[Federal Register Volume 68, Number 117 (Wednesday, June 18, 2003)]
[Proposed Rules]
[Pages 36506-36509]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 03-15324]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2001-NM-238-AD]
RIN 2120-AA64


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

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the adoption of a new airworthiness 
directive (AD) that is applicable to all Boeing Model 747-100, 747-
100B, 747-100B SUD, 747-200B, 747-200F, 747-200C, 747-300, 747SR, and 
747SP series airplanes. This proposal would require repetitive 
inspections for discrepancies of the structure near and common to the 
upper chord and splice fittings of the rear spar of the wing, and 
repair if necessary. This proposal also would provide for an optional 
modification that, if accomplished, would terminate the repetitive 
inspection requirement, but would necessitate eventual post-
modification inspections. This action is necessary to find and fix 
fatigue cracking of structure near and common to the upper chord and 
splice fittings of the rear spar of the wing, which could result in 
loss of structural integrity of

[[Page 36507]]

the airplane. This action is intended to address the identified unsafe 
condition.

DATES: Comments must be received by August 4, 2003.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2001-NM-238-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056. Comments may be inspected at this 
location between 9 a.m. and 3 p.m., Monday through Friday, except 
Federal holidays. Comments may be submitted via fax to (425) 227-1232. 
Comments may also be sent via the Internet using the following address: 
[email protected]. Comments sent via fax or the Internet must 
contain ``Docket No. 2001-NM-238-AD'' in the subject line and need not 
be submitted in triplicate. Comments sent via the Internet as attached 
electronic files must be formatted in Microsoft Word 97 for Windows or 
ASCII text.
    The service information referenced in the proposed rule may be 
obtained from Boeing Commercial Airplane Group, PO Box 3707, Seattle, 
Washington 98124-2207. This information may be examined at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington.

FOR FURTHER INFORMATION CONTACT: Tamara Anderson, Aerospace Engineer, 
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
917-6421; fax (425) 917-6590.

SUPPLEMENTARY INFORMATION:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed rule by submitting such written data, views, or arguments as 
they may desire. Communications shall identify the Rules Docket number 
and be submitted in triplicate to the address specified above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule. The proposals contained in this action may be changed in 
light of the comments received.
    Submit comments using the following format:
    [sbull] Organize comments issue-by-issue. For example, discuss a 
request to change the compliance time and a request to change the 
service bulletin reference as two separate issues.
    [sbull] For each issue, state what specific change to the proposed 
AD is being requested.
    [sbull] Include justification (e.g., reasons or data) for each 
request.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the proposed rule. All 
comments submitted will be available, both before and after the closing 
date for comments, in the Rules Docket for examination by interested 
persons. A report summarizing each FAA-public contact concerned with 
the substance of this proposal will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this action must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 2001-NM-238-AD.'' The postcard will be date stamped 
and returned to the commenter.

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules 
Docket No. 2001-NM-238-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The FAA has received reports indicating that fatigue cracking has 
been found on the wing on several Boeing Model 747-100 and 747-200B 
series airplanes. The cracking is adjacent and common to the upper 
chord and splice fittings of the rear spar of the wing. Such cracking, 
if not corrected, could result in loss of structural integrity of the 
airplane.
    The subject area on Model 747-100B, 747-100B SUD, 747-200F, 747-
200C, 747-300, 747SR, and 747SP series airplanes is similar to that on 
the affected Model 747-100 and 747-200B series airplanes. Therefore, 
all of these airplanes may be subject to the same unsafe condition.

Explanation of Relevant Service Information

    The FAA has reviewed and approved Boeing Alert Service Bulletin 
747-57A2314, Revision 1, dated January 9, 2003, which describes 
procedures for repetitive inspections for discrepancies of the 
structure near and common to the upper chord and splice fittings of the 
rear spar of the wing, and repair if necessary. The inspection 
procedures include removing existing bolts; performing an ultrasonic or 
magnetic particle inspection for cracking of removed H-11 bolts; 
performing a detailed inspection of all other removed bolts for 
cracking, corrosion, or damage; replacing cracked, corroded, or damaged 
bolts with new improved bolts; removing any installed repair bushings; 
performing an open-hole high frequency eddy current (HFEC) inspection 
for cracking of the bolt holes; installing new bushings if necessary; 
reinstalling bolts that are not cracked, corroded, or damaged; torquing 
the nuts; performing a detailed inspection of the shim between the kick 
fitting and bulkhead strap for cracking or migration; and replacing the 
shim with a new shim if necessary. Accomplishment of the actions 
specified in the service bulletin is intended to adequately address the 
identified unsafe condition.
    The service bulletin also describes procedures for an optional 
modification, which involves removing installed repair bushings, 
performing an open-hole HFEC inspection for cracking of the bolt holes, 
repairing any cracking that is found, oversizing bolt holes, and 
installing new improved bolts. Accomplishment of the optional 
modification eliminates the need for the repetitive inspections 
described previously, but necessitates eventual post-modification 
inspections. The post-modification inspections involve procedures 
similar to those for the pre-modification inspections, which were 
described previously.

