80 FR 51491 - Airworthiness Directives; The Boeing Company Airplanes

DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration

Federal Register Volume 80, Issue 164 (August 25, 2015)

We propose to adopt a new airworthiness directive (AD) for all The Boeing Company Model 777-200, -200LR, -300, and -300ER series airplanes. This proposed AD was prompted by reports of fractured forward attach fittings of the inboard flap outboard aft flap track. The fractured fittings were determined to be the result of corrosion pits forming on the inside diameter of the fittings. This proposed AD would require an inspection for the affected part number and serial number of the main flap; various additional repetitive inspections of the fitting, if necessary; and replacement of the fitting or nested bushing installation, if necessary, which would terminate the inspections. This proposed AD would also provide for optional terminating action for the repetitive inspections. We are proposing this AD to detect and correct fracture of the fitting, which could result in the loss of the inboard aft flap and could lead to a punctured fuselage, causing injury to the flightcrew and passengers, and damage to the airplane.

[Federal Register Volume 80, Number 164 (Tuesday, August 25, 2015)]
[Proposed Rules]
[Pages 51491-51495]
From the Federal Register Online  [www.thefederalregister.org]
[FR Doc No: 2015-20835]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2015-3147; Directorate Identifier 2014-NM-094-AD]
RIN 2120-AA64


Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to adopt a new airworthiness directive (AD) for all 
The Boeing Company Model 777-200, -200LR, -300, and -300ER series 
airplanes. This proposed AD was prompted by reports of fractured 
forward attach fittings of the inboard flap outboard aft flap track. 
The fractured fittings were determined to be the result of corrosion 
pits forming on the inside diameter of the fittings. This proposed AD 
would require an inspection for the affected part number and serial 
number of the main flap; various additional repetitive inspections of 
the fitting, if necessary; and replacement of the fitting or nested 
bushing installation, if necessary, which would terminate the 
inspections. This proposed AD would also provide for optional 
terminating action for the repetitive inspections. We are proposing 
this AD to detect and correct fracture of the fitting, which could 
result in the loss of the inboard aft flap and could lead to a 
punctured fuselage, causing injury to the flightcrew and passengers, 
and damage to the airplane.

[[Page 51492]]


DATES: We must receive comments on this proposed AD by October 9, 2015.

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 http://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 proposed AD, contact 
Boeing Commercial Airplanes, Attention: Data & Services Management, 
P.O. Box 3707, MC 2H-65, Seattle, WA 98124-2207; telephone 206-544-
5000, extension 1; fax 206-766-5680; Internet https://www.myboeingfleet.com. You may view this referenced service information 
at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., 
Renton, WA. For information on the availability of this material at the 
FAA, call 425-227-1221. It is also available on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2015-
3147.

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-2015-
3147; or in person at the Docket Management Facility between 9 a.m. and 
5 p.m., Monday through Friday, except Federal holidays. The AD docket 
contains this proposed AD, the regulatory evaluation, any comments 
received, and other information. The street address for the Docket 
Office (phone: 800-647-5527) is in the ADDRESSES section. Comments will 
be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: Eric Lin, Aerospace Engineer, Airframe 
Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind 
Avenue SW., Renton, WA 98057-3356; telephone: 425-917-6412; fax: 425-
917-6590; email: [email protected].

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite 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-2015-3147; 
Directorate Identifier 2014-NM-094-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed AD. We 
will consider all comments received by the closing date and may amend 
this proposed AD because of those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    We have received reports of fractured forward attach fittings of 
the inboard flap outboard aft flap track, and it is believed to be the 
result of corrosion pits forming on the inside diameter of the 
fittings. Four operators have reported finding four fractured forward 
attach fittings of the aft flap track of the inboard flap on airplanes 
with approximately 20,300 to 31,900 total flight hours and 
approximately 5,900 to 8,500 total flight cycles. In addition, two 
operators reported three cracked fittings on airplanes with 
approximately 29,300 to 35,700 total flight hours and approximately 
5,200 to 7,900 total flight cycles. This condition, if not corrected, 
could result in the loss of the inboard aft flap and could lead to a 
punctured fuselage, causing injury to the flightcrew and passengers, 
and damage to the airplane.

Related Service Information Under 1 CFR Part 51

    We reviewed Boeing Special Attention Service Bulletin 777-57-0094, 
Revision 1, dated November 5, 2014. The service information describes 
procedures for an inspection for the affected part number and serial 
number of the main flap; various additional repetitive inspections of 
the fitting, if necessary; and replacement of the fitting or nested 
bushing installation, if necessary, which would eliminate the need for 
the inspections. 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 
of this NPRM.

FAA's Determination

    We are proposing this AD because we 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 accomplishing the actions specified 
in the service information described previously, except as discussed 
under ``Differences Between this Proposed AD and the Service 
Information.'' Refer to this service information for details on the 
procedures and compliance times.

