[Federal Register Volume 70, Number 11 (Tuesday, January 18, 2005)]
[Proposed Rules]
[Pages 2826-2829]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-900]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2005-20024; Directorate Identifier 2004-NM-66-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 747-200C and 747-200F 
Series Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (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 747-200C and 747-200F series airplanes. This 
proposed AD would require repetitive inspections for cracking of the 
left and right C-3 frame upper closure fittings of the nose cargo door, 
and corrective actions if necessary. This proposed AD also provides an 
optional modification that, if done, would terminate inspections in 
certain areas. This proposed AD is prompted by reports indicating that 
fatigue cracking was found in the inboard flange above the flight deck 
floor on the C-3 frame upper closure fittings of the nose cargo door. 
We are proposing this AD to detect and correct cracking of the C-3 
frame upper closure fittings, which could extend and result in rapid 
depressurization of the airplane.

DATES: We must receive comments on this proposed AD by March 4, 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.
    For service information identified in this proposed AD, contact 
Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124-
2207.
    You can examine the contents of this AD docket on the Internet at 
http://dms.dot.gov, or in person 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: Ivan Li, Aerospace Engineer, Airframe 
Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind 
Avenue, SW., Renton, Washington 98055-4056; telephone (425) 917-6437; 
fax (425) 917-6590.

SUPPLEMENTARY INFORMATION:

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-2005-20024; 
Directorate Identifier 2004-NM-66-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

[[Page 2827]]

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 can review DOT's 
complete Privacy Act Statement in the Federal Register published on 
April 11, 2000 (65 FR 19477-78), or you can visit http://dms.dot.gov.

Examining the Docket

    You can 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 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 reports indicating that fatigue cracking was found 
in the inboard flange above the flight deck floor on the C-3 frame 
upper closure fittings of the nose cargo door on Boeing Model 747-200F 
series airplanes. The affected airplanes had accumulated approximately 
20,000 to 23,500 total flight cycles. While cracks have been found 
previously in the C-3 frame upper closure fittings, these reports were 
of cracks in the inboard flange of a fitting. This condition, if not 
corrected, could result in the cracks extending, which could result in 
rapid depressurization of the airplane.
    The C-3 frame upper closure fittings of the nose cargo door on 
Model 747-200C series airplanes are identical to those on Model 747-
200F series airplanes. Therefore, these airplanes may be subject to the 
same unsafe condition.

Relevant Service Information

    We have reviewed Boeing Alert Service Bulletin 747-53A2495, dated 
December 18, 2003. The service bulletin describes procedures for 
performing a detailed visual inspection for cracking of the C-3 frame 
upper closure fittings, including the flight deck floor tang, and 
corrective actions if necessary. The corrective actions include 
repairing, or replacing the fitting with a new fitting. The service 
bulletin describes procedures for repairs; however, if you find 
cracking that is outside certain limits, the service bulletin 
recommends that you contact Boeing for instructions for repairing the 
upper closure fitting, or replacing it with a new fitting. The 
compliance times for the initial inspection vary depending on the 
number of flight cycles that the airplane has accumulated as of the 
date of the initial release of the service bulletin (December 18, 
2003), and whether certain modifications have been accomplished. 
Accomplishing the actions specified in the service information is 
intended to adequately address the unsafe condition.
    The service bulletin also describes procedures for modifying the 
upper closure fittings. This modification involves doing an open-hole 
high frequency eddy current (HFEC) inspection for cracking of certain 
fastener holes, repairing if necessary, cold-working uncracked fastener 
holes, and installing new fasteners. If you do this modification, you 
do not need to continue inspecting the upper part of the closure 
fitting, though you must continue to inspect the flight deck floor 
tang.

