Airworthiness Directives; Boeing Model 747-200F and -200C Series Airplanes, 18277-18282 [05-7000]

Agencies

• Federal Aviation Administration
• DEPARTMENT OF TRANSPORTATION

[Federal Register Volume 70, Number 68 (Monday, April 11, 2005)]
[Rules and Regulations]
[Pages 18277-18282]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 05-7000]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2001-NM-181-AD; Amendment 39-14046; AD 2005-07-21]
RIN 2120-AA64


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

AGENCY: Federal Aviation Administration, Department of Transportation 
(DOT).

ACTION: Final rule.

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SUMMARY: This amendment supersedes an existing airworthiness directive 
(AD), applicable to all Boeing Model 747-200F and -200C series 
airplanes, that currently 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. This amendment requires new one-time inspections 
for cracking of the web, upper chord, and strap of the upper deck floor 
beams. This action also requires modifying or repairing the upper deck 
floor beams, as applicable, which eventually necessitates 
accomplishment of new repetitive inspections for cracking of the upper 
deck floor beams. The actions specified by this AD are intended to 
prevent fatigue cracks in the upper chord and web of upper deck floor 
beams and the resultant failure of such floor beams. Failure of a floor 
beam could result in damage to critical flight control cables and wire 
bundles that pass through the floor beam, and consequent loss of 
controllability of the airplane. Failure of the floor beam also could 
result in the failure of the adjacent fuselage frames and skin, and 
consequent rapid decompression of the airplane. This action is intended 
to address the identified unsafe condition.

DATES: Effective May 16, 2005.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of May 16, 2005.
    The incorporation by reference of Boeing Alert Service Bulletin 
747-53A2420, dated March 26, 1998, as listed in the regulations, was 
approved previously by the Director of the Federal Register as of May 
11, 1998 (63 FR 20311, April 24, 1998).

ADDRESSES: The service information referenced in this AD may be 
obtained from Boeing Commercial Airplanes, P.O. Box 3707, Seattle, 
Washington 98124-2207. This information may be examined at the Federal 
Aviation Administration (FAA), Transport Airplane Directorate, Rules 
Docket, 1601 Lind Avenue, SW., Renton, Washington.

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: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) by superseding AD 98-09-17, 
amendment 39-10498 (63 FR 20311, April 24, 1998); which is applicable 
to all Boeing Model 747-200F and -200C series airplanes; was published 
in the Federal Register on June 18, 2003 (68 FR 36510). The action 
proposed to continue to require 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. The action also proposed to require new one-time 
inspections for cracking of the web, upper chord, and strap of the 
upper deck floor beams. The action also proposed to require 
modification or repair of the upper deck floor beams, as applicable, 
which would eventually necessitate accomplishment of new repetitive 
inspections for cracking of the upper deck floor beams.

Comments

    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. The FAA has duly considered the 
comments received.

Request To Allow Modification/Repair Per Service Bulletin

    One commenter, the airplane manufacturer, requests that we revise 
paragraphs (g) and (h)(2) of the proposed AD to allow modification and 
permanent repairs to be accomplished in accordance with Boeing Alert 
Service Bulletin 747-53A2429, dated March 22, 2001. The same commenter 
also requests that Notes 4 and 5 be removed from the proposed AD. 
(Those notes state that the procedures for the modification and 
permanent repair specified in Boeing Alert Service Bulletin 747-53A2429 
do not provide an adequate level of safety.) The commenter states that 
the procedures in the service bulletin for the modification and 
permanent repair are adequate. The commenter acknowledges, however, 
that analysis has shown that additional inspection locations should be 
added to the post-modification/repair program. The commenter notes that 
the service bulletin will be revised in the future to include 
additional inspection procedures.
    We partially concur with the commenter's request. As we explain in 
the ``Differences Between Proposed AD and Service Bulletins'' section 
of the proposed AD, the procedures for the modification and permanent 
repair stated in the original issue of Boeing Alert Service Bulletin 
747-53A2429 do not provide an adequate level of safety. This 
determination is based on reports that cracking has been found on 
airplanes that have a modification similar to that described in Boeing 
Alert Service Bulletin 747-53A2429. However, we do agree that the 
procedures for the modification and permanent repair specified in 
Boeing Alert Service Bulletin 747-53A2429 would be acceptable if 
additional post-modification/repair inspections are

[[Page 18278]]

performed in accordance with a method that we approve. Accordingly, we 
have made the following changes to this final rule:
     We revised paragraphs (g) and (h) to allow two options for 
compliance.

