Document ID: FAA-2008-0619-0007
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: The Boeing Company Airplanes
Posted Date: 2012-07-17T04:00Z

[Federal Register Volume 77, Number 137 (Tuesday, July 17, 2012)]
[Proposed Rules]
[Pages 41934-41936]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2012-17393]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2008-0619; Directorate Identifier 2007-NM-356-AD]
RIN 2120-AA64

Airworthiness Directives; The Boeing Company Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Supplemental notice of proposed rulemaking (NPRM); reopening of 
comment period.

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SUMMARY: We are revising an earlier proposed airworthiness directive 
(AD) for all The Boeing Company Model 747-100, 747-100B, 747-100B SUD, 
747-200B, 747-200C, 747-200F, 747-300, 747SR, and 747SP series 
airplanes. That NPRM proposed to require performing repetitive 
operational tests of the engine fuel suction feed of the fuel system, 
and other related testing if necessary. That NPRM was prompted by 
reports of two in-service occurrences on Model 737-400 airplanes of 
total loss of boost pump pressure of the fuel feed system, followed by 
loss of fuel system suction feed capability on one engine, and in-
flight shutdown of the engine. This action revises that NPRM by 
proposing to require repetitive operational tests, and corrective 
actions if necessary. We are proposing this supplemental NPRM to detect 
and correct loss of the engine fuel suction feed capability of the fuel 
system, which in the event of total loss of the fuel boost pumps could 
result in dual engine flameout, inability to restart the engines, and 
consequent forced landing of the airplane. Since these actions impose 
an additional burden over that proposed in the previous NPRM, we are 
reopening the comment period to allow the public the chance to comment 
on these proposed changes.

DATES: We must receive comments on this supplemental NPRM by August 31, 
2012.

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: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE., Washington, DC 20590, 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 review copies of the referenced service 
information at the FAA, Transport Airplane Directorate, 1601 Lind 
Avenue SW., Renton, Washington. For information on the availability of 
this material at the FAA, call 425-227-1221.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov; 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: Sue Lucier, Aerospace Engineer, 
Propulsion Branch, ANM-140S, 1601 Lind Avenue SW., Renton, Washington 
98057-3356; phone: 425-917-6438; fax: 425-917-6590; email: 
suzanne.lucier@faa.gov.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2008-0619; 
Directorate Identifier 2007-NM-356-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 issued an NPRM to amend 14 CFR part 39 to include an AD that 
would apply to all The Boeing Company Model 747-100, 747-100B, 747-100B 
SUD, 747-200B, 747-200C, 747-200F, 747-300, 747SR, and 747SP series 
airplanes. That NPRM published in the Federal Register on June 6, 2008 
(73 FR 32245). That NPRM proposed to require performing repetitive 
operational tests of the engine fuel suction feed of the fuel system, 
and other related testing if necessary.

Actions Since Previous NPRM (73 FR 32245, June 6, 2008) Was Issued

    Since we issued the previous NPRM (73 FR 32245, June 6, 2008), we 
have received comments from operators indicating a high level of 
difficulty performing the actions in the previous NPRM during 
maintenance operations.

Relevant Service Information

    We reviewed Boeing Alert Service Bulletin 747-28A2331, dated April 
2, 2012. This service information describes procedures for repetitive 
operational tests of the engine fuel suction feed of the fuel system, 
and corrective actions if necessary. The corrective actions include 
isolating the cause of any leakage and repairing the leak.

Comments

    We gave the public the opportunity to comment on the previous NPRM 
(73 FR 32245, June 6, 2008). The following presents the comments 
received on the previous NPRM and the FAA's response to each comment.

Requests To Clarify the Reason for the Unsafe Condition/Define Risk 
Assessment

    Boeing and Northwest Airlines (NWA) asked that we clarify the 
reason for the unsafe condition identified in the previous NPRM (73 FR 
32245, June 6, 2008) by including all relevant information.
    Boeing stated that the description of a report of in-service 
occurrences of loss of fuel system suction feed capability results from 
reports of two in-service engine flameout events while operating

