[Federal Register Volume 75, Number 130 (Thursday, July 8, 2010)]
[Proposed Rules]
[Pages 39189-39192]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2010-16551]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2010-0674; Directorate Identifier 2010-NM-012-AD]
RIN 2120-AA64
Airworthiness Directives; The Boeing Company Model 747 Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: We propose to adopt a new airworthiness directive (AD) for all
Model 747 airplanes. This proposed AD would require repetitive
inspections for cracking in the body skin around the aft corners of the
nose wheel well; for certain airplanes, repetitive inspections for
cracking in the skin splice plate at the aft corners of the nose wheel
well; and related investigative and corrective actions if necessary.
This proposed AD would also require repetitive post-modification
inspections for cracking in the body skin and the skin splice plate;
for certain airplanes, an inspection for steel cross-shaped doublers on
the larger aluminum doublers; and corrective action if necessary. This
proposed AD would also require repetitive surface high frequency eddy
current (HFEC) inspections of a certain bulkhead outer chord, skin
splice plate, and outer chord radius filler for cracking; repetitive
detailed inspections for cracking of the bulkhead frame web and body
skin; and corrective actions if necessary. This proposed AD would
provide for optional terminating action for certain repetitive
inspections. This proposed AD results from reports of cracking of the
fuselage skin and adjacent internal skin splice plate at the left and
right nose wheel well aft corners, and the outer chord of the body
station (BS) 400 bulkhead. We are proposing this AD to detect and
correct cracking of the fuselage skin or splice plate, which, together
with cracking of the bulkhead outer chord, could result in large skin
cracks and subsequent in-flight rapid decompression of the airplane.
DATES: We must receive comments on this proposed AD by August 23, 2010.
ADDRESSES: You may send comments by any of the following methods:
Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
Fax: 202-493-2251.
Mail: U.S. Department of Transportation, Docket
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New
Jersey Avenue, SE., Washington, DC 20590.
Hand Delivery: U.S. Department of Transportation, Docket
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New
Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m.,
Monday through Friday, except Federal holidays.
For service information identified in this proposed AD, contact
Boeing Commercial Airplanes, Attention: Data & Services Management,
P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; telephone 206-
544-5000, extension 1; fax 206-766-5680; e-mail [email protected];
Internet https://www.myboeingfleet.com. You may review copies of the
referenced service information at the FAA, Transport Airplane
Directorate, 1601 Lind Avenue, SW., Renton, Washington. For information
on the availability of this material at the FAA, call 425-227-1221.
Examining the AD Docket
You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Management Facility
between 9 a.m. and 5 p.m., Monday through Friday, except Federal
holidays. The AD docket contains this proposed AD, the regulatory
evaluation, any comments received, and other information. The street
address for the Docket Office (telephone 800-647-5527) is in the
ADDRESSES section. Comments will be available in the AD docket shortly
after receipt.
FOR FURTHER INFORMATION CONTACT: Ivan Li, Aerospace Engineer, Airframe
Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind
Avenue, SW., Renton, Washington 98057-3356; telephone (425) 917-6437;
fax (425) 917-6590.
SUPPLEMENTARY INFORMATION:
Comments Invited
We invite you to send any written relevant data, views, or
arguments about this proposed AD. Send your comments to an address
listed under the ADDRESSES section. Include ``Docket No. FAA-2010-0674;
Directorate Identifier 2010-NM-012-AD'' at the beginning of your
comments. We specifically invite comments on the overall regulatory,
economic, environmental, and energy aspects of this proposed AD. We
will consider all comments received by the closing date and may amend
this proposed AD because of those comments.
We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We
will also post a report summarizing each substantive verbal contact we
receive about this proposed AD.
Discussion
We have received reports of cracking of the fuselage skin and
adjacent internal skin splice plate at the left and right nose wheel
well aft corners, and the outer chord of the body station (BS) 400
bulkhead. Cracks were found in the skin on an airplane that had
accumulated about 6,355 total flight cycles. In addition, small cracks
were found in the outer chord of the body station (BS) 400 bulkhead on
airplanes that had accumulated fewer than 20,000 total flight cycles.
