[Federal Register Volume 69, Number 188 (Wednesday, September 29, 2004)]
[Proposed Rules]
[Pages 58101-58103]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-21821]



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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2004-19200; Directorate Identifier 2003-NM-195-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 747-100, -100B, -100B SUD, 
-200B, -200C, -200F, and -300 Series Airplanes; and Model 747SP and 
747SR Series Airplanes; Equipped with Pratt & Whitney JT9D-3, and -7 
(except -70) Series Engines or General Electric CF6-50 Series Engines 
with Modified JT9D-7 Inboard Struts

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 airplanes listed above. This proposed AD would 
require repetitive detailed inspections of the midspar web of the 
inboard and/or outboard struts for cracking, disbonding, or buckling; 
repetitive detailed inspections of the midspar stiffeners for any crack 
or fracture; related investigative actions; and corrective actions, if 
necessary. This proposed AD is prompted by reports of cracking in the 
midspar web. We are proposing this AD to detect and correct cracking in 
the midspar assembly, which could result in the loss of the midspar 
assembly load path, and could, combined with the loss of the Nacelle 
Station 180 bulkhead load path, lead to the separation of the engine 
from the airplane.

DATES: We must receive comments on this proposed AD by November 15, 
2004.

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> By 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.
    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 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: 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: 

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-2004-19200; 
Directorate Identifier 2003-NM-195-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 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.
    We are reviewing the writing style we currently use in regulatory 
documents. 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 can 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 reports of cracking in the midspar web, and one 
report of a fractured stiffener on certain Boeing Model 747 series 
airplanes with Pratt & Whitney Model JT9D-7 series engines. The 
cracking/fracture was caused by fatigue and sonic-induced vibration. 
This condition, if not detected and corrected, could result in the loss 
of the midspar assembly load path, and could, combined with the loss of 
the Nacelle Station 180 bulkhead load path, lead to the separation of 
the engine from the airplane.

Similar Design

    The subject area on Boeing Model 747 series airplanes with Pratt & 
Whitney Model JT9D-3 series engines or General Electric Model CF6-50 
series engines with modified JT9D-7 inboard struts is identical to that 
on the affected Model 747 series airplanes with JT9D-7 series engines. 
Therefore, those Model 747 series airplanes with JT9D-3 series engines 
or CF6-50 series engines with modified JT9D-7 inboard struts may be 
subject to the same unsafe condition revealed on the Model 747 series 
airplanes with JT9D-7 series engines.

Relevant Service Information

    We have reviewed Boeing Alert Service Bulletin 747-54A2219, dated 
September 4, 2003, which describes the following procedures:

[[Page 58102]]

    <bullet> For Group 1 and 2 airplanes: Performing repetitive 
detailed inspections of the midspar web of the inboard struts for 
cracking, disbonding, or buckling.
    <bullet> For Group 1 airplanes: Performing repetitive detailed 
inspections of the midspar web of the outboard struts for cracking, 
disbonding, or buckling.
    <bullet> For Group 1 and 2 airplanes: Performing repetitive 
detailed inspections of the midspar stiffeners of the inboard struts 
for any crack or fracture.
    <bullet> For Group 1 airplanes: Performing repetitive detailed 
inspections of the midspar stiffeners of the outboard struts for any 
crack or fracture.
    <bullet> For Group 1 and 2 airplanes: Performing related 
investigative actions. The related investigative actions include 
performing a high frequency eddy current (HFEC) or penetrant inspection 
for cracking of any buckle found on the midspar web and performing an 
ultrasonic inspection for disbonding of any buckle found on the midspar 
web.
    <bullet> For Group 1 and 2 airplanes: Performing corrective 
actions, if necessary. The corrective actions include repairing the 
midspar web or replacing the midspar stiffener with a new midspar 
stiffener (includes an HFEC inspection of the stiffener hole for any 
crack), and contacting Boeing if any crack is found in the stiffener 
hole or if any buckle is found that does not have any cracking and the 
web is not disbonded.
    We have determined that accomplishing 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 detailed inspections of the midspar web of the 
inboard and/or outboard struts for cracking, disbonding, or buckling; 
repetitive detailed inspections of the midspar stiffeners for any crack 
or fracture; related investigative actions; 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 ``Differences Between the Proposed AD and the Service 
Bulletin.''

Differences Between the Proposed AD and the Service Bulletin

    Operators should note that, although the service bulletin specifies 
that the manufacturer may be contacted for disposition of certain 
repair conditions, this proposal would require the repair of those 
conditions 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.

Costs of Compliance

    This proposed AD would affect about 78 airplanes of U.S. registry 
and 228 airplanes worldwide. The proposed actions would take about 6 to 
13 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 between $30,420 and $65,910, or between $390 and $845 
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-2004-19200; Directorate Identifier 2003-NM-
195-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this AD action by November 15, 2004.

Affected ADs

    (b) None.
    Applicability: (c) This AD applies to Boeing Model 747-100, -
100B, -100B SUD, -200B, -200C, -200F, and -300 series airplanes; and 
Model 747SP and 747SR series airplanes; certificated in any 
category; equipped with Pratt & Whitney JT9D-3, and -7 (except-70) 
series engines or General Electric CF6-50 series engines with 
modified JT9D-7 inboard struts; as listed in Boeing Alert Service 
Bulletin 747-54A2219, dated September 4, 2003.

Unsafe Condition

    (d) This AD was prompted by reports of cracking in the midspar 
web. We are issuing this AD to detect and correct cracking in the 
midspar assembly, which could result in the loss of the midspar 
assembly load path, and could, combined with the loss of the Nacelle 
Station 180 bulkhead load path, lead to the separation of the engine 
from 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.

Compliance Times

    (f) Within 18 months after the effective date of this AD, do the 
actions in paragraphs (g) and (h) of this AD, as applicable. Repeat 
the actions thereafter at intervals not to exceed 1,200 flight 
cycles.

Inboard Strut Midspar Inspection

    (g) For Group 1 and 2 airplanes specified in paragraph 1.A.1. of 
Boeing Alert Service Bulletin 747-54A2219, dated September 4, 2003: 
Perform a detailed inspection of the midspar web of the inboard 
struts for cracking, disbonding, or buckling; a detailed inspection 
of the midspar stiffeners for any crack or fracture; related 
investigative actions; and any applicable corrective actions; in 
accordance with ``Part 1'' of the Work Instructions of Boeing Alert 
Service Bulletin 747-54A2219, dated September 4, 2003; except as 
required by paragraph (i) of this AD. Perform any related 
investigative actions and any applicable corrective actions before 
further flight.

Outboard Strut Midspar Inspection

    (h) For Group 1 airplanes specified in paragraph 1.A.1. of 
Boeing Alert Service

[[Page 58103]]

Bulletin 747-54A2219, dated September 4, 2003: Perform a detailed 
inspection of the midspar web of the outboard struts for cracking, 
disbonding, or buckling; a detailed inspection of the midspar 
stiffeners for any crack or fracture; related investigative actions; 
and any applicable corrective actions; in accordance with ``Part 2'' 
of the Work Instructions of Boeing Alert Service Bulletin 747-
54A2219, dated September 4, 2003; except as required by paragraph 
(i) of this AD. Perform any related investigative actions and any 
applicable corrective actions before further flight.

Contact the FAA/Designated Engineering Representative

    (i) Where Boeing Alert Service Bulletin 747-54A2219, dated 
September 4, 2003, specifies to contact Boeing for appropriate 
action: 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.

Alternative Methods of Compliance (AMOCs)

    (j)(1) The Manager, Seattle 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 a 
Boeing Company Designated Engineering Representative who has been 
authorized by the Manager, Seattle ACO, to make those findings. For 
a repair method to be approved, the approval must specifically refer 
to this AD.


    Issued in Renton, Washington, on September 21, 2004.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 04-21821 Filed 9-28-04; 8:45 am]
BILLING CODE 4910-13-P