[Federal Register Volume 69, Number 214 (Friday, November 5, 2004)]
[Proposed Rules]
[Pages 64525-64530]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-24723]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2004-19535; Directorate Identifier 2004-NM-78-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 747-100, 747-100B, 747-
100B SUD, 747-200B, 747-300, 747SP, and 747SR Series Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to supersede an existing airworthiness 
directive (AD) for certain Boeing Model 747-100, 747-100B, 747-100B 
SUD, 747-200B, 747-300, 747SP, and 747SR series airplanes. That AD 
currently requires one-time inspections for cracking in certain upper 
deck floor beams and follow-on actions. This proposed AD would expand 
the existing inspection area, and would require inspecting fastener 
holes in certain areas of airplanes modified previously, and

[[Page 64526]]

taking corrective actions if necessary. This action also would define 
new sources for instructions for repairs and post-modification/repair 
inspections. This proposed AD is prompted by reports of fatigue 
cracking of the upper chord of certain upper deck floor beams. We are 
proposing this AD to find and fix cracking in certain upper deck floor 
beams, which could extend and sever floor beams adjacent to the body 
frame and result in rapid depressurization and loss of controllability 
of the airplane.

DATES: We must receive comments on this proposed AD by December 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.
     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. This docket 
number is FAA-2004-19535; the directorate identifier for this docket is 
2004-NM-78-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) 917-6432.

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-2004-19535; 
Directorate Identifier 2004-NM-78-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 our 
docket 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 the 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. 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

    On August 30, 2002, we issued AD 2002-18-04, amendment 39-12878 (67 
FR 57510, September 11, 2002), for certain Boeing Model 747-100, 747-
100B, 747-100B SUD, 747-200B, 747-300, 747SP, and 747SR series 
airplanes. That AD requires one-time inspections for cracking in 
certain upper deck floor beams and follow-on actions. That AD was 
prompted by reports of fatigue cracking on the left and right ends of 
the upper chord of the station (STA) 340 upper deck floor beam on 
several Boeing Model 747 series airplanes. We issued that AD to find 
and fix cracking in certain upper deck floor beams. Such cracking could 
extend and sever floor beams adjacent to the body frame and result in 
rapid depressurization and loss of controllability of the airplane.

Relevant Service Information

    We've reviewed Boeing Service Bulletin 747-53A2459, Revision 1, 
dated March 11, 2004. Revision 1 of the service bulletin describes 
certain inspection procedures that are similar to those described in 
Boeing Alert Service Bulletin 747-53A2459, dated January 11, 2001, 
which AD 2002-18-04 refers to as the applicable source of service 
information for certain actions required by that AD. Revision 1 of the 
service bulletin, however, expands the inspection area to include 
fastener holes inboard of the body frame.
    Part 5 of Revision 1 of the service bulletin describes procedures 
for post-modification/repair inspections. These inspections use the 
open-hole high-frequency eddy current (HFEC) inspection method. These 
inspections are intended to find cracking of the STA 340 and STA 360 
upper deck floor beams at fastener holes common to the upper chord, 
reinforcement straps, and body frame. The service bulletin also 
describes procedures for surface HFEC inspections for cracking along 
the lower edge of the upper chord and reinforcement straps of the floor 
beams, which you can use as an alternative to the post-modification/
repair open-hole HFEC inspections. (AD 2002-18-04 specifies that you 
must do post-modification/repair inspections in accordance with a 
method that we approve, or in accordance with data meeting the type 
certification basis of the airplane approved by an authorized Boeing 
Company Designated Engineering Representative (DER).) The service 
bulletin specifies repeating the inspection at intervals of 1,000 
flight cycles (if you used the surface HFEC method for the most recent 
inspection), or 3,000 or 6,000 flight cycles,

[[Page 64527]]

depending on fastener location (if you used the open-hole HFEC method 
for the most recent inspection).
    Part 5 of the service bulletin also describes procedures for 
corrective actions if you find cracking during the post-modification/
repair inspections. These corrective actions include repairing cracking 
of the floor beam and body frame, or replacing, with new parts:
     The outboard end of the upper chord (if you find cracking 
of the upper chord).
     The outboard end of the web (if you find cracking of the 
floor beam web).
     The reinforcement strap (if you find cracking of the 
reinforcement strap).
    Part 6 of Revision 1 of the service bulletin describes procedures 
for doing a one-time open-hole HFEC inspection of the fastener holes 
common to the reinforcement straps on airplanes that were modified in 
accordance with the original issue of the service bulletin, and taking 
corrective actions if necessary. The corrective actions in Part 6 are 
the same as those in Part 5, which we describe in the preceding 
paragraph.
    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've evaluated all pertinent information and identified an unsafe 
condition that is likely to exist or develop on other products of this 
same type design. Therefore, we're proposing this AD, which would 
supersede AD 2002-18-04. This proposed AD would continue to require 
one-time inspections for cracking in certain upper deck floor beams, 
and other specified actions. This proposed AD would expand the existing 
inspection area to include fastener holes inboard of the body frame, 
and would require performing a one-time inspection for cracking of 
fastener holes in certain areas of airplanes modified previously, and 
taking corrective actions if necessary. This action also would define 
new sources for instructions for repairs and post-modification/repair 
inspections. This proposed AD would require you to use the service 
information described previously to do these actions, except as 
discussed under ``Differences Between the Proposed AD and Service 
Bulletin.''

