[Federal Register Volume 70, Number 60 (Wednesday, March 30, 2005)]
[Proposed Rules]
[Pages 16177-16180]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-6251]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2005-20725; Directorate Identifier 2003-NM-250-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 707-300B, -300C, and -400 
Series Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for all Boeing Model 707-300B, -300C, and -400 series airplanes. This 
proposed AD would require repetitive inspections to detect cracked or 
broken hinge fitting assemblies of the inboard leading edge slats, and 
corrective action if necessary. This proposed AD would provide as an 
option a preventive modification, which would defer the repetitive 
inspections. This proposed AD also would provide an option of replacing 
all hinge fitting assemblies with new, improved parts, which would 
terminate the repetitive inspection requirements. This proposed AD is 
prompted by results of a review to identify and implement procedures to 
ensure the continued structural airworthiness of aging transport 
category airplanes. We are proposing this AD to detect and correct 
fatigue cracking of the hinge fitting assembly of the inboard leading 
edge slats, which could result in reduced structural integrity of the 
slat system. This condition could result in loss of the inboard leading 
edge slat and could cause the flightcrew to lose control of the 
airplane.

DATES: We must receive comments on this proposed AD by May 16, 2005.

ADDRESSES: Use one of the following addresses to submit comments on 
this proposed AD.
     DOT Docket Web site: Go to http://dms.dot.gov and follow 
the instructions for sending your comments electronically.
     Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your 
comments electronically.
     Mail: Docket Management Facility, U.S. Department of 
Transportation, 400 Seventh Street SW., Nassif Building, room PL-401, 
Washington, DC 20590.
     By fax: (202) 493-2251.
     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.
    You can get the service information identified in this proposed AD 
from Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 
98124-2207.
    You may examine the contents of this AD docket on the Internet at 
http://dms.dot.gov, or at the Docket Management Facility, U.S. 
Department of Transportation, 400 Seventh Street SW., room PL-401, on 
the plaza level of the Nassif Building, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Candice Gerretsen, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA Seattle Aircraft Certification Office, 
1601 Lind Avenue SW., Renton, Washington 98055-4056; telephone (425) 
917-6428; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION:

Docket Management System (DMS)

    The FAA has implemented new procedures for maintaining AD dockets 
electronically. As of May 17, 2004, new AD actions are posted on DMS 
and assigned a docket number. We track each action and assign a 
corresponding directorate identifier. The DMS AD docket number is in 
the form ``Docket No. FAA-2004-99999.'' The Transport Airplane 
Directorate identifier is in the form ``Directorate Identifier 2004-NM-

[[Page 16178]]

999-AD.'' Each DMS AD docket also lists the directorate identifier 
(``Old Docket Number'') as a cross-reference for searching purposes.

Comments Invited

    We invite you to submit any written relevant data, views, or 
arguments regarding this proposed AD. Send your comments to an address 
listed under ADDRESSES. Include ``Docket No. FAA-2005-20725; 
Directorate Identifier 2003-NM-250-AD'' in the subject line of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of the proposed AD. We will 
consider all comments submitted by the closing date and may amend the 
proposed AD in light of those comments.
    We will post all comments we receive, 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 proposed AD. Using the search function of 
that website, 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 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.
    We are reviewing the writing style we currently use in regulatory 
documents. We are interested in your comments on whether the style of 
this document is clear, and your suggestions to improve the clarity of 
our communications that affect you. You can get more information about 
plain language at http://www.faa.gov/language and http://www.plainlanguage.gov.

Examining the Docket

    You may examine the AD docket 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 of the Nassif 
Building at the DOT street address stated in the ADDRESSES section. 
Comments will be available in the AD docket shortly after the DMS 
receives them.

Discussion

    The Air Transport Association (ATA) of America and the Aerospace 
Industries Association (AIA) of America agreed to undertake the task of 
identifying and implementing procedures to ensure the continued 
structural airworthiness of aging transport category airplanes. An 
Airworthiness Assurance Working Group (AAWG) was established in August 
1988, with members representing aircraft manufacturers, operators, 
regulatory authorities, and other aviation industry representatives 
worldwide. The objective of the AAWG was to sponsor ``Task Groups'' to:
    1. Select service bulletins, applicable to each airplane model in 
the transport fleet, to be recommended for mandatory modification of 
aging airplanes;
    2. Develop corrosion-directed inspections and prevention programs;
    3. Review the adequacy of each operator's structural maintenance 
program;
    4. Review and update the Supplemental Inspection Documents (SID); 
and
    5. Assess repair quality.
    Based on the results of this review, the task group for Boeing 
Model 707 series airplanes recommended replacing all hinge fitting 
assemblies on Boeing Model 707-300B, -300C, and -400 series airplanes 
to prevent fatigue cracking of the hinge fitting assembly of the 
inboard leading edge slats, which could result in reduced structural 
integrity of the slat system. This condition could result in loss of 
the inboard leading edge slat, which could cause the flightcrew to lose 
control of the airplane.
    We partially agree with the task group's recommendation. We agree 
that corrective action is necessary to address the identified unsafe 
condition. However, we do not agree with the recommendation to mandate 
the replacement of all hinge fitting assemblies for the following 
reasons:
    1. Accessing the hinge fitting assemblies for inspection is easily 
accomplished; and
    2. Cracked or broken assemblies are easily detectable by means of a 
visual inspection.