--Option 1 in each paragraph allows the modification and permanent 
repairs to be accomplished in accordance with a method approved by the 
Manager, Seattle Aircraft Certification Office (ACO), or by an 
Authorized Representative for the Boeing Delegation Option 
Authorization (DOA) organization who has been authorized by the 
Manager, Seattle ACO to make those findings. This option provides an 
opportunity to have approved a modification or repair that is durable 
enough to not need post-modification/repair inspections.
--Option 2 in each paragraph allows the modification and permanent 
repairs to be accomplished in accordance with the service bulletin. If 
this option is chosen, post-modification/repair inspections are 
required.

     We revised paragraph (i) to specify that certain airplanes 
on which a repair in accordance with paragraph (c) of this AD was 
accomplished before the effective date of this AD are subject to 
additional inspection, modification, and/or repair requirements, as 
applicable. (Paragraph (i) of the proposed AD specified that airplanes 
on which the modification or permanent repair specified in Boeing Alert 
Service Bulletin 747-53A2429 was accomplished before the effective date 
of this AD would also be subject to these additional inspection, 
modification, and/or repair requirements. These airplanes are now 
subject to paragraph (k) of this AD instead.)
     We revised paragraph (j) to clarify that the post-
modification/repair inspections in that paragraph apply to airplanes 
modified/repaired in accordance with a method approved or by an 
Authorized Representative for the Boeing DOA organization.
     We added paragraph (k) to require post-modification/repair 
inspections in accordance with a method that we approve for airplanes 
on which the modification or permanent repair is accomplished in 
accordance with the service bulletin.
     We removed Notes 4 and 5 of the proposed AD from this 
final rule.
    We have coordinated this issue with Boeing and it concurs in this 
approach. We have further confirmed that Boeing intends to add 
acceptable instructions for the post-modification/repair inspections in 
a future revision of the service bulletin. Once Boeing has issued, and 
we have reviewed and approved, a revision to the service bulletin, we 
may consider approving that service bulletin as an alternative method 
of compliance (AMOC) with the corresponding requirements of this AD.

Request To Allow Repairs Per Paragraph (h)

    The same commenter requests that we revise paragraph (c) of the 
proposed AD to allow repairs of any cracking found during inspections 
in accordance with paragraph (a) or (b) of the proposed AD to be 
accomplished in accordance with paragraph (h) of the proposed AD. The 
commenter states that this should be acceptable because paragraph (h) 
of the proposed AD defines FAA-approved time-limited and permanent 
repairs.
    We concur. Time-limited repairs in accordance with paragraph (h)(1) 
of this AD, or permanent repairs in accordance with paragraph (h)(2) or 
(h)(3) of this AD, are acceptable for repairing cracks found during the 
inspections required by paragraph (a) or (b) of this AD. We have 
revised paragraph (c) to refer to paragraph (h) of this AD. Also, we 
have revised paragraph (h) of this AD to state that accomplishment of 
paragraph (h)(1), (h)(2), or (h)(3) of this AD is acceptable for any 
crack found during any inspection required by paragraph (a), (b), or 
(e) of this AD.

