[Federal Register Volume 72, Number 61 (Friday, March 30, 2007)]
[Proposed Rules]
[Pages 15069-15073]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E7-5928]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2005-21701; Directorate Identifier 2005-NM-086-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 747 and 767 Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

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

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SUMMARY: The FAA is revising an earlier proposed airworthiness 
directive (AD) for certain Boeing Model 747 and 767 airplanes. The 
original NPRM would have required reworking the electrical bonding 
between the airplane structure and the pump housing of the outboard 
boost pumps in the main fuel tank of certain Boeing Model 747 
airplanes, and between the airplane structure and the pump housing of 
the override/jettison pumps in the left and right wing center auxiliary 
fuel tanks of certain Boeing Model 767 airplanes. The original NPRM 
would also have required related investigative actions and corrective 
actions if necessary. The original NPRM resulted from fuel system 
reviews conducted by the manufacturer. This action revises the original 
NPRM by adding an inspection requirement for certain Model 747 
airplanes, and by specifying cold-working the fastener holes for 
certain other Model 747 airplanes. We are proposing this supplemental 
NPRM to prevent insufficient electrical bonding, which could result in 
a potential of ignition sources inside the fuel tanks, and which, in 
combination with flammable fuel vapors, could result in fuel tank 
explosions and consequent loss of the airplane.

DATES: We must receive comments on this supplemental NPRM by April 24, 
2007.

ADDRESSES: Use one of the following addresses to submit comments on 
this supplemental NPRM.
    <bullet> DOT Docket web site: Go to http://dms.dot.gov and follow 
the instructions for sending your comments electronically.
    <bullet> Government-wide rulemaking web site: Go to http://www.regulations.gov and follow the instructions for sending your 
comments electronically.
    <bullet> Mail: Docket Management Facility; U.S. Department of 
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401, 
Washington, DC 20590.
    <bullet> Fax: (202) 493-2251.
    <bullet> Hand Delivery: Room PL-401 on the plaza level of the 
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    Contact Boeing Commercial Airplanes, P.O. Box 3707, Seattle, 
Washington 98124-2207, for service information identified in this 
proposed AD.

FOR FURTHER INFORMATION CONTACT: Philip Sheridan, Aerospace Engineer,

[[Page 15070]]

Systems and Equipment Branch, ANM-130S, FAA, Seattle Aircraft 
Certification Office, 1601 Lind Avenue, SW., Renton, Washington 98057-
3356; telephone (425) 917-6441; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to submit any relevant written data, views, or 
arguments regarding this supplemental NPRM. Send your comments to an 
address listed in the ADDRESSES section. Include the docket number 
``Docket No. FAA-2005-21701; Directorate Identifier 2005-NM-086-AD'' at 
the beginning of your comments. We specifically invite comments on the 
overall regulatory, economic, environmental, and energy aspects of this 
supplemental NPRM. We will consider all comments received by the 
closing date and may amend this supplemental NPRM in light of those 
comments.
    We will post all comments submitted, without change, to http://dms.dot.gov, including any personal information you provide. We will 
also post a report summarizing each substantive verbal contact with FAA 
personnel concerning this supplemental NPRM. Using the search function 
of that Web site, anyone can find and read the comments in any of our 
dockets, including the name of the individual who sent the comment (or 
signed the comment on behalf of an association, business, labor union, 
etc.). You may review the DOT's complete Privacy Act Statement in the 
Federal Register published on April 11, 2000 (65 FR 19477-78), or you 
may visit http://dms.dot.gov.

Examining the Docket

    You may examine the AD docket on the Internet at http://dms.dot.gov, or in person at the Docket Management Facility office 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The Docket Management Facility office (telephone (800) 647-
5227) is located on the plaza level in the Nassif Building at the DOT 
street address stated in ADDRESSES. Comments will be available in the 
AD docket shortly after the Docket Management System receives them.

Discussion

    We proposed to amend 14 CFR part 39 with a notice of proposed 
rulemaking (NPRM) (the ``original NPRM'') for an AD for certain Boeing 
Model 747 and 767 airplanes. The original NPRM was published in the 
Federal Register on June 29, 2005 (70 FR 37293). The original NPRM 
proposed to require reworking the electrical bonding between the 
airplane structure and the pump housing of the outboard boost pumps in 
the main fuel tank of certain Boeing Model 747 airplanes, and between 
the airplane structure and the pump housing of the override/jettison 
pumps in the left and right wing center auxiliary fuel tanks of certain 
Boeing Model 767 airplanes. The original NPRM also proposed to require 
related investigative actions and corrective actions if necessary.