Differences Between the Proposed AD and Service Bulletin

    The service bulletin specifies doing the initial post-modification/
repair inspections in accordance with Figures 12 and 13 of the service 
bulletin within 6,000 flight cycles after doing the modification or 
permanent repair. We've added a grace period of 1,000 flight cycles 
after the effective date of this AD for this inspection, to ensure that 
operators of airplanes that have accumulated close to or more than 
6,000 flight cycles since the modification or permanent repair was done 
have sufficient time to perform these proposed inspections.
    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 type certification basis of the 
airplane, and that have been approved by a Boeing Company DER whom 
we've authorized to make such findings.
    Although the Accomplishment Instructions of Boeing Service Bulletin 
747-53A2459, Revision 1, describe procedures for reporting certain body 
frame cracks found on certain airplanes, this proposed AD would not 
require those actions. We don't need this information from operators.
    For airplanes inspected previously in accordance with Boeing Alert 
Service Bulletin 747-53A2459 (but not previously modified or repaired), 
Boeing Service Bulletin 747-53A2459, Revision 1, does not specify a 
compliance time for inspecting the fastener holes inboard of the body 
frame that were added in Revision 1. Paragraph (j) of this proposed AD 
specifies these compliance times for that inspection:

                   Compliance Times for Paragraph (j)
------------------------------------------------------------------------
  Total number of accumulated flight
  cycles as of the effective date of            Compliance time
               this AD
------------------------------------------------------------------------
22,000 or fewer......................  Within 5,000 flight cycles after
                                        the initial open-hole HFEC
                                        inspection for cracking in
                                        accordance with paragraph (f) of
                                        this AD, or within 1,000 flight
                                        cycles after the effective date
                                        of this AD, whichever is later.
22,001 or more.......................  Prior to the accumulation of
                                        25,000 total flight cycles, or
                                        within 1,000 flight cycles after
                                        the effective date of this AD,
                                        whichever is later.
------------------------------------------------------------------------

    In developing an appropriate compliance time for this inspection, 
we considered the manufacturer's recommended compliance times for the 
other inspections in this proposed AD, and the degree of urgency 
associated with the subject unsafe condition. In light of these 
factors, we find that the specified compliance times represent an 
appropriate interval of time for affected airplanes to continue to 
operate without compromising safety.

Changes to Existing AD

    This proposed AD would retain all requirements of AD 2002-18-04. 
Since AD 2002-18-04 was issued, the AD format has been revised, and 
certain paragraphs have been rearranged. As a result, the corresponding 
paragraph identifiers have changed in this proposed AD, as listed in 
the following table:

                      Revised Paragraph Identifiers
------------------------------------------------------------------------
                                             Corresponding  requirement
       Requirement in AD 2002-18-04             in this  proposed AD
------------------------------------------------------------------------
paragraph (a).............................  paragraph (f).
paragraph (b).............................  paragraph (g).
paragraph (c).............................  paragraph (h).
paragraph (d).............................  paragraph (i).
------------------------------------------------------------------------

    Also, AD 2002-18-04 estimated that the number of work hours 
necessary for the post-modification/repair inspection was 8 work hours 
per inspection cycle. We reached that estimate based on the best-
available data at the time. As explained previously, Revision 1 of the 
service bulletin includes procedures for these inspections and 
estimates that they will take about 24 work hours. We've revised the 
``Costs of Compliance'' section of this proposed AD accordingly.

Costs of Compliance

    This proposed AD would affect about 433 airplanes worldwide. The 
following table provides the estimated costs for U.S. operators to 
comply with this proposed AD.