[[Page 41935]]

on suction feed with undetected air leak failures on Model 737-400 
airplanes. Boeing added that there are no known reports of any engine 
flameout-related events in the Model 747 fleet. Boeing noted that 
undetected air leaks could exist and the subject maintenance procedure 
is a proactive measure to ensure engine flameout will not occur due to 
air leaks while on suction feed operation.
    NWA asked for an explanation of what caused the failure that 
resulted in issuance of the previous NPRM (73 FR 32245, June 6, 2008), 
and stated that failure analysis could indicate different action than 
the one proposed. NWA added that the events occurred on twin-engine 
airplanes, and requested that we provide the basis for the conclusion 
that Model 747-400 airplanes have the same or greater risk for this 
unsafe condition to occur as twin-engine airplanes.
    We agree that the reason for the unsafe condition should be 
clarified for the reasons provided. We have changed the language in the 
reason for the unsafe condition identified in the Summary section and 
paragraph (e) of this supplemental NPRM to specify that the previous 
NPRM (73 FR 32245, June 6, 2008) was prompted by reports of two in-
service occurrences on Model 737-400 airplanes of total loss of boost 
pump pressure of the fuel feed system, followed by loss of fuel system 
suction feed capability on one engine, and in-flight shutdown of the 
engine.
    The cause of the failure is identified in a failure analysis done 
by Boeing, and incorporates a four-engine airplane in place of a twin-
engine airplane. The differences between the four-engine airplane and 
the twin-engine airplane are reflected in a longer compliance time for 
the four-engine airplane. Although the Model 747 fuel system differs 
with respect to the engine fuel feed design, service data of transport 
category airplanes indicate that multi-engine flameouts have generally 
resulted from a common cause such as fuel mismanagement, crew action 
that inadvertently shuts off the fuel supply to the engines, exposure 
to common environmental conditions, or engine deterioration occurring 
on all engines of the same type. Successful in-flight restart of these 
engines depends on adequate fuel being supplied to the engines solely 
through engine fuel suction feed. Deterioration of the fuel plumbing 
system ``lead-to-line'' (vacuum) reduces engine fuel suction feed 
capability; therefore, directed maintenance is necessary to ensure that 
this system is available to perform its function in order to maintain 
continued safe flight.
    In light of the above, we have determined that Model 747-400, -
400D, and -400F series airplanes are also affected by the identified 
unsafe condition, and are considering additional rulemaking for those 
airplanes.

Request To Issue Certification Maintenance Requirement (CMR) Task 
Instead of Previous NPRM (73 FR 32245, June 6, 2008)

    Japan Airlines (JAL) requested that we withdraw the previous NPRM 
(73 FR 32245, June 6, 2008). JAL asked that instead of issuing an NPRM, 
we issue a CMR task. JAL stated that the requirements in the previous 
NPRM should not be addressed as an AD. JAL did not provide a reason for 
this request.
    We do not agree with the commenter's request. CMRs are developed by 
the Certification Maintenance Coordination Committee (CMCC) during the 
type certification process. The CMCC is made up of manufacturer 
representatives (typically maintenance, design, and safety engineering 
personnel); operator representatives designated by the Industry 
Steering Committee chairperson; aircraft certification office 
specialists, and the maintenance review board (MRB) chairperson. CMRs 
developed during this process become a part of the certification basis 
of the airplane upon issuance of the type certificate. We do not have a 
process for convening the CMCC outside of the type certification 
process; based on this, the CMR is not an option for replacing this AD. 
Regardless, the airworthiness limitations (ALI) were not in the 
maintenance program at the time the previous NPRM (73 FR 32245, June 6, 
2008) was issued; therefore, an AD is required to accomplish the ALI 
task.

Request To Remove or Clarify Certain Language in Paragraph (f) of the 
Previous NPRM (73 FR 32245, June 6, 2008)

    NWA asked that the last sentence in paragraph (f) of the previous 
NPRM (73 FR 32245, June 6, 2008) be removed or clarified. NWA stated 
that the intent of that sentence is unclear, and is reiterated as 
follows: ``Thereafter, except as provided in paragraph (h) of this AD, 
no alternative procedure or repetitive test intervals will be 
allowed.'' NWA added that it is standard practice that once an AD is 
issued, deviation procedures and intervals are not allowed unless 
approved by requesting an alternative method of compliance.
    We agree with the commenter that including the subject sentence is 
redundant; however, that sentence is included in paragraph (g) of the 
supplemental NPRM (paragraph (f) of the previous NPRM (73 FR 32245, 
June 6, 2008)) merely as a reminder for operators of standard 
practices. We have made no change to the supplemental NPRM in this 
regard.