Explanation of Requirements of Proposed Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other products of this same type design, the 
proposed AD would require accomplishment of the actions specified in 
the service bulletin described previously, except as discussed below 
under the heading ``Differences Between Proposed Rule and Service 
Bulletin.''

Clarification of Credit for Actions Accomplished Previously

    Flag Note 1 of the logic diagram in Figure 1 of Boeing Alert 
Service Bulletin 747-57A2314, Revision 1, specifies that, for certain 
fastener holes on certain airplanes, an inspection per Figure 4, Step 
14, of Boeing Service Bulletin 747-57-2110 is considered acceptable for 
compliance with the initial inspection specified in paragraph (a) of 
this proposed AD. We have reviewed and approved Boeing Service Bulletin 
747-57-2110, Revision 6, dated November 21, 1991; and Revision 7, dated 
April 23, 1998; and have determined that accomplishment of an initial 
inspection before the effective date of this AD per Figure 4, Step 14, 
of one of those revisions of the service bulletin would provide an 
acceptable level of safety.

[[Page 36508]]

We have also reviewed Boeing Service Bulletin 747-57-2110, Revision 3, 
dated February 19, 1987; Revision 4, dated May 26, 1988; and Revision 
5, dated October 26, 1989. We have determined that accomplishment of an 
initial inspection before the effective date of this AD per Figure 4, 
Step 9, of one of those revisions of the service bulletin would provide 
an acceptable level of safety. The first repeat inspection per 
paragraph (b) of this proposed AD would be required to be accomplished 
at the applicable interval established in paragraph (b) of this 
proposed AD after the most recent inspection per Figure 4, Step 14, of 
Boeing Service Bulletin 747-57-2110, Revision 6 or 7; or Figure 4, Step 
9, of Boeing Service Bulletin 747-57-2110, Revision 3, 4, or 5.

Differences Between Proposed Rule and 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.
    Operators should also note that, although Appendix B of Boeing 
Alert Service Bulletin 747-57A2314, Revision 1, describes procedures 
for reporting discrepancies found during an inspection, this proposed 
AD would not require those actions.

Cost Impact

    There are approximately 593 airplanes of the affected design in the 
worldwide fleet. The FAA estimates that 176 airplanes of U.S. registry 
would be affected by this proposed AD.
    It would take approximately 8 work hours per airplane to accomplish 
the proposed inspection, at an average labor rate of $60 per work hour. 
Based on these figures, the cost impact of the proposed inspection on 
U.S. operators is estimated to be $84,480, or $480 per airplane, per 
inspection cycle.
    The cost impact figure discussed above is based on assumptions that 
no operator has yet accomplished any of the proposed requirements of 
this AD action, and that no operator would accomplish those actions in 
the future if this proposed 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.
    Should an operator elect to accomplish the optional terminating 
action that would be provided by this AD action, it would take 
approximately 22 work hours to accomplish it, at an average labor rate 
of $60 per work hour. The cost of required parts would be approximately 
$10,700 per airplane. Based on these figures, the cost impact of the 
optional terminating action would be approximately $12,020 per 
airplane.
    If the optional terminating action provided by this AD action is 
accomplished, an eventual post-modification inspection would be 
necessary. That inspection would take approximately 8 work hours per 
airplane to accomplish, at an average labor rate of $60 per work hour. 
Based on these figures, the cost impact of the post modification 
inspections would be approximately $480 per airplane, per inspection 
cycle.

Regulatory Impact

    The regulations proposed herein 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. Therefore, it 
is determined that this proposal would not have federalism implications 
under Executive Order 13132.
    For the reasons discussed above, I certify that this 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) if promulgated, 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 copy of the draft 
regulatory evaluation prepared for this action is contained in the 
Rules Docket. A copy of it may be obtained by contacting the Rules 
Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 
part 39 of the Federal Aviation Regulations (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. Section 39.13 is amended by adding the following new 
airworthiness directive:

Boeing: Docket 2001-NM-238-AD.

    Applicability: All Model 747-100, 747-100B, 747-100B SUD, 747-
200B, 747-200F, 747-200C, 747-300, 747SR, and 747SP series 
airplanes; certificated in any category.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
modified, altered, or repaired in the area subject to the 
requirements of this AD. For airplanes that have been modified, 
altered, or repaired so that the performance of the requirements of 
this AD is affected, the owner/operator must request approval for an 
alternative method of compliance in accordance with paragraph (k) of 
this AD. The request should include an assessment of the effect of 
the modification, alteration, or repair on the unsafe condition 
addressed by this AD; and, if the unsafe condition has not been 
eliminated, the request should include specific proposed actions to 
address it.

