AD 2015-14-09
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | The Boeing Company | 747-100 Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 747-100B Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 747-100B SUD Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 747-200B Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 747-200C Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 747-200F Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 747-300 Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 747-400 Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 747-400D Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 747-400F Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 747-8 Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 747-8F Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 747SP Series | Airworthiness Directives; The Boeing Company Airplanes |
| aircraft | The Boeing Company | 747SR Series | Airworthiness Directives; The Boeing Company Airplanes |
Unsafe Condition
Intermodal containers, when loaded as cargo in the offset method, can shift during flight gust loads and impact adjacent fuselage frames, leading to structural failure of the aft fuselage and potential in-flight breakup.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Revise the airplane flight manual (AFM) to incorporate limitations for carrying intermodal containers nominally sized at 20 feet long, 8 feet wide, and 8.5 feet tall, or ISO 668-1CC containers, unless they are concentrically loaded on a pallet and restrained in accordance with the FAA-approved Weight and Balance Manual (WBM) or WBM supplement.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Before further flight
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
The Boeing Company Model 747 airplanes equipped with a main deck side cargo door (MDSCD).
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
We are adopting a new airworthiness directive (AD) for The Boeing Company Model 747 airplanes equipped with a main deck side cargo door (MDSCD). This AD was prompted by recent testing that indicates that intermodal containers, when loaded as cargo, under certain flight- load conditions, can shift and impact the adjacent fuselage frames. This AD requires revising the airplane flight manual (AFM) to incorporate limitations for carrying certain payloads. We are issuing this AD to prevent intermodal containers loaded in the offset method from shifting during flight gust loads and damaging fuselage frames, which could lead to the structural failure of the aft fuselage in flight and subsequent in-flight breakup of the airplane.
Applicability Source Text
Show captured applicability text from the source AD
(c) Applicability
This AD applies to 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, 747SP, 747-8F, and 747-8 series airplanes,
certificated in any category, equipped with a main deck side cargo
door (MDSCD).
Document Text
Show stored source text (verify against official source)
[Federal Register Volume 80, Number 133 (Monday, July 13, 2015)]
[Rules and Regulations]
[Pages 39943-39950]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2015-17031]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2014-0780; Directorate Identifier 2014-NM-168-AD;
Amendment 39-18207; AD 2015-14-09]
RIN 2120-AA64
Airworthiness Directives; The Boeing Company Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
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SUMMARY: We are adopting a new airworthiness directive (AD) for The
Boeing Company Model 747 airplanes equipped with a main deck side cargo
door (MDSCD). This AD was prompted by recent testing that indicates
that intermodal containers, when loaded as cargo, under certain flight-
load conditions, can shift and impact the adjacent fuselage frames.
This AD requires revising the airplane flight manual (AFM) to
incorporate limitations for carrying certain payloads. We are issuing
this AD to prevent intermodal containers loaded in the offset method
from shifting during flight gust loads and damaging fuselage frames,
which could lead to the structural failure of the aft fuselage in
flight and subsequent in-flight breakup of the airplane.
DATES: This AD is effective August 17, 2015.
Examining the AD Docket
You may examine the AD docket on the Internet at <a href="http://www.regulations.gov">http://www.regulations.gov</a> by searching for and locating Docket No. FAA-2014-
0780; 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 Docket 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: Steven C. Fox, Senior Aerospace
Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft
Certification Office (ACO), 1601 Lind Avenue SW., Renton, WA 98057-
3356; phone: 425-917-6425; fax: 425-917-6590; email:
<a href="/cdn-cgi/l/email-protection#fe8d8a9b889b90d0989186be989f9fd0999188"><span class="__cf_email__" data-cfemail="e596918093808bcb838a9da5838484cb828a93">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Discussion
The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 by adding an AD that would apply to The Boeing Company
Model 747 airplanes equipped with an MDSCD. The NPRM published in the
Federal Register on December 1, 2014 (79 FR 71037). The NPRM was
prompted by recent testing, which indicates that intermodal containers,
when loaded as cargo, under certain flight-load conditions, can shift
and impact the adjacent fuselage frames. The NPRM proposed to require
revising the AFM to incorporate limitations for carrying certain
payloads. We are issuing this AD to prevent intermodal containers
loaded in the offset method from shifting during flight gust loads and
damaging fuselage frames, which could lead to the structural failure of
the aft fuselage in flight and subsequent in-flight breakup of the
airplane.
Background
Intermodal containers are common in the cargo shipping industry and
transported by ships, trains, and trucks. The focus of this final rule
is an intermodal container that is nominally 20 feet long, 8 feet wide,
and 8.5 feet tall. This nominally sized intermodal container includes
the dimensions of an International Organization for Standardization
(ISO) container ISO 668-1CC. Because the intermodal containers
themselves do not meet the requirements of FAA Technical Standard Order
TSO-C90D, ``Cargo Pallets, Nets and Containers (Unit Load Devices),''
the lower surface on these intermodal containers is incompatible with
most airplane cargo-loading systems (CLSs). These intermodal
containers, however, can be concentrically loaded on an FAA-approved
TSO-C90D pallet with a certified net combination and loaded in the
center of the airplane, restrained by the CLS or a series of straps
connected to the aircraft structure in accordance with the airplane's
FAA-approved Weight and Balance Manual (WBM) procedures for cargo that
is not a Unit Load Device (ULD).