Relevant Service Information

    We have reviewed Boeing Service Bulletin 2982, Revision 2, dated 
October 7, 1977. This service bulletin describes procedures for doing 
repetitive dye penetrant inspections to detect cracked or broken hinge 
fitting assemblies of the inboard leading edge slats, and corrective 
action if necessary. The corrective action replaces any cracked or 
broken hinge fitting assembly with the following:
     A like serviceable part;
     A like serviceable part on which the preventative 
modification (described below) has been done. This replacement defers 
the repetitive inspections for 1.5 times the total flight hours at the 
time of modification for that hinge fitting assembly; or
     A new, improved part. This replacement ends the repetitive 
inspections for that hinge fitting assembly.
    As an option to the repetitive dye penetrant inspections, this 
service bulletin also describes procedures for a preventive 
modification, which consists of a magnetic particle inspection and 
rework of the hinge fitting assembly. This preventive modification 
provides a new threshold for doing the repetitive dye penetrant 
inspections of the hinge fitting assemblies. This service bulletin also 
describes procedures for replacing all hinge fitting assemblies with 
new, improved parts, which ends the repetitive inspections. We have 
determined that accomplishment of the actions specified in the service 
bulletin will adequately address the unsafe condition.

FAA's Determination and Requirements of the Proposed AD

    We have evaluated all pertinent information and identified an 
unsafe condition that is likely to exist or develop on other airplanes 
of this same type design. Therefore, we are proposing this AD, which 
would require repetitive dye penetrant inspections of the hinge fitting 
assemblies of the inboard leading edge slats to detect cracks or broken 
parts of the hinge fitting assemblies of the inboard leading edge, and 
corrective action if necessary. This proposed AD would provide as an 
option a preventive modification, which would defer the repetitive dye 
penetrant inspections. This proposed AD also would provide an option of 
replacing all hinge fitting assemblies with new, improved parts, which 
would terminate the repetitive inspection requirements. The proposed AD 
would require you to use the service information described previously 
to perform these actions, except as discussed under ``Differences 
Between the Proposed AD and the Service Bulletin.''

Differences Between the Proposed AD and the Service Bulletin

    The service bulletin gives a new inspection threshold following a 
preventive modification that is ``equal to 1.5 times the accumulated 
flight hours at the time of the modification.'' This preventive 
modification is included in paragraph (i) of this proposed AD. Instead 
of allowing a threshold that

[[Page 16179]]

multiplies the current number of flight hours, paragraph (i) proposes 
to limit the inspection threshold to 15,000 flight hours following the 
preventive modification. We have made this change to the inspection 
threshold because, when the service bulletin was originally released in 
1970, the affected airplanes had relatively few total flight hours. All 
affected airplanes now have significantly more total flight hours--in 
one case, more than 90,000. We find that allowing a threshold of 1.5 
times the flight hours of any airplane in the current fleet would not 
provide an adequate level of safety.
    This proposed AD also differs from the service bulletin in that it 
applies to Boeing Model 707-400 series airplanes as well as the Boeing 
Model 707-300B and -300C series airplanes specified in the service 
bulletin. As stated earlier in this proposed AD, the inboard leading 
edge slats on the Model 707-400 series airplanes have the same 
configuration as that on the affected Model 707-300B and -300C series 
airplanes. Therefore, those Model 707-400 series airplanes may be 
subject to the same unsafe condition as the Model -300B, and -300C 
series airplanes. In addition, the procedures in the service bulletin 
also address the unsafe condition on the Model 707-400 series 
airplanes.
    The service bulletin does not provide procedures for repairing any 
crack found during the magnetic particle inspection (part of the 
preventative modification). This proposed AD would require you to do 
the corrective action specified in paragraph (h) of the proposed AD.
    We have coordinated the differences discussed above with the 
airplane manufacturer.

Clarification Between the Proposed AD and the Service Bulletin

    The service bulletin allows operators to use a ``like serviceable 
part.'' For this proposed AD, we have defined ``like serviceable part'' 
as a serviceable part listed in the ``Existing'' part number column of 
Table II of the service bulletin that has been inspected and found to 
be crack free in accordance with paragraph (g) of this AD before 
installation. A ``new part'' is a part listed in the ``Replacement'' or 
``Optional'' part number column of Table II of the service bulletin.

Costs of Compliance

    This proposed AD would affect about 189 Boeing Model 707-300B, -
300C, and -400 series airplanes worldwide. The following table provides 
the estimated costs for U.S. operators to comply with this proposed AD.

