[Federal Register Volume 69, Number 30 (Friday, February 13, 2004)]
[Proposed Rules]
[Pages 7174-7176]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-3132]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2003-NM-44-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 707 and 720 Series 
Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the adoption of a new airworthiness 
directive (AD) that is applicable to all Boeing Model 707 and 720 
series airplanes. This proposal would require an inspection of the main 
landing gear (MLG) lock support fitting and the wing fillet flap 
support link for damage, and corrective action, if necessary; and 
replacement of the bolts and bushings at the joint between the MLG lock 
support fitting and the wing fillet flap support link. This action is 
necessary to prevent stress corrosion cracking of the bolts and wearing 
of the joint between the lock support fitting and the support link, 
which could lead to failure of the joint and could cause the collapse 
of the MLG. This action is intended to address the identified unsafe 
condition.

DATES: Comments must be received by March 29, 2004.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2003-NM-44-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056. Comments may be inspected at this 
location between 9 a.m. and 3 p.m., Monday through Friday, except 
Federal holidays. Comments may be submitted via fax to (425) 227-1232. 
Comments may also be sent via the Internet using the following address: 
[email protected]. Comments sent via fax or the Internet must 
contain ``Docket No. 2003-NM-44-AD'' in the subject line and need not 
be submitted in triplicate. Comments sent via the Internet as attached 
electronic files must be formatted in Microsoft Word 97 or 2000 or 
ASCII text.
    The service information referenced in the proposed rule may be 
obtained from Boeing Commercial Airplanes, P.O. Box 3707, Seattle, 
Washington 98124-2207. This information may be examined at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington.

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:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed rule by submitting such written data, views, or arguments as 
they may desire. Communications shall identify the Rules Docket number 
and be submitted in triplicate to the address specified above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule. The proposals contained in this action may be changed in 
light of the comments received.
    Submit comments using the following format:
     Organize comments issue-by-issue. For example, 
discuss a request to change the compliance time and a request to change 
the service bulletin reference as two separate issues.
     For each issue, state what specific change to 
the proposed AD is being requested.
     Include justification (e.g., reasons or data) 
for each request.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the proposed rule. All 
comments submitted will be available, both before and after the closing 
date for comments, in the Rules Docket for examination by interested 
persons. A report summarizing each FAA-public contact concerned with 
the substance of this proposal will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this action must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 2003-NM-44-AD.'' The postcard will be date stamped and 
returned to the commenter.

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules 
Docket No. 2003-NM-44-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The FAA has received a report that one operator found a corroded 
and worn bolt and bushings at the joint between the main landing gear 
(MLG) lock support fitting and the wing fillet flap support link on a 
Boeing Model 707-300 series airplane. Stress corrosion cracking of the 
bolts and wearing of the joint between the lock support fitting and the 
support link could lead to failure of the joint. This condition, if not 
corrected, could cause the collapse of the MLG.

Explanation of Relevant Service Information

    The FAA has reviewed and approved Boeing 707 Alert Service Bulletin 
A3511, dated February 23, 2003, which describes procedures for 
performing a high frequency eddy current inspection of the MLG lock 
support fitting and the wing fillet flap support link for damage, and 
corrective action, if necessary; and replacing bolts and bushings at 
the joint between the MLG lock support fitting and the wing fillet flap 
support link with new CRES bolts and Cadmium-plated Al-Ni-Br bushings. 
The corrective action includes reworking or replacing the MLG lock 
support fitting and/or the wing fillet flap support link; and 
contacting Boeing for repair or replacement if damage is beyond rework 
limits. Accomplishment of the actions specified in the service bulletin 
is intended to adequately address the identified unsafe condition.

Explanation of Requirements of Proposed Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other products of this same type design, the 
proposed AD would require accomplishment of the actions specified in 
the service bulletin described previously, except as discussed below.

Differences Between Proposed Rule and Service Bulletin

    Operators should note that, although Boeing 707 Alert Service 
Bulletin A3511, dated January 23, 2003, specifies that the manufacturer 
may be contacted for rework limits, this proposal would require the 
repair or replacement of the MLG lock support fitting or the wing 
fillet flap support link to be accomplished per a method approved by 
the FAA, or per data meeting the type certification basis of the 
airplane approved by a Boeing Company Designated Engineering 
Representative who has been authorized by the FAA to make such 
findings.
    Although Boeing 707 Alert Service Bulletin A3511, dated January 23, 
2003, specifies to rework the forward and aft lug bore and faces of the 
MLG lock support fitting as given in Boeing Service Bulletin 707-2837, 
the service bulletin does not specify a specific revision level. This 
proposal would require rework to be accomplished in accordance with 
Revision 5 of Boeing Service Bulletin 707-2837, dated March 31, 1978.