The WBM is part of the Operating Limitations section of the
Airplane Flight Manual (AFM). In accordance with 14 CFR 21.41, the
Operating Limitations are part of the airplane type certificate and,
therefore, can be modified only by changing that certificate; that is,
by obtaining an amended or supplemental type certificate. Revisions to
the AFM are approved as AFM supplements, and the approval is based on a
finding that, with the AFM revisions, the airplane continues to meet
the applicable airworthiness standards. Operators are required to
comply with the Operating Limitations by 14 CFR 91.9(a).
The FAA has become aware that some operators, both domestic and
foreign, are not loading these containers in the center of the
airplane, but rather in the standard left and right pallet positions.
When loaded in this manner, the 8-foot, 6-inch, height of the
intermodal container interferes with the fuselage, so some operators
have been transporting these intermodal containers shifted inboard, off
of the FAA-approved TSO pallets, and attached to the pallet only with a
net and/or straps. This method of transport is referred to as the
``offset method.'' The practice of offsetting the intermodal containers
results in the certified pallet-net combination having slack in the net
by the amount of the offset. FAA observations have found the offset for
intermodal containers is as much as 9 inches, with the corresponding 9
inches of slack in the TSO pallet net.
Although additional cargo straps have been used to restrain the
intermodal containers to the pallets, the FAA determined that these
straps are not effective, and the intermodal container can shift in
flight. In 2013, a U.S. cargo operator requested permission from the
FAA to carry intermodal containers on Boeing Model 747 airplanes using
the offset method--similar to procedures used by other U.S. and non-
U.S. air carriers. Based on the FAA's review of the offset method, it
denied the operator's request.
Industry Testing of the Offset Method
In March 2014, some U.S. cargo operators and Boeing conducted a
series of full-scale tests, witnessed by the FAA, to demonstrate that
carrying intermodal containers by the offset method could be shown safe
and compliant to the applicable regulations. The test procedures were
developed by engineers from Boeing and some U.S. cargo operators, and
were intended to show compliance for flight loads on Model 747
airplanes only. The results produced CLS failures and excessive
deflections. The preliminary test results confirmed the FAA's safety
concerns.
[[Page 39944]]
U.S. operators and Boeing conducted additional testing to
demonstrate that carrying intermodal containers by the offset method
could be shown to be safe and compliant with applicable regulations.
This testing used methods from National Aerospace Standard (NAS) 3610,
with maximum payloads that were reduced from those tested previously.
The intent was for Boeing to use the test data to develop an
appropriate loading method that could be incorporated into the Boeing
Model 747 WBMs. The certified pallet net was not used because previous
testing showed it ineffective in restraining the ISO container as the
offset of the container on the pallet introduces slack in the net, with
the container essentially free to move laterally in the airplane by the
amount of the offset.
Significant engineering resources were applied, and a complex
method of strapping installation and procedures and sequence for
tightening the straps was developed to preclude the excessive
deflections experienced during earlier tests. While a few load cases
were successful, some had very small margins (precluding any reduction
of the complexity of the nearly 100 straps required). The testing was
halted after attempts to substantiate vertical loading repetitively
overloaded the forward and aft CLS restraint locks, and the proposed
cargo restraining method was deemed unviable.
FAA engineering from the Transport Airplane Directorate has been
extensively involved in the testing of offset loading methods for
intermodal containers with the objective to determine and document a
safe and compliant methodology that could be the basis for a Boeing
Model 747 Weight and Balance Supplement for airline use worldwide.
Testing to date indicates this objective has not been met.
When positioned in accordance with the WBMs, an intermodal
container is secured to the CLS pallet along its entire length by
straps and netting. Offsetting the container has the effect of creating
slack in the net and straps, except at the ends of the container. As a
result, when gust loads are encountered, most of the loads are
transferred to the locks at the ends of the container and are not
shared with the locks in the middle. This uneven loading has the effect
of exceeding the structural capability of the locks at the ends of the
container. This phenomenon quickly failed the forward and aft CLS locks
during vertical testing, as confirmed by both sets of industry testing.
At this time, there is no offset method for restraining intermodal
containers that has been demonstrated to be safe and compliant.
Safety Issue
The current practice of carrying an intermodal container by the
offset method is not currently permitted by the Boeing Model 747 WBMs.
A series of tests has verified that an intermodal container, under
certain flight-load conditions, can shift in both the outboard and
vertical directions. This shift by the intermodal container can damage
as many as ten fuselage frames per container position during flight,
leading to the structural failure of the aft fuselage in flight, and
subsequent in-flight breakup of the airplane.
Normally, the FAA does not issue ADs to address non-compliance with
existing regulations. But because of the widespread nature of these
practices, the FAA has determined that issuing an AD is the most
effective means of addressing this unsafe condition.
This final rule, therefore, revises the Operating Limitations
section of the FAA-approved AFM to incorporate limitations on carrying
certain payloads. As revised, the AFM expressly states the pre-existing
prohibition on carriage of either (1) intermodal containers nominally
sized at 20 feet long, 8 feet wide, and 8.5 feet tall, or (2) ISO 668-
1CC containers, if those containers are not concentrically loaded on a
pallet and restrained to the aircraft in accordance with the FAA-
approved WBMs or WBM supplement.
Explanation of Changes to the Final Rule
Since issuing the NPRM (79 FR 71037, December 1, 2014), the FAA has
learned that some operators might regard changes that they make to the
Boeing Weight and Balance Manual to be ``FAA approved,'' even though
the operators have not sought FAA approval through the supplemental
type certificate process, as described in the NPRM. To clarify that
only changes made through the type certificate process are considered
``FAA approved,'' we have revised the language of the final rule to
specifically reference the FAA-approved Boeing type certificate Weight
and Balance Manual or a Supplemental Weight and Balance Manual approved
through the supplemental type certificate process. Given the comments
opposing the proposed AD discussed below, it is apparent that the
commenters were not confused on this point. Nevertheless, this
clarification will prevent confusion for any operator in the future.