                                                 Estimated Costs
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                                                                                                      Number of
                                                   Average                                              U.S.-
             Action                Work hours    labor rate         Parts        Cost per airplane   registered
                                                  per hour                                            airplanes
----------------------------------------------------------------------------------------------------------------
Dye Penetrant Inspection........             3           $65  None............  $195 (per                     16
                                                                                 inspection cycle).
Preventive Modification                     10            65  None............  650 (per                      16
 (Optional).                                                                     inspection).
Terminating Action (Optional)...            10            65  $8,220..........  8,870.............            16
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Authority for This Rulemaking

    The FAA's authority to issue rules regarding aviation safety is 
found in Title 49 of the United States Code. 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.
    This rulemaking is promulgated 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 AD.

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

Boeing: Docket No. FAA-2005-20725; Directorate Identifier 2003-NM-
250-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this AD action by May 16, 2005.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to all Boeing Model 707-300B, -300C, and -
400 series airplanes, certificated in any category.

Unsafe Condition

    (d) This AD was prompted by results of a review to identify and 
implement procedures to ensure the continued structural 
airworthiness of aging transport category airplanes. We are 
proposing this AD to detect and correct fatigue cracking of the 
hinge fitting assembly of the inboard leading edge slats, which 
could result in reduced

[[Page 16180]]

structural integrity of the slat system. This condition could result 
in loss of the inboard leading edge slat and could cause the 
flightcrew to lose control 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.

Service Bulletin Reference

    (f) In this AD, the term ``service bulletin'' means the 
Accomplishment Instructions of Boeing Service Bulletin 2982, 
Revision 2, dated October 7, 1977.

Repetitive Inspections

    (g) Before the accumulation of 10,000 total flight hours, or 
within 1,500 flight hours after the effective date of this AD, 
whichever occurs later, do a dye penetrant inspection to detect 
cracked or broken hinge fitting assemblies of the inboard leading 
edge slats in accordance with Part I, ``Inspection Data,'' of the 
service bulletin. Repeat the inspection at intervals not to exceed 
1,500 flight hours, except as provided by paragraph (i) or (k) of 
this AD.

Corrective Action

    (h) If any crack or broken assembly is found during any 
inspection required by paragraph (g) of this AD, before further 
flight, do the action specified in paragraph (h)(1), (h)(2), or 
(h)(3) of this AD.
    (1) Replace the hinge fitting assembly with like serviceable 
part in accordance with Part I of the service bulletin.
    (2) Replace the hinge fitting assembly with like serviceable 
part on which the preventative modification specified in paragraph 
(i) of this AD has been done, in accordance with Part II of the 
service bulletin. This replacement defers the repetitive inspection 
requirements of paragraph (g) of this AD for 15,000 flight hours for 
that hinge fitting assembly.
    (3) Replace the hinge fitting assembly with a new, improved part 
in accordance with Part III of the service bulletin. This 
replacement terminates the repetitive inspection requirements of 
paragraph (g) of this AD for that hinge fitting assembly.

    Note 1: For this AD, a ``like serviceable part'' is a 
serviceable part listed in the ``Existing'' part number column of 
Table II of the service bulletin that has been inspected and found 
to be crack free in accordance with paragraph (g) of this AD before 
installation. A ``new part'' is a part listed in the ``Replacement'' 
or ``Optional'' part number column of Table II of the service 
bulletin.

Optional Preventative Modification (Defers Repetitive Inspections)

    (i) Do a preventative modification by accomplishing all the 
procedures in Part II of the service bulletin, except as required by 
paragraph (j) of this AD. Within 15,000 flight hours after the 
preventive modification, do the repetitive inspections in paragraph 
(g) of this AD at intervals not to exceed 1,500 flight hours.
    (j) If any crack is found during the preventative modification 
specified in paragraph (i) of this AD, before further flight, do the 
action specified in paragraph (h) of this AD.

Optional Terminating Action

    (k) Replacement of a hinge fitting assembly with a new, improved 
part terminates the repetitive inspection requirements of paragraph 
(g) of this AD for that assembly. Replacement of all hinge fitting 
assemblies with new, improved parts terminates the repetitive 
inspection requirements of this AD. The replacement must be done in 
accordance with Part III of the service bulletin.

Actions Accomplished Using a Previous Issue of the Service Bulletin

    (l) Actions accomplished before the effective date of this AD 
using Boeing Service Bulletin 2982, Revision 1, dated June 29, 1970, 
are considered acceptable for compliance with the corresponding 
action in this AD.

Alternative Methods of Compliance (AMOCs)

    (m)(1) The Manager, Seattle Aircraft Certification Office (ACO) 
has the authority to approve AMOCs for this AD, if requested using 
the procedures found in 14 CFR 39.19.
    (2) An AMOC that provides an acceptable level of safety may be 
used for a preventive modification of hinge fitting assemblies of 
the inboard leading edge slat if it is approved by an Authorized 
Representative for the Boeing Delegation Option Authorization 
Organization who 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.

    Issued in Renton, Washington, on March 17, 2005.
Jeffery E. Duven,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 05-6251 Filed 3-29-05; 8:45 am]
BILLING CODE 4910-13-P