[Federal Register Volume 77, Number 69 (Tuesday, April 10, 2012)]
[Rules and Regulations]
[Pages 21426-21429]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2012-8232]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2011-0915; Directorate Identifier 2011-NM-020-AD;
Amendment 39-17013; AD 2012-07-07]
RIN 2120-AA64
Airworthiness Directives; The Boeing Company Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: We are adopting a new airworthiness directive (AD) for all The
Boeing Company Model 747 airplanes. This AD was prompted by reports of
fractured latch pins found in service; investigation revealed that the
cracking and subsequent fracture were initiated by fatigue and
propagated by a combination of fatigue and stress corrosion. This AD
requires repetitive general visual inspections for broken or missing
latch pins of the lower sills of the forward and aft lower lobe cargo
doors; repetitive detailed inspections for cracking of the latch pins;
and corrective actions if necessary. We are issuing this AD to detect
and correct fractured or broken latch pins, which could result in a
forward or aft lower lobe cargo door opening and detaching during
flight, and consequent rapid decompression of the airplane.
DATES: This AD is effective May 15, 2012.
The Director of the Federal Register approved the incorporation by
reference of certain publications listed in the AD as of May 15, 2012.
ADDRESSES: For service information identified in this AD, contact
Boeing Commercial Airplanes, Attention: Data & Services Management,
P.O. Box 3707, MC 2H-65, Seattle, WA 98124-2207; telephone 206-544-
5000, extension 1; fax 206-766-5680; email [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 AD, the regulatory evaluation,
any comments received, and other information. The address for the
Docket Office (phone: 800-647-5527) is Document Management Facility,
U.S. Department of Transportation, Docket Operations, M-30, West
Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE.,
Washington, DC 20590.
FOR FURTHER INFORMATION CONTACT: Nathan Weigand, Aerospace Engineer,
Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office,
1601 Lind Avenue SW., Renton, Washington 98057-3356; phone: (425) 917-
6428; fax: (425) 917-6590; email: [email protected].
SUPPLEMENTARY INFORMATION:
Discussion
We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR
part 39 to include an AD that would apply to the specified products.
That NPRM was published in the Federal Register on September 1, 2011
(76 FR 54405). That NPRM proposed to require repetitive general visual
inspections for broken or missing latch pins of the lower sills of the
forward and aft lower lobe cargo doors; repetitive detailed inspections
for cracking of the latch pins; and corrective actions if necessary.
[[Page 21427]]
Comments
We gave the public the opportunity to participate in developing
this AD. The following presents the comments received on the proposal
and the FAA's response to each comment.
Request to Withdraw the NPRM (76 FR 54405, September 1, 2011)
United Parcel Service (UPS) asked that we withdraw the NPRM (76 FR
54405, September 1, 2011). UPS stated that there is a lack of
justification for issuing the NPRM and added that it is being issued
based on a report of a fatigue crack in the 17-4PH material latch pins
of the lower cargo door, and the assumption that adjacent latch pins
could also be affected. UPS noted that the latching structures of the
lower forward and aft cargo door each include eight latch pins; those
latch pins are part of a fail-safe design, which should preclude
critical failure with the failure of one element. UPS added that the
Model 747-400 maintenance planning document includes a detailed
inspection of the latch mechanism of the lower cargo door, which
includes the latch pins, at 2 year or 2,000 flight cycle intervals,
whichever occurs first. UPS noted that the NPRM would require
repetitive inspections at 1,600-flight-cycle intervals--a modest
increase in frequency over the existing maintenance program--which has
already been proven successful at detecting damage to adjacent latch
pins. UPS concluded that, based on the extensive fleet history of the
latch pins of these lower cargo doors, with no reports of adjacent pin
failures, the existing maintenance program inspections of the latch
pins are adequate.
We do not agree with the commenter's request to withdraw the NPRM
(76 FR 54405, September 1, 2011). Although the commenter has not
experienced pin failure in service, the manufacturer has found pin
fatigue failure on another airplane of the same type design. Therefore,
we find we must issue this AD to address the identified unsafe
condition on the entire fleet.
The inspections identified in the maintenance planning document are
general visual inspections of the entire door. The inspections required
by this final rule include detailed inspections of the latch pins
themselves. These detailed inspections are the result of the pin
fracturing in service. The fractured pin was the number eight latch pin
on the lower sill of the aft lower lobe cargo door; investigation by
the manufacturer revealed that the crack initiated due to fatigue, and
propagated by a combination of fatigue and stress corrosion. If the
latch pins on the lower sill are not regularly inspected, and broken
latch pins are not replaced, the forward and/or aft cargo door could
open during service, resulting in loss of the cargo door, rapid
decompression, and significant damage to the airplane. No change to the
AD is necessary in this regard.