Comments
We gave the public the opportunity to participate in developing
this AD. The following presents the comments received on the NPRM (79
FR 71037, December 1, 2014) and the FAA's response to each comment.
Support for the NPRM (79 FR 71037, December 1, 2014)
The Air Line Pilots Association, International (ALPA), stated that
they fully support the intent of the NPRM (79 FR 71037, December 1,
2014).
Request To Withdraw NPRM (79 FR 71037, December 1, 2014): Intermodal
Containers Are Permitted by WBMs
The Cargo Airline Association, Atlas Air, International Air
Transport Association (IATA), National Air Carrier Association (NACA),
Kalitta Air, LLC (Kalitta), and the Michigan Senate requested that we
withdraw the NPRM (79 FR 71037, December 1, 2014). The commenters
asserted that offset intermodal containers are permitted by the Boeing
Model 747 WBMs. The commenters also asserted that the Boeing Model 747
WBMs permit the restraint of an intermodal container and pallet
assembly with cargo restraint straps only to the pallet (and not the
airplane itself), whether or not the container is offset. The
commenters concluded that the NPRM statement indicating that ``the
current practice of carrying an intermodal container by the offset
method is not permitted by the Boeing Model 747 Weight and Balance
Manual'' is incorrect and completely at odds with Boeing's WBMs. The
commenters limited their views to only those Model 747 WBMs created by
Boeing.
We disagree with the request. Since the commenters did not address
any supplemental WBMs produced by holders of supplemental type
certificates (STCs), our response is limited to a discussion of the
Boeing Model 747 WBMs. As explained below, contrary to the commenters'
assertions, the Boeing Model 747 WBMs do not permit loading of either
offset intermodal containers or intermodal containers strapped only to
the pallet.
As discussed in the NPRM, in accordance with section 21.41 of the
Federal Aviation Regulations (14 CFR 21.41), the operating limitations
are part of the airplane's type certificate (TC). The operating
limitations specified in the Boeing Model 747 WBMs are established by
the TC holder at the time of type certification as necessary to
demonstrate that the airplane, when properly loaded, will comply with
all
[[Page 39945]]
applicable airworthiness requirements. One of these requirements is to
demonstrate the capability of the airplane to continue safe operation
when subjected to a range of structural loads that may be encountered
during operations (14 CFR 25.1519). The Boeing Model 747 WBMs provide
operators with detailed instructions, including restrictions, on how
the airplane may be loaded such that after loading and during flight
the airplane still is in compliance with the operating limitations.
The Boeing Model 747 cargo airplanes are equipped with a cargo
loading system, which is part of the airplane's type design and
consists of roller trays, guides, latches, and locks that restrain the
cargo to the airplane for flight loads. A Unit Load Device (ULD) is a
device for grouping and retaining cargo for transit. The Boeing Model
747 WBMs include, as part of the operating limitations, instructions
that identify which ULDs may be loaded into the airplane's cargo
loading system on the main cargo deck of the airplane without
additional restraint to the airplane's structure.
Although the actual wording in these manuals varies slightly, all
Boeing Model 747 WBMs require that, to be carried on the main deck
without additional restraints, ``certified'' ULDs must conform to FAA
Technical Standard Order (TSO) TSO-C90, ``Cargo Pallets, Nets, and
Containers,'' or to National Aerospace Standard (NAS) 3610 (``Cargo
Unit Load Devices--Specification For''), the document the TSO
references as a requirement. NAS 3610 is an industry standard used to
define the required configuration and certification testing for various
ULDs.
The types of certified ULDs identified in the Boeing Model 747 WBMs
are NAS 3610-compliant containers) and pallet-net combinations.
Containers identified in NAS 3610 are attached directly to the
airplane's cargo loading system. Intermodal containers, which are the
subject of this AD, do not meet the standard for NAS 3610 containers.
For the pallet-net combinations, the cargo is restrained to the pallet
by a net that attaches to the pallet on all four sides and covers the
cargo. Under the Boeing Model 747 WBMs, an intermodal container may be
loaded into a certified pallet-net combination ULD as long as the
intermodal container is located within the perimeter of the pallet.
However, as explained in the NRPM, an intermodal container offset from
its pallet introduces slack in the corresponding net and, therefore,
does not meet the requirements of NAS 3610 and is not allowed as a
certified ULD under the Boeing Model 747 WBMs.
The Boeing Model 747 WBMs require that all cargo other than the
identified ULDs be restrained to the airplane by straps in accordance
with instructions specified in the WBMs. The Boeing Model 747 WBMs
provide detailed instructions that define the specific locations where
straps must be attached to the airplane structure, as well as other
information such as maximum weights to be restrained at each location.
With one recently approved exception,\1\ nothing in the Boeing Model
747 WBMs or in NAS 3610 allows for the use of straps to restrain cargo
to the ULD pallet itself.
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\1\ The FAA recently approved a supplement to the Boeing Model
747 WBMs that allows strapping of cargo to a pallet under limited
circumstances that are not relevant to this rulemaking.