Actions Since Original NPRM Was Issued

    Since we issued the original NPRM, Boeing has issued Boeing Special 
Attention Service Bulletin 747-28-2259, Revision 1, dated October 5, 
2006 (for Boeing Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747-
200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F, 747SR, and 747SP 
series airplanes). The original NPRM referred to Boeing Special 
Attention Service Bulletin 747-28-2259, dated November 4, 2004, as the 
appropriate source of service information for accomplishing certain 
actions.
    Boeing Special Attention Service Bulletin 747-28-2259, Revision 1, 
adds, for Group 1 airplanes, a high frequency eddy current (HFEC) 
inspection for cracks, corrosion, and damage of the fastener holes. 
Revision 1 also indicates reaming to repair those conditions, and gives 
an additional structural repair manual reference for doing the repair; 
but also specifies contacting Boeing if the repair does not eliminate 
cracks, corrosion, or damage when reamed to 0.2942- to 0.2962-inch in 
diameter. Revision 1 also adds a step that specifies cold-working the 
fastener holes for Group 2 airplanes; adds and revises certain part 
numbers for certain rivets; removes the step that specifies emptying 
fuel from the outboard main fuel tanks; clarifies an illustration of 
the new bonding rivets; and clarifies the measurements of the bonding 
resistance.

Comments

    We have considered the following comments on the original NPRM.

Support for the Original NPRM

    US Airways supports the original NPRM.

Request To Use New Revision of Service Bulletin

    Japan Airlines (JAL) requests that we refer to Boeing Special 
Attention Service Bulletin 747-28-2259, Revision 1, rather than the 
original issue of the service bulletin (Boeing Special Attention 
Service Bulletin 747-28-2259, dated November 4, 2004, was referred to 
as the appropriate source of service information for accomplishing the 
required actions). JAL also would like to confirm that it is acceptable 
to use the original issue of the service bulletin for compliance with 
the original NPRM, if the actions are done before the effective date of 
the AD.
    We agree with JAL's requests. We have revised this supplemental 
NPRM to refer to Revision 1 of the service bulletin. We have also added 
a new paragraph (g) to this supplemental NPRM to give operators credit 
for accomplishing the applicable actions before the effective date of 
the AD in accordance with the original issue of the service bulletin. 
We have also re-identified subsequent paragraphs accordingly.

Requests To Extend Compliance Time

    Boeing, British Airways, Royal Dutch Airlines (KLM), and the Air 
Transport Association (ATA) on behalf of one of its members, Delta 
Airlines, all request that we extend the 60-month compliance time for 
reworking the electrical bonding, as described below.
    Boeing, British Airways, and KLM request a 72-month compliance time 
because it is the threshold that the manufacturer recommends. British 
Airways and KLM discussed this issue with Boeing and advise that the 
60-month compliance time pre-dates Boeing's latest risk management 
guidelines for Special Federal Aviation Regulation (SFAR) 88 issues and 
is, therefore, out of step with current Boeing analyses. Boeing 
confirms that it initially recommended a 60-month compliance time 
before the completion of a formal compliance recommendation process. As 
such, the 60-month compliance time does not reflect current analyses. 
Boeing subsequently submitted a letter to the FAA that proposes a 72-
month compliance time for all SFAR 88 design changes, with the 
exception of those associated with fuel pump inlet protection.
    British Airways supports its request to extend the compliance time 
from 60 months to 72 months by asking us to consider an interim action. 
The proposed interim action would be any fuel pump housing replacement 
that is mounted and electrically bonded to the AD-affected under-wing 
housing. British Airways proposes an alternate ground path through the 
fasteners of the pump housing. If this bond can be verified, British 
Airways states that it justifies a 12-month extension to the compliance 
time.
    Delta Airlines requests an 84-month compliance time because it 
would allow operators to accomplish the proposed actions during 
scheduled substantial

[[Page 15071]]

aircraft maintenance visits due to complete de-fueling requirements. 
Delta states that an 84-month compliance time would also prevent undue 
financial and scheduling burdens.
    We disagree with the requests to change the compliance time from 60 
months to 72 or 84 months. In establishing the proposed compliance 
time, we considered not only the manufacturer's recommendation, but 
also the labor required to accomplish the actions, and the risks to the 
airplane if these actions are not done in a timely manner. We also 
considered that the alternate ground path proposed by British Airways 
does not have sufficient current-carrying capability (as stated in 
Boeing Special Attention Service Bulletin 747-28-2259); and we have 
taken into account the fact that there is a primary bond path. We 
determined that a 60-month compliance time is adequate for operators to 
schedule the task during heavy maintenance visits, and that it will 
provide an adequate level of safety. In further discussions, Boeing 
agrees with the 60-month compliance time for this supplemental NPRM.
    However, operators may request approval of an alterative method of 
compliance (AMOC) in accordance with the procedures specified in 
paragraph (h) of this supplemental NPRM. The AMOC request must contain 
appropriate rationale to substantiate that the AMOC will maintain an 
acceptable level of safety. Operators outside the United States must 
work with the applicable regulatory authority regarding this process.
    We have not changed the supplemental NPRM in this regard.

