AD Amdt-39-9346

Recurring final rule

Airworthiness Directives; General Electric Company CF6 Series Turbofan Engines

AD Number
Amdt-39-9346
Status
final_rule
Effective Date
Product Category
engine
Docket
Docket No. 95-ANE-10
FR Citation
60 FR 46758
Technical illustration of an aircraft turbine engine assembly
Problem area Engine

Applicability

TypeManufacturerModelDetails
engine General Electric Company CF6 Series Airworthiness Directives; General Electric Company CF6 Series Turbofan Engines

Unsafe Condition

Cracked side links in the five-link forward mount assembly could fracture, leading to failure of the second side link, forward engine mount pylon attachment bolts, and possible engine separation.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Perform initial and repetitive on-wing visual inspections of side links for cracks. Replace cracked side links and pylon attachment bolts. Inspect fail-safe bolt and platform lug if cracks are found. Conduct shop-level refurbishment of side links as a terminating action.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Before further flight

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

General Electric Company CF6-45/-50 series turbofan engines

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

This amendment adopts a new airworthiness directive (AD), applicable to General Electric Company (GE) CF6-45/-50 series turbofan engines, that requires an initial and repetitive on-wing visual inspection of the side links of the five-link forward mount assembly for cracks, and replacement of the side links and pylon attachment bolts, and inspection of the fail-safe bolt and platform lug, if the side links are found cracked. This AD also requires a shop-level refurbishment of the side links as a terminating action to the on-wing inspection program. This amendment is prompted by four reports of cracked side links detected during routine engine shop visits. The actions specified by this AD are intended to prevent a side link fracture, which could result in the failure of the second side link, or the forward engine mount pylon attachment bolts, and possible separation of the engine from the aircraft.

Document Text

Show stored source text (verify against official source)
[Federal Register Volume 60, Number 174 (Friday, September 8, 1995)]
[Rules and Regulations]
[Pages 46758-46760]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 95-20849]



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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 95-ANE-10; Amendment 39-9346; AD 95-17-15]


Airworthiness Directives; General Electric Company CF6 Series 
Turbofan Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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

SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to General Electric Company (GE) CF6-45/-50 series turbofan 
engines, that requires an initial and repetitive on-wing visual 
inspection of the side links of the five-link forward mount assembly 
for cracks, and replacement of the side links and pylon attachment 
bolts, and inspection of the fail-safe bolt and platform lug, if the 
side links are found cracked. This AD also requires a shop-level 
refurbishment of the side links as a terminating action to the on-wing 
inspection program. This amendment is prompted by four reports of 
cracked side links detected during routine engine shop visits. The 
actions specified by this AD are intended to prevent a side link 
fracture, which could result in the failure of the second side link, or 
the forward engine mount pylon attachment bolts, and possible 
separation of the engine from the aircraft.

DATES: Effective October 10, 1995.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of October 10, 1995.

ADDRESSES: The service information referenced in this AD may be 
obtained from General Electric Aircraft Engines, CF6 Distribution 
Clerk, Room 132, 111 Merchant Street, Cincinnati, OH 45246. This 
information may be examined at the Federal Aviation Administration 
(FAA), New England Region, Office of the Assistant Chief Counsel, 12 
New England Executive Park, Burlington, MA; or at the Office of the 
Federal Register, 800 North Capitol Street, NW., suite 700, Washington, 
DC.

FOR FURTHER INFORMATION CONTACT: Richard Woldan, Aerospace Engineer, 
Engine Certification Office, FAA, Engine and Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803-5299; telephone (617) 
238-7136; fax (617) 238-7199.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to include an airworthiness 
directive (AD) that is applicable to General Electric Company (GE) CF6-
45/-50 series turbofan engines was published in the Federal Register on 
April 6, 1995 (60 FR 17487). That action proposed to require an initial 
and repetitive on-wing visual inspection of the side links of the five-
link forward mount assembly for cracks, and replacement of the side 
links and pylon attachment bolts, and inspection of the fail-safe bolt 
and platform lug, if side links are found cracked. That proposal also 
would require a shop-level refurbishment of the side links as a 
terminating action to the on-wing inspection program. The actions would 
be required to be accomplished in accordance with GE Aircraft Engines 
CF6-50 Service Bulletin No. 72-1092, dated November 18, 1994.
    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comment received.
    The one commenter states that the requirement to refurbish the side 
link at the next engine shop visit after effective date of the AD 
identified in paragraph (b) should be extended so that their current 
maintenance program is not disrupted. 

