2021-15952. Airworthiness Directives; Gulfstream Aerospace Corporation Airplanes

AGENCY:

Federal Aviation Administration (FAA), DOT.

ACTION:

Proposed rule; withdrawal.

SUMMARY:

The FAA is withdrawing a notice of proposed rulemaking (NPRM) that proposed to adopt a new airworthiness directive (AD) for certain Gulfstream Aerospace Corporation (Gulfstream) Models G-IV and GIV-X airplanes. The NPRM was prompted by reports of disbonding and surface cracking of the composite aft pressure bulkhead. The NPRM proposed to require inspecting the forward and aft surfaces of the pressure bulkhead composite panels for damage and repairing any damage found. Since issuance of the NPRM, the FAA has determined that there is not an unsafe condition. Accordingly, the NPRM is withdrawn.

DATES:

As of July 28, 2021, the proposed rule, which published in the Federal Register on July 27, 2018 (83 FR 35568), is withdrawn.

ADDRESSES:

Examining the AD Docket

You may examine the AD docket at https://www.regulations.gov by searching for and locating Docket No. FAA-2018-0689; or in person at Docket Operations between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains this AD action, any comments received, and other information. The street address for Docket Operations is U.S. Department of Transportation, Docket Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE, Washington, DC 20590.

FOR FURTHER INFORMATION CONTACT:

William O. Herderich, Aviation Safety Engineer, Atlanta ACO Branch, FAA, 1701 Columbia Avenue, College Park, GA 30337; phone: [phone]; fax: [phone]; email: [e-mail].

SUPPLEMENTARY INFORMATION:

Background

The FAA issued an NPRM that proposed to amend 14 CFR part 39 by adding an AD that would apply to certain serial-numbered Gulfstream Models G-IV and GIV-X airplanes. The NPRM published in the Federal Register on July 27, 2018 (83 FR 35568). The NPRM was prompted by reports of disbonding and accompanying surface cracking of the composite aft pressure bulkhead. The NPRM stated that this condition, if not addressed, could result in structural failure of the aft pressure bulkhead and loss of cabin pressure.

In the NPRM, the FAA proposed to require a one-time inspection of the forward and aft surfaces of the pressure bulkhead composite panels for damage and repairing any damage found.

Actions Since the NPRM Was Issued

After issuance of the NPRM, the FAA reviewed a Gulfstream safety assessment and determined that a bulkhead with disbonding is still capable of carrying operational loads. If the affected airplanes are capable of carrying operational loads without failure, then there is no unsafe condition.

Based on the above information, the FAA has determined that AD action is not warranted and the proposal should be withdrawn.

Comments

The FAA received comments from Gulfstream, the European Union Aviation Safety Agency (EASA), and an individual commenter.

Requests

Gulfstream requested that the FAA clarify language throughout the preamble and unsafe condition statement. EASA requested the FAA add a requirement to repeat the inspection. The individual commenter requested the FAA clarify the affected serial numbers.

The FAA acknowledges these comments. However, because the NPRM is being withdrawn, the commenters' requests are no longer necessary.

Withdrawal of the NPRM constitutes only such action and does not preclude the FAA from further rulemaking on this issue, nor does it commit the FAA to any course of action in the future.

Regulatory Findings

Since this action only withdraws an NPRM, it is neither a proposed AD nor a final rule. This action, therefore, is not covered under Executive Order 12866 or the Regulatory Flexibility Act.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Incorporation by reference
• Safety

The Withdrawal

Accordingly, the notice of proposed rulemaking, which published in the Federal Register on July 27, 2018 (83 FR 35568), is withdrawn.

Issued on July 21, 2021.

Gaetano A. Sciortino,

Deputy Director for Strategic Initiatives, Compliance & Airworthiness Division, Aircraft Certification Service.