---------------------------------------------------------------------------
Therefore, contrary to the commenters' assertions, the Boeing Model
747 WBMs do not permit loading of either offset intermodal containers
or intermodal containers strapped only to the pallet. Furthermore,
neither Boeing nor any of the commenters have shown that the airplane,
when loaded with offset containers, complies with the applicable
airworthiness standards of part 25. As discussed in the NPRM, any such
showing would have to be done by a change to the type certificate in
accordance with FAA Order 8110.4C.
We have not changed this final rule regarding this issue.
Opposition to NPRM (79 FR 71037, December 1, 2014): History of Safety
IATA, Kalitta, and the Michigan Senate opposed the NPRM (79 FR
71037, December 1, 2014), stating that it does not refer to any
incident or accident. The commenters reported that for more than 40
years, intermodal containers loaded as offset cargo have been carried
with no damage to frames.
We disagree with the commenters' conclusion. As discussed in the
NRPM, industry and Boeing testing have shown that offset loading of
intermodal containers can allow the cargo to shift, which would be
unsafe under certain flight load conditions. (The AD docket contains a
Boeing presentation summarizing these test results.) The purpose of
this AD, and all ADs, is to correct an unsafe condition regardless of
whether that condition has caused accidents in the past.
Furthermore, in general, the shifting of cargo in flight has
resulted in numerous incidents and accidents. For example, on August 7,
1997, Fine Air Flight 101 crashed shortly after takeoff from Miami
because cargo shifted. Similarly, all evidence indicates that on April
29, 2013, National Airlines Flight 102 crashed shortly after takeoff
from Bagram, Afghanistan, because cargo shifted. We have not changed
this final rule regarding this issue.
Request To Withdraw NPRM (79 FR 71037, December 1, 2014): Proposal
Based on Unfounded Principles
Atlas Air, the Cargo Airline Association, Kalitta, NACA, and United
Parcel Service (UPS) requested that we withdraw the NPRM (79 FR 71037,
December 1, 2014) because it misstates an important principle. The
commenters noted that the NPRM stated that ``the Weight and Balance
Manual is part of the Operating Limitations section of the Airplane
Flight Manual (AFM).'' The commenters asserted that a reader could
infer from this that all content in an airplane manufacturer's WBMs is
part of the Operating Limitations section of the AFM. The commenters
contended that since Boeing's Model 747 WBMs contain operating
procedures in addition to operating limitations, only portions of the
WBMs are part of the Operating Limitations section of the AFM. The
commenters also noted that Boeing frequently revises the WBMs, and when
Boeing does so, Boeing does not amend the type certificate, which the
commenters assert would be ``a laborious process.''
We agree with the commenters' proposition that not all of a
manufacturer's WBM is necessarily part of the AFM operating
limitations, but we disagree with their assertion that FAA-approved
loading instructions are not operating limitations. We also disagree
with the commenters' request to change the rule as originally proposed.
As provided in 14 CFR 25.1583(c), the WBM is referenced in the AFM and
contains operating limitations approved under that section. Section
25.1583(c)(2) requires that the AFM include loading instructions that
are necessary to ensure loading of the airplane within the weight and
center of gravity limits, and to maintain the loading within these
limits in flight. While the Boeing Model 747 WBMs may include
information other than limitations, the loading instructions discussed
previously are limitations, and the FAA approved the Boeing Model 747
WBMs based on a determination that, as operating limitations, these
instructions were adequate to meet the requirements of 14 CFR 25.1583.
For many years the FAA has recognized that both the weight and
balance information and the loading instructions are operating
limitations.
[[Page 39946]]
For example, in FAA Advisory Circular (AC) 25.1581-1, dated July 14,
1997 (http://rgl.faa.gov/Regulatory_and_Guidance_Library/
rgAdvisoryCircular.nsf/0/cb7efbdd420bd265862569b3005479d7/$FILE/AC25-
1581-1.pdf), the FAA stated, in Section 2b(1), ``Any limitations on
airplane loading associated with the stated weight limitations must be
included in the AFM or addressed in a separate weight and balance
document.''
These loading instructions are the procedures that Boeing
determined were necessary to load and restrain cargo for flight loads;
these instructions are used to show compliance with the design
requirements for the airplane, including the structural capabilities of
the cargo loading system, airplane floors, and fuselage, and are
therefore operating limitations. The types of ULDs and methods to
restrain cargo are limitations provided in the Boeing Model 747 WBMs
that ensure the airplane structure is not overloaded throughout the
airplane's defined flight envelope. For this reason, additions to the
approved list of ULDs or deviations to the structural tie-down
locations that are not approved through the type certification process
result in noncompliant and unknown conditions that could result in the
structural overload to the airplane under certain flight loads.
Adopting the commenters' argument that these loading instructions
are not limitations and, therefore, not mandatory would lead to the
anomalous result that, while the weight and balance limitations are
mandatory, the means to ensure they are complied with are not.
Regarding the commenter's statement that Boeing frequently changes
the WBMs, those changes are in fact changes to the type certificate,
which are approved by the FAA or its designees. We have not changed
this final rule regarding this issue.
Opposition to NPRM (79 FR 71037, December 1, 2014): AD Approach Is
Overly Broad and Burdensome
Kalitta asserted that the NPRM (79 FR 71037, December 1, 2014)
appears to assume that the offset configuration is already forbidden
because it is not explicitly provided for in the Boeing Model 747
WBMs--i.e., unless the loading of a specific ULD or type of cargo and
configuration is specifically defined in the Boeing Model 747 WBMs, it
is prohibited. The commenter asserted that this is a novel
interpretation and is unduly restrictive, contrary to accepted and
normal air carrier operations and contrary to the FAA's own guidance
material, and will have a significant and far-reaching operational and
economic impact on all U.S. air carriers in the future, no matter what
kind of aircraft they operate. The commenter stated that the FAA should
carefully consider the ramifications of adopting a policy of ``what is
not explicitly allowed is forbidden.'' The commenter stated that this
approach reaches well beyond the particular matter at hand, and can
create a regulatory environment that stifles innovation, and requires a
manufacturer or the FAA to think in advance of every kind of operation
that may possibly arise, and provide for it in the regulatory
documents. According to the commenter, this would create an impossible
burden on government and industry both.