Request To Revise Costs of Compliance Section

    NWA stated that the cost estimate specified in the previous NPRM 
(73 FR 32245, June 6, 2008) is too low, and asked that it be changed. 
NWA stated that the cost of fuel is not included in the cost estimate 
and should be included due to the high cost of fuel.
    We acknowledge the commenter's request. Although fuel is used 
during the operational test, we have not received data on the amount of 
fuel used during the test. In addition, fuel costs vary among 
operators. Therefore, we do not have definitive data that would enable 
us to provide a cost estimate for the fuel costs. In any case, we have 
determined that direct and incidental costs are still outweighed by the 
safety benefits of the AD. We have made no change to the supplemental 
NPRM in this regard.

FAA's Determination

    We are proposing this supplemental NPRM 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. Certain changes described above expand the scope of the 
original NPRM (73 FR 32245, June 6, 2008). As a result, we have 
determined that it is necessary to reopen the comment period to provide 
additional opportunity for the public to comment on this supplemental 
NPRM.

Proposed Requirements of the Supplemental NPRM

    This supplemental NPRM revises the previous NPRM (73 FR 32245, June 
6, 2008) by proposing repetitive operational tests of the engine fuel 
suction feed of the fuel system, and corrective actions if necessary.

Costs of Compliance

    We estimate that this proposed AD would affect 1,080 airplanes of 
U.S. registry. We estimate the following costs to comply with this 
proposed AD:

[[Page 41936]]

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                         Cost per
                 Action                           Labor cost              product       Cost on U.S. operators
----------------------------------------------------------------------------------------------------------------
Operational Test........................  3 work hours x $85 per                $255  $275,400 per engine, per
                                           hour = $255 per engine,                     test.
                                           per test.
----------------------------------------------------------------------------------------------------------------

    We have received no definitive data that would enable us to provide 
a cost estimate for the on-condition actions or the optional 
terminating action specified in this AD.

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

    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]

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

The Boeing Company: Docket No. FAA-2008-0619; Directorate Identifier 
2007-NM-356-AD.

(a) Comments Due Date

    We must receive comments by August 31, 2012.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all The Boeing Company Model 747-100, 747-
100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747SR, 
and 747SP series airplanes, certificated in any category.

(d) Subject

    Joint Aircraft System Component (JASC)/Air Transport Association 
(ATA) of America Code 2800, Aircraft Fuel System.

(e) Unsafe Condition

    This AD was prompted by reports of two in-service occurrences on 
Model 737-400 airplanes of total loss of boost pump pressure of the 
fuel feed system, followed by loss of fuel system suction feed 
capability on one engine, and in-flight shutdown of the engine. We 
are issuing this AD to detect and correct loss of the engine fuel 
suction feed capability of the fuel system, which in the event of 
total loss of the fuel boost pumps could result in dual engine 
flameout, inability to restart the engines, and consequent forced 
landing of the airplane.

(f) Compliance

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

(g) Operational Test and Corrective Actions

    Within 30,000 flight hours after the effective date of this AD: 
Perform an operational test of the engine fuel suction feed of the 
fuel system, and all applicable corrective actions, in accordance 
with the Accomplishment Instructions of Boeing Alert Service 
Bulletin 747-28A2331, dated April 2, 2012. Do all applicable 
corrective actions before further flight. Repeat the operational 
test thereafter at intervals not to exceed 30,000 flight hours. 
Thereafter, except as provided in paragraph (h) of this AD, no 
alternative procedure or repetitive test intervals will be allowed.

(h) 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 the Related Information 
section of this AD. Information may be emailed to: 9-ANM-Seattle-ACO-AMOC-Requests@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 Sue Lucier, 
Aerospace Engineer, Propulsion Branch, ANM-140S, 1601 Lind Avenue 
SW., Renton, Washington 98057-3356; phone: 425-917-6438; fax: 425-
917-6590; email: suzanne.lucier@faa.gov.
    (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 review copies of the referenced 
service information at the FAA, Transport Airplane Directorate, 1601 
Lind Avenue SW., Renton, Washington. For information on the 
availability of this material at the FAA, call 425-227-1221.

    Issued in Renton, Washington, on July 5, 2012.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2012-17393 Filed 7-16-12; 8:45 am]
BILLING CODE 4910-13-P