[[Page 64528]]



                                                                     Estimated Costs
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                               Average
            Action                       Work hours          labor rate       Cost per airplane       No. of U.S.-registered          Fleet cost
                                                              per hour                                       airplanes
--------------------------------------------------------------------------------------------------------------------------------------------------------
Initial inspections (required   8..........................         $65  $520.......................  125...................  $65,000
 by AD 2002-18-04).
Modification/permanent repair   24.........................          65  1,560......................  125...................  195,000
 (required by AD 2002-18-04).
Post-mod/repair inspections     24, per inspection cycle...          65  1,560, per inspection cycle  125...................  195,000, per inspection
 (required by AD 2002-18-04).                                                                                                  cycle.
One-time inspection of          24.........................          65  1,560......................  N/A...................  1,560, per airplane.
 fastener holes inboard of the
 body frame (new requirement).
--------------------------------------------------------------------------------------------------------------------------------------------------------

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 removing amendment 39-12878 (67 FR 
57510, September 11, 2002) and adding the following new airworthiness 
directive (AD):

Boeing: Docket No. FAA-2004-19535; Directorate Identifier 2004-NM-
78-AD.

Comments Due Date

    (a) The Federal Aviation Administration must receive comments on 
this airworthiness directive (AD) action by December 20, 2004.

Affected ADs

    (b) This AD supersedes AD 2002-18-04, amendment 39-12878.

Applicability

    (c) This AD applies to Model 747-100, 747-100B, 747-100B SUD, 
747-200B, 747-300, 747SP, and 747SR series airplanes; line numbers 1 
through 810 inclusive; certificated in any category; and not 
equipped with a nose cargo door.

Unsafe Condition

    (d) This AD was prompted by reports of fatigue cracking of the 
upper chord of certain upper deck floor beams. We are issuing this 
AD to find and fix cracking in certain upper deck floor beams, which 
could extend and sever floor beams adjacent to the body frame and 
result in rapid depressurization and loss of controllability 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.

Requirements of AD 2002-18-04

Inspections

    (f) At the compliance time specified in paragraph (f)(1) or 
(f)(2) of this AD, as applicable, perform one-time detailed and 
open-hole high-frequency eddy current (HFEC) inspections for 
cracking in the upper deck floor beams at station (STA) 340 and STA 
360, in accordance with Boeing Alert Service Bulletin 747-53A2459, 
dated January 11, 2001; or Boeing Service Bulletin 747-53A2459, 
Revision 1, dated March 11, 2004. As of the effective date of this 
AD, only Revision 1 may be used. For the purposes of this AD, flight 
cycles with a cabin differential pressure of 2.0 psi or less are not 
calculated into the compliance thresholds specified in this AD. 
However, all cabin pressure records must be maintained for each 
airplane, and no fleet averaging of cabin pressure is allowed.

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

    (1) For airplanes with 22,000 or fewer total flight cycles as of 
October 16, 2002 (the effective date of AD 2002-18-04, amendment 39-
12878): Do the inspections prior to the accumulation of 16,000 total 
flight cycles, or within 1,500 flight cycles after October 16, 2002, 
whichever is later.
    (2) For airplanes with more than 22,000 total flight cycles as 
of the effective date of this AD: Do the inspections within 500 
flight cycles after October 16, 2002.

Modification

    (g) If no crack is found during the inspections in accordance 
with paragraph (f) of this AD: Within 5,000 flight cycles after the 
initial inspections, modify the upper deck floor beams at STA 340 
and STA 360, in accordance with Boeing Alert Service Bulletin 747-
53A2459, dated January 11, 2001; or Boeing Service Bulletin 747-
53A2459, Revision 1, dated March 11, 2004. As of the effective date 
of this AD, only Revision 1 may be used. If this modification is not 
done before further flight after the inspections required by 
paragraph (f) of this AD, those inspections must be repeated one 
time, immediately before accomplishing the modification in this 
paragraph. If any crack is found during these repeat inspections, 
before further flight, accomplish paragraph (h)(2) of this AD.

Repair

    (h) If any crack is found during the inspections in accordance 
with paragraph (f) of this AD: Before further flight, repair in 
accordance with either paragraph (h)(1) or (h)(2) of this AD.
    (1) Accomplish repairs in accordance with paragraphs (h)(1)(i) 
and (h)(1)(ii) of this AD.
    (i) Accomplish a time-limited repair (including removing certain 
fasteners and the existing strap, performing open-hole HFEC 
inspections of the chord and web, stop-drilling web cracks, 
replacing the outboard section of the web, if applicable, and 
installing new straps) in accordance with Boeing Alert Service 
Bulletin 747-53A2459, dated January 11, 2001; or Boeing Service

[[Page 64529]]