We disagree with the commenter's assertions. As discussed
previously, the Boeing Model 747 WBMs define safe and compliant methods
for loading the airplane. The Boeing Model 747 WBMs provide the
instructions required by 14 CFR 25.1583, enabling the operators to load
and restrain cargo in a manner that does not permit the shifting of
cargo during flight, which could cause damage to the airplane or result
in a configuration leading to the loss of control of the airplane. As
discussed previously, these instructions are considered operating
limitations. Operation of the airplane beyond those limits is not
permitted by the Boeing Model 747 WBMs. Section 121.135(b)(21) requires
operators to include in their manuals methods and procedures for
maintaining the aircraft weight and center of gravity within approved
limits. The unsafe condition addressed in this AD is a result of
operators having adopted methods and procedures that are contrary to
the WBM instructions and, as a result, not within the approved limits.
Innovations are acceptable provided they meet the limits specified
in the WBMs. Innovations that exceed those limits must be approved as
changes to the WBM, as required by subparts D and E of 14 CFR part 21,
and as provided in FAA Order 8110.4C, dated March 28, 2007 (http://
rgl.faa.gov/Regulatory_and_Guidance_Library/rgOrders.nsf/0/
d21193af2d37a8ba862570ab0054c104/$FILE/8110.4C_CHG5_Incorporated.pdf),
which describes the process for obtaining FAA approval for changes to
the airplane's type certificate. We have not changed this final rule
regarding this issue.
Opposition to NPRM (79 FR 71037, December 1, 2014): Unrealistic Cost
Estimate
Cargo Airline Association, Atlas Air, IATA, NACA, and Kalitta
alleged that the FAA's determination of the estimated costs to comply
with the NPRM (79 FR 71037, December 1, 2014) is fundamentally flawed
because it is based on an unreasonably narrow view of the AD's costs
and, as a result, the FAA's cost estimate is unrealistically low. The
commenters concluded that the AD, if issued as proposed, would have
significant, multi-million dollar cost consequences and competitiveness
implications for all U.S. Model 747 freighter operators, with no
appreciable countervailing safety benefits. In particular, the
commenters stated that when intermodal containers are carried in the
offset manner, additional cargo can be carried in the adjacent cargo
pallet positions. The commenters further asserted that if the
intermodal containers are required to be restrained to the airplane,
the necessary restraint configuration would preclude the carriage of
the adjacent positions and that revenue from the adjacent positions
would be lost.
We do not agree with the commenters' allegations. As discussed
previously and in the NPRM, carriage of offset containers is contrary
to the limitations in the Boeing Model 747 WBMs and, therefore,
contrary to 14 CFR 91.9(a). The intent of this AD is to require
operators to revise their AFMs in a manner that eliminates this
already-noncompliant practice, which we have determined creates an
unsafe condition. Based on the FAA's determination that this conduct is
noncompliant, the FAA has already directed individual operators not to
carry intermodal containers using the offset method.\2\ Issuance of
this AD fulfills the FAA's international obligations of informing
foreign airworthiness authorities of the existence of this unsafe
condition and of the appropriate means for addressing it, as well as
reinforces the determination discussed previously.
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\2\ For example, a letter dated May 2, 2014, directing Kalitta
to discontinue this practice is included in the docket.
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Moreover, the cost associated with ceasing noncompliant conduct is
not attributable to this AD, regardless of how profitable that conduct
may be. The cost information in AD actions describes only the direct
costs of the specific action required by the AD--in this case, revising
the AFM. We recognize that, in doing the actions required by an AD,
operators might incur operational costs in addition to the direct
costs. The cost
[[Page 39947]]
analysis in AD rulemaking actions, however, typically does not include
incidental or operational costs such as the time required for planning
or other administrative actions. Our analysis also would not include
possible revenue lost as a result of ending noncompliant operations.
The FAA recognizes that the reason operators carry intermodal
containers in violation of the Boeing Model 747 WBM limitations is that
it is more profitable. The amount of revenue that could be generated
when cargo is carried in a noncompliant manner is almost impossible to
calculate.
We have not changed this final rule regarding this issue.
Opposition to NPRM (79 FR 71037, December 1, 2014): Economic Impact on
Small Entities
Kalitta and the Michigan Senate stated that the NPRM (79 FR 71037,
December 1, 2014) fails to account for impact on small entities because
most airlines that would be affected by the NPRM have fewer than 1,500
employees. The commenters stated that this is a significant economic
impact by loss of revenue.
As discussed previously, we have determined that there is no
significant impact on air carriers in the United States because loading
offset intermodal containers is contrary to the limitations of the
Boeing Model 747 WBMs, and is therefore already prohibited. That is,
whether or not this final rule is issued, the practice of carrying
intermodal containers in the offset method is not permitted for U.S.
air carriers as it is a noncompliant and unsafe practice.
