Document ID: FAA-2018-0547-0004
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: Bombardier, Inc., Airplanes
Posted Date: 2019-08-28T04:00Z

[Federal Register Volume 84, Number 167 (Wednesday, August 28, 2019)]
[Proposed Rules]
[Pages 45118-45119]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-18517]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2018-0547; Product Identifier 2017-NM-091-AD]
RIN 2120-AA64

Airworthiness Directives; Bombardier, Inc., Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Proposed rule; withdrawal.

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SUMMARY: The FAA is withdrawing a notice of proposed rulemaking (NPRM) 
that proposed to adopt a new airworthiness directive (AD) that would 
have applied to certain Bombardier, Inc., Model DHC-8-400 series 
airplanes. The NPRM was prompted by reports of wear on fuel couplings, 
bonding springs, and sleeves as well as fuel tube end ferrules and fuel 
component end ferrules. The NPRM would have required repetitive 
inspections of the existing clamshell coupling bonding wires, fuel 
couplings, and associated sleeves for certain criteria, and replacement 
as necessary. The NPRM would also have required repetitive inspections 
of the fuel tube end ferrules, fuel component end ferrules, and ferrule 
o-ring flanges for damage and wear, and rework as necessary. Since 
issuance of the NPRM, the FAA determined that more restrictive 
airworthiness limitations are also necessary, that an

[[Page 45119]]

optional terminating modification is appropriate for certain airplanes, 
and that the NPRM does not adequately address the identified unsafe 
condition. Accordingly, the NPRM is withdrawn.

DATES: The FAA is withdrawing the proposed rule published July 6, 2018 
(83 FR 31488), as of August 28, 2019.

ADDRESSES: 

Examining the AD Docket

    You may examine the AD docket on the internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2018-
0547; 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, the regulatory evaluation, 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: Joseph Catanzaro, Aerospace Engineer, 
Airframe and Propulsion Section, FAA, New York ACO Branch, 1600 Stewart 
Avenue, Suite 410, Westbury, NY 11590; telephone 516-228-7366; fax 516-
794-5531; email 9-avs-nyaco-cos@faa.gov.

SUPPLEMENTARY INFORMATION:

Discussion

    The FAA issued an NPRM that proposed to amend 14 CFR part 39 by 
adding an AD that would apply to the specified products. The NPRM was 
published in the Federal Register on July 6, 2018 (83 FR 31488). The 
NPRM was prompted by reports of wear on fuel couplings, bonding 
springs, and sleeves as well as fuel tube end ferrules and fuel 
component end ferrules.
    The NPRM proposed to require repetitive inspections of the existing 
clamshell coupling bonding wires, fuel couplings, and associated 
sleeves for certain criteria, and replacement as necessary. The NPRM 
also proposed to require repetitive inspections of the fuel tube end 
ferrules, fuel component end ferrules, and ferrule o-ring flanges for 
damage and wear, and rework as necessary. The proposed actions were 
intended to address wear on fuel couplings, bonding springs, and 
sleeves as well as fuel tube end ferrules and fuel component end 
ferrules, which could reduce the integrity of the electrical bonding 
paths through the fuel line and components, and ultimately lead to fuel 
tank ignition in the event of a lightning strike.

Actions Since the NPRM Was Issued

    Since issuance of the NPRM, Bombardier developed a new optional 
terminating modification for certain Model DHC-8-400 series airplanes 
and issued associated service information. In addition, the 
applicability for certain required actions was revised and more 
restrictive airworthiness limitations related to the identified unsafe 
condition were developed. In light of these changes, the FAA is 
considering further rulemaking.
    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.

FAA's Conclusions

    Upon further consideration, the FAA has determined that the NPRM 
does not adequately address the identified unsafe condition. 
Accordingly, the NPRM is withdrawn.

Regulatory Findings

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

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

The Withdrawal

0
Accordingly, the notice of proposed rulemaking, Docket No. FAA-2018-
0547, which was published in the Federal Register on July 6, 2018 (83 
FR 31488), is withdrawn.

    Issued in Des Moines, Washington, on August 22, 2019.
Suzanne Masterson,
Acting Director, System Oversight Division, Aircraft Certification 
Service.
[FR Doc. 2019-18517 Filed 8-27-19; 8:45 am]
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