Request To Omit Inspections for Certain Airplanes Modified/Repaired 
Previously

    The same commenter requests that we revise paragraph (i) of the 
proposed AD to state that certain airplanes that have been modified or 
repaired previously do not require action within 5,000 flight cycles 
after accomplishment of the modification or repair. The commenter 
states that some upper deck floor beam repairs designed by Boeing prior 
to the release of Boeing Service Bulletin 747-53A2429 were consistent 
with the specifications of the modification/permanent repair in that 
service bulletin. The commenter states that these repairs may not need 
action within 5,000 flight cycles except for post-modification/repair 
inspections. A second commenter similarly requests that we reconsider 
the requirement to inspect (and accomplish any necessary corrective 
action) within 5,000 flight cycles after accomplishment of the 
modification or permanent repair. The second commenter justifies its 
request by noting that the modification is intended to improve the 
fatigue resistance of the modified floor beam.
    We partially concur with the commenters' request. As explained 
previously, we have revised paragraph (i) in this final rule to remove 
airplanes on which a modification/permanent repair in accordance with 
Boeing Service Bulletin 747-53A2429 was accomplished before the 
effective date of this AD. These airplanes are now subject to 
repetitive inspections in accordance with paragraph (k) of this AD. 
However, paragraph (i) of this AD still applies to airplanes repaired 
previously in accordance with paragraph (c), if that repair does not 
comply with paragraph (h) of this AD. The additional post-repair 
inspections in paragraph (i) are necessary to ensure that the repair 
provides an adequate level of safety. Operators may request approval of 
an AMOC or adjustment of the compliance times for this AD as specified 
in paragraph (m)(1) of this AD. Also, as explained previously, when the 
future revision to Boeing Alert Service Bulletin 747-53A2429 is 
available, and we have reviewed and approved it, we may consider 
requests for approval of the actions in that revision as an AMOC for 
this AD. We have made no further changes to the final rule in this 
regard.
    A third commenter notes that it has accomplished certain repairs of 
cracking found during inspections in accordance with paragraphs (a) and 
(b) of AD 98-09-17, as restated in paragraphs (a) and (b) of the 
proposed AD. All of these repairs were approved by a Boeing Company DER 
and some included ``terminating action'' similar to that found in 
Boeing Alert Service Bulletin 747-53A2429. The commenter states that 
these repairs should be included under paragraph (i) of the proposed AD 
as repairs and modifications that allow inspections in accordance with 
paragraph (e) of the proposed AD to be deferred for 5,000 flight cycles 
after installation.
    We agree that certain repairs and modifications accomplished 
previously may warrant a 5,000-flight-cycle compliance time before it 
is necessary to accomplish the new inspections. However, these repairs 
and modifications must have been approved under paragraph (c) of the 
existing AD to ensure that they are adequate to address the unsafe 
condition. If these repairs have been approved, then they are covered 
by the provision in paragraph (i) of this AD that provides for a 5,000-
flight-cycle compliance time for airplanes on which a repair in 
accordance with paragraph (c) of this AD was previously accomplished. 
No change to the final rule is necessary in this regard.

[[Page 18279]]

Request To Provide Acceptable Inspection Methods

    One commenter notes that paragraph (i) of the proposed AD would 
require accomplishing inspections of airplanes modified or permanently 
repaired before the effective date of the AD, in accordance with 
paragraph (e) of the proposed AD. The commenter states that paragraph 
(e) does not specify an inspection procedure for floor beams that have 
been modified or permanently repaired.
    We infer that the commenter is requesting that we revise paragraph 
(i) of this AD to specify a method for inspecting floor beams that have 
been previously modified or permanently repaired. We do not concur. The 
inspection methods specified in Figures 1 and 2 of the referenced 
service bulletin are still adequate for modified or repaired floor 
beams, provided that paragraph (g) or (h) of this AD, as applicable, is 
also accomplished, as required by paragraph (i) of this AD. No change 
to the final rule is necessary in this regard.

Request To Revise Post-Modification/Repair Requirements

    One commenter, the airplane manufacturer, requests that we revise 
paragraph (j) of the proposed AD to refer to post-modification/repair 
inspections in accordance with Boeing Alert Service Bulletin 747-
53A2429, as supplemented by procedures in an attachment submitted by 
the commenter. The commenter states that this would eliminate the need 
for paragraphs (j)(1) and (j)(2) of the proposed AD. The commenter also 
requests that we revise paragraph (k) of the proposed AD to require 
repair of any cracking found during post-modification/repair 
inspections to be accomplished in accordance with the procedures 
specified in the attachment submitted by the commenter.
    We partially agree. The original issue of Boeing Alert Service 
Bulletin 747-53A2429 does not provide detailed instructions for post-
modification/repair inspections, nor does it provide acceptable 
procedures for repairing any cracking found during such inspections. We 
are reviewing, with the commenter, the supplemental procedures to which 
the commenter refers. We and the manufacturer agree that the details of 
its proposal are too complex to include in this AD and operators would 
be better served by issuing separate service information containing the 
proposed supplemental procedures. It is likely that the supplemental 
procedures may be included in a future revision of the service 
bulletin. Once a revision to this service bulletin has been issued by 
the manufacturer, and we have reviewed and approved it, we may consider 
approving the use of post-modification/repair inspections specified in 
that revision as an acceptable AMOC for paragraph (j) of this AD. No 
change to the final rule is necessary in this regard.

