[Federal Register Volume 75, Number 3 (Wednesday, January 6, 2010)]
[Proposed Rules]
[Pages 793-801]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E9-31381]
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Proposed Rules
Federal Register
________________________________________________________________________
This section of the FEDERAL REGISTER contains notices to the public of
the proposed issuance of rules and regulations. The purpose of these
notices is to give interested persons an opportunity to participate in
the rule making prior to the adoption of the final rules.
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Federal Register / Vol. 75, No. 3 / Wednesday, January 6, 2010 /
Proposed Rules
[[Page 793]]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Parts 27 and 29
[Docket No. FAA-2009-0660; Notice No. 09-12]
RIN 2120-AJ52
Damage Tolerance and Fatigue Evaluation of Composite Rotorcraft
Structures
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: This proposal would revise airworthiness standards for type
certification requirements of normal and transport category rotorcraft.
The amendment would require evaluation of fatigue and residual static
strength of composite rotorcraft structures using a damage tolerance
evaluation, or a fatigue evaluation, if the applicant establishes that
a damage tolerance evaluation is impractical. The amendment would
address advances in composite structures technology and provide
internationally harmonized standards.
DATES: Send your comments on or before April 6, 2010
ADDRESSES: You may send comments identified by Docket Number FAA-2009-
0660 using any of the following methods:
Federal eRulemaking Portal: Go to http://www.regulations.gov and follow the online instructions for sending your
comments electronically.
Mail: Send comments to Docket Operations, M-30; U.S.
Department of Transportation, 1200 New Jersey Avenue, SE., Room W12-
140, West Building Ground Floor, Washington, DC 20590-0001.
Hand Delivery or Courier: Take comments to Docket
Operations in Room W12-140 of the West Building Ground Floor at 1200
New Jersey Avenue, SE., Washington, DC, between 9 a.m. and 5 p.m.,
Monday through Friday, except Federal holidays.
Fax: Fax comments to Docket Operations at 202-493-2251.
Privacy: We will post all comments we receive, without change, to
http://www.regulations.gov, including any personal information you
provide. Using the search function of our docket website, anyone can
find and read the electronic form of all comments received into any of
our dockets, including the name of the individual sending the comment
(or signing the comment for an association, business, labor union,
etc.). You may review DOT's complete Privacy Act Statement in the
Federal Register published on April 11, 2000 (65 FR 19477-78) or you
may visit http://DocketsInfo.dot.gov.
Docket: To read documents or comments received, go to http://www.regulations.gov and follow the online instructions for accessing
the docket. Or, go to Docket Operations in Room W12-140 of the West
Building Ground Floor at 1200 New Jersey Avenue, SE., Washington, DC,
between 9 a.m. and 5 p.m., Monday through Friday, except Federal
holidays.
FOR FURTHER INFORMATION CONTACT: For technical questions concerning
this proposed rule contact Sharon Y. Miles, Regulations and Policy
Group, Rotorcraft Directorate, ASW-111, Federal Aviation
Administration, 2601 Meacham Boulevard, Fort Worth, Texas 76137-0111;
telephone (817) 222-5122; facsimile (817) 222-5961; e-mail
[email protected]. For legal questions concerning this proposed
rule contact Steve C. Harold, Directorate Counsel, ASW-7G1, Federal
Aviation Administration, 2601 Meacham Boulevard, Fort Worth, Texas
76137-0007, telephone (817) 222-5099; facsimile (817) 222-5945, e-mail
[email protected].
SUPPLEMENTARY INFORMATION: Later in this preamble under the Additional
Information section, we discuss how you can comment on this proposal
and how we will handle your comments. Included in this discussion is
related information about the docket handling. We also discuss how you
can get a copy of related rulemaking documents.
Authority for This Rulemaking
The FAA's authority to issue rules on aviation safety is found in
Title 49 of the United States Code. 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.
This rulemaking is issued under the authority described in Subtitle
VII, Part A, Subpart III, Section 44701, ``General Requirements,''
Section 44702, ``Issuance of Certificates,'' and Section 44704, ``Type
Certificates, Production Certificates, and Airworthiness
Certificates.'' Under Section 44701, the FAA is charged with
prescribing regulations and minimum standards for practices, methods,
and procedures the Administrator finds necessary for safety in air
commerce. Under Section 44702, the Administrator may issue various
certificates including type certificates, production certificates, air
agency certificates, and airworthiness certificates. Under Section
44704, the Administrator must issue type certificates for aircraft,
aircraft engines, propellers, and specified appliances when the
Administrator finds the product is properly designed and manufactured,
performs properly, and meets the regulations and minimum standards
prescribed under section 44701(a). This regulation is within the scope
of these authorities because it would promote safety by updating the
existing minimum prescribed standards, used during the type
certification process, to address advances in composite structural
fatigue substantiation technology. It would also harmonize this
standard with international standards for evaluating the fatigue
strength of normal and transport category rotorcraft composite primary
structural elements.