Cracking of the fuselage skin or splice plate, together with cracking
of the bulkhead outer chord, if not detected and corrected, could
result in large skin cracks and subsequent in-flight rapid
decompression of the airplane.
Relevant Service Information
We have reviewed Boeing Alert Service Bulletin 747-53A2305,
Revision 2, dated January 15, 2009. The service bulletin describes
procedures for repetitive external detailed inspections for cracking in
the body skin around the aft corners of the nose wheel well; for
certain airplanes, repetitive external detailed inspections for
cracking in the skin splice plate at the aft corners of the nose wheel
well, and modification of any cracked aft corners of the nose wheel
well by installing modification doublers; and, for certain airplanes,
and a one-time external general visual inspection for steel cross-
shaped doublers. The modification, which, if accomplished to repair
cracks or to eliminate the need for certain repetitive inspections,
includes related investigative actions and corrective actions if
necessary. The related investigative actions include an open-hole HFEC
inspection for cracking at fasteners common to the bulkhead outer
chord, and a surface HFEC inspection or penetrant inspection for
cracking of the skin if necessary. The corrective actions include
repairing the crack, installing cross-shaped doublers, and contacting
Boeing for repair instructions and doing the repair.
[[Page 39190]]
The service bulletin also describes procedures for repetitive post-
modification inspections, which consist of an external low frequency
eddy current (LFEC) inspection for cracking in the skin around
fasteners at the periphery of modification doublers, and contacting
Boeing for instructions to repair cracks and doing the repair. The
service bulletin also describes procedures for repetitive surface HFEC
inspections for cracking of a certain bulkhead outer chord, skin splice
plate, and outer chord radius filler; repetitive detailed inspections
for cracking of the bulkhead frame web and body skin, and corrective
actions if necessary. The corrective actions include repairing the
crack, or contacting Boeing for repair instructions and repairing if
necessary.
FAA's Determination and Requirements of This Proposed AD
We are proposing this AD because we evaluated all relevant
information and determined the unsafe condition described previously is
likely to exist or develop in other products of the same type design.
This proposed AD would require accomplishing the actions specified in
the service information described previously, except as described
below.
Differences Between Proposed Rule and Service Bulletin
Boeing Service Bulletin 747-53A2305, Revision 2, dated January 15,
2009, specifies to contact the manufacturer for instructions on how to
repair certain conditions, but this proposed AD would require repairing
those conditions in one of the following ways:
Using a method that we approve; or
Using data that meet the certification basis of the
airplane, and that have been approved by the Boeing Commercial
Airplanes Organization Designation Authorization (ODA) whom we have
authorized to make those findings.
Costs of Compliance
We estimate that this proposed AD would affect 160 airplanes of
U.S. registry. The following table provides the estimated costs for
U.S. operators to comply with this proposed AD.
Table--Estimated Costs
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Average labor Cost per Number of U.S.-registered
Action Work hours rate per hour product airplanes Fleet cost
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Inspections: Body skin and skin splice 1 $85 $85 160........................... $13,600.
plate.
Modification: Groups 1-3 \1\........... 180 85 15,300 Up to 27...................... Up to $413,100.
Modification: Groups 1-3 \2\........... 320 85 27,200 Up to 27...................... Up to $734,400.
Modification: Groups 4-8 \3\........... 180 85 15,300 Up to 133..................... Up to $2,034,900.
Modification: Groups 4-7 \4\........... 40 85 3,400 Up to 44...................... Up to $149,600.
Post-Mod LFEC Inspection \5\........... 6 85 510 Up to 160..................... Up to $81,600.
Inspections: Bulkhead Outer Chord \6\.. 4 85 340 Up to 160..................... Up to $54,400.
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\1\ Installation of skin and splice plate doubler for Groups 1-3 airplanes that have not done Boeing Service Bulletin 747-53-2150 or Figure 35 of
Section 53-30-03 of the Boeing 747 Structural Repair Manual.
