Document ID: FAA-2019-0766-0001
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: General Electric Company Turbofan Engines
Posted Date: 2019-12-03T05:00Z

[Federal Register Volume 84, Number 232 (Tuesday, December 3, 2019)]
[Proposed Rules]
[Pages 66082-66084]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-25987]

-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2019-0766; Product Identifier 2019-NE-23-AD]
RIN 2120-AA64

Airworthiness Directives; General Electric Company Turbofan 
Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

-----------------------------------------------------------------------

SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for all General Electric Company (GE) CF34-8C1, CF34-8C5, CF34-8C5A1, 
CF34-8C5B1, CF34-8C5A2, CF34-8C5A3, CF34-8E2, CF34-8E2A1, CF34-8E5, 
CF34-8E5A1, CF34-8E5A2, CF34-8E6, and CF34-8E6A1 turbofan engine 
models. This proposed AD was prompted by a predicted reduction in the 
cyclic life of the combustion chamber assembly aft flange, which could 
result in certain combustion chamber assemblies failing before reaching 
their published life limit. This proposed AD would require revisions to 
the Airworthiness Limitations Section (ALS) of the manufacturer's 
Instructions for Continued Airworthiness (ICA) and to the air carrier's 
approved Continued Airworthiness Maintenance Programs (CAMP) to 
incorporate initial and repetitive fluorescent penetrant inspections 
(FPIs) of the combustion chamber assembly. The FAA is proposing this AD 
to address the unsafe condition on these products.

DATES: The FAA must receive comments on this proposed AD by January 17, 
2020.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
     Federal eRulemaking Portal: Go to https://www.regulations.gov. Follow the instructions for submitting comments.
     Fax: 202-493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE, Washington, DC 20590.
     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    For service information identified in this NPRM, contact General 
Electric Company, GE Aviation, Room 285, 1 Neumann Way, Cincinnati, OH 
45215; phone: 513-552-3272; email: aviation.fleetsupport@ge.com. You 
may view this service information at the FAA, Engine and Propeller 
Standards Branch, 1200 District Avenue, Burlington, MA. For information 
on the availability of this material at the FAA, call 781-238-7759.

Examining the AD Docket

    You may examine the AD docket on the internet at https://www.regulations.gov by searching for and locating Docket No. FAA-2019-
0766; 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 NPRM, the regulatory evaluation, any comments received, and other 
information. The street address for Docket Operations is listed above. 
Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: David Bethka, Aerospace Engineer, ECO 
Branch, FAA, 1200 District Avenue, Burlington, MA 01803; phone: 781-
238-7129; fax: 781-238-7199; email: david.bethka@faa.gov.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    The FAA invites you to send any written relevant data, views, or 
arguments about this proposal. Send your comments to an address listed 
under the ADDRESSES section. Include ``Docket No. FAA-2019-0766; 
Product Identifier 2019-NE-23-AD'' at the beginning of your comments. 
The FAA specifically invites comments on the overall regulatory, 
economic, environmental, and energy aspects of this NPRM. The FAA will 
consider all comments received by the closing date and may amend this 
NPRM because of those comments.
    The FAA will post all comments received, without change, to https://www.regulations.gov, including any personal information you provide. 
The FAA will also post a report summarizing each substantive verbal 
contact it receives about this NPRM.

Discussion

    The FAA was notified by the manufacturer that they found a 
reduction in the cyclic life of the combustion chamber assembly when 
updating their life analysis. As a result, the manufacturer added a 
scheduled maintenance check. This condition, if not addressed, could 
result in combustion chamber assemblies failing before reaching their 
published life limit.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed GE CF34-8E Engine Manual Temporary Revision (TR) 
05-0085, dated February 21, 2019; GE CF34-8C TR 05-0141, dated February 
21, 2019; and GE CF34-8C TR 05-143, dated February 13, 2019. These TRs, 
differentiated by GE CF34-8 turbofan engine model, identify the 
combustion chamber assembly part number, life limit cycles, and new 
inspections.
    The FAA also reviewed GE CF34-8E TR 05-0086, dated February 13, 
2019, and GE CF34-8C TR 05-0142, dated February 13, 2019. These TRs, 
differentiated by GE CF34-8 turbofan engine model, describe new 
inspection threshold limits and re-inspection interval limits for the 
combustion chamber assembly.
    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.