Request To Use Operator's Equivalent Procedures for Certain Repairs

    ATA, on behalf of one of its members, Northwest Airlines, is 
concerned that the requirement to obtain FAA or authorized Boeing 
representative approval for repairs of crack or corrosion findings 
could have additional cost and schedule implications. Northwest 
Airlines states that obtaining this approval is outside the intent of 
the modification, and should be addressed with existing Northwest 
Airlines procedures, which may or may not require FAA approval. 
Northwest Airlines states that it would perform the specified bonding 
resistance checks to verify that there are still proper ground paths 
and current-carrying capabilities.
    We disagree with changing the supplemental NPRM to remove the 
requirement to contact the FAA or authorized Boeing representative. 
Structural repair manual (SRM) repair procedures are spelled out in 
both Boeing Special Attention Service Bulletin 747-28-2259, dated 
November 4, 2004; and Boeing Special Attention Service Bulletin 747-28-
2259, Revision 1, dated October 5, 2006. Revision 1 also adds an 
additional SRM reference, and specifies contacting a Boeing 
representative for the repairs only if the SRM repair is not clean of 
cracks, corrosion, or damage when reamed to 0.2942- to 0.2962-inch in 
diameter. Approval of any deviation from the requirements of this 
supplemental NPRM, such as operator's equivalent or existing 
procedures, may be requested in accordance with the AMOC procedures 
specified in paragraph (h) of this supplemental NPRM. The AMOC request 
must contain appropriate rationale to substantiate that the AMOC will 
maintain an acceptable level of safety. We have not changed the 
supplemental NPRM in this regard.

Request To Clarify HFEC Inspection for Group 1 Airplanes

    British Airways points out that Boeing Special Attention Service 
Bulletin 747-28-2259, dated November 4, 2004, specifies an HFEC 
inspection for defects after rework only for Group 2 airplanes, but for 
Group 1 airplanes the service bulletin does not state what inspections, 
if any, are necessary after reworking the holes. British Airways 
normally would expect, for all airplanes, to oversize the rivet holes, 
follow the SRM specifications, and progressively remove any damage. If 
it is the FAA's intent to subject Group 1 airplanes and Group 2 
airplanes to the HFEC inspection, British Airways requests that we 
include a statement indicating that it affects both groups. However, 
British Airways believes that this statement would be best published in 
the service bulletin.
    We agree that the inspection applies to both Group 1 and Group 2 
airplanes. As stated previously, Boeing has issued Revision 1 of Boeing 
Special Attention Service Bulletin 747-28-2259, which makes the change 
that British Airways requests. We have changed the supplemental NPRM to 
refer to Revision 1 of the service bulletin.

Clarification of AMOC Paragraph

    We have revised this action to clarify the appropriate procedure 
for notifying the principal inspector before using any approved AMOC on 
any airplane to which the AMOC applies.

Explanation of Change to Costs of Compliance

    After the original NPRM was issued, we reviewed the figures we have 
used over the past several years to calculate AD costs to operators. To 
account for various inflationary costs in the airline industry, we find 
it necessary to increase the labor rate used in these calculations from 
$65 per work hour to $80 per work hour. The cost information, below, 
reflects this increase in the specified hourly labor rate.

FAA's Determination and Proposed Requirements of the Supplemental NPRM

    The changes discussed above expand the scope of the original NPRM; 
therefore, we have determined that it is necessary to reopen the 
comment period to provide additional opportunity for public comment on 
this supplemental NPRM.

Difference Between the Supplemental NPRM and Boeing Special Attention 
Service Bulletin 747-28-2259, Revision 1

    Although Boeing Special Attention Service Bulletin 747-28-2259, 
Revision 1, specifies contacting the manufacturer if any crack, 
corrosion, or damage that exceeds certain limits is found during the 
open-hole HFEC inspection, this supplemental NPRM would require 
operators to repair those conditions in one of the following ways:
    <bullet> Using a method that we approve; or
    <bullet> Using data that meet the certification basis of the 
airplane, and that have been approved by an Authorized Representative 
for the Boeing Commercial Airplanes Delegation Option Authorization 
Organization whom we have authorized to make those findings.

Costs of Compliance

    There are about 3,401 airplanes of the affected design in the 
worldwide fleet. The following table provides the estimated costs for 
U.S. operators to comply with this supplemental NPRM.