Request To Revise Applicability

    One commenter requests that we revise the applicability of the 
proposed AD to make the AD applicable only to airplanes with a nose 
cargo door. The commenter states that it converts Boeing Model 747-200 
series airplanes to a Special Freighter configuration that has only a 
main deck side cargo door, in accordance with a supplemental type 
certificate. The commenter questions whether the proposed AD would 
apply to its converted airplanes.
    We acknowledge the commenter's concern but find that no change to 
the proposed AD is necessary to meet the intent of the commenter's 
request. The applicability statement of this AD specifies only Model 
747-200F and -200C series airplanes. This applicability does not 
include Boeing Model 747-200 series airplanes that were delivered as 
passenger airplanes and later converted to the Special Freighter 
configuration. Airplanes that are converted to a freighter 
configuration will still be listed as passenger airplanes on the 
original Type Certificate Data Sheet. Thus, these airplanes are not 
subject to this AD. No change to the final rule is necessary in this 
regard.

Explanation of Additional Changes

    For clarification, we have revised paragraph (j)(1) of this final 
rule to add the words ``for cracking.'' We find that this change does 
not expand the scope of the proposed AD but makes the wording of 
paragraph (j)(1) consistent with that of paragraph (j)(2) of this final 
rule.
    Since the issuance of the proposed AD, Boeing has received a DOA. 
We have revised this final rule to delegate the authority to approve an 
alternative method of compliance for any repair required by this AD to 
the Authorized Representative for the Boeing DOA Organization rather 
than the Designated Engineering Representative (DER).

Conclusion

    After careful review of the available data, including the comments 
noted above, we have determined that air safety and the public interest 
require the adoption of the rule with the changes previously described. 
We have determined that these changes will neither increase the 
economic burden on any operator nor increase the scope of the AD.

Changes to 14 CFR Part 39/Effect on the AD

    On July 10, 2002, the FAA issued a new version of 14 CFR part 39 
(67 FR 47997, July 22, 2002), which governs the FAA's airworthiness 
directives system. The regulation now includes material that relates to 
altered products, special flight permits, and AMOCs. Because we have 
now included this material in part 39, only the office authorized to 
approve AMOCs is identified in each individual AD. Therefore, Note 1 
and paragraph (m) of the proposed AD are not included in this final 
rule (other paragraphs and notes have been re-identified accordingly), 
and paragraph (l) of the proposed AD has been revised (and re-
identified as paragraph (m)) in this final rule.

Explanation of Change to Cost Impact

    We have reviewed the figures we have used over the past several 
years to calculate AD costs to operators. To account for various 
inflationary costs in the airline industry, we find it necessary to 
increase the labor rate used in these calculations from $60 per work 
hour to $65 per work hour. The cost impact information, below, has been 
revised to reflect this increase in the specified hourly labor rate.

Cost Impact

    There are approximately 81 airplanes of the affected design in the 
worldwide fleet. We estimate that 23 airplanes of U.S. registry will be 
affected by this AD.
    For airplanes on which the repetitive detailed inspection that is 
currently required by AD 98-09-17 is accomplished, that inspection 
takes approximately 1 work hour per airplane, at an average labor rate 
of $65 per work hour. Based on these figures, the cost impact of the 
currently required detailed inspection is estimated to be $65 per 
airplane, per inspection cycle.
    The high frequency eddy current (HFEC) inspection that is currently 
required by AD 98-09-17 takes approximately 6 work hours per airplane 
to accomplish, at an average labor rate of $65 per work hour. Based on 
these figures, the cost impact of this currently required inspection on 
U.S. operators is estimated to be $8,970, or $390 per airplane.
    The new one-time detailed and HFEC inspections that are required by 
this AD will take approximately 7 work hours per airplane to 
accomplish, at an average labor rate of $65 per work hour.