FAA's Determination

    The FAA is proposing this AD because it evaluated all the relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other products of the same type design.

Proposed AD Requirements

    This proposed AD would require revisions to the ALS of the 
manufacturer's ICA and the air carrier's approved CAMP to incorporate 
initial

[[Page 66083]]

and repetitive FPIs of the combustion chamber assembly.

Costs of Compliance

    The FAA estimates that this proposed AD affects 1,216 GE CF34-8C 
turbofan engine models and 638 GE CF34-8E turbofan engine models 
installed on airplanes of U.S. registry.
    The FAA estimates the following costs to comply with this proposed 
AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
                Action                         Labor cost           Parts cost        product        operators
----------------------------------------------------------------------------------------------------------------
Revise the ALS and CAMP (GE CF34-8C     1 work-hour x $85 per                 $0             $85        $157,590
 and CF34-8E).                           hour = $85.
FPI combustion chamber assembly (GE     6 work-hours x $85 per                 0             510         620,160
 CF34-8C).                               hour = $510.
FPI combustion chamber assembly (GE     5 work-hours x $85 per                 0             425         271,150
 CF34-8E).                               hour = $425.
----------------------------------------------------------------------------------------------------------------

Authority for This Rulemaking

    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.

Regulatory Findings

    The FAA determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would 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 this proposed 
regulation:
    (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.

List of Subjects in 14 CFR Part 39

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

The Proposed Amendment

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

PART 39--AIRWORTHINESS DIRECTIVES

0
1. The authority citation for part 39 continues to read as follows:

    Authority:  49 U.S.C. 106(g), 40113, 44701.

Sec.  39.13   [Amended]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness 
directive (AD):

General Electric Company: Docket No. FAA-2019-0766; Product 
Identifier 2019-NE-23-AD.

(a) Comments Due Date

    The FAA must receive comments by January 17, 2020.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all General Electric Company (GE) CF34-8C1, 
CF34-8C5, CF34-8C5A1, CF34-8C5B1, CF34-8C5A2, CF34-8C5A3, CF34-8E2, 
CF34-8E2A1, CF34-8E5, CF34-8E5A1, CF34-8E5A2, CF34-8E6, and CF34-
8E6A1 turbofan engine models, including engine models marked on 
engine data plate as CF34-8C5/B, CF34-8C5/M, CF34-8C5A1/B, CF34-
8C5A1/M, CF34-8C5B1/B, CF34-8C5A2/B, and CF34-8C5A2/M.

(d) Subject

    Joint Aircraft System Component (JASC) Code 7240, Turbine Engine 
Combustion Section.

(e) Unsafe Condition

    This AD was prompted by a predicted reduction in the cyclic life 
of the combustion chamber assembly aft flange. The FAA is issuing 
this AD to prevent failure of the combustion chamber assembly. The 
unsafe condition, if not addressed, could result in combustion 
chamber assemblies failing before reaching their published life 
limit, uncontained release of the combustion chamber assembly, 
damage to the engine, and damage to the airplane.

(f) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.

(g) Required Actions

    (1) Within 90 days after the effective date of this AD, revise 
the Airworthiness Limitations Section of the GE Instructions for 
Continued Airworthiness. For air carrier operations, within 90 days 
after the effective date of this AD, also revise the approved 
continuous airworthiness maintenance program. These revisions must 
incorporate the following requirements for fluorescent penetrant 
inspections (FPI) of the combustion chamber assembly aft flange.
    (i) For a combustion chamber assembly with part number (P/N) 
4145T11G08, P/N 4145T11G09, P/N 4180T27G01, or P/N 4180T27G03 
installed on GE CF34-8E turbofan engine models, revise CF34-8E 
Engine Manual GEK112031 by:
    (A) Replacing Table 801, Static Structures--Life Limits (``Table 
801''), with the revised Table 801 in Task 05-11-05-200-801 of GE 
CF34-8E Engine Manual Temporary Revision (TR) 05-0085, dated 
February 21, 2019, and
    (B) Adding Task 05-21-03-200-801 of GE CF34-8E TR 05-0086, dated 
February 13, 2019 (``GE CF34-8E TR 05-0086'').
    (ii) For a combustion chamber assembly with P/N 4126T87G04, P/N 
4126T87G05, P/N 4126T87G07, P/N 4126T87G08, P/N