[[Page 46759]]

    The commenter further feels that the initial and repetitive 
inspection program will be sufficient to meet the safety objectives of 
the AD, and therefore considers the refurbishment to be optional. The 
FAA does not concur. The FAA has determined that the refurbishment 
compliance schedule fairly and reasonably balances the safety need to 
eliminate the unsafe condition from the fleet as quickly as possible 
with the operators' need to avoid unscheduled maintenance actions. The 
initial and repetitive inspections were intended as an interim 
corrective action only, and in order to meet the safety objectives of 
the AD, the refurbishment was deemed necessary. Individual operators 
who believe their circumstances warrant relief from the compliance 
schedule may submit requests for alternative methods of compliance or 
adjustments to the compliance times.
    After careful review of the available data, including the comment 
noted above, the FAA has determined that air safety and the public 
interest require the adoption of the rule as proposed.
    The FAA estimates that 220 engines installed on aircraft of U.S. 
registry will be affected by this AD, that it will take approximately 
7.5 work hours per engine to accomplish the required actions, and that 
the average labor rate is $60 per work hour. The FAA has estimated that 
only a small percentage of parts will actually require replacement as a 
result of this AD, and therefore, has determined the parts cost to be 
negligible. Based on these figures, the total cost impact of the AD on 
U.S. operators is estimated to be $99,000.
    The regulations adopted herein will not have substantial direct 
effects 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. Therefore, in 
accordance with Executive Order 12612, it is determined that this final 
rule does not have sufficient federalism implications to warrant the 
preparation of a Federalism Assessment.
    For the reasons discussed above, I certify that this action (1) is 
not a ``significant regulatory action'' under Executive Order 12866; 
(2) is not a ``significant rule'' under DOT Regulatory Policies and 
Procedures (44 FR 11034, February 26, 1979); 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. A final evaluation has been prepared for this action 
and it is contained in the Rules Docket. A copy of it may be obtained 
from the Rules Docket at the location provided under the caption 
ADDRESSES.

List of Subjects in 14 CFR Part 39

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

Adoption of the Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends part 39 of 
the Federal Aviation Regulations (14 CFR part 39) as follows:

PART 39--AIRWORTHINESS DIRECTIVES

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

    Authority: 49 USC 106(g), 40101, 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by adding the following new 
airworthiness directive:

95-17-15 General Electric Company: Amendment 39-9346. Docket 95-ANE-
10.

    Applicability: General Electric Company (GE) CF6-45/-50 series 
turbofan engines installed on, but not limited to, Airbus A300 
series, Boeing 747 series, and McDonnell Douglas DC-10 series 
aircraft.

    Note: This airworthiness directive (AD) applies to each engine 
identified in the preceding applicability provision, regardless of 
whether it has been modified, altered, or repaired in the area 
subject to the requirements of this AD. For engines that have been 
modified, altered, or repaired so that the performance of the 
requirements of this AD is affected, the owner/operator must use the 
authority provided in paragraph (d) to request approval from the 
Federal Aviation Administration (FAA). This approval may address 
either no action, if the current configuration eliminates the unsafe 
condition, or different actions necessary to address the unsafe 
condition described in this AD. Such a request should include an 
assessment of the effect of the changed configuration on the unsafe 
condition addressed by this AD. In no case does the presence of any 
modification, alteration, or repair remove any engine from the 
applicability of this AD.