Background and Statement of the Issues
The evolution of composite technology used in rotorcraft structures
is advancing rapidly. These rapid changes with the increased use of
composites in rotorcraft structures, issues discovered during
certification of composite structures, and service experiences of
composite rotorcraft structures over the last 25 years have caused us
to reconsider the current regulations and guidance materials for damage
tolerance and fatigue evaluation and to address the state of technology
in composite structures. The current certification process is based on
a broad interpretation of metallic fatigue
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substantiation and the design and construction airworthiness standards.
However, composite and metal structures are different. Composites are
complex materials that have unique advantages in fatigue strength,
weight, and tolerance to damage. The methodologies for evaluating
metallic structures are not necessarily suitable for composite
structures. Since composite structures differ from metallic structures,
the current regulations, Sec. Sec. 27.571 and 29.571, do not
adequately provide the fatigue certification requirements for composite
rotorcraft structures.
This may lead to inconsistent interpretations from one rotorcraft
certification project to another, resulting in different burdens on
industry to substantiate their composite rotorcraft structures. It has
also caused confusion for some certification applicants. These
applicants state there is no clear, complete guidance for certification
of composite rotorcraft structures.
To address these concerns, the FAA tasked the Aviation Rulemaking
Advisory Committee (ARAC) \1\ through its Composite Rotorcraft
Structure working group to provide advice and recommendations as
follows:
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\1\ Published in the Federal Register, April 5, 2000 (65 FR
17936).
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Recommend revisions to FAR/JAR 27 and 29 for composite
structures that are harmonized.
Evaluate and recommend, as appropriate, regulations,
advisory material, and related guidance to achieve the goal of improved
tolerance to flaws and defects in composite structure with methodology
and procedures that are practical and appropriate to rotorcraft.
This proposed rule is based on the ARAC's recommendations to the
FAA. The recommendations have been placed in the docket for this
rulemaking.
Related Activity
At the same time the ARAC was tasked with providing advice and
recommendations for composite rotorcraft structures, it was also tasked
with providing advice and recommendations for metallic rotorcraft
structures. Because of the unique characteristics and structural
capabilities of composite structures, we believe a separate rule is
needed for the damage tolerance and fatigue evaluations of rotorcraft
composite structures. In response to the ARAC recommendations for
improved standards for metallic structures, the FAA is developing an
NPRM entitled Fatigue Tolerance Evaluation of Metallic Structures.
General Discussion of Proposals
Composite structures present unique material behaviors and react
differently than metallic to damage and loading conditions. This
separate rulemaking action for the damage tolerance and fatigue
evaluation of composite structures is proposed to address the type
certification requirements for substantiating and certifying composite
rotorcraft structures including different aspects of the evaluation for
the most critical issues for each class of materials. These proposals
address the unique characteristics of composite materials and would
enable applicants to evaluate these types of materials in a different
manner from those of the traditional metallic materials.
The proposed changes would clarify the certification standards in
areas of frequent non-standardization and misinterpretation. These
proposals are intended to address fatigue damage tolerance conditions
that can reduce structural strength. In composites, low cycle fatigue
often yields minimal damage growth, whereas accidental damage from
impact can immediately reduce residual structural strength. Conversely,
in metals, any critical damage to the structure would be sensitive to
cyclic fatigue loads.
These proposals also address material and process variability and
environmental effects. The FAA proposes a strength requirement for
ultimate loads that would be applied when maximum acceptable
manufacturing defects and service damage are present. These proposals
would provide an exception to a damage tolerance evaluation if the
applicant establishes impracticability and, in that instance, would
allow a fatigue evaluation for some rotorcraft structures and damage
scenarios based on retirement times instead of inspection intervals
more commonly associated with damage tolerance standards. Under this
proposal, an applicant could demonstrate that certain damage would not
grow or does not grow beyond a certain threshold or size, and that the
damaged structure could still carry ultimate loads. In this instance,
an inspection may not be necessary and the structure could be assigned
a retirement life instead of a required inspection program. Further,
this proposal would require an applicant to conduct a threat
assessment, which is associated with the service history of composite
structures.