Request To Clarify Language in Relevant Service Information Section
Boeing asked that the description specified in the ``Relevant
Service Information'' section of the NPRM (76 FR 54405, September 1,
2011) be changed as follows: ``The service bulletin describes
procedures for repetitive detail inspections of latch pins for broken
or missing latch pins of the lower sills of the forward and aft lower
lobe cargo doors; repetitive detailed inspections of the replaced latch
pins for cracked, broken or missing latch pins; and corrective actions
if necessary.'' Boeing stated that Boeing Alert Service Bulletin 747-
53A2835, dated October 28, 2010, necessitates that a detailed
inspection be done on all pins (including previously replaced pins).
Boeing added that the detailed inspection is for cracks, and the
general visual inspection is to look for the broken and missing pins.
Boeing notes that paragraph (g) of the NPRM provides the correct
description of the inspections specified in the service bulletin.
We acknowledge the commenter's concern and agree that the language
could be clarified somewhat; however, since that section of the
preamble does not reappear in the final rule, no change to this AD is
necessary in this regard.
Request To Include Revision 1 of the Referenced Service Bulletin
Boeing also asked that Boeing Alert Service Bulletin 747-53A2835,
Revision 1, dated December 8, 2011, be included in the NPRM (76 FR
54405, September 1, 2011) for accomplishing certain actions. Boeing
Alert Service Bulletin 747-53A2835, dated October 28, 2010, was
referred to as the appropriate source of service information for
accomplishing the actions specified in the NPRM. Boeing added that
Boeing Alert Service Bulletin 747-53A2835, Revision 1, dated December
8, 2011, is scheduled for FAA-approval, and includes a latch pin
modification and post-modification inspection to address the safety
issue.
We have reviewed Boeing Alert Service Bulletin 747-53A2835,
Revision 1, dated December 8, 2011, and agree to include it in this
final rule as an additional source of service information. Boeing Alert
Service Bulletin 747-53A2835, Revision 1, dated December 8, 2011,
reduces an existing compliance time, adds a latch pin modification, and
repetitive post-modification inspections. We are including the actions
in Boeing Alert Service Bulletin 747-53A2835, Revision 1, dated
December 8, 2011, as optional in order to avoid delaying issuance of
the AD. We have revised paragraph (g) of this AD accordingly. We are
currently considering additional rulemaking to require the modification
and post-modification inspections.
Conclusion
We reviewed the relevant data, considered the comments received,
and determined that air safety and the public interest require adopting
the AD with the changes described previously--and minor editorial
changes. We have determined that these minor changes:
Are consistent with the intent that was proposed in the
NPRM (76 FR 54405, September 1, 2011) for correcting the unsafe
condition; and
Do not add any additional burden upon the public than was
already proposed in the NPRM (76 FR 54405, September 1, 2011).
We also determined that these changes will not increase the
economic burden on any operator or increase the scope of the AD.
Costs of Compliance
We estimate that this AD affects 228 airplanes of U.S. registry.
We estimate the following costs to comply with this AD:
Estimated Costs
--------------------------------------------------------------------------------------------------------------------------------------------------------
Action Labor cost Parts cost Cost per product Cost on U.S. operators
--------------------------------------------------------------------------------------------------------------------------------------------------------
Inspection........................... 3 work-hours x $85 per $0 $255 per inspection $58,140 per inspection cycle.
hour = $255 per cycle.
inspection cycle.
--------------------------------------------------------------------------------------------------------------------------------------------------------
[[Page 21428]]
We estimate the following costs to do any necessary replacements/
modifications that would be required based on the results of the
required inspection. We have no way of determining the number of
aircraft that might need these actions:
On-Condition Costs
----------------------------------------------------------------------------------------------------------------
Cost per
Action Labor cost Parts cost product
----------------------------------------------------------------------------------------------------------------
Replacement of latch pins..................... 8 work-hours x $85 per hour = $680.... $0 $680
Modification of latch fittings................ 36 hours x $85 per work-hours = $3,060 0 3,060
----------------------------------------------------------------------------------------------------------------
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
This AD will not have federalism implications under Executive Order
13132. This AD 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.
For the reasons discussed above, I certify that this AD:
(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),
(3) Will not affect intrastate aviation in Alaska, and
(4) 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.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
Accordingly, under the authority delegated to me by the
Administrator, the FAA amends 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. The FAA amends Sec. 39.13 by adding the following new airworthiness
directive (AD):
2012-07-07 The Boeing Company: Amendment 39-17013; Docket No. FAA-
2011-0915; Directorate Identifier 2011-NM-020-AD.