[[Page 15072]]



                                                 Estimated Costs
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                                                                                         Number of
                                                                Average      Cost per      U.S.-
                     Action                       Work hours   labor rate    airplane    registered   Fleet cost
                                                                per hour                 airplanes
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Rework electrical bonding for Boeing Model 747            10          $80         $800        1,115     $892,000
 airplanes.....................................
Rework electrical bonding for Boeing Model 767             9           80          720          921      663,120
 airplanes.....................................
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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 have 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 that the 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); 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.
    We prepared a regulatory evaluation of the estimated costs to 
comply with this supplemental NPRM and placed it in the AD docket. See 
the ADDRESSES section for a location to examine the regulatory 
evaluation.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, 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 Federal Aviation Administration (FAA) amends Sec.  39.13 by 
adding the following new airworthiness directive (AD):

Boeing: Docket No. FAA-2005-21701; Directorate Identifier 2005-NM-
086-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by April 24, 
2007.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to the Boeing airplane models identified in 
Table 1 of this AD, certificated in any category.

                 Table 1.--Airplanes Affected by This AD
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                                               As identified in Boeing
                  Model--                     Special Attention Service
                                                     Bulletin--
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747-100, 747-100B, 747-100B SUD, 747-200B,  747-28-2259, Revision 1,
 747-200C, 747-200F, 747-300, 747-400, 747-  dated October 5, 2006.
 400D, 747-400F, 747SR, and 747SP series
 airplanes.
767-200, -300, and -300F series airplanes.  767-57-0092, dated November
                                             4, 2004.
767-400ER series airplanes................  767-57-0093, dated November
                                             4, 2004.
------------------------------------------------------------------------

Unsafe Condition

    (d) This AD was prompted by the results of fuel system reviews 
conducted by the manufacturer. We are issuing this AD to prevent 
insufficient electrical bonding, which could result in a potential 
of ignition sources inside the fuel tanks, and which, in combination 
with flammable fuel vapors, could result in fuel tank explosions and 
consequent loss of the airplane.

Compliance

    (e) You are responsible for having the actions required by this 
AD performed within the compliance times specified, unless the 
actions have already been done.

Rework Electrical Bonding

    (f) Within 60 months after the effective date of this AD: Do the 
actions specified in paragraph (f)(1) or (f)(2) of this AD, as 
applicable, by accomplishing all the actions specified in the 
Accomplishment Instructions of the applicable service bulletin in 
Table 1 of this AD. Do any related investigative and corrective 
actions before further flight.
    (1) For Boeing Model 747-100, 747-100B, 747-100B SUD, 747-200B, 
747-200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F, 747SR, and 
747SP series airplanes: Rework the electrical bonding between the 
airplane structure and the pump housing of the outboard boost pumps 
in the main fuel tank, and do related investigative and applicable 
corrective actions. If any crack, corrosion, or damage is found 
during the open-hole high-frequency eddy current (HFEC) inspection 
specified in Boeing Special Attention Service Bulletin 747-28-2259, 
Revision 1, dated October 5, 2006, and the special attention service 
bulletin specifies contacting Boeing for repair instructions: Before 
further flight, repair in accordance with a method approved by the 
Manager, Seattle Aircraft Certification Office (ACO), FAA; or in 
accordance with data meeting the certification basis of the airplane 
approved by an Authorized Representative for the Boeing Commercial 
Airplanes Delegation Option Authorization Organization who has been 
authorized by the Manager, Seattle

[[Page 15073]]

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 reference this AD.
    (2) For Boeing Model 767-200, -300, -300F, and -400ER series 
airplanes: Rework the electrical bonding between the airplane 
structure and the pump housing of the override/jettison pumps in the 
left and right wing center auxiliary fuel tanks, and do the related 
investigative and applicable corrective actions.

Credit for Actions Accomplished Previously

    (g) Actions done before the effective date of this AD in 
accordance with Boeing Special Attention Service Bulletin 747-28-
2259, dated November 4, 2004, are acceptable for compliance with the 
corresponding requirements of paragraph (f)(1) of this AD.

Alternative Methods of Compliance (AMOCs)

    (h)(1) The Manager, Seattle ACO, FAA, has the authority to 
approve AMOCs for this AD, if requested in accordance with the 
procedures found in 14 CFR 39.19.
    (2) Before using any AMOC approved in accordance with Sec.  
39.19 on any airplane to which the AMOC applies, notify the 
appropriate principal inspector in the FAA Flight Standards 
Certificate Holding District Office.

    Issued in Renton, Washington, on March 23, 2007.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
 [FR Doc. E7-5928 Filed 3-29-07; 8:45 am]
BILLING CODE 4910-13-P