    Compliance: Required as indicated, unless accomplished 
previously.
    To find and fix fatigue cracking of structure near and common to 
the upper chord and splice fittings of the rear spar of the wing, 
which could result in loss of structural integrity of the airplane, 
accomplish the following:

Initial Inspections

    (a) Perform inspections for discrepancies of the structure near 
and common to the upper chord and splice fittings of the rear spar 
of the wing, per Part 2 of the Accomplishment Instructions of Boeing 
Alert Service Bulletin 747-57A2314, Revision 1, dated January 9, 
2003. The inspection procedures include removing existing bolts; 
performing an ultrasonic or magnetic particle inspection for 
cracking of removed H-11 bolts; performing a detailed inspection of 
all other removed bolts for cracking, corrosion, or damage; 
replacing cracked, corroded, or damaged bolts with new improved 
bolts; removing any installed repair bushings; performing an open-
hole high frequency eddy current (HFEC) inspection for cracking of 
the bolt holes; installing new bushings, if necessary; reinstalling 
bolts that are not cracked, corroded, or damaged; torquing the nuts; 
performing a detailed inspection of the shim between the kick 
fitting and bulkhead strap for cracking or migration; and replacing 
the shim with a new shim if necessary, except as provided by 
paragraph (h) of this AD. Do the initial inspection at the time 
specified in paragraph (a)(1) or (a)(2) of this AD, whichever is 
later.
    (1) Inspect at the earlier of the applicable times specified in 
the ``Flights'' and ``Hours'' columns under the heading ``Initial

[[Page 36509]]

Inspection Threshold'' in Table 1 of Figure 1 of the service 
bulletin. Where the ``Initial Inspection Threshold'' column of Table 
1 of Figure 1 of the service bulletin specifies ``flights'' and 
``hours,'' for the purposes of this paragraph the numbers in that 
column are considered to be the airplane's total flight cycles and 
total flight hours.
    (2) Inspect within 18 months after the effective date 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.''

Repetitive Inspections

    (b) Repeat the inspection required by paragraph (a) of this AD 
at intervals not to exceed the earlier of the times specified in the 
``Flights'' and ``Hours'' columns under the heading ``Repeat 
Inspection Intervals'' in Table 1 of Figure 1 of Boeing Alert 
Service Bulletin 747-57A2314, Revision 1, dated January 9, 2003, 
until paragraph (d) of this AD is accomplished. Where the ``Repeat 
Inspection Intervals'' column of Table 1 of Figure 1 of the service 
bulletin specifies ``flights'' and ``hours,'' for the purposes of 
this paragraph, the figures in that column are considered to be the 
number of flight cycles and flight hours from the time of the most 
recent inspection per paragraph (a) or (b) of this AD, except as 
provided by paragraph (g) of this AD.

Repair

    (c) If any cracking is found during any inspection required by 
paragraph (a) or (b) of this AD, before further flight, repair per 
the Accomplishment Instructions of Boeing Alert Service Bulletin 
747-57A2314, Revision 1, dated January 9, 2003, except as provided 
by paragraph (h) of this AD.

Optional Modification

    (d) Accomplishment of the modification specified in Part 4 of 
the Accomplishment Instructions of Boeing Alert Service Bulletin 
747-57A2314, Revision 1, dated January 9, 2003, constitutes 
terminating action for the initial inspections required by paragraph 
(a) of this AD and the repetitive inspections required by paragraph 
(b) of this AD, provided that the repetitive post-modification 
inspections required by paragraph (e) of this AD are initiated at 
the applicable time. The modification procedures include removing 
installed repair bushings, performing an open-hole HFEC inspection 
for cracking of the bolt holes, repairing any cracking that is 
found, oversizing bolt holes, and installing new improved bolts.