[[Page 18280]]

Based on these figures, the cost impact of these new inspections on 
U.S. operators is estimated to be $10,465, or $455 per airplane.
    For airplanes subject to the modification that is required by this 
AD, it will take approximately 172 work hours per airplane to 
accomplish, at an average labor rate of $65 per work hour. Required 
parts will cost approximately $4,959 per airplane. Based on these 
figures, the cost impact of this modification is estimated to be 
$16,139 per airplane.
    For airplanes subject to the repair that is required by this AD, it 
will take approximately 172 work hours per airplane to accomplish, at 
an average labor rate of $65 per work hour. Required parts will cost 
approximately $21,646 to $21,857 per airplane. Based on these figures, 
the cost impact of this repair is estimated to be $32,826 to $33,037 
per airplane.
    The follow-on repetitive inspections that are required by this AD 
will take approximately 6 work hours per airplane to accomplish, at an 
average labor rate of $65 per work hour. Based on these figures, the 
cost impact of these new inspections on U.S. operators is estimated to 
be $8,970, or $390 per airplane, per inspection cycle.
    The cost impact figures discussed above are based on assumptions 
that no operator has yet accomplished any of the requirements of this 
AD action, and that no operator would accomplish those actions in the 
future if this AD were not adopted. The cost impact figures discussed 
in AD rulemaking actions represent only the time necessary to perform 
the specific actions actually required by the AD. These figures 
typically do not include incidental costs, such as the time required to 
gain access and close up, planning time, or time necessitated by other 
administrative actions.

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 Impact

    The regulations adopted herein will 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. Therefore, it 
is determined that this final rule does not have federalism 
implications under Executive Order 13132.
    For the reasons discussed above, I certify that this action (1) is 
not a ``significant regulatory action'' under Executive Order 12866; 
(2) is not a ``significant rule'' under 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. A final evaluation has been prepared for this action 
and it is contained in the Rules Docket. A copy of it may be obtained 
from the Rules Docket at the location provided under the caption 
ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

0
Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends part 39 of 
the Federal Aviation Regulations (14 CFR part 39) as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
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]

0
2. Section 39.13 is amended by removing amendment 39-10498 (63 FR 
20311, April 24, 1998), and by adding a new airworthiness directive 
(AD), amendment 39-14046, to read as follows:

2005-07-21 Boeing: Amendment 39-14046. Docket 2001-NM-181-AD. 
Supersedes AD 98-09-17, Amendment 39-10498.

    Applicability: All Model 747-200F and -200C series airplanes, 
certificated in any category.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent fatigue cracks in the upper chord and web of upper 
deck floor beams and the resultant failure of such floor beams; 
which could result in damage to critical flight control cables and 
wire bundles that pass through the floor beam, and consequent loss 
of controllability of the airplane; or which could result in failure 
of the adjacent fuselage frames and skin, and consequent rapid 
decompression of the airplane; accomplish the following:

Requirements of AD 98-09-17

    Note 1: For the purposes of calculating the compliance threshold 
and repetitive interval for the actions required by paragraphs (a) 
and (b) of this AD, ``flight cycles'' are considered to be flight 
cycles with a cabin pressure differential greater than 2.0 pounds 
per square inch (psi).

