[Federal Register Volume 70, Number 171 (Tuesday, September 6, 2005)]
[Proposed Rules]
[Pages 52943-52945]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-17608]



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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2005-22288; Directorate Identifier 2005-NM-132-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 747-400 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 certain Boeing Model 747-400 series airplanes. This proposed AD 
would require doing a conductivity test of the upper deck floor beam at 
station 400 to identify the floor beam material. If the floor beam is 
manufactured from 7050 aluminum alloy, this proposed AD would also 
require inspecting the upper deck floor beam and certain fastener holes 
at the floor beam upper chord for cracking; repairing any cracking if 
necessary; and doing a preventative modification. This proposed AD 
results from several reports indicating that fatigue cracking was found 
in upper deck floor beams made from 7050 aluminum alloy. We are 
proposing this AD to find and fix cracking in the upper deck floor 
beam, which could extend and sever the floor beam. A severed floor beam 
could result in loss of controllability and rapid decompression of the 
airplane.

DATES: We must receive comments on this proposed AD by October 21, 
2005.

ADDRESSES: Use one of the following addresses to submit comments on 
this proposed AD.
    <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 the service information identified in this 
proposed AD.

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 relevant written data, views, or 
arguments regarding this proposed AD. Include the docket number ``FAA-
2005-22288; Directorate Identifier 2005-NM-132-AD'' at the beginning 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 received 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.

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 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 Docket Management System 
receives them.

Discussion

    We have received several reports indicating that fatigue cracking 
was found in upper deck floor beams made from 7050 aluminum alloy, on 
Boeing Model 747-100, -200F, and -300 series airplanes. The upper deck 
floor beams on most Model 747-400 series airplanes are made from 2024 
aluminum alloy; however, the manufacturer has informed us that the 
upper deck floor beam at station 400 on some Model 747-400 series 
airplanes was made from 7050 aluminum alloy. Investigation revealed 
that floor beams made from 7050 aluminum alloy are less resistant to 
fatigue cracking than floor beams made from 2024 aluminum alloy. 
Cracking in the upper deck floor beam, if not detected and corrected, 
could extend and sever the floor beam. A severed floor beam could 
result in loss of controllability and rapid decompression of the 
airplane.
    Upper deck floor beams made from 7050 aluminum alloy at station 400 
on certain Model 747-400 series airplanes are similar to those on the 
affected Model 747-100, -200F, and -300 series airplanes. Therefore, 
all these models may be subject to the same unsafe condition.

Other Related Rulemaking

    On August 30, 2002, we issued AD 2002-18-04, amendment 39-12878 (67 
FR 57510, September 11, 2001), applicable to certain Boeing Model 747-
100, 747-100B, 747-100B SUD, 747-200B, 747-300, 747SR, and 747SP series 
airplanes. That AD requires one-time inspections for cracking in 
certain upper deck floor beams and follow-on actions. AD 2002-18-04 
does not affect the requirements of this proposed AD.
    On April 4, 2005, we issued AD 2005-07-21, amendment 39-14046 (70 
FR 18277, April 11, 2005), applicable to all Boeing Model 747-200F and 
-200C series airplanes. That AD requires repetitive detailed 
inspections or a one-time open-hole high frequency eddy current 
inspection to detect cracking of certain areas of the upper deck floor 
beams, and corrective actions if necessary. That AD also requires one-
time inspections for cracking of the web, upper chord, and strap of the 
upper deck floor beams, and modification or repair of the upper deck 
floor beams. AD 2005-07-21 does not affect the requirements of this 
proposed AD.

Relevant Service Information

    We have reviewed Boeing Alert Service Bulletin 747-53A2509, dated 
June 9, 2005. The service bulletin describes procedures for doing a 
conductivity test of the upper deck floor beam at station 400 to 
identify the floor beam material, and if the floor beam is manufactured 
from 7050 aluminum alloy, accomplishing the following actions:
    <bullet> Doing a one-time detailed inspection of the floor beam for 
cracking.

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    <bullet> Doing a one-time high frequency eddy current inspection 
(HFEC) of certain fastener holes at the floor beam upper chord for 
cracking.
    <bullet> Contacting the manufacturer for repair instructions if any 
cracking is found during the detailed inspection of the floor beam.
    <bullet> Oversizing fastener holes if any cracking is found during 
the HFEC inspection of certain fastener holes; and contacting the 
manufacturer for repair data if a certain edge margin cannot be 
maintained when oversizing the fastener holes.
    <bullet> Contacting the manufacturer for instructions on doing a 
preventative modification.
    <bullet> Reporting inspection results to the manufacturer.
    Accomplishing the actions specified in the service information is 
intended to 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. For this reason, we are proposing this AD, 
which would require accomplishing the actions specified in the service 
information described previously, except as discussed under 
``Difference Between the Proposed AD and Service Bulletin.'' The 
proposed AD would also require sending the inspection results to the 
manufacturer.

Difference Between the Proposed AD and Service Bulletin

    The service bulletin specifies to contact the manufacturer for 
instructions on how to repair certain conditions, but this proposed AD 
would require repairing 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 123 airplanes of the affected design in the 
worldwide fleet. This proposed AD would affect about 17 airplanes of 
U.S. registry. The proposed conductivity test would take about 2 work 
hours per airplane, at an average labor rate of $65 per work hour. 
Based on these figures, the estimated cost of the proposed AD for U.S. 
operators is $2,210, or $130 per airplane.

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 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-2005-22288; Directorate Identifier 2005-NM-
132-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by October 
21, 2005.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Boeing Model 747-400 series airplanes, 
certificated in any category; as identified in Boeing Alert Service 
Bulletin 747-53A2509, dated June 9, 2005.

Unsafe Condition

    (d) This AD results from several reports indicating that fatigue 
cracking was found in upper deck floor beams made from 7050 aluminum 
alloy. We are issuing this AD to find and fix cracking in the upper 
deck floor beam, which could extend and sever the floor beam. A 
severed floor beam could result in loss of controllability and rapid 
decompression 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.

Conductivity Test

    (f) Before an airplane has accumulated 15,000 total flight 
cycles, do a conductivity test of the upper deck floor beam at 
station 400 to identify the floor beam material, in accordance with 
Part II of the Accomplishment Instructions of Boeing Alert Service 
Bulletin 747-53A2509, dated June 9, 2005. If the upper deck floor 
beam is not made from 7050 aluminum alloy, no further action is 
required by this AD. If the upper deck floor beam is made from 7050 
aluminum alloy, do the actions specified in paragraphs (f)(1), 
(f)(2), and (f)(3) of this AD.

Inspections and Corrective Actions, if Applicable

    (1) Before an airplane has accumulated 15,000 total flight 
cycles, do a detailed inspection of the upper deck floor beam at 
station 400 for cracking, and do a high frequency eddy current 
(HFEC) inspection of certain fastener holes at the floor beam upper 
chord for cracking, in accordance with Part III of the 
Accomplishment Instructions of Boeing Alert Service Bulletin 747-
53A2509, dated June 9, 2005. If any cracking is found during the 
HFEC inspection of certain fasteners holes, before further flight, 
repair

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the cracking in accordance with Figure 3 of the service bulletin. If 
any cracking is found during the detailed inspection of the upper 
deck floor beam, and the service bulletin specifies to contact 
Boeing for appropriate action: Before further flight, repair the 
cracking using a method approved in accordance with paragraph (g) of 
this AD.

Reporting Requirement

    (2) Submit a report of the findings (both positive and negative) 
of the inspections required by paragraph (f)(1) of this AD to Boeing 
Commercial Airplanes; Attention: Manager, Airline Support; P.O. Box 
3707 MC 04-ER; Seattle, Washington 98124-2207; fax (425) 266-5562; 
at the applicable time specified in paragraph (f)(2)(i) or 
(f)(2)(ii) of this AD. The report must include the inspection 
results, a description of any discrepancies found, the airplane 
serial number, and the number of landings and flight hours on the 
airplane. Under the provisions of the Paperwork Reduction Act of 
1980 (44 U.S.C. 3501 et seq.), the Office of Management and Budget 
(OMB) has approved the information collection requirements contained 
in this AD and has assigned OMB Control Number 2120-0056.
    (i) If the inspections were done after the effective date of 
this AD: Submit the report within 30 days after the inspection.
    (ii) If the inspections were done prior to the effective date of 
this AD: Submit the report within 30 days after the effective date 
of this AD.

Preventative Modification

    (3) Before an airplane has accumulated 20,000 total flight 
cycles, do a preventative modification using a method approved in 
accordance with paragraph (g) of this AD.

Alternative Methods of Compliance (AMOCs)

    (g)(1) The Manager, Seattle Aircraft Certification Office (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) 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 Commercial Airplanes 
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 August 29, 2005.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 05-17608 Filed 9-2-05; 8:45 am]
BILLING CODE 4910-13-P