Opposition to NPRM (79 FR 71037, December 1, 2014): Inadequate Testing
Cargo Airline Association, Atlas Air, NACA, IATA, Kalitta, and the
Michigan Senate criticized the tests discussed in the NPRM (79 FR
71037, December 1, 2014) that confirmed the FAA's determination that
loading containers in the offset position is an unsafe condition,
arguing they were unrealistic or inconclusive. In general, the
commenters claimed that the tests used configurations of intermodal
containers and their restraints that are different from those used in
service and applied pass-fail criteria that were unnecessarily
stringent.
We do not agree that the tests were unrealistic or inadequate. A
detailed discussion of the commenters' technical concerns regarding the
tests is included in the AD docket.
In short, the tests of offset intermodal containers discussed in
the NPRM included a range of configurations, including those that the
participants, including Boeing and cargo operators, considered
necessary to show compliance to the regulations, and even a scenario
using empty containers. The tests demonstrated that offset intermodal
containers would not be restrained securely for flight loads such as
heavy turbulence. As discussed previously, loading offset intermodal
containers is already contrary to the limitations of the Boeing Model
747 WBMs. If commenters believe that they can show compliance with the
applicable part 25 airworthiness standards using offset containers,
they may apply for supplemental type certificates (STCs). Any such
STCs, if granted, would also be considered as a possible alternative
method of compliance (AMOC) to this AD.
Request To Delay Issuance of AD Pending Acceptance of New Testing
Kalitta, NACA, and the Michigan Senate requested that we delay
issuing a final AD because new testing by Kalitta shows that the offset
configuration can be used without posing a threat to safety.
We disagree with the request. The test process and results have not
been submitted to the FAA for approval. However, if the testing is
completed and approved, it may serve as the basis for a new STC, which
we would then consider as a possible AMOC to this AD. We have not
changed this final rule regarding this issue.
Request To Withdraw NPRM (79 FR 71037, December 1, 2014): Unnecessary
Based on New Operating Specifications
Cargo Airline Association, IATA, Kalitta, NACA, and the Michigan
Senate requested that we withdraw the NPRM (79 FR 71037, December 1,
2014). IATA recently issued Operating Specification (OS) 6/13 (ULD:
Operating Specifications). According to the commenters, IATA OS 6/13
provides guidance for safely handling multiple configurations of offset
sea-land (intermodal) containers and ensuring the effectiveness and
ultimate load strength of tie-down arrangements. The commenters
asserted that offset methods for intermodal containers developed in the
1970s by some airlines had received Boeing support and approval.
We disagree with the request. The commenters did not submit data to
show how IATA OS 6/13 complies with the applicable regulations.
Further, IATA OS 6/13 documents procedures similar to those found to
have failed early on in the testing described in the preamble to the
NPRM. For example, these procedures include strapping the intermodal
container to the pallet, and not directly to the airplane. In fact, the
procedures described in IATA OS 6/13 are contrary to the Boeing Model
747 WBMs for the reasons discussed previously.
The commenters provided no evidence of Boeing support and approval
regarding use of offset methods. Boeing's comments did not include any
statement that offset carriage of intermodal containers without
restraint directly to the airplane complies with the Boeing Model 747
WBMs. Neither the FAA nor Boeing has found any evidence that Boeing was
involved in or aware of the carriage of intermodal containers in the
1970s.
We have not changed this final rule regarding this issue, although
any operator may request approval of an AMOC for use of an STC WBM
supplement. However, in this case, because IATA OS 6/13 is so similar
to the documented tested failures, new test data would be required to
show that the IATA method meets the applicable airworthiness
requirements to support approval of an STC.
Request To Allow Offset Containers, If Strapped to Airplane
Atlas Air, Boeing, AirbridgeCargo Airlines LLC (AirbridgeCargo),
NACA, and UPS requested that the intermodal containers be allowed to be
loaded offset on the pallet, provided that the containers are
restrained directly to the airplane by retention straps. A number of
the commenters stated that this practice is already allowed by the WBMs
and that they currently use this method.
We disagree with the request. None of the commenters provided any
actual data demonstrating a compliant restraint method to the airplane
for an offset intermodal container. Further, none have demonstrated
that they currently use a method complying with the Boeing WBMS. The
Boeing Model 747 WBMs describe how to restrain cargo, offset or not, as
special cargo restrained to the airplane; however, when the cargo is
restrained correctly to the airplane, so many straps would be attached
to so many locations on the aircraft that no cargo could be carried
adjacent to the offset intermodal container. Thus, the benefit of
increased capacity gained by installing an offset container would be
lost. Therefore, the FAA finds it unlikely that operators are actually
using compliant methods to restrain offset intermodal containers.
We have not changed this final rule regarding this issue. However,
under the provisions of paragraph (i) of this AD, we will consider
requests for approval of an AMOC if sufficient data are
[[Page 39948]]
submitted to substantiate that the alternative method would provide an
acceptable level of safety. These data would need to include the
compliant restraint methodology.
Request To Withdraw NPRM (79 FR 71037, December 1, 2014): Unlevel
Playing Field With International Carriers
Kalitta and the Michigan Senate requested that we withdraw the NPRM
(79 FR 71037, December 1, 2014). They asserted that by issuing this AD
we provide their foreign competitors with a significant competitive
advantage. Kalitta stated that while the FAA may believe that
incorporation of these restrictions into an AD will solve the
competition problem by ``leveling the playing field,'' as they will
apply to all U.S. carriers, and will be adopted by many foreign
governments, the agency needs to reconsider this position. The
commenters added that foreign authorities may or may not adopt the AD
as written, but they have wide latitude in what sort of AMOCs they will
permit their carriers to use. The commenters also stated that foreign
authorities will very likely look to the IATA standards to provide an
acceptable AMOC, enabling their carriers to continue to operate in the
very manner that will be foreclosed to U.S. air carriers.