Bulletin 747-53A2459, Revision 1, dated March 11, 2004; except where 
the service bulletin specifies to contact Boeing for appropriate 
action, repair in accordance with a method approved by the Manager, 
Seattle Aircraft Certification Office (ACO), FAA; or in accordance 
with data meeting the type certification basis of the airplane 
approved by a Boeing Company Designated Engineering Representative 
(DER) who has been authorized by the Manager, Seattle ACO, to make 
such findings. For a repair method to be approved as required by 
this paragraph, the approval must specifically reference this AD. As 
of the effective date of this AD, only Revision 1 may be used.
    (ii) Within 18 months or 1,500 flight cycles after installation 
of the time-limited repair in accordance with paragraph (h)(1)(i) of 
this AD, whichever is first, do paragraph (h)(2) of this AD.
    (2) Accomplish a permanent repair in accordance with Boeing 
Alert Service Bulletin 747-53A2459, dated January 11, 2001; or 
Boeing Service Bulletin 747-53A2459, Revision 1, dated March 11, 
2004; except where the service bulletin specifies to contact Boeing 
for appropriate action, repair in accordance with a method approved 
by the Manager, Seattle ACO; or in accordance with data meeting the 
type certification basis of the airplane approved by a Boeing 
Company DER who has been authorized by the Manager, Seattle ACO, to 
make such findings. For a repair method to be approved as required 
by this paragraph, the approval must specifically reference this AD. 
As of the effective date of this AD, only Revision 1 may be used.

Repetitive Inspections: Post-Modification/Repair

    (i) Within 15,000 flight cycles after modification of the upper 
deck floor beams in accordance with paragraph (g) of this AD or 
after permanent repair of the upper deck floor beams in accordance 
with paragraph (h) of this AD, as applicable: Perform either open-
hole HFEC inspections for cracking of fastener holes common to the 
upper chord, reinforcement straps, and the body frame; or surface 
HFEC inspections for cracking along the lower edge of the upper 
chord of the floor beam at the intersection with the body frame; and 
repeat these inspections at the interval specified in paragraph 
(i)(1) or (i)(2) of this AD, as applicable, until the initial 
inspection required by paragraph (l) of this AD is complete. Perform 
these inspections and repair any cracking found during these 
inspections in accordance with a method approved by the Manager, 
Seattle ACO, or in accordance with data meeting the type 
certification basis of the airplane approved by a Boeing Company DER 
who has been authorized by the Manager, Seattle ACO, to make such 
findings. For an inspection or repair method to be approved as 
required by this paragraph, the approval must specifically reference 
this AD.
    (1) If the most recent inspection used the surface HFEC method: 
Repeat the inspection within 1,000 flight cycles.
    (2) If the most recent inspection used the open-hole HFEC 
method: Repeat the inspection every 3,000 flight cycles.

    Note 2: There is no terminating action at this time for the 
repetitive post-modification/repair inspections in accordance with 
paragraph (i) of this AD, and instructions for these inspections are 
not provided in the original issue of Boeing Alert Service Bulletin 
747-53A2459, dated January 11, 2001.

New Requirements of This AD

One-Time Inspection for Airplanes Inspected Previously

    (j) For airplanes on which the inspection in paragraph (f) of 
this AD has been done prior to the effective date of this AD in 
accordance with Boeing Alert Service Bulletin 747-53A2459, dated 
January 11, 2001, but the modification specified in paragraph (g) or 
the permanent repair specified in paragraph (h) of this AD has not 
been done: At the applicable time specified in Table 1 of this AD, 
do one-time detailed and open-hole HFEC inspections for cracking of 
the fastener holes inboard of the body frame that were not 
previously inspected on the STA 340 and STA 360 upper deck floor 
beams. Do this inspection in accordance with Part 1 of the 
Accomplishment Instructions of Boeing Service Bulletin 747-53A2459, 
Revision 1, dated March 11, 2004.

              Table 1.--Compliance Times for Paragraph (j)
------------------------------------------------------------------------
  Total number of accumulated flight
  cycles as of the effective date of            Compliance time
               this AD
------------------------------------------------------------------------
22,000 or fewer......................  Within 5,000 flight cycles after
                                        the initial open-hole HFEC
                                        inspection for cracking in
                                        accordance with paragraph (f) of
                                        this AD, or within 1,000 flight
                                        cycles after the effective date
                                        of this AD, whichever is later.
22,001 or more.......................  Prior to the accumulation of
                                        25,000 total flight cycles, or
                                        within 1,000 flight cycles after
                                        the effective date of this AD,
                                        whichever is later.
------------------------------------------------------------------------

One-Time Inspection for Airplanes Modified/Repaired Previously

    (k) For airplanes on which the modification specified in 
paragraph (g) or the permanent repair specified in paragraph (h) of 
this AD has been done prior to the effective date of this AD in 
accordance with Boeing Alert Service Bulletin 747-53A2459, dated 
January 11, 2001: At the applicable time specified in Table 2 of 
this AD, do a one-time open-hole HFEC inspection for cracking of 
fastener holes common to the modification straps, in accordance with 
Part 6 of the Accomplishment Instructions of Boeing Service Bulletin 
747-53A2459, Revision 1, dated March 11, 2004.