The proposals consider varying types of damage, loading conditions,
threat assessments, manufacturing defects, and residual strength
associated with composite structures. In developing these proposals, we
have recognized that it may be impractical within the limits of
geometry, inspectability, or good design practice to evaluate all the
composite structures of a rotorcraft using a damage tolerance
evaluation. Therefore, this proposal allows for a fatigue evaluation of
particular rotorcraft composite structures under Sec. Sec. 27.573(e)
and 29.573(e) where appropriate, instead of requiring a damage
tolerance evaluation for particular structures if the applicant can
establish that an impracticability exists. As part of the approval
process for fatigue evaluation of a particular rotorcraft composite
structure, the applicant would be required to identify the Principal
Structural Elements (PSEs) and the types of damage considered,
establish supplemental procedures to minimize the risk of catastrophic
failure associated with those types of damage, and include procedures
in the Airworthiness Limitation section of the Instructions for
Continued Airworthiness. The proposed requirements would minimize the
risk of catastrophic failure of composite structures used on rotorcraft
certificated in accordance with part 27 and part 29 standards.
Key Provisions in the New Rule
Some of the proposed requirements for evaluating composite
structures came from the current Sec. 29.571 standards. These
requirements in the evaluation process include certain steps, such as
identification of the PSEs, the in-flight measurements of loads, and
the use of loading spectra as severe as those expected in-service. This
proposal adds more detailed steps and does not refer to the current
flaw tolerant safe-life and fail-safe evaluations because there are
more suitable ways of describing each approach under damage tolerance.
Further, these proposals do not refer to the traditional safe-life
method because composites have sensitivities to defects and damage that
must be considered in design and certification testing that make the
traditional safe-life method inappropriate.
These proposals would revise the standards for determining
inspection intervals and retirement times based on results of damage
tolerance and fatigue evaluation. Currently, the minimum residual
structural strength requirement for any damage or defect that can be
found by inspection is tied to limit loads (maximum loads to be
expected in service). This proposal would link the required residual
structural strength to
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the probability of a given damage type, inspection interval, and damage
detectability. This link is necessary for at least two reasons. First,
one of the more critical threats--impact damage--could immediately
lower residual structural strength well below ultimate loads (limit
loads multiplied by prescribed factors of safety) if it occurs. The
proposal would ensure, as the residual structural strength is lowered,
the earlier damage would be detected and repaired. Inspections would be
required that would be frequent and comprehensive enough to reveal any
damage or defect growth to minimize the time that the rotorcraft might
be operated at less than an ultimate load capability. Second, this
proposal would address rare damage (such as a high-energy, blunt
impact) that is not detectable with the currently prescribed inspection
schemes issued for aircraft in operational service. Although such
damage may have a low probability of occurring, this proposal would
require that sufficient residual structural strength exists to
compensate for such damage.
These proposals would require that all PSEs, the failure of which
could result in catastrophic failure of the rotorcraft, meet ultimate
load residual structural strength requirements or require that a
retirement time be established if there could be any damage that may
not be found by a maintenance inspection. Under this proposal, an
applicant would establish a retirement time to assess the damage that
may not be found by inspection or to eliminate the burden of the
repeated inspections by the rotorcraft owners. For damage detectable by
inspection, the proposal would establish a limit load requirement to
repair and restore the structure to its ultimate strength capability.
The FAA proposes to include all PSE assessments for damage threats,
residual strength and fatigue characteristics to the list of
requirements for inspection intervals or replacement times as stated in
proposed Sec. Sec. 27.573(d)(1) and 29.573(d)(1). As a minimum, the
fatigue evaluation would include the PSEs of the:
--Airframe,
--Main and tail rotor drive systems,
--Main and tail rotor blades and hubs,
--Rotor controls,
--Fixed and movable control surfaces,
--Engine and transmission mountings (provided by the airframe
manufacturer), and
--Landing gear and other parts; as well as performing damage tolerance
evaluations of the strength of composite:
--Detail design points and
--Fabrication techniques considered critical by the FAA to avoid
catastrophic failure due to static or fatigue loads.
The proposal would require consideration of the effects of fatigue
damage on stiffness, dynamic behavior, loads, and functional
performance of composite structures. In the existing rule, such
requirements are limited to fail-safe evaluations. These
characteristics are not considered to be a serious threat to residual
structural strength.
The FAA recognizes there may be limited cases in which a damage
tolerance evaluation may be impractical. In these rare cases, the
applicant would be required to identify the nature of the evaluation
and provide a justification to the FAA for the determination of its
impracticality. The justification would support the specific types of
damage to the PSE that would qualify for a fatigue evaluation. Finally,
the proposal would require the applicant to establish replacement
times, structural inspection intervals, and related structural
inspection procedures to minimize the risk of catastrophic failure
because of such damage. The required replacement times, inspection
intervals, and structural inspections would be included in the
Instructions for Continued Airworthiness as required by Sec. Sec.