Kalitta asserted that this ``unexpected gift to foreign airlines''
is not necessitated by safety of flight, and is contrary to the policy
considerations mandated by Congress in the International Air
Transportation Competition Act (49 U.S.C. 40101), which requires the
Secretary of Transportation to strengthen the competitive position of
air carriers to ensure at least equality with foreign air carriers,
including the attainment of the opportunity for air carriers to
maintain and increase their profitability in air foreign
transportation. According to the commenters, this obviously does not
mean that the FAA should ignore serious safety issues out of concern
for U.S. carriers' competitive position, but that the agency must take
account of U.S. carriers' financial health and competitive standing,
and avoid adopting measures and policies that harm carriers unless they
are absolutely necessary.
We disagree with the request. Section 44701 of 49 U.S.C. requires
the FAA to promote the safe flight of civil aircraft by, among other
things, prescribing regulations and minimum standards for aircraft. In
addition, the International Civil Aviation Organization (ICAO) Annex 8,
Airworthiness of Aircraft (<a href="http://www.icao.int/safety/airnavigation/NationalityMarks/annexes_booklet_en.pdf">http://www.icao.int/safety/airnavigation/NationalityMarks/annexes_booklet_en.pdf</a>) requires that civil aviation
authorities of other countries take appropriate action in response to
FAA ADs. Based on the FAA's determination of the unsafe condition
addressed by this AD, we expect foreign authorities to adopt similar
requirements. Regarding the potential for other civil aviation
authorities to adopt IATA's procedures as an AMOC for their ADs, as
discussed previously, the IATA procedures are similar to those that
have been tested previously and that the FAA considers to be unsafe. We
have no reason to believe other authorities would reach a different
conclusion.
We have not changed this final rule regarding this issue.
Request To Withdraw NPRM (79 FR 71037, December 1, 2014) or Delay
Issuance of AD Pending WBM Revision
NACA and AirbridgeCargo requested that we delay issuance of the AD
until all new testing is completed. Based on its understanding of the
current round of testing, NACA stated that there is a strong likelihood
the Boeing Model 747 WBMs will be revised. AirbridgeCargo proposed that
further research be done to establish a weight limit for intermodal
containers. The commenters therefore preferred a revised WBM to an AD,
which would also allow U.S. cargo carriers to fully compete with
foreign carriers on a level playing field.
We disagree with the request. To date, all testing to support a
revision to the Boeing Model 747 WBMs has been unsuccessful. Although
there is a current plan for more testing by a U.S. air carrier to
support an STC application, it is unclear if the testing will be
successful and when it will be completed. If the testing resumes and
provides a successful conclusion, and if sufficient data are submitted
to substantiate that the products or alternative methods would provide
an acceptable level of safety, the FAA could consider new methods or
products as acceptable for compliance with the requirements of this AD.
We have not changed this final rule regarding this issue.
Request To Change Requirement To Revise AFM
Boeing requested that we revise paragraph (g) of the proposed AD
(79 FR 71037, December 1, 2014), which proposed to require revising the
Operating Limitations section of the AFM. Boeing stated that airlines
are not able to revise a Boeing AFM. Boeing requested that we change
the requirement to ``insert a copy of this AD into the Limitations
section of the AFM.''
We disagree with the request. Paragraph (g) of the proposed AD (79
FR 71037, December 1, 2014) would allow operators to insert a copy of
this AD into the Limitations section of the AFM. However, operators may
also comply with this AD by revising the operating limitations.
Operating limitations are a part of the type certificate for an
airplane. For many years, we have imposed operating restrictions that
are necessary to address identified unsafe conditions by requiring
revisions to the Operating Limitations section of the AFM. For this
reason, as stated in the NPRM (79 FR 71037, December 1, 2014), we must
engage in rulemaking (i.e., issuance of an AD) in order to make the
revisions mandatory for previously type-certificated airplanes. While
the Boeing Model WBMs are contained in a ``Boeing document'' in the
sense that Boeing originally produced it, the document, nevertheless,
is a part of the airplane flight manual that operators must use to
operate the airplane properly. Of course, those operators that have
previously revised the required AFM limitations are given credit for
having previously accomplished the requirements of this AD, as allowed
by paragraph (f) of this AD. The legal effect is the same: The operator
is required to comply with the limitations referenced in 14 CFR
91.9(a). We have not changed this final rule regarding this issue.
Request To Revise Description of Issue Prompting Rulemaking
Boeing requested that we revise the description of the issue that
prompted the NPRM (79 FR 71037, December 1, 2014). The NPRM stated that
recent testing indicates that intermodal containers, when loaded as
cargo, can shift. While implicitly agreeing that loading offset
containers is unsafe unless they are restrained directly to the
airplane, Boeing requested that we change the wording to explain that
the condition is limited to ``cargo using a TSO-C90 certified ULD.''
We disagree with the requested change. The SUMMARY section of this
final rule and paragraph (e) of this AD go on to explain that
intermodal containers loaded in the offset method are the subject of
this AD, and the type of ULD does not change the unsafe condition.
Further, not all Boeing Model 747 WBMs refer to TSO-C90; several refer
directly to the TSO-C90-required document NAS 3610. We have therefore
not revised this final rule regarding this issue.