Explanation of ``RC'' Steps in Service Information

    The FAA worked in conjunction with industry, under the 
Airworthiness Directive Implementation Aviation Rulemaking Committee 
(ARC), to enhance the AD system. One enhancement was a new process for 
annotating which steps in the service information are required for 
compliance with an AD. Differentiating these steps from other tasks in 
the service information is expected to improve an owner's/operator's 
understanding of crucial AD requirements and help provide consistent 
judgment in AD compliance. The steps identified as Required for 
Compliance (RC) in any service information identified previously have a 
direct effect on detecting, preventing, resolving, or eliminating an 
identified unsafe condition.
    For service information that contains steps that are labeled as RC, 
the following provisions apply: (1) the steps labeled as RC, including 
substeps under an RC step and any figures identified in an RC step, 
must be done to comply with the AD, and an AMOC is required for any 
deviations to RC steps, including substeps and identified figures; and 
(2) steps not labeled as RC may be deviated from using accepted methods 
in accordance with the operator's maintenance or inspection program 
without obtaining approval of an AMOC, provided the RC steps, including 
substeps and identified figures, can still be done as specified, and 
the airplane can be put back in an airworthy condition.

Differences Between This Proposed AD and the Service Information

    Boeing Special Attention Service Bulletin 777-57-0094, Revision 1, 
dated November 5, 2014, specifies groups 1, 2, 3, 4, and 5 airplanes as 
the effectivity. However, this proposed AD is applicable only to groups 
1, 2, and 4 airplanes (Model 777-200, -200LR, -300, and -300ER 
airplanes) because the identified unsafe condition only affects these 
airplanes. For groups 3 and 5 airplanes (Model 777F airplanes), the

[[Page 51493]]

consequence of fitting fracture on these airplanes has not been 
determined to be an unsafe condition at this time. Therefore, we are 
not requiring inspections for groups 3 and 5 airplanes. We have 
coordinated this difference with Boeing.

Costs of Compliance

    We estimate that this proposed AD affects 148 airplanes of U.S. 
registry.
    We estimate the following costs to comply with this proposed AD:

                                                                     Estimated Costs
--------------------------------------------------------------------------------------------------------------------------------------------------------
                Action                          Labor cost          Parts cost       Cost per product                  Cost on U.S. operators
--------------------------------------------------------------------------------------------------------------------------------------------------------
Inspection to determine the part        3 work-hours x $85 per              $0  $255.....................  $37,740.
 number.                                 hour = $255.
Additional Inspections................  Up to 7 work[dash]hours x            0  Up to $595, per cycle....  Up to $88,060, per cycle.
                                         $85 per hour = $595, per
                                         cycle.
--------------------------------------------------------------------------------------------------------------------------------------------------------

    We estimate the following costs to do any necessary replacements 
that would be required based on the results of the proposed inspection. 
The nested bushing installation of the attach fitting and the fitting 
replacement are also optional terminating actions. We have no way of 
determining the number of aircraft on which these actions might be 
done.

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                       Cost per
                    Action                                    Labor cost                 Parts cost    product
----------------------------------------------------------------------------------------------------------------
Nested bushing installation of the attach       40 work-hours x $85 per hour = $3,400.          $45      $3,445.
 fitting.
Fitting replacement...........................  73 work-hours x $85 per hour = $6,205.        7,400      13,605.
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    According to the manufacturer, all of the costs of this proposed AD 
may be covered under warranty, thereby reducing the cost impact on 
affected individuals. We do not control warranty coverage for affected 
individuals. As a result, we have included all costs in our cost 
estimate.

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.
    We are 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.

Regulatory Findings

    We 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) Is not a ``significant rule'' under the DOT Regulatory Policies 
and Procedures (44 FR 11034, February 26, 1979),
    (3) Will not affect intrastate aviation in Alaska, and
    (4) 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):

The Boeing Company: Docket No. FAA-2015-3147; Directorate Identifier 
2014-NM-094-AD.

(a) Comments Due Date

    We must receive comments by October 9, 2015.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all The Boeing Company Model 777-200, -200LR, 
-300, and -300ER series airplanes, certificated in any category.

(d) Subject

    Air Transport Association (ATA) of America Code 57, Wings.

(e) Unsafe Condition

    This AD was prompted by reports of fractured forward attach 
fittings of the inboard flap outboard aft flap track. The fractured 
fittings were determined to be the result of corrosion pits forming 
on the inside diameter of the fittings. We are issuing this AD to 
detect and correct fracture of the fitting, which could result in 
the loss of the inboard aft flap and could lead to a punctured 
fuselage, causing injury to the flightcrew and passengers, and 
damage to the airplane.