[[Page 66084]]

4180T27G04, P/N 4923T82G01, or P/N 4923T82G02 installed on GE CF34-
8C1 turbofan engine models, or with P/N 4145T11G08, P/N 4145T11G10, 
P/N 4180T27G02, P/N 4180T27G04, or P/N 4923T82G02 installed on GE 
CF34-8C5, CF34-8C5/M, CF34-8C5A1, CF34-8C5A1/M, CF34-8C5A2, CF34-
8C5A2/M, CF34-8C5A3, or CF34-8C5B1 turbofan engine models, revise 
CF34-8C Engine Manual GEK105091 by:
    (A) Replacing Table 801, (For -8C1) and Table 802 (For -8C5) 
Static Structures--Life Limits (``Table 801'' and ``Table 802''), 
with the revised Tables 801 and 802 in Task 05-11-05-200-801 of GE 
CF34-8C Engine Manual TR 05-0141, dated February 21, 2019, and
    (B) Adding Task 05-21-03-200-801 of GE CF34-8C TR 05-0142, dated 
February 13, 2019 (``GE CF34-8C TR 05-0142'').
    (iii) For a combustion chamber assembly with P/N 4145T11G08, P/N 
4145T11G10, P/N 4180T27G02, P/N 4180T27G04, or P/N 4923T82G02 
installed on GE CF34-8C5B1/B CF34-8C5/B, CF34-8C5A1/B, or CF34-
8C5A2/B turbofan engine models (Business Jet), revise CF34-8C Engine 
Manual GEK105091 by:
    (A) Replacing Table 801 (For/B -8C5 Models) Static Structures--
Life Limits with the revised Table 801 in Task 05-11-25-200-801 of 
GE CF34-8C TR 05-143, dated February 13, 2019, and
    (B) Adding Task 05-21-03-200-801 of GE CF34-8C TR 05-0142.
    (2) For any combustion chamber assembly that has exceeded the 
initial inspection threshold (in cycles) specified in GE CF34-8E TR 
05-0086 or GE CF34-8C TR 05-0142:
    (i) Perform the initial FPI of the combustion chamber assembly 
aft flange within 2,200 cycles after the effective date of this AD 
in accordance with GE CF34-8E TR 05-0086 or GE CF34-8C TR 05-0142. 
Thereafter, perform repetitive FPIs in accordance with the intervals 
in GE CF34-8E TR 05-0086 or GE CF34-8C TR 05-0142.
    (ii) If, during the FPI required by paragraph (g)(2)(i) of this 
AD, a crack is found in the combustion chamber assembly aft flange, 
disposition the assembly in accordance with paragraph 2.A. of GE 
CF34-8E TR 05-0086, or paragraph 2.A. of GE CF34-8C TR 05-0142.

(h) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, ECO Branch, FAA, has the authority to approve 
AMOCs for this AD, if requested using the procedures found in 14 CFR 
39.19. In accordance with 14 CFR 39.19, send your request to your 
principal inspector or local Flight Standards District Office, as 
appropriate. If sending information directly to the manager of the 
certification office, send it to the attention of the person 
identified in paragraph (i)(1) of this AD. You may email your 
request to: ANE-AD-AMOC@faa.gov.
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the local flight standards district office/certificate holding 
district office.

(i) Related Information

    (1) For more information about this AD, contact David Bethka, 
Aerospace Engineer, ECO Branch, FAA, 1200 District Avenue, 
Burlington, MA 01803; phone: 781-238-7129; fax: 781-238-7199; email: 
david.bethka@faa.gov.
    (2) For service information identified in this AD, contact 
General Electric Company, GE Aviation, Room 285, 1 Neumann Way, 
Cincinnati, OH 45215; phone: 513-552-3272; email: 
aviation.fleetsupport@ge.com. You may view this referenced service 
information at the FAA, Engine and Propeller Standards Branch, 1200 
District Avenue, Burlington, MA. For information on the availability 
of this material at the FAA, call 781-238-7759.

    Issued in Burlington, Massachusetts, on November 25, 2019.
Robert J. Ganley,
Manager, Engine and Propeller Standards Branch, Aircraft Certification 
Service.
[FR Doc. 2019-25987 Filed 12-2-19; 8:45 am]
 BILLING CODE 4910-13-P