[[Page 39949]]
Request To Delete Reference to TSO Revision Level
Boeing and UPS stated that the SUPPLEMENTARY INFORMATION section of
the NPRM (79 FR 71037, December 1, 2014) referred to a ``TSO-C90D''
pallet. Revision D is the latest issue of TSO-C90, and per the WBMs
applicable to Boeing Model 747 airplanes, approved ULDs for carriage
may conform to the TSO-C90 revision to which they were certified. UPS
recommends revising the Discussion section of the NPRM to remove the
revision level when TSO-C90 is referenced.
We agree that the revision level of TSO-C90 does not matter; an
intermodal container conforms to none of the revision levels. However,
the Discussion section of the NPRM (79 FR 71037, December 1, 2014) is
not repeated in this final rule. No change to this final rule is
necessary.
Conclusion
We reviewed the relevant data, considered the comments received,
and determined that air safety and the public interest require adopting
this AD as proposed--except for minor editorial changes. We have
determined that these minor changes:
<bullet> Are consistent with the intent that was proposed in the
NPRM (79 FR 71037, December 1, 2014) for correcting the unsafe
condition; and
<bullet> Do not add any additional burden upon the public than was
already proposed in the NPRM (79 FR 71037, December 1, 2014).
Costs of Compliance
We estimate that this AD affects 98 airplanes of U.S. registry. We
estimate the following costs to comply with this AD:
Estimated Costs
----------------------------------------------------------------------------------------------------------------
Cost per Cost on U.S.
Action Labor cost Parts cost product operators
----------------------------------------------------------------------------------------------------------------
AFM revision...................... 1 work-hour x $85 per $0 $85 $8,330
hour = $85.
----------------------------------------------------------------------------------------------------------------
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):
2015-14-09 The Boeing Company: Amendment 39-18207; Docket No. FAA-
2014-0780; Directorate Identifier 2014-NM-168-AD.
(a) Effective Date
This AD is effective August 17, 2015.
(b) Affected ADs
None.
(c) Applicability
This AD applies to 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, 747SP, 747-8F, and 747-8 series airplanes,
certificated in any category, equipped with a main deck side cargo
door (MDSCD).
(d) Subject
Air Transport Association (ATA) of America Code 53, Fuselage.
(e) Unsafe Condition
This AD was prompted by recent testing that indicates that
intermodal containers, when loaded as cargo, under certain flight-
load conditions, can shift and impact the adjacent fuselage frames.
We are issuing this AD to prevent intermodal containers loaded in
the offset method from shifting during flight gust loads and
damaging fuselage frames, which could lead to the structural failure
of the aft fuselage in flight, and subsequent in-flight breakup of
the airplane.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Revision of Airplane Flight Manual (AFM)
Within 14 days after the effective date of this AD, revise the
Operating Limitations section of the FAA-approved AFM to include the
information in figure 1 to paragraph (g) of this AD. This may be
accomplished by inserting a copy of this AD into the Limitations
section of the AFM.
Figure 1 to Paragraph (g) of This AD--AFM Revision
------------------------------------------------------------------------
-------------------------------------------------------------------------
Unless approved by the Manager of the Seattle Aircraft Certification
Office, the carriage of the following payloads is prohibited:
[[Page 39950]]
(1) Intermodal containers nominally sized at 20 feet long, 8 feet wide,
and 8.5 feet tall that are not concentrically loaded on a pallet and
restrained to the aircraft in accordance with the FAA-approved Boeing
type certificate Weight and Balance Manual or a supplemental type
certificate Weight and Balance Supplement.
(2) ISO 668[dash]1CC containers that are not concentrically loaded on a
pallet and restrained to the aircraft in accordance with the FAA-
approved Boeing type certificate Weight and Balance Manual or a
supplemental type certificate Weight and Balance Supplement.
Note: Both payloads 1 and 2 may be concentrically loaded on a pallet and
netted in accordance with the FAA-approved Weight and Balance Manual
and then loaded in the center of the airplane and restrained to the
airplane by the approved center loaded cargo restraint system or
restrained directly to the airplane, both as defined in the FAA-
approved Weight and Balance Manual.
------------------------------------------------------------------------
(h) Special Flight Permits
Special flight permits, as described in Section 21.197 and
Section 21.199 of the Federal Aviation Regulations (14 CFR 21.197
and 21.199), are not allowed if any intermodal container prohibited
as specified in figure 1 to paragraph (g) of this AD is on board.
For special flight permits, carriage of freight is not allowed.
(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 paragraph (j) of this AD.
Information may be emailed to: <a href="/cdn-cgi/l/email-protection#f5ccd8b4bbb8d8a6909481819990d8b4b6bad8b4b8bab6d8a790848090868186b5939494db929a83"><span class="__cf_email__" data-cfemail="122b3f535c5f3f41777366667e773f53515d3f535f5d513f4077636777616661527473733c757d64">[email protected]</span></a>.
(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.
(j) Related Information
For more information about this AD, contact Steven C. Fox,
Senior Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle
Aircraft Certification Office (ACO), 1601 Lind Avenue SW., Renton,
WA 98057-3356; phone: 425-917-6425; fax: 425-917-6590; email:
<a href="/cdn-cgi/l/email-protection#d8abacbdaebdb6f6beb7a098beb9b9f6bfb7ae"><span class="__cf_email__" data-cfemail="e390978695868dcd858c9ba3858282cd848c95">[email protected]</span></a>.
(k) Material Incorporated by Reference
None.
Issued in Renton, Washington, on July 7, 2015.
Jeffrey E. Duven,
Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 2015-17031 Filed 7-10-15; 8:45 am]
BILLING CODE 4910-13-P
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