[[Page 51494]]

(f) Compliance

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

(g) Inspection To Determine the Part Number

    At the applicable time specified in paragraph 1.E., 
``Compliance,'' of Boeing Special Attention Service Bulletin 777-57-
0094, Revision 1, dated November 5, 2014, except as provided by 
paragraph (l) of this AD: Do an inspection of the inboard flap of 
the main flap for affected part and serial numbers, in accordance 
with the Accomplishment Instructions of Boeing Special Attention 
Service Bulletin 777-57-0094, Revision 1, dated November 5, 2014. A 
review of airplane maintenance records is acceptable in lieu of this 
inspection if the part number and serial number of the inboard flap 
can be conclusively determined from that review.

(h) Additional Inspections

    If any inboard flap of the main flap having an affected part 
number and serial number is found during the inspection required by 
paragraph (g) of this AD: Except as provided by paragraph (l) of 
this AD, at the applicable time specified in paragraph 1.E., 
``Compliance,'' of Boeing Special Attention Service Bulletin 777-57-
0094, Revision 1, dated November 5, 2014, do the inspections 
specified in paragraph (h)(1) or (h)(2) of this AD, in accordance 
with the Accomplishment Instructions of Boeing Special Attention 
Service Bulletin 777-57-0094, Revision 1, dated November 5, 2014. 
Repeat the inspections thereafter at the applicable times specified 
in paragraph 1.E., ``Compliance,'' of Boeing Special Attention 
Service Bulletin 777-57-0094, Revision 1, dated November 5, 2014, 
until a terminating action in paragraph (k)(1), (k)(2), or (k)(3) of 
this AD is done.
    (1) At the forward attach fitting of the aft flap track of the 
inboard flap: Do a detailed inspection for cracking and bushing 
migration, and a high frequency eddy current inspection for 
cracking, in accordance with Part 2 of the Accomplishment 
Instructions of Boeing Special Attention Service Bulletin 777-57-
0094, Revision 1, dated November 5, 2014.
    (2) At the forward attach fitting of the aft flap track of the 
inboard flap: Do a detailed inspection for cracking and bushing 
migration, and an ultrasound inspection for cracking, in accordance 
with Part 3 of the Accomplishment Instructions of Boeing Special 
Attention Service Bulletin 777-57-0094, Revision 1, dated November 
5, 2014.

(i) Corrective Action for Bushing Migration

    If any bushing migration but no cracking is found during any 
inspection required by paragraph (h) of this AD: At the applicable 
times specified in paragraph 1.E., ``Compliance,'' of Boeing Special 
Attention Service Bulletin 777-57-0094, Revision 1, dated November 
5, 2014, do the actions specified in paragraphs (i)(1) through 
(i)(3) of this AD. Accomplishment of a terminating action specified 
in paragraph (i)(3) or (k) of this AD terminates the actions 
required by this paragraph.
    (1) Apply corrosion inhibiting compound BMS 3-23, Type II, 
around the bushing flanges on each side of the fitting, in 
accordance with the Accomplishment Instructions of Boeing Special 
Attention Service Bulletin 777-57-0094, Revision 1, dated November 
5, 2014. Re-apply the corrosion inhibiting compound at the time 
specified in paragraph 1.E., ``Compliance,'' of Boeing Special 
Attention Service Bulletin 777-57-0094, Revision 1, dated November 
5, 2014.
    (2) Repeat the inspections specified in paragraph (h)(1) or 
(h)(2) of this AD, except inspect for cracking only.
    (3) Do a terminating action specified in paragraph (i)(3)(i), 
(i)(3)(ii), or (i)(3)(iii) of this AD.
    (i) Install a nested bushing to the forward attach fitting of 
the aft flap track of the inboard flap, in accordance with Part 4 of 
the Accomplishment Instructions of Boeing Special Attention Service 
Bulletin 777-57-0094, Revision 1, dated November 5, 2014.
    (ii) Replace the forward attach fitting of the aft flap track of 
the inboard flap with an aluminum fitting, in accordance with Part 5 
of the Accomplishment Instructions of Boeing Special Attention 
Service Bulletin 777-57-0094, Revision 1, dated November 5, 2014.
    (iii) Replace the forward attach fitting of the aft flap track 
of the inboard flap with a titanium fitting, in accordance with Part 
6 of the Accomplishment Instructions of Boeing Special Attention 
Service Bulletin 777-57-0094, Revision 1, dated November 5, 2014.