\2\ Installation of skin and splice plate doubler for Groups 1-3 airplanes that have done Boeing Service Bulletin 747-53-2150 or Figure 35 of Section 53-
30-03 of the Boeing 747 Structural Repair Manual.
\3\ Installation of skin and splice plate doubler for Groups 4-8 airplanes.
\4\ Installation of splice plate doubler for Groups 4-7 airplanes changed before Boeing Alert Service Bulletin 747-53A2305, Revision 2, dated January
15, 2009.
\5\ Inspection for skin cracks around the fasteners at the periphery of the modification doublers.
\6\ Includes inspection of the frame web and body skin.
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 Findings
We 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 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. 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.
You can find our regulatory evaluation and the estimated costs of
compliance in the AD Docket.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
The Proposed Amendment
Accordingly, under the authority delegated to me by the
Administrator, the FAA proposes to amend 14 CFR part 39 as follows:
PART 39--AIRWORTHINESS DIRECTIVES
1. The authority citation for part 39 continues to read as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701.
Sec. 39.13 [Amended]
2. The FAA amends Sec. 39.13 by adding the following new AD:
The Boeing Company: Docket No. FAA-2010-0674; Directorate Identifier
2010-NM-012-AD.
[[Page 39191]]
Comments Due Date
(a) We must receive comments by August 23, 2010.
Affected ADs
(b) None.
Applicability
(c) This AD applies to all The Boeing Company Model 747-100,
747-100B, 747-100B SUD, 747-200B, 747-200C, 747-200F, 747-300, 747-
400, 747-400D, 747-400F, 747SR, and 747SP series airplanes,
certificated in any category.
Subject
(d) Air Transport Association (ATA) of America Code 53:
Fuselage.
Unsafe Condition
(e) This AD results from reports of cracking of the fuselage
skin and adjacent internal skin splice plate at the left and right
nose wheel well aft corners, and the outer chord of the body station
(BS) 400 bulkhead. The Federal Aviation Administration is issuing
this AD to detect and correct cracking of the fuselage skin or
splice plate, which, together with cracking of the bulkhead outer
chord, could result in large skin cracks and subsequent in-flight
rapid decompression of the airplane.
Compliance
(f) You are responsible for having the actions required by this
AD performed within the compliance times specified, unless the
actions have already been done.
Pre-Modification Inspections
(g) For airplanes in Groups 1 through 3, as identified in Boeing
Alert Service Bulletin 747-53A2305, Revision 2, dated January 15,
2009, that have not been modified in accordance with Boeing Service
Bulletin 747-53-2150; have not been repaired in accordance with
Figure 35 of Section 53-30-03 of Boeing 747 Structural Repair Manual
(SRM); and have not been modified in accordance with Boeing Alert
Service Bulletin 747-53A2305: Before the accumulation of 3,000 total
flight cycles, or within 1,500 flight cycles after the effective
date of this AD, whichever occurs later, do an external detailed
inspection for cracks in the body skin around the aft corners of the
nose wheel well, and skin splice plate at the aft corners of the
nose wheel well, in accordance with the Accomplishment Instructions
of Boeing Alert Service Bulletin 747-53A2305, Revision 2, dated
January 15, 2009.
(h) For airplanes in Groups 1 through 3, as identified in Boeing
Alert Service Bulletin 747-53A2305, Revision 2, dated January 15,
2009, that have been modified in accordance with Boeing Service
Bulletin 747-53-2150; or repaired in accordance with Boeing 747
Figure 35 of Section 53-30-03 of Boeing 747 SRM: Within 6,000 flight
cycles after doing the modification or repair, or within 1,500
flight cycles after the effective date of this AD, whichever occurs
later, do an external detailed inspection for cracks in the body
skin around the aft corners of the nose wheel well, and skin splice
plate at the aft corners of the nose wheel well, in accordance with
the Accomplishment Instructions of Boeing Alert Service Bulletin
747-53A2305, Revision 2, dated January 15, 2009.