Clarification of Wording in Service Bulletin

    Due to the existence of two different configurations, the service 
bulletin uses the terms ``trailing edge support link'' and ``wing 
fillet flap support link'' to describe the attachment point to the

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MLG lock support fitting. For the purposes of this AD the term 
``support link'' is used to simplify the AD.

Cost Impact

    There are approximately 230 airplanes of the affected design in the 
worldwide fleet. The FAA estimates that 42 airplanes of U.S. registry 
would be affected by this proposed AD, that it would take approximately 
14 work hours per airplane to accomplish the proposed replacement and 
inspection, and that the average labor rate is $65 per work hour. Based 
on these figures, the cost impact of the proposed AD on U.S. operators 
is estimated to be $38,220, or $910 per airplane.
    The cost impact figure discussed above is based on assumptions that 
no operator has yet accomplished any of the proposed requirements of 
this AD action, and that no operator would accomplish those actions in 
the future if this proposed AD were not adopted. The cost impact 
figures discussed in AD rulemaking actions represent only the time 
necessary to perform the specific actions actually required by the AD. 
These figures typically do not include incidental costs, such as the 
time required to gain access and close up, planning time, or time 
necessitated by other administrative actions.

Regulatory Impact

    The regulations proposed herein 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. Therefore, it 
is determined that this proposal would not have federalism implications 
under Executive Order 13132.
    For the reasons discussed above, I certify that 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); 
and (3) if promulgated, will not have a significant economic impact, 
positive or negative, on a substantial number of small entities under 
the criteria of the Regulatory Flexibility Act. A copy of the draft 
regulatory evaluation prepared for this action is contained in the 
Rules Docket. A copy of it may be obtained by contacting the Rules 
Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

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

PART 39--AIRWORTHINESS DIRECTIVES

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

    Authority: 49 U.S.C. 106(g), 40113, 44701.


Sec. 39.13  [Amended]

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

Boeing: Docket 2003-NM-44-AD.

    Applicability: All Model 707 and 720 series airplanes, 
certificated in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent stress corrosion cracking of the bolts and wearing of 
the joint between the lock support fitting and the support link, 
which could lead to failure of the joint and could cause the 
collapse of the main landing gear (MLG), accomplish the following:

Service Bulletin References

    (a) The term ``service bulletin,'' as used in this AD, means the 
Accomplishment Instructions of Boeing 707 Alert Service Bulletin 
A3511, dated January 23, 2003.

Initial Inspection

    (b) Within 12 months or 1,000 flight cycles after the effective 
date of this AD, whichever comes first, perform a high frequency 
eddy current (HFEC) inspection of the MLG lock support fitting and 
the support link for cracks and corrosion in accordance with the 
service bulletin.

Corrective Actions

    (c) If any crack or corrosion is found, during the HFEC 
inspection required by paragraph (b) of this AD, before further 
flight, rework the lock support fitting or support link, in 
accordance with the service bulletin, except as specified in 
paragraphs (c)(1) and (c)(2) of this AD.
    (1) If the service bulletin specifies to contact Boeing for 
rework limits: Before further flight, repair or replace the lock 
support fitting or support link per a method approved by the 
Manager, Seattle Aircraft Certification Office (ACO), FAA; or per 
data meeting the type certification basis of the airplane approved 
by a Boeing Company Designated Engineering Representative who has 
been authorized by the Manager, Seattle ACO, to make such findings. 
For a repair/replacement method to be approved, the approval must 
specifically reference this AD.
    (2) Where the service bulletin specifies to rework the forward 
and aft lug bore and faces common to the lock support fitting of the 
MLG as given in Boeing Service Bulletin 707-2837, this AD requires 
rework to be accomplished only in accordance with Revision 5 of 
Boeing Service Bulletin 707-2837, dated March 31, 1978.

Replacement of Bolts and Bushings

    (d) Within 12 months or 1,000 flight cycles after the effective 
date of this AD, whichever comes first, replace the bolts and 
bushings at the joint between the lock support fitting for the MLG 
and the wing fillet flap with new CRES bolts and Cadmium-plated Al-
Ni-Br bushings in accordance with the service bulletin.

Parts Installation

    (e) As of the effective date of this AD, no person shall install 
a bolt, part number BACB30LU10D* or NAS590-*, at the joint between 
the MLG lock support fitting and the support link, on any airplane.

Alternative Methods of Compliance

    (f) In accordance with 14 CFR 39.19, the Manager, Seattle ACO, 
FAA, is authorized to approve alternative methods of compliance for 
this AD.

    Issued in Renton, Washington, on February 5, 2004.
Kevin M. Mullin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 04-3132 Filed 2-12-04; 8:45 am]
BILLING CODE 4910-13-P