(j) Corrective Actions for Cracking

    If any cracking is found during any inspection required by 
paragraph (h) or (i)(3) of this AD: At the applicable time specified 
in paragraph 1.E., ``Compliance,'' of Boeing Special Attention 
Service Bulletin 777-57-0094, Revision 1, dated November 5, 2014, do 
a terminating action specified in paragraph (j)(1) or (j)(2) of this 
AD. Replacement of the forward attach fitting as specified in 
paragraph (j)(1) or (j)(2) of this AD terminates the actions in this 
AD.
    (1) Replace the forward attach fitting of the aft flap track of 
the inboard flap with an aluminum fitting, in accordance with Part 5 
of the Accomplishment Instructions of Boeing Special Attention 
Service Bulletin 777-57-0094, Revision 1, dated November 5, 2014.
    (2) Replace the forward attach fitting of the aft flap track of 
the inboard flap with a titanium fitting, in accordance with Part 6 
of the Accomplishment Instructions of Boeing Special Attention 
Service Bulletin 777-57-0094, Revision 1, dated November 5, 2014.

(k) Optional Terminating Actions

    (1) Installation of the nested bushing to the forward attach 
fitting of the aft flap track of the inboard flap, in accordance 
with Part 4 of the Accomplishment Instructions of Boeing Special 
Attention Service Bulletin 777-57-0094, Revision 1, dated November 
5, 2014, terminates the requirements of this AD.
    (2) Replacement of the forward attach fitting of the aft flap 
track of the inboard flap with an aluminum fitting, in accordance 
with Part 5 of the Accomplishment Instructions of Boeing Special 
Attention Service Bulletin 777-57-0094, Revision 1, dated November 
5, 2014, terminates the requirements of this AD.
    (3) Replacement of the forward attach fitting of the aft flap 
track of the inboard flap with a titanium fitting, in accordance 
with Part 6 of the Accomplishment Instructions of Boeing Special 
Attention Service Bulletin 777-57-0094, Revision 1, dated November 
5, 2014, terminates the requirements of this AD.

(l) Exception to the Service Information

    Where Boeing Special Attention Service Bulletin 777-57-0094, 
Revision 1, dated November 5, 2014, specifies a compliance time 
``after the original issue date of this service bulletin,'' this AD 
requires compliance within the specified compliance time after the 
effective date of this AD.

(m) Credit for Previous Actions

    (1) This paragraph provides credit for the actions specified in 
paragraphs (h)(1) and (h)(2) of this AD, if those actions were 
performed before the effective date of this AD using Boeing Special 
Attention Service Bulletin 777-57-0094, dated January 29, 2014, 
which is not incorporated by reference in this AD.
    (2) This paragraph provides credit for the actions specified in 
paragraph (h)(1) of this AD, if those actions were performed before 
the effective date of this AD using Boeing Multi Operator Message 
MOM-MOM-13-0137-01B, dated February 21, 2013, which is not 
incorporated by reference in this AD.

(n) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Seattle Aircraft Certification Office (ACO), 
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 ACO, send it to the 
attention of the person identified in paragraph (o)(1) of this AD. 
Information may be emailed to: [email protected].
    (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.
    (3) An AMOC that provides an acceptable level of safety may be 
used for any repair required by this AD if it is approved by the 
Boeing Commercial Airplanes Organization Designation Authorization 
(ODA) that has been authorized by the Manager, Seattle ACO, to make 
those findings. For a repair method to be approved, the repair must 
meet the certification basis of the airplane, and the approval must 
specifically refer to this AD.
    (4) For service information that contains steps that are labeled 
as Required for Compliance (RC), the provisions of paragraphs 
(n)(4)(i) and (n)(4)(ii) apply.
    (i) The steps labeled as RC, including substeps under an RC step 
and any figures identified in an RC step, must be done to comply 
with the AD. An AMOC is required for any deviations to RC steps, 
including substeps and identified figures.
    (ii) Steps not labeled as RC may be deviated from using accepted 
methods in accordance with the operator's maintenance

[[Page 51495]]

or inspection program without obtaining approval of an AMOC, 
provided the RC steps, including substeps and identified figures, 
can still be done as specified, and the airplane can be put back in 
an airworthy condition.

(o) Related Information

    (1) For more information about this AD, contact Eric Lin, 
Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft 
Certification Office, 1601 Lind Avenue SW., Renton, WA 98057-3356; 
telephone: 425-917-6412; fax: 425-917-6590; email: [email protected].
    (2) For service information identified in this AD, contact 
Boeing Commercial Airplanes, Attention: Data & Services Management, 
P.O. Box 3707, MC 2H-65, Seattle, WA 98124-2207; telephone 206-544-
5000, extension 1; fax 206-766-5680; Internet https://www.myboeingfleet.com. You may view this referenced service 
information at the FAA, Transport Airplane Directorate, 1601 Lind 
Avenue SW., Renton, WA. For information on the availability of this 
material at the FAA, call 425-227-1221.


    Issued in Renton, Washington, on August 17, 2015.
Kevin Hull,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2015-20835 Filed 8-24-15; 8:45 am]
BILLING CODE 4910-13-P