(a) Effective Date
This AD is effective May 15, 2012.
(b) Affected ADs
None.
(c) Applicability
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.
(d) Subject
Joint Aircraft System Component (JASC)/Air Transport Association
(ATA) of America Code 53: Fuselage.
(e) Unsafe Condition
This AD was prompted by reports of fractured latch pins found in
service; investigation revealed that the cracking and subsequent
fracture were initiated by fatigue and propagated by a combination
of fatigue and stress corrosion. We are issuing this AD to detect
and correct fractured or broken latch pins, which could result in a
forward or aft lower lobe cargo door opening and detaching during
flight, and consequent rapid decompression of the airplane.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Inspections
Before the accumulation of 6,000 total flight cycles, or within
1,000 flight cycles after the effective date of this AD, whichever
occurs later: Do a general visual inspection for broken or missing
latch pins of the lower sills of the forward and aft lower lobe
cargo doors, and a detailed inspection for cracking of the latch
pins, in accordance with paragraph 3.B., ``Work Instructions,'' of
Boeing Alert Service Bulletin 747-53A2835, dated October 28, 2010;
or Boeing Alert Service Bulletin 747-53A2835, Revision 1, dated
December 8, 2011. Repeat the inspections thereafter at the
applicable intervals specified in paragraph 1.E., ``Compliance,'' of
Boeing Alert Service Bulletin 747-53A2835, dated October 28, 2010;
or Boeing Alert Service Bulletin 747-53A2835, Revision 1, dated
December 8, 2011. Before further flight, do all applicable
corrective actions, in accordance with paragraph 3.B., ``Work
Instructions,'' of Boeing Alert Service Bulletin 747-53A2835, dated
October 28, 2010; or Boeing Alert Service Bulletin 747-53A2835,
Revision 1, dated December 8, 2011.
(h) Special Flight Permits
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 airplane
can be modified (if the operator elects to do so), provided the
cabin is not pressurized.
(i) Alternative Methods of Compliance (AMOCs)
(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. In accordance with 14
CFR 39.19, send your request to your principal inspector or local
Flight Standards District Office, as appropriate. If sending
information directly to the manager of the ACO, send it to the
attention of the person identified in the Related Information
section of this AD. Information may be emailed to: [email protected].
(2) Before using any approved AMOC, notify your appropriate
principal inspector, or lacking a principal inspector, the manager
of the local flight standards district office/certificate holding
district office.
(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 ODA that has been authorized by the
Manager, Seattle
[[Page 21429]]
ACO, to make those findings. For a repair method to be approved, the
repair must meet the certification basis of the airplane.
(j) Related Information
For more information about this AD, contact Nathan Weigand,
Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft
Certification Office, 1601 Lind Avenue SW., Renton, Washington
98057-3356; phone: (425) 917-6428; fax: (425) 917-6590; email:
[email protected].
(k) Material Incorporated by Reference
You must use the following service information to do the actions
required by this AD, unless the AD specifies otherwise. The Director
of the Federal Register approved the incorporation by reference
(IBR) under 5 U.S.C. 552(a) and 1 CFR part 51 of the following
service information.
(1) Boeing Alert Service Bulletin 747-53A2835, dated October 28,
2010.
(2) Boeing Alert Service Bulletin 747-53A2835, Revision 1, dated
December 8, 2011.
(3) For service information identified in this AD, contact
Boeing Commercial Airplanes, Attention: Data & Services Management,
P.O. Box 3707, MC 2H-65, Seattle, WA 98124-2207; telephone 206-544-
5000, extension 1; fax 206-766-5680; email [email protected];
Internet https://www.myboeingfleet.com.
(4) 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.
(5) You may also review copies of the service information that
is incorporated by reference 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: http://www.archives.gov/federal-register/cfr/ibr-locations.html.
Issued in Renton, Washington, on March 28, 2012.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2012-8232 Filed 4-9-12; 8:45 am]
BILLING CODE 4910-13-P