(i) For airplanes in Groups 4 through 7, as identified in Boeing
Alert Service Bulletin 747-53A2305, Revision 2, dated January 15,
2009, that have not been modified in accordance with Boeing Alert
Service Bulletin 747-53A2305: Prior to the accumulation of 3,000
total flight cycles, or within 1,500 flight cycles after the
effective date of this AD, whichever occurs later, do an external
detailed inspection for cracks in the body skin around the aft
corners of the nose wheel well, in accordance with the
Accomplishment Instructions of Boeing Alert Service Bulletin 747-
53A2305, Revision 2, dated January 15, 2009.
(j) For airplanes in Groups 4 through 7, as identified in Boeing
Alert Service Bulletin 747-53A2305, Revision 2, dated January 15,
2009, that have been modified in accordance with Boeing Service
Bulletin 747-53-2305, dated June 27, 1991; or Revision 1, dated May
22, 1997: Within 1,000 flight cycles after the effective date of
this AD, do a one-time external general visual inspection for steel
cross-shaped doublers, in accordance with the Accomplishment
Instructions of Boeing Alert Service Bulletin 747-53A2305, Revision
2, dated January 15, 2009. If no cross-shaped doublers are
installed, within 1,500 flight cycles after the effective date of
this AD, install cross-shaped doublers, in accordance with the
Accomplishment Instructions of Boeing Alert Service Bulletin 747-
53A2305, Revision 2, dated January 15, 2009.
(k) For airplanes in Group 8, as identified in Boeing Alert
Service Bulletin 747-53A2305, Revision 2, dated January 15, 2009:
Prior to the accumulation of 3,000 total flight cycles, or within
1,500 flight cycles after the effective date of this AD, whichever
occurs later, do an external detailed inspection for cracks in the
body skin around the aft corners of the nose wheel well, in
accordance with the Accomplishment Instructions of Boeing Alert
Service Bulletin 747-53A2305, Revision 2, dated January 15, 2009.
(l) If no crack is found during any inspection required by
paragraph (g), (h), (i), or (k) of this AD, repeat the applicable
inspection specified in paragraph (g), (h), (i), or (k) of this AD
thereafter at intervals not to exceed 1,500 flight cycles, until the
modification specified in paragraph (n) of this AD is accomplished.
(m) If any crack is found during any inspection required by
paragraph (g), (h), (i), (k), or (l) of this AD, before further
flight, modify the aft corners of the nose wheel well by installing
modification doublers and doing all applicable related investigative
and corrective actions, in accordance with the Accomplishment
Instructions of Boeing Alert Service Bulletin 747-53A2305, Revision
2, dated January 15, 2009, except as required by paragraph (t) of
this AD.
Optional Terminating Action
(n) Modification of the aft corners of the nose wheel well by
installing modification doublers and doing all applicable related
investigative and corrective actions, in accordance with the
Accomplishment Instructions of Boeing Alert Service Bulletin 747-
53A2305, Revision 2, dated January 15, 2009, terminates the
repetitive inspections required by paragraph (l) of this AD for the
modified side only. Where Boeing Alert Service Bulletin 747-53A2305,
Revision 2, dated January 15, 2009, specifies to contact Boeing for
appropriate action, repair using a method approved in accordance
with the procedures specified in paragraph (u) of this AD.
Post-Modification Repetitive Inspections
(o) For airplanes on which the modification specified in Boeing
Alert Service Bulletin 747-53A2305, Revision 2, dated January 15,
2009, has been done: At the applicable time specified in paragraph
(o)(1) or (o)(2) of this AD, do an external low frequency eddy
current inspection for skin cracks around the fasteners at the
periphery of the modification doublers, in accordance with the
Accomplishment Instructions of Boeing Alert Service Bulletin 747-
53A2305, Revision 2, dated January 15, 2009.
(1) For airplanes on which the edge row fastener holes common to
the external modification doublers have been zero-timed in
accordance with the Accomplishment Instructions of Boeing Alert
Service Bulletin 747-53A2305, Revision 2, dated January 15, 2009:
Within 15,000 flight cycles after accomplishing the modification, or
within 1,500 flight cycles after the effective date of this AD,
whichever occurs later.