Repetitive Inspections of Certain Upper Deck Floor Beams

    (a) For airplanes that have accumulated less than 18,000 total 
flight cycles as of May 11, 1998 (the effective date of AD 98-09-17, 
amendment 39-10498): Prior to the accumulation of 15,000 total 
flight cycles, or within 250 flight cycles after May 11, 1998, 
whichever occurs later, inspect the upper chord, web, and strap of 
the upper deck floor beams at body station (BS) 340 through BS 440 
inclusive, and the upper deck floor beams at BS 500 and BS 520, on 
the right and left sides of the airplane, in accordance with 
paragraph (a)(1) or (a)(2) of this AD. The inspections shall be 
accomplished in accordance with Boeing Alert Service Bulletin 747-
53A2420, dated March 26, 1998; or Boeing Service Bulletin 747-
53A2420, Revision 1, dated January 7, 1999.
    (1) Perform a detailed inspection to detect cracks in accordance 
with Figure 2 of the service bulletin.
    (i) Repeat the detailed inspection thereafter at intervals not 
to exceed 25 flight cycles, until the requirements of paragraph 
(a)(1)(ii) or (e) of this AD are accomplished.
    (ii) Within 500 flight cycles after accomplishment of the 
initial detailed inspection, accomplish paragraph (a)(2) of this AD.
    (2) Perform a one-time open hole high frequency eddy current 
(HFEC) inspection to detect cracks in accordance with Figure 3 of 
the service bulletin. Accomplishment of this action constitutes 
terminating action for the repetitive inspection requirements of 
paragraph (a)(1)(i) of this AD.
    (b) For airplanes that have accumulated 18,000 or more total 
flight cycles as of May 11, 1998: Within 25 flight cycles after May 
11, 1998, inspect the upper chord, web, and strap of the upper deck 
floor beams at BS 340 through BS 440 inclusive, and the upper deck 
floor beams at BS 500 and BS 520, on the right and left sides of the 
airplane, in accordance with paragraph (b)(1) or (b)(2) of this AD. 
The inspections shall be accomplished in accordance with Boeing 
Alert Service Bulletin 747-53A2420, dated March 26, 1998; or Boeing 
Service Bulletin 747-53A2420, Revision 1, dated January 7, 1999.
    (1) Perform a detailed inspection to detect cracks in accordance 
with Figure 2 of the service bulletin.

[[Page 18281]]

    (i) Repeat the detailed inspection thereafter at intervals not 
to exceed 25 flight cycles, until the requirements of paragraph 
(b)(1)(ii) or (e) of this AD are accomplished.
    (ii) Within 250 flight cycles after accomplishment of the 
initial detailed inspection, accomplish paragraph (b)(2) of this AD.
    (2) Perform a one-time open hole HFEC inspection to detect 
cracks in accordance with Figure 3 of the service bulletin. 
Accomplishment of this action constitutes terminating action for the 
repetitive inspection requirements of paragraph (b)(1)(i) of this 
AD.

Repair

    (c) If any cracking is found during any inspection required by 
paragraphs (a) or (b) of this AD, prior to further flight, repair in 
accordance with a method approved by the Manager, Seattle Aircraft 
Certification Office (ACO), FAA; or do paragraph (h) of this AD.

New Requirements of This AD

    Note 2: For the purposes of this AD, a detailed inspection is 
defined as: ``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.''

Adjustments to Compliance Time: Cabin Differential Pressure

    (d) For the purposes of calculating the compliance threshold and 
repetitive interval for the actions required by paragraphs (e), (h), 
(i), (j) and (k) of this AD: The number of flight cycles in which 
cabin differential pressure is at 2.0 psi or less need not be 
counted when determining the number of flight cycles that have 
occurred on the airplane, provided that flight cycles with momentary 
spikes in cabin differential pressure above 2.0 psi are included as 
full pressure cycles. For this provision to apply, all cabin 
pressure records must be maintained for each airplane: No fleet-
averaging of cabin pressure is allowed.

Detailed and Eddy Current Inspections of Certain Upper Deck Floor 
Beams

    (e) Within 5,000 flight cycles after accomplishing the most 
recent inspection required by paragraph (a) or (b) of this AD, or 
within 1,000 flight cycles after the effective date of this AD, 
whichever is later: Do paragraphs (e)(1) and (e)(2) of this AD, in 
accordance with the Accomplishment Instructions of Boeing Alert 
Service Bulletin 747-53A2429, dated March 22, 2001. Accomplishment 
of both paragraphs (e)(1) and (e)(2) of this AD constitutes 
terminating action for the repetitive inspection requirement of 
paragraph (a)(1)(i) or (b)(1)(i) of this AD, as applicable.
    (1) Do a one-time detailed inspection for cracking of the web, 
upper chord, and strap of the upper deck floor beams at BS 340 
through BS 440 inclusive, BS 500, and BS 520, on the right and left 
sides of the airplane, as specified in Figure 1 of the service 
bulletin.
    (2) Do an open-hole HFEC inspection for cracking of the fastener 
holes of the web and upper chord of the upper deck floor beams at BS 
340 through BS 440 inclusive, BS 500, and BS 520, on the right and 
left sides of the airplane, as specified in Figure 2 of the service 
bulletin.