Other Relevant Rulemaking

    We previously issued AD 91-11-01, amendment 39-6997 (56 FR 22306, 
May 15, 1991). That AD requires repetitive inspections for cracking of 
the frame structure and skin in the fuselage Section 41, and repair if 
necessary. That AD refers to Boeing Alert Service Bulletin 747-53A2265, 
Revision 7, dated January 25, 1990, as the appropriate source of 
service information for the required actions. That AD also states that 
installing new, improved body frame structure in accordance with Boeing 
Service Bulletin 747-53-2272, dated January 12, 1987, constitutes 
terminating action for the required repetitive inspections for the 
structure replaced and other adjacent structure.

Explanation of Compliance Times

    Paragraph (f) of this proposed AD refers to Boeing Alert Service 
Bulletin 747-53A2495, Figure 1 (for Group 1 and 2 airplanes) or Figure 
2 (for Group 3 and 4 airplanes), as applicable, as the source for the 
compliance time for the initial inspection required by that paragraph 
(except as discussed under ``Differences Between the Proposed AD and 
Service Bulletin''). For airplanes in Groups 1 and 2 in Boeing Alert 
Service Bulletin 747-53A2495, the compliance threshold for the initial 
inspection is based on whether the Zone 7 modification in accordance 
with Boeing Service Bulletin 747-53-2272 (the optional terminating 
action provided by AD 91-11-01) has been accomplished. If that 
modification has not been accomplished, the service bulletin specifies 
that the inspection in Boeing Alert Service Bulletin 747-53A2495 must 
be accomplished at the same time as the next scheduled inspection in 
accordance with Boeing Alert Service Bulletin 747-53A2265 (which is 
currently required by AD 91-11-01). If the Zone 7 modification in 
accordance with Boeing Service Bulletin 747-53-2272 has been 
accomplished, the service bulletin specifies a compliance threshold of 
3,000 flight cycles after the Zone 7 modification was installed. If the 
applicable threshold has passed, the service bulletin provides a grace 
period ranging from 250 to 1,000 flight cycles after the initial 
release of Boeing Alert Service Bulletin 747-53A2495, depending on the 
number of flight cycles the airplane has accumulated as of the initial 
release of that service bulletin.
    For airplanes in Groups 3 and 4, the service bulletin specifies a 
compliance time of prior to the accumulation of 16,000 total flight 
cycles, or within 1,000 flight cycles after the initial release of 
Boeing Alert Service Bulletin 747-53A2495, whichever is later.

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 the actions in Boeing Alert Service Bulletin 747-53A2495, 
described previously, except as discussed under ``Differences Between 
the Proposed AD and Service Bulletin.''

Differences Between the Proposed AD and Service Bulletin

    Boeing Alert Service Bulletin 747-53A2495 specifies that you may 
contact the manufacturer for instructions on how to replace or repair 
any cracked upper closure fitting, but this proposed AD would require 
you to replace or repair any cracked upper closure fitting in one of 
the following ways:
     Using a method that we approve; or
     Using data that meet the certification basis of the 
airplane that have been approved by an Authorized Representative for 
the Boeing Delegation Option Authorization Organization who has been 
authorized by the FAA to make those findings.
    Where Boeing Alert Service Bulletin 747-53A2495 specifies 
compliance times relative to the date of the initial release of the 
service bulletin, this proposed AD would require compliance relative to 
the effective date of the AD.
    Boeing Alert Service Bulletin 747-53A2495 provides the following 
information in Note 4 of the

[[Page 2828]]

Accomplishment Instructions: ``For the purposes of this service 
bulletin, do not count flight-cycles with a cabin pressure differential 
of 2.0 [pounds per square inch (psi)] or less. However, any flight-
cycle with momentary spikes in cabin pressure differential above 2.0 
psi must be included as a full-pressure flight-cycle. Cabin pressure 
records must be maintained for each airplane. Fleet averaging of cabin 
pressure is not allowed.'' We have determined that an adjustment of 
flight cycles due to a lower cabin differential pressure is not 
substantiated and will not be allowed for use in determining the flight 
cycle threshold for this proposed AD.