(2) For airplanes on which the edge row fastener holes common to
the external modification doublers have not been zero-timed in
accordance with the Accomplishment Instructions of Boeing Alert
Service Bulletin 747-53A2305, Revision 2, dated January 15, 2009:
Prior to the accumulation of 15,000 total flight cycles, or within
1,500 flight cycles after the effective date of this AD, whichever
occurs later.
(p) If no cracking is found during the inspection required by
paragraph (o) of this AD, repeat the inspection specified in
paragraph (o) of this AD thereafter at intervals not to exceed 1,500
flight cycles.
(q) If any cracking is found during any inspection required by
paragraph (o) or (p) of this AD, before further flight, repair using
a method approved in accordance with the procedures specified in
paragraph (u) of this AD.
Body Station (BS) 400 Bulkhead Outer Chord Inspection
(r) For all airplanes: At the latest of the times specified in
paragraphs (r)(1), (r)(2), and (r)(3) of this AD, do a surface HFEC
for cracking in the BS 400 bulkhead outer chord, skin splice plate,
and outer chord radius filler; and a detailed inspection for
cracking of the bulkhead frame web and body skin; in accordance with
the Accomplishment Instructions of Boeing Alert Service Bulletin
747-53A2305, Revision 2, dated January 15, 2009. If no cracking is
found during any inspection, repeat the inspection one time within
6,000 flight cycles, and thereafter at intervals not to exceed 3,000
flight cycles.
(1) Before the accumulation of 20,000 total flight cycles.
(2) Within 3,000 flight cycles after doing the HFEC inspection
required by AD 2004-
[[Page 39192]]
07-22 R1, Amendment 39-15326, for structural significant item (SSI)
F-4B of the Boeing Document No. D6-35022, ``Supplemental Structural
Inspection Document (SSID) for Model 747 Airplanes,'' Revision G,
dated December 2000.
(3) Within 1,500 flight cycles after the effective date of this
AD.
(s) If any cracking is found during any inspection required by
paragraph (r) of this AD, before further flight, repair in
accordance with the Accomplishment Instructions of Boeing Alert
Service Bulletin 747-53A2305, Revision 2, dated January 15, 2009,
except as required by paragraph (t) of this AD. Within 6,000 flight
cycles after doing the repair, do the inspections specified in
paragraph (r) of this AD, and repeat the inspections thereafter at
intervals not to exceed 3,000 flight cycles.
Service Bulletin Exception
(t) If any cracking is found during any inspection required by
this AD, and Boeing Alert Service Bulletin 747-53A2305, Revision 2,
dated January 15, 2009, specifies to contact Boeing for appropriate
action: Before further flight, repair the crack using a method
approved in accordance with the procedures specified in paragraph
(u) of this AD.
Alternative Methods of Compliance (AMOCs)
(u)(1) The Manager, Seattle Aircraft Certification Office (ACO),
FAA, has the authority to approve AMOCs for this AD, if requested
using the procedures found in 14 CFR 39.19. Send information to
ATTN: Ivan Li, Aerospace Engineer, Airframe Branch, ANM-120S, FAA,
Seattle Aircraft Certification Office, 1601 Lind Avenue, SW.,
Renton, Washington 98057-3356; telephone (425) 917-6437; fax (425)
917-6590. Information may be e-mailed to: [email protected].
(2) To request a different method of compliance or a different
compliance time for this AD, follow the procedures in 14 CFR 39.19.
Before using any approved AMOC on any airplane to which the AMOC
applies, notify your principal maintenance inspector (PMI) or
principal avionics inspector (PAI), as appropriate, or lacking a
principal inspector, your local Flight Standards District Office.
The AMOC approval letter must specifically reference this AD.
(3) An AMOC that provides an acceptable level of safety may be
used for any repair required by this AD if it is approved by the
Boeing Commercial Airplanes Organization Designation Authorization
(ODA) that 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.
Issued in Renton, Washington, on June 29, 2010.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2010-16551 Filed 7-7-10; 8:45 am]
BILLING CODE 4910-13-P