF34-8C model turbofan engines. The FAA is issuing this AD to address the unsafe condition on these products.

The FAA gave the public the opportunity to participate in developing this AD. The following presents the comments received on the NPRM and the FAA's response to each comment.

GE requested that the FAA extend the initial and repetitive inspection intervals to 16,000 flight hours (FHs) and 1,680 FHs, respectively, for engines equipped with OBV part number (P/N) 4123T71P05. GE reasoned that based on testing and analysis, OBV P/N 4123T71P05 is more resistant to wear than OBV P/N 4123T71P04, and earlier versions, if the installation support links are regularly inspected and maintained.

The FAA disagrees with extending the inspection intervals for engines equipped with OBV P/N 4123T71P05 because the FAA did not find GE's test and analysis data sufficient to justify the extended inspection intervals. The FAA did not change this AD.

The National Transportation Safety Board (NTSB) supported this AD and requested that the FAA consider similar rulemaking to include the GE CF34-8E model turbofan engines. The NTSB suggested that the unsafe condition exists on this engine and that the FAA should identify the higher-risk OBVs and publish an AD that mandates a repetitive inspection for the GE CF34-8E OBVs.

The FAA agrees to consider future rulemaking for the GE CF34-8E model turbofan engines because those engines have experienced the same unsafe condition addressed by the engine models of this AD. The FAA did not change this AD.

The Air Line Pilots Association International and an individual commenter expressed support for the AD as written.

The FAA reviewed the relevant data, considered the comments received, and determined that air safety and the public interest require adopting this AD as proposed except for minor editorial changes. The FAA has determined that these minor changes:

• Are consistent with the intent that was proposed in the NPRM for addressing the unsafe condition; and

• Do not add any additional burden upon the public than was already proposed in the NPRM.

The FAA reviewed GE Service Bulletin (SB) CF34-8C S/B 75-0020, R04, dated May 10, 2019. The SB describes procedures for inspecting the bleed air manifold link rod assemblies; the supply, return, and drain fuel fittings; and the fuel tubes on the OBV. This service information is reasonably available because the interested parties have access to it through their normal course of business or by the means identified in the ADDRESSES section.

The FAA estimates that this AD affects 1,297 engines installed on airplanes of U.S. registry.

The FAA estimates the following costs to comply with this AD:

The FAA estimates the following costs to do any necessary replacements that would be required based on the results of the inspection. The FAA has no way of determining the number of aircraft that might need these replacements:

Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, Section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the Agency's authority.

The FAA is issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701, “General requirements.” Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.

This AD is issued in accordance with authority delegated by the Executive Director, Aircraft Certification Service, as authorized by FAA Order 8000.51C. In accordance with that order, issuance of ADs is normally a function of the Compliance and Airworthiness Division, but during this transition period, the Executive Director has delegated the authority to issue ADs applicable to engines, propellers, and associated appliances to the Manager, Engine and Propeller Standards Branch, Policy and Innovation Division.

The FAA has determined that this AD will not have federalism implications under Executive Order 13132. This AD will not have a substantial direct effect on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government.

For the reasons discussed above, I certify that this AD:

(1) Is not a “significant regulatory action” under Executive Order 12866,

(2) Will not affect intrastate aviation in Alaska, and

(3) Will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act.

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows:

1. The authority citation for part 39 continues to read as follows:

2. The FAA amends § 39.13 by removing Airworthiness Directive (AD) 2017-23-06, Amendment 39-19100 (82 FR 52830, November 15, 2017), and adding the following new AD: