[Federal Register Volume 70, Number 171 (Tuesday, September 6, 2005)]
[Proposed Rules]
[Pages 52945-52947]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-17609]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2005-22289; Directorate Identifier 2005-NM-101-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 747-100, 747-100B, 747-
200B, 747-200C, 747-200F, 747-400F, 747SR, and 747SP 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 747-100, 747-100B, 747-200B, 747-200C, 747-
200F, 747-400F, 747SR, and 747SP series airplanes, without a stretched 
upper deck or stretched upper deck modification. This proposed AD would 
require detailed and high-frequency eddy current inspections for cracks 
at the outboard ends of each affected tension tie and of the 
surrounding structure, and related investigative and corrective actions 
if necessary. This proposed AD results from a report of a crack in the 
tension tie at the body station 820 frame connection, and cracks found 
on the Boeing 747SR fatigue-test airplane in both the tension ties and 
frames at the tension tie to frame connections at body stations 800, 
820, and 840. We are proposing this AD to find and fix cracks in the 
tension ties, which could lead to cracks in the skin and body frame and 
result in rapid in-flight depressurization 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.
     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.
     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.
    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-
2005-22289; Directorate Identifier 2005--NM-101-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 a report indicating that, during routing 
maintenance on a 747-200F series airplane, one operator found a crack 
in the tension tie at the body station (STA) 820 frame

[[Page 52946]]

connection. The crack was 0.125 inch long and located at a fastener 
hole. The manufacturer then inspected the 747SR fatigue-test airplane 
and found similar cracks in both the tension ties and frames at the 
tension ties to the frame connection. The cracks were found at STAs 
800, 820, and 840 at 40,000 total flight cycles (20,000 operating 
cycles, 20,000 test cycles). Cracks in the frames were up to 1.25 
inches long, and cracks in the tension ties were up to 0.20 inch long. 
Cracks in the tension ties, if not detected and corrected before they 
reach critical crack lengths, could lead to cracks in the skin and body 
frame and result in rapid in-flight depressurization of the airplane.

Other Relevant Rulemaking

    On September 4, 1984, we issued AD 84-19-01, amendment 39-4913 (49 
FR 35365, September 17, 1984) for Boeing Model 747 series airplanes. 
That AD was prompted by a report of a crack that occurred during 
fatigue testing. That AD requires repetitive close visual inspections 
for cracks of the tension tie at STA 760 for certain airplanes and at 
STA 780 for certain other airplanes, and repair if necessary. We issued 
that AD to detect cracks and prevent failure of the frame to tension 
tie joint structure. The airplanes in the applicability of AD 84-19-01 
would also be subject to the requirements of this proposed AD.
    On June 14, 1994, we issued AD 94-13-06, amendment 39-8946 (59 FR 
32879, June 27, 1994), for certain Boeing Model 747 series airplanes. 
That AD requires inspections to detect cracking in certain fuselage 
upper deck tension ties, and repair or modification of any cracked 
tension ties. We issued that AD to prevent failure of two or more 
tension ties and the resultant rapid decompression of the airplane. The 
airplanes in the applicability of AD 94-13-06 would also be subject to 
the requirements of this proposed AD.
    On March 24, 2004, we issued AD 2004-07-22, amendment 39-13566 (69 
FR 18250, April 7, 2004), for all Boeing Model 747 series airplanes. 
That AD requires revising the FAA-approved maintenance or inspection 
program to include repetitive inspections for discrepancies of various 
structural significant items (SSIs); as listed in Boeing Document No. 
D6-35022, ``Supplemental Structural Inspection Document (SSID),'' 
Revision G, dated December 2000 (referred to after this as ``the 
SSID''); and repair if necessary.

Relevant Service Information

    We have reviewed Boeing Special Attention Service Bulletin 747-53-
2502, dated April 21, 2005. The service bulletin describes procedures 
for doing repetitive detailed and high-frequency eddy current (HFEC) 
inspections for cracks at the outboard ends of each affected tension 
tie and of the surrounding structure. If any cracking is found, the 
service bulletin describes procedures for related investigative and 
corrective actions. These actions include doing all applicable repairs 
and doing further HFEC inspections of certain fastener holes until the 
inspection indicates that the repair has removed all cracking. If the 
cracking exceeds certain limits defined in the service bulletin, or if 
the area cannot be repaired without exceeding certain limits, or if the 
discrepancy is at certain locations defined in the service bulletin, 
the corrective action is contacting Boeing for repair instructions.