Clarification of Inspection Terminology

    In this proposed AD, the ``detailed visual inspection'' specified 
in Boeing Alert Service Bulletin 747-53A2495 is referred to as a 
``detailed inspection.'' We have included the definition for a detailed 
inspection in a note in the proposed AD.

Costs of Compliance

    This proposed AD would affect about 78 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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                                               Average
                                      Work      labor                                                Number of U.S.-
              Action                 hours     rate per          Parts          Cost per airplane      registered                 Fleet cost
                                                 hour                                                   airplanes
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Inspection.......................          2        $65  None................  $130, per                          20  $2,600, per inspection cycle.
                                                                                inspection cycle.
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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 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-2005-20024; Directorate Identifier 2004-NM-
66-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this AD action by March 4, 2005.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to all Boeing Model 747-200C and 747-200F 
series airplanes, certificated in any category.

Unsafe Condition

    (d) This AD was prompted by a report that a fatigue crack was 
found in the inboard flange of the left C-3 frame upper closure 
fitting above the flight deck floor. We are issuing this AD to 
detect and correct cracking of the C-3 frame upper closure fittings, 
which could extend and result in rapid depressurization 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.

Repetitive Inspections

    (f) Do a detailed inspection of the left and right C-3 frame 
upper closure fittings of the nose cargo door, including the flight 
deck floor tang, according to the Accomplishment Instructions of 
Boeing Alert Service Bulletin 747-53A2495, dated December 18, 2003. 
Do the initial inspection at the applicable compliance time 
specified in Figure 1 (Group 1 and 2 airplanes) or 2 (Group 3 and 4 
airplanes) of the service bulletin, as applicable; except, where the 
service bulletin specifies a compliance time relative to the date of 
the initial release of the service bulletin, this AD requires 
compliance relative to the effective date of this AD. Repeat the 
inspection thereafter at intervals not to exceed 3,000 flight 
cycles, except as provided by paragraph (h) 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.''

Repair/Replacement

    (g) If any cracking is found during any inspection required by 
this AD: Before further flight, do applicable repairs or replace the 
fitting with a new fitting, according to the Accomplishment 
Instructions of Boeing Alert Service Bulletin 747-53A2495, dated 
December 18, 2003; except, where the bulletin specifies to contact 
Boeing for appropriate action, before further flight, repair in 
accordance with a method approved

[[Page 2829]]

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 
Delegation Option Authorization Organization who the Manager, 
Seattle ACO, has authorized to make this finding. For a repair 
method to be approved by the Manager, Seattle ACO, as required by 
this paragraph, the Manager's approval letter must specifically 
reference this AD.

Optional Modification

    (h) Doing all actions associated with the modification of the 
upper closure fitting, including performing an open-hole high 
frequency eddy current inspection for cracking of certain fastener 
holes and all applicable corrective actions; according to Figure 4 
of the Accomplishment Instructions of Boeing Alert Service Bulletin 
747-53A2495, dated December 18, 2003; terminates the repetitive 
inspections of the upper part of the upper closure fitting required 
by paragraph (f) of this AD. However, inspections of the flight deck 
floor tang must continue, as required by paragraph (f) of this AD.

    Note 2: There is no terminating action available at this time 
for the inspections of the flight deck floor tang required by 
paragraph (f) of this AD.

No Threshold Adjustment

    (i) While Note 4 of the Accomplishment Instructions of Boeing 
Alert Service Bulletin 747-53A2495, dated December 18, 2003, 
provides for adjusting the flight cycle threshold specified in the 
service bulletin by not counting flight cycles with a cabin pressure 
differential of 2.0 pounds per square inch or less, this AD does not 
allow this adjustment.

Alternative Methods of Compliance (AMOCs)

    (j)(1) The Manager, Seattle ACO, has the authority to approve 
AMOCs for this AD, if requested in accordance with 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 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 January 7, 2005.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 05-900 Filed 1-14-05; 8:45 am]
BILLING CODE 4910-13-P