27.1529 and 29.1529.
Additionally, the FAA recognizes that rare types of damage, such as
high-energy, blunt impacts may not be uncovered as part of a base field
inspection during scheduled maintenance inspection intervals. This
proposal would require that the applicant substantiate sufficient
residual structural strength to maintain an adequate level of safety in
the event of an occurrence of rare damage. Supplemental procedures may
be required to adequately address rare impact damage.
Airworthiness Limitations Section (Appendix A to Parts 27 and 29)
This proposal would require the mandatory replacement times,
structural inspection intervals, and related structural inspection
procedures produced under the requirements of Sec. Sec. 27.571 and
29.571, the new Sec. Sec. 27.573 and 29.573, and any other similar
requirement for type certification be included in the Airworthiness
Limitations Section of the Instructions for Continued Airworthiness.
Paperwork Reduction Act
This proposal contains the following new information collection
requirements. As required by 44 U.S.C. 3507(d) of the Paperwork
Reduction Act of 1995, as implemented by 5 CFR part 1320, the FAA has
submitted the information requirements associated with this proposal to
the Office of Management and Budget (OMB) for review.
Title: Damage Tolerance and Fatigue Evaluation of Composite
Rotorcraft Structures.
Summary: This proposal would add new certification standards for
normal and transport category rotorcraft to address advances in
structural damage tolerance and fatigue substantiation technology for
composite rotorcraft structures. These proposals would increase the
current minimum safety standards to require compliance with certain
current industry practices and FAA policies that would result in higher
safety standards, and would result in harmonized international
standards. These proposals would help ensure that if damage occurs to
composite structures during manufacturing or within the operational
life of the rotorcraft, the remaining structure could withstand fatigue
loads that are likely to occur, without failure, until the damage is
detected. The damaged structure must then be repaired to restore
ultimate load capability, or the part must be replaced. Proposed
Sec. Sec. 27.573 and 29.573 would require that applicants get FAA
approval of their proposed methods for complying with the certification
requirements for damage tolerance and fatigue evaluation of composite
structures.
Use of information: The required damage tolerance and fatigue
evaluation information would be determined for principal composite
structural elements or components, detail design points, and
fabrication techniques and would be collected from rotorcraft
certification applicants. The FAA would use the approval process for
the Applicant's submitted compliance methodology to determine whether
the proposed methods were sufficient to comply with the certification
requirements for damage tolerance and fatigue evaluation of composite
structures. The FAA also would use the approval process for the
Applicant's submitted compliance methodology to determine if the
rotorcraft has any unsafe features in the composite structures.
Respondents: The likely respondents to this proposed damage
tolerance and fatigue evaluation information are applicants requesting
type certification of composite structures. We anticipate about 10
normal and transport category rotorcraft certification applicants
(including supplemental type certificate
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applicants) over the 27-year analysis period or about 0.4 per year.
Frequency: The frequency of determining the damage tolerance and
fatigue evaluation methodologies would depend on how often an applicant
seeks certification of a composite structure. This compliance
methodology would be provided during each certification. We anticipate
16.5 certifications over the 27 year analysis period or about 0.6 per
year.
Annual Burden Estimate: The compliance methodology would be
required to be submitted and approved during each certification of a
composite rotorcraft structure. We anticipate there would be 0.6
certifications each year and it would take 182 hours to submit and
approve the compliance methodology for each certification, for a total
annual time burden of 109 hours. We anticipate that submitting and
approving the compliance methodology for each certification would cost
$100.00 per hour. Therefore, the estimated total annual cost burden
would be $10,900.00.
The agency is asking for comments to--
(1) evaluate whether the proposed information requirement is
necessary for the proper performance of the functions of the agency,
including whether the information will have practical utility;
(2) evaluate the accuracy of the agency's estimate of the burden;
(3) improve the quality, utility, and clarity of the information to
be collected; and
(4) minimize the burden of collecting information on those who are
to respond, by using appropriate automated, electronic, mechanical, or
other technological collection techniques or other forms of information
technology.
Individuals and organizations may submit comments on the
information collection requirement by March 8, 2010, and should direct
them to the address listed in the ADDRESSES section. Comments also
should be submitted to the Office of Management and Budget, Office of
Information and Regulatory Affairs, Attention: Desk Officer