    Compliance: Required as indicated, unless accomplished 
previously. To prevent a side link fracture, which could result in 
failure of the second side link, or the forward engine mount pylon 
attachment bolts, and possible separation of the engine from the 
aircraft, accomplish the following:
    (a) Inspect left-hand side links, Part Numbers (P/N) 9204M94P01, 
9204M94P03, and 9346M99P01, and right-hand side links, P/N's 
9204M94P02, 9204M94P04, and 9346M99P02, that have not had the side 
link refurbishment done in accordance with GE CF6-50 Task Numbered 
Shop Manual, GEK 50481, Chapter 72-23-11, including Temporary 
Revision No. 72-0821 and 72-0822, both dated November 1, 1994, as 
follows:
    (1) For side links that have not been previously inspected in 
accordance with GE Aircraft Engines (GEAE) CF6-50 Service Bulletin 
(SB) No. 72-1092, dated November 18, 1994, inspect in accordance 
with paragraph 2.A of GEAE CF6-50 SB No. 72-1092, dated November 18, 
1994, prior to accumulating 350 cycles in service (CIS), or 750 
hours time in service (TIS), after the effective date of this AD, 
whichever occurs earlier.
    (2) For side links that have been previously inspected in 
accordance with GEAE CF6-50 SB No. 72-1092, dated November 18, 1994, 
inspect in accordance with paragraph 2.A of GEAE CF6-50 SB No. 72-
1092, dated November 18, 1994, prior to accumulating 350 CIS, or 750 
hours TIS since inspected in accordance with GEAE CF6-50 SB No. 72-
1092, dated November 18, 1994, whichever occurs earlier.
    (3) Thereafter, inspect in accordance with paragraph 2.A of GEAE 
CF6-50 SB No. 72-1092, dated November 18, 1994, at intervals not to 
exceed 350 CIS, or 750 hours TIS since the last inspection, 
whichever occurs earlier.
    (4) If side links are found cracked, replace the cracked side 
links and pylon attachment bolts with serviceable parts, and inspect 
the fail-safe bolt and platform lug in accordance with paragraph 2.B 
of GEAE CF6-50 SB No. 72-1092, dated November 18, 1994, prior to 
further flight.
    (b) Refurbish the left-hand and right-hand side links identified 
in paragraph (a) of this AD at the next engine shop visit after the 
effective date of this AD in accordance with paragraph 2.C of GEAE 
CF6-50 SB No. 72-1092, dated November 18, 1994. Refurbishment of 
side links in accordance with this paragraph constitutes terminating 
action to the on-wing inspection requirements of paragraph (a) of 
this AD.
    (c) For the purpose of this AD, an engine shop visit is defined 
as the induction of an engine into a shop for maintenance involving 
the separation of the fan and core modules.
    (d) An alternative method of compliance or adjustment of the 
compliance time that provides an acceptable level of safety may be 
used if approved by the Manager, Engine Certification Office. The 
request should be forwarded through an appropriate FAA Principal 
Maintenance Inspector, who may add comments and then send it to the 
Manager, Engine Certification Office.

    Note: Information concerning the existence of approved 
alternative methods of compliance with this airworthiness directive, 
if any, may be obtained from the Engine Certification Office.

    (e) The actions required by this AD shall be done in accordance 
with the following service bulletin:

------------------------------------------------------------------------
               Document No.                 Pages           Date        
------------------------------------------------------------------------
GEAE CF6-50 SB No. 72-1092...............      1-7  Nov. 18, 1994.      
------------------------------------------------------------------------

 
[[Page 46760]]

    Total Pages: 7.
    This incorporation by reference was approved by the Director of 
the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR 
part 51. Copies may be obtained from General Electric Aircraft 
Engines, CF6 Distribution Clerk, Room 132, 111 Merchant Street, 
Cincinnati, OH 45246. Copies may be inspected at the FAA, New 
England Region, Office of the Assistant Chief Counsel, 12 New 
England Executive Park, Burlington, MA; or at the Office of the 
Federal Register, 800 North Capitol Street NW., suite 700, 
Washington, DC.
    (f) This amendment becomes effective on October 10, 1995.

    Issued in Burlington, Massachusetts, on August 15, 1995.
Jay J. Pardee,
Manager, Engine and Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 95-20849 Filed 9-7-95; 8:45 am]
BILLING CODE 4910-13-U

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