Compliance With Paragraphs (a) or (b) and (e)

    (f) Airplanes on which the inspections required by paragraph (e) 
of this AD are accomplished within the compliance time specified in 
paragraph (a) or (b) of this AD, as applicable, are not required to 
be inspected in accordance with paragraph (a) or (b) of this AD, as 
applicable.

Modification of Upper Deck Floor Beams

    (g) If no cracking is found during the inspections required by 
paragraph (e) of this AD, before further flight after the 
inspection, except as provided by paragraph (i) of this AD, modify 
the upper chord of the upper deck floor beams at the locations in 
Figure 3 of Boeing Alert Service Bulletin 747-53A2429, dated March 
22, 2001, in accordance with paragraph (g)(1) or (g)(2) of this AD.
    (1) Option 1: Accomplish the modification in accordance with a 
method approved by the Manager, Seattle ACO, or by an Authorized 
Representative for the Boeing Delegation Option Authorization (DOA) 
organization, who has been authorized by the Manager, Seattle ACO, 
to make those findings. For a modification method to be approved, 
the modification must meet the certification basis of the airplane, 
and the approval must specifically refer to this AD. After the 
modification, perform post-modification inspections in accordance 
with paragraph (j) of this AD.
    (2) Option 2: Accomplish the modification in accordance with the 
Figure 3 of Boeing Alert Service Bulletin 747-53A2429, dated March 
22, 2001, except, where the service bulletin specifies to contact 
Boeing for appropriate action, modify in accordance with a method 
approved by the Manager, Seattle ACO, or by an Authorized 
Representative for the Boeing DOA organization, who has been 
authorized by the Manager, Seattle ACO, to make those findings. For 
a modification method to be approved, the modification must meet the 
certification basis of the airplane, and the approval must 
specifically refer to this AD. Then, perform post-modification 
inspections in accordance with paragraph (k) of this AD.

Repair of Upper Deck Floor Beams

    (h) If any crack is found during any inspection required by 
paragraph (a), (b), or (e) of this AD: Before further flight, except 
as provided by paragraph (i) of this AD, do paragraph (h)(1), 
(h)(2), or (h)(3) of this AD.
    (1) Option 1: Accomplish all actions associated with the time-
limited repair, including removing the existing strap; performing 
HFEC inspections of the chord, web, and angle, as applicable; stop-
drilling cracks; trimming the angle and machining the vertical leg 
of the chord, as applicable; and installing a new strap. Do these 
actions in accordance with the Accomplishment Instructions of Boeing 
Service Bulletin 747-53A2420, Revision 1, dated January 7, 1999; 
except, where the service bulletin specifies to contact Boeing for 
appropriate action, before further flight, repair in accordance with 
a method approved by the Manager, Seattle ACO, or by an Authorized 
Representative for the Boeing DOA 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. Within 1,500 flight cycles or 18 
months after the installation of the time-limited repair, whichever 
is first, do paragraph (h)(2) or (h)(3) of this AD.
    (2) Option 2: Accomplish the permanent repair of the upper deck 
floor beams at the locations shown in Figures 4 and 5, as 
applicable, of Boeing Alert Service Bulletin 747-53A2429, dated 
March 22, 2001, in accordance with a method approved by the Manager, 
Seattle ACO, or by an Authorized Representative for the Boeing DOA 
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. Then, perform post-
repair inspections in accordance with paragraph (j) of this AD.
    (3) Option 3: Accomplish the permanent repair of the upper deck 
floor beams at locations shown in Figure 4 and 5, as applicable, of 
Boeing Alert Service Bulletin 747-53A2429, dated March 22, 2001, in 
accordance with the service bulletin. Then, perform post-repair 
inspections in accordance with paragraph (k) of this AD.

Airplanes Modified or Repaired Previously

    (i) For airplanes on which a repair in accordance with paragraph 
(c) of this AD was accomplished before the effective date of this 
AD, except a repair that is acceptable for compliance with paragraph 
(h) of this AD: Within 5,000 flight cycles after installation of 
such modification or repair, as applicable, inspect in accordance 
with paragraph (e) of this AD, then do paragraph (g) or (h) of this 
AD, as applicable.