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 the Service Bulletin.''
    Certain actions in this proposed AD are alternative methods of 
compliance (AMOCs) for certain actions in the ADs referenced below. All 
provisions of the referenced ADs, including applicable post-
modification inspection thresholds, remain fully applicable and must be 
complied with.
     Repairs of the aft tension tie channels in accordance with 
this proposed AD would be AMOCs to the repair requirements of paragraph 
A. of AD 84-19-01, and paragraphs (a)(2) and (b)(2) of AD 94-13-06.
     The inspection requirements of this proposed AD would be 
AMOCs for the post-modification inspection requirements of paragraph B. 
of AD 84-19-01, and paragraph (b) of AD 94-13-06.
     The inspection requirements of this proposed AD would be 
AMOCs for the corresponding requirements of paragraphs (c) and (d) of 
AD 2004-07-22 for the inspections of SSI item F-19A of the SSID in the 
area addressed by this proposed AD.

Difference Between the Proposed AD and the Service Bulletin

    The service bulletin specifies that you may contact the 
manufacturer for instructions on how to repair certain conditions, but 
this proposed AD would require you to repair those conditions in one of 
the following ways:
     Using a method that we approve; or
     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.
    This difference has been coordinated with the manufacturer.

Interim Action

    We consider this proposed AD interim action. The manufacturer is 
currently developing a modification that will address the unsafe 
condition identified in this AD. Once this modification is developed, 
approved, and available, we may consider additional rulemaking.

Costs of Compliance

    There are about 458 airplanes of the affected design in the 
worldwide fleet. This proposed AD would affect about 141 airplanes of 
U.S. registry. The proposed inspections would take about 8 work hours 
per airplane, per tension tie location. There are between 8 and 12 
tension tie locations on each airplane, depending on the airplane's 
configuration. The average labor rate is $65 per work hour. Based on 
these figures, the estimated cost of the proposed AD for U.S. operators 
is between $586,560 and $879,840, or between $4,160 and $6,240 per 
airplane, per inspection cycle.

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.

[[Page 52947]]

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-2005-22289; Directorate Identifier 2005-NM-
101-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 747-100, 747-100B, 747-200B, 
747-200C, 747-200F, 747-400F, 747SR, and 747SP series airplanes, 
certificated in any category; without a stretched upper deck or 
stretched upper deck modification; as identified in Boeing Special 
Attention Service Bulletin 747-53-2502, dated April 21, 2005.

Unsafe Condition

    (d) This AD results from a report of a crack in the tension tie 
at the body station 820 frame connection, and cracks found on the 
Boeing 747SR fatigue-test airplane in both the tension ties and 
frames at the tension tie to frame connections at body stations 800, 
820, and 840. We are issuing this AD to find and fix cracks in the 
tension ties, which could lead to cracks in the skin and body frame 
and result in rapid in-flight 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 and Corrective Actions

    (f) At the applicable time in paragraph (f)(1) or (f)(2) of this 
AD: Do detailed and high-frequency eddy current inspections for 
cracks at the outboard ends of each affected tension tie and of the 
surrounding structure. If any cracking is found: Before further 
flight, do all applicable corrective and related investigative 
actions. Do all actions in accordance with the Accomplishment 
Instructions of Boeing Special Attention Service Bulletin 747-53-
2502, dated April 21, 2005. Where the service bulletin specifies to 
contact Boeing for repair instructions: Before further flight, 
repair the area using a method approved in accordance with paragraph 
(g) of this AD.
    (1) For airplanes identified in the service bulletin as Group 1, 
3, and 6 airplanes: Do the first inspections before the accumulation 
of 20,000 total flight cycles, or within 1,000 flight cycles after 
the effective date of this AD, whichever occurs later; and repeat 
the inspections thereafter at intervals not to exceed 4,000 flight 
cycles.
    (2) For airplanes identified in the service bulletin as Group 2, 
4, and 5 airplanes: Do the first inspections before the accumulation 
of 17,000 total flight cycles, or within 1,000 flight cycles after 
the effective date of this AD, whichever occurs later; and repeat 
the inspections thereafter at intervals not to exceed 3,000 flight 
cycles.

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.
    (3) Certain actions required by paragraph (f) of this AD are 
AMOCs for certain requirements in the ADs identified in paragraphs 
(g)(1)(i), (g)(2)(ii), and (g)(3)(iii) of this AD. All provisions of 
the referenced ADs, including applicable post-modification 
inspection thresholds, remain fully applicable and must be complied 
with.
    (i) Repairs of the aft tension tie channels done in accordance 
with this AD are AMOCs for the repair requirements of paragraph A. 
of AD 84-19-01, amendment 39-4913, and paragraphs (a)(2) and (b)(2) 
of AD 94-13-06, amendment 39-8946.
    (ii) The inspection requirements of this AD are AMOCs for the 
post modification inspection requirements of paragraph B. of AD 84-
19-01, and paragraph (b) of AD 94-13-06.
    (iii) The inspection requirements of this AD are AMOCs for the 
inspections of structural significant item (SSI) F-19A of Boeing 
Supplemental Structural Inspection Document D6-35022, Revision G, 
dated December 2000, as required by paragraphs (c) and (d) of AD 
2004-07-22, amendment 39-13566.

    Issued in Renton, Washington, on August 29, 2005.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 05-17609 Filed 9-2-05; 8:45 am]
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