Post-Modification Inspections

    (e) For airplanes on which the optional modification specified 
in paragraph (d) of this AD is accomplished: At the earlier of the 
times specified in the ``Flights'' and ``Hours'' columns under the 
heading ``Post Modification Threshold'' in Table 2 of Figure 1 of 
Boeing Alert Service Bulletin 747-57A2314, Revision 1, dated January 
9, 2003, perform a post-modification inspection per Part 5 of the 
Accomplishment Instructions of Boeing Alert Service Bulletin 747-
57A2314, Revision 1, dated January 9, 2003. The inspection 
procedures include removing existing bolts; performing a detailed 
inspection of removed bolts for cracking, corrosion, or damage; 
replacing cracked, corroded, or damaged bolts with new bolts; 
removing any installed repair bushings; performing an open-hole HFEC 
inspection for cracking of the bolt holes; installing new bushings 
if necessary; reinstalling bolts that are not cracked, corroded, or 
damaged; torquing the nuts; performing a detailed inspection of the 
shim between the kick fitting and bulkhead strap for cracking or 
migration; and replacing the shim with a new shim if necessary; 
except as provided by paragraph (h) of this AD. Where the ``Post 
Modification Inspection Threshold'' column of Table 2 of Figure 1 of 
the service bulletin specifies ``flights'' and ``hours,'' for the 
purposes of this paragraph, the numbers in that column are 
considered to be the flight cycles and flight hours after 
accomplishment of the modification specified in paragraph (d) of 
this AD.
    (1) Repeat the inspection at intervals not to exceed the earlier 
of the times specified in the ``Flights'' and ``Hours'' columns 
under the heading ``Post Modification Repeat Inspection Intervals'' 
in Table 2 of Figure 1 of the service bulletin. Where the ``Post 
Modification Repeat Inspection Intervals'' column of Table 2 of 
Figure 1 of the service bulletin specifies ``flights'' and 
``hours,'' for the purposes of this paragraph, the numbers in that 
column are considered to be the flight cycles and flight hours since 
the most recent inspection per paragraph (e) or (e)(1) of this AD.
    (2) If any cracking is found during any inspection required by 
paragraph (e) or (e)(1) of this AD, before further flight, repair 
per the Accomplishment Instructions of Boeing Alert Service Bulletin 
747-57A2314, Revision 1, dated January 9, 2003, except as provided 
by paragraph (h) of this AD.

Actions Accomplished Per Previous Issue of Service Bulletin

    (f) Inspections, repairs, or modifications accomplished before 
the effective date of this AD per Boeing Alert Service Bulletin 747-
57A2314, including Appendix A and B, dated June 28, 2001, are 
considered acceptable for compliance with the corresponding action 
specified in this AD, except as provided by paragraph (h) of this 
AD.
    (g) As specified in Flag Note 1 of the logic diagram in Figure 1 
of Boeing Alert Service Bulletin 747-57A2314, Revision 1, dated 
January 9, 2003: An inspection accomplished before the effective 
date of this AD per Figure 4, Step 14, of Boeing Service Bulletin 
747-57-2110, Revision 6, dated November 21, 1991; or Revision 7, 
dated April 23, 1998; is considered acceptable, as applicable, for 
compliance with the initial inspection required by paragraph (a) of 
this AD. An inspection accomplished before the effective date of 
this AD per Figure 4, Step 9, of Boeing Service Bulletin 747-57-
2110, Revision 3, dated February 19, 1987; Revision 4, dated May 26, 
1988; and Revision 5, dated October 26, 1989; is also considered 
acceptable, as applicable, for compliance with the initial 
inspection required by paragraph (a) of this AD. The first repeat 
inspection per paragraph (b) of this AD must be accomplished at the 
applicable interval established in paragraph (b) of this AD after 
the most recent inspection per Figure 4, Step 14, of Boeing Service 
Bulletin 747-57-2110, Revision 6 or 7; or Figure 4, Step 9, of 
Boeing Service Bulletin 747-57-2110, Revision 3, 4, or 5.

Exception to Instructions in Service Bulletin

    (h) Where Boeing Alert Service Bulletin 747-57A2314, Revision 1, 
dated January 9, 2003, specifies to contact Boeing for appropriate 
action, before further flight, repair per a method approved by the 
Manager, Seattle ACO, or per 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.
    (i) Although Appendix B of Boeing Alert Service Bulletin 747-
57A2314, Revision 1, dated January 9, 2003, refers to a reporting 
requirement, such reporting is not required by this AD.

Parts Installation

    (j) Except as provided by paragraphs (a) and (b) of this AD, as 
of the effective date of this AD, no person may install any alloy 
steel bolt in any location specified in this AD on any airplane 
listed in the applicability of this AD.

Alternative Methods of Compliance

    (k) An alternative method of compliance or adjustment of the 
compliance time that provides an acceptable level of safety may be 
used if approved by the Manager, Seattle ACO. Operators shall submit 
their requests through an appropriate FAA Principal Maintenance 
Inspector, who may add comments and then send it to the Manager, 
Seattle ACO.

    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Seattle ACO.

Special Flight Permits

    (l) Special flight permits may be issued in accordance with 
sections 21.197 and 21.199 of the Federal Aviation Regulations (14 
CFR 21.197 and 21.199) to operate the airplane to a location where 
the requirements of this AD can be accomplished.

    Issued in Renton, Washington, on June 11, 2003.
Ali Bahrami,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 03-15324 Filed 6-17-03; 8:45 am]
BILLING CODE 4910-13-P