Repetitive Inspections After Modification or Permanent Repair

    (j) For airplanes on which the modification or permanent repair 
was installed in accordance with paragraph (g)(1) or (h)(2) of this 
AD, as applicable: Within 15,000 flight cycles after installation of 
the modification or permanent repair, do paragraph (j)(1) or (j)(2) 
of this AD, in accordance with a method approved by the Manager, 
Seattle ACO. For an inspection method to be approved, the approval 
letter must specifically reference this AD.
    (1) Option 1: Do surface HFEC inspections for cracking along the 
lower edge of the upper chord of the upper deck floor beams at BS 
340 through BS 440 inclusive, BS 500, and BS 520, on the right and 
left sides of the airplane. Repeat the surface HFEC inspections at 
intervals not to exceed 1,000 flight cycles.

[[Page 18282]]

    (2) Option 2: Do open-hole HFEC inspections for cracking at 
fasteners common to the upper chord, reinforcement straps, and body 
frame of the upper deck floor beams at BS 340 through BS 440 
inclusive, BS 500, and BS 520, on the right and left sides of the 
airplane. Repeat the open-hole HFEC inspections at intervals not to 
exceed 3,000 flight cycles.
    (k) For airplanes on which the modification or permanent repair 
was installed in accordance with paragraph (g)(2) or (h)(3) of this 
AD, as applicable: Within 5,000 flight cycles after installation of 
the modification or permanent repair, do repetitive post-
modification/repair inspections of the upper deck floor beams at BS 
340 through BS 440 inclusive, BS 500, and BS 520, on the right and 
left sides of the airplane, in accordance with a method approved by 
the Manager, Seattle ACO. For an inspection method to be approved, 
the approval letter must specifically reference this AD.

Repair

    (l) If any cracking is found during any inspection required by 
paragraph (j) or (k) of this AD: Before further flight, repair in 
accordance with a method approved by the Manager, Seattle ACO, or by 
an Authorized Representative for the Boeing DOA 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.

Alternative Methods of Compliance

    (m)(1) In accordance with 14 CFR 39.19, the Manager, Seattle 
ACO, FAA, is authorized to approve alternative methods of compliance 
(AMOCs) for this AD.
    (2) AMOCs approved previously in accordance with AD 98-09-17, 
amendment 39-10498, are approved as alternative methods of 
compliance with paragraphs (a), (b), and (c) of this AD.

Incorporation by Reference

    (n) Unless otherwise specified in this AD, the actions shall be 
done in accordance with Boeing Alert Service Bulletin 747-53A2420, 
dated March 26, 1998; Boeing Service Bulletin 747-53A2420, Revision 
1, dated January 7, 1999; and Boeing Alert Service Bulletin 747-
53A2429, dated March 22, 2001; as applicable.
    (1) The incorporation by reference of Boeing Service Bulletin 
747-53A2420, Revision 1, dated January 7, 1999; and Boeing Alert 
Service Bulletin 747-53A2429, dated March 22, 2001; is approved by 
the Director of the Federal Register, in accordance with 5 U.S.C. 
552(a) and 1 CFR part 51.
    (2) The incorporation by reference of Boeing Alert Service 
Bulletin 747-53A2420, dated March 26, 1998, was approved previously 
by the Director of the Federal Register as of May 11, 1998 (63 FR 
20311, April 24, 1998).
    (3) Copies may be obtained from Boeing Commercial Airplanes, 
P.O. Box 3707, Seattle, Washington 98124-2207. Copies may be 
inspected at the FAA, Transport Airplane Directorate, 1601 Lind 
Avenue, SW., Renton, Washington; or at the National Archives and 
Records Administration (NARA). For information on the availability 
of this material at NARA, call (202) 741-6030, or go to: https://
www.archives.gov/federal_register/code_of_federal_regulations/
ibr_locations.html.

Effective Date

    (o) This amendment becomes effective on May 16, 2005.

    Issued in Renton, Washington, on April 4, 2005.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 05-7000 Filed 4-8-05; 8:45 am]
BILLING CODE 4910-13-P