              Table 2.--Compliance Times for Paragraph (k)
------------------------------------------------------------------------
  Total number of accumulated flight
   cycles when the modification or              Compliance time
      permanent repair was done
------------------------------------------------------------------------
22,000 or fewer......................  Within 3,000 flight cycles after
                                        doing the modification or
                                        permanent repair, or 1,000
                                        flight cycles after the
                                        effective date of this AD,
                                        whichever is later.
22,001 or more.......................  Within 1,500 flight cycles after
                                        doing the modification or
                                        permanent repair, or 1,000
                                        flight cycles after the
                                        effective date of this AD,
                                        whichever is later.
------------------------------------------------------------------------

Repetitive Inspections: Post-Modification/Repair

    (l) Do open-hole HFEC inspections for cracking of the STA 340 
and STA 360 upper deck floor beams at fastener holes common to the 
upper chord, reinforcement straps, and body frame; or do surface 
HFEC inspections for cracking along the lower edge of the upper 
chord and reinforcement straps of the floor beams. Do the applicable 
inspection in accordance with Part 5 of the Accomplishment 
Instructions of Boeing Service Bulletin 747-53A2459, Revision 1, 
dated March 11, 2004. Do the initial inspections at the applicable 
times specified in Table 3 of this AD, and repeat the inspection at 
the applicable interval specified

[[Page 64530]]

in Figure 9 of the service bulletin. Completing the initial 
inspection required by this paragraph terminates the repetitive 
inspections required by paragraph (i) of this AD. For airplanes on 
which paragraph (i) of this AD has not been done, doing the initial 
inspection required by this paragraph at the specified compliance 
time eliminates the need to comply with paragraph (i) of this AD.

 Table 3.--Compliance Times for Initial Inspection Required by Paragraph
                                   (l)
------------------------------------------------------------------------
     For the inspections
 identified in the following  For these airplanes--
figures referenced in figure                         Do the inspection--
 9 of the service bulletin--
------------------------------------------------------------------------
Figure 10 or 11.............  Airplanes not         Within 15,000 flight
                               inspected             cycles after doing
                               previously in         the modification or
                               accordance with       permanent repair.
                               paragraph (i) of
                               this AD.
Figure 10 or 11.............  Airplanes inspected   Within 1,000 flight
                               previously in         cycles after the
                               accordance with       most recent
                               paragraph (i) of      inspection.
                               this AD using the
                               surface HFEC method
                               for the most recent
                               inspection.
Figure 10 or 11.............  Airplanes inspected   Within 3,000 flight
                               previously in         cycles after the
                               accordance with       most recent
                               paragraph (i) of      inspection.
                               this AD using the
                               open-holeHFEC
                               method for the most
                               recent inspection.
Figure 12 or 13.............  All airplanes.......  Within 6,000 flight
                                                     cycles after doing
                                                     the modification or
                                                     permanent repair,
                                                     or within 1,000
                                                     flight cycles after
                                                     the effective date
                                                     of this AD,
                                                     whichever is later.
------------------------------------------------------------------------

Repair

    (m) If any crack is found during any inspection required by 
paragraph (j), (k), or (l) of this AD: Before further flight, repair 
in accordance with the Accomplishment Instructions of Boeing Service 
Bulletin 747-53A2459, Revision 1, dated March 11, 2004; except where 
the service bulletin specifies to contact Boeing for appropriate 
action, repair in accordance with a method approved by the Manager, 
Seattle ACO; or in accordance with data meeting the type 
certification basis of the airplane approved by a Boeing Company DER 
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.

Reporting Not Required

    (n) Although Boeing Service Bulletin 747-53A2459, Revision 1, 
dated March 11, 2004, specifies to report certain body frame cracks 
on certain airplanes, this AD does not include that requirement.

Alternative Methods of Compliance (AMOCs)

    (o)(1) The Manager, Seattle ACO, 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.
    (3) AMOCs approved previously in accordance with AD 2002-18-04, 
amendment 39-12878, are approved as alternative methods of 
compliance with paragraphs (f), (g), (h), and (i) of this AD.

    Issued in Renton, Washington, on October 26, 2004.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 04-24723 Filed 11-4-04; 8:45 am]
BILLING CODE 4910-13-P