[Federal Register Volume 69, Number 151 (Friday, August 6, 2004)]
[Proposed Rules]
[Pages 47804-47806]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-17986]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2004-18786; Directorate Identifier 2004-NM-26-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 767-200, -300, and -300F 
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 certain Boeing Model 767-200, -300, and -300F series airplanes. 
This proposed AD would require repetitive high frequency eddy current 
inspections and detailed inspections of the left and right butt line 
(BL) 25 vertical chords for cracks, and corrective actions if 
necessary. This proposed AD is prompted by findings of cracks in the 
fillet radii of the left and right BL 25 vertical chords common to the 
nose wheel well bulkhead at station 287. We are proposing this AD to 
detect and correct cracks in the left and right BL 25 vertical chords, 
which could grow downward into a critical area that serves as a primary 
load path for the nose landing gear (NLG) and result in the collapse of 
the NLG during landing.

DATES: We must receive comments on this proposed AD by September 20, 
2004.

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: Suzanne Masterson, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
917-6441; 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-
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-2004-18786; 
Directorate Identifier 2004-NM-26-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 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 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.

[[Page 47805]]

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

    We have received a report of two operators finding cracks in the 
fillet radii of the left and right butt line (BL) 25 vertical chords, 
common to the nose wheel well bulkhead at station 287, on several 
Boeing Model 767-300 series airplanes. Stress corrosion was determined 
to have caused the cracks. This condition, if not corrected, could grow 
downward into a critical area that serves as a primary load path for 
the nose landing gear (NLG) and result in the collapse of the NLG 
during landing.

Relevant Service Information

    We have reviewed Boeing Alert Service Bulletin 767-53A0113, dated 
February 26, 2004. The service bulletin describes procedures for 
repetitive high frequency eddy current inspections (HFEC) and detailed 
inspections of the left and right BL 25 vertical chords common to the 
nose wheel well bulkhead at station 287 for cracks, and corrective 
actions if necessary. The corrective action includes repairing any 
damaged BL 25 vertical chord or contacting the manufacturer for repair 
instructions, as applicable. 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 HFEC inspections and detailed inspections of 
the left and right BL 25 vertical chords common to the nose wheel well 
bulkhead at station 287 for cracks, and corrective actions if 
necessary. The proposed AD would require you to use the service 
information described previously to perform these actions, except as 
discussed under ``Difference Between the Proposed AD and the Service 
Bulletin.''

Differences Between the Proposed AD and the Service Bulletin

    The service bulletin specifies that you may contact the 
manufacturer for instructions on repairing certain conditions. This 
proposed AD, however, would require you to repair those conditions 
using a method approved by the FAA, or with 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.

Clarification of Inspection Terminology

    In this proposed AD, the ``detailed visual inspection'' specified 
in the service bulletin is referred to as a ``detailed inspection.'' We 
have included the definition for a detailed inspection in a note in 
this proposed AD.

Clarification Between Proposed Rule and the Service Bulletin

    The service bulletin specifies a compliance time of 6 years in 
service, or within 18 months from the release date of the service 
bulletin. However, paragraph (g) of this proposed AD specifies the 
compliance time as the later of the following: (1) within 72 months 
since the date of issuance of the original Airworthiness Certificate or 
the date of issuance of the original Export Certificate of 
Airworthiness, or (2) within 18 months after the effective date of this 
AD. This decision is based on our determination that ``years in 
service'' may be interpreted differently by different operators. We 
find that our proposed terminology is generally understood within the 
industry and records will always exist that establish these dates with 
certainty.

Costs of Compliance

    This proposed AD would affect about 743 airplanes worldwide and 312 
airplanes of U.S. registry. The proposed actions would take about 8 
work hours per airplane, at an average labor rate of $65 per work hour. 
No parts are required. Based on these figures, the estimated cost of 
the proposed AD for U.S. operators is $162,240, or $520 per airplane, 
per inspection cycle.

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-2004-18786; Directorate Identifier 2004-NM-
26-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this AD action by September 20, 2004.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Boeing Model 767-200, -300, and -300F 
series airplanes, certificated in any category; as listed in Boeing 
Alert Service Bulletin 767-53A0113, dated February 26, 2004.

Unsafe Condition

    (d) This AD was prompted by findings of cracks in the fillet 
radii of the left and right

[[Page 47806]]

butt line (BL) 25 vertical chords common to the nose wheel well 
bulkhead at station 287. We are issuing this AD to detect and 
correct cracks in the left and right BL 25 vertical chords, which 
could grow downward into a critical area that serves as a primary 
load path for the nose landing gear (NLG) and result in the collapse 
of the NLG during landing.

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) The term ``service bulletin,'' as used in this AD, means the 
Accomplishment Instructions of Boeing Alert Service Bulletin 767-
53A0113, dated February 26, 2004.

Initial Inspections

    (g) At the later of the compliance times specified in paragraphs 
(g)(1) and (g)(2) of this AD: Do a high frequency eddy current 
inspection and a detailed inspection of the left and right BL 25 
vertical chords common to the nose wheel well bulkhead at station 
287 for cracks, in accordance with the service bulletin.
    (1) Within 72 months since the date of issuance of the original 
Airworthiness Certificate or the date of issuance of the original 
Export Certificate of Airworthiness.
    (2) Within 18 months after the effective date of this AD.

    Note 1: For the purposes of this AD, a detailed inspection is: 
``An intensive examination of a specific item, installation, or 
assembly to detect damage, failure, or irregularity. Available 
lighting is normally supplemented with a direct source of good 
lighting at an intensity deemed appropriate. Inspection aids such as 
mirror, magnifying lenses, etc., may be necessary. Surface cleaning 
and elaborate procedures may be required.''

No Cracks Found

    (h) For any BL 25 vertical chord in which no crack is found 
during any inspection required by paragraph (g) of this AD: 
Thereafter at intervals not to exceed 48 months, repeat the 
inspections required by paragraph (g) of this AD for any BL 25 
vertical chord that has not been repaired according to paragraph (i) 
or (j) of this AD.

Cracks Found: Extending Below Water Line (WL) 159

    (i) If any crack is found on any BL 25 vertical chord during any 
inspection required by paragraph (g) or (h) of this AD, and the 
crack extends below WL 159: Before further flight, repair 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 method to be approved, the 
approval must specifically reference this AD.

Cracks Found: Not Extending Below WL 159

    (j) If any crack is found in any BL 25 vertical chord during any 
inspection required by paragraph (g) or (h) of this AD, and the 
crack does not extend below WL 159: Before further flight, repair 
any damaged BL 25 vertical chord in accordance with the service 
bulletin.

Repaired BL 25 Vertical Chords

    (k) Repair of any BL 25 vertical chord in accordance with 
paragraph (i) or (j) of this AD, as applicable, terminates the 
repetitive inspections required by paragraph (h) of this AD for the 
repaired vertical chord only. If both the left and right BL 25 
vertical chords are repaired as required by paragraph (i) or (j) of 
this AD, as applicable, no more work is required by this AD.

Alternative Methods of Compliance (AMOCs)

    (l)(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.
    (2) An AMOC that provides an acceptable level of safety may be 
used for any repair required by this AD, if it is approved by a 
Boeing Company Designated Engineering Representative who has been 
authorized by the Manager, Seattle ACO, to make such findings.

    Issued in Renton, Washington, on July 30, 2004.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 04-17986 Filed 8-5-04; 8:45 am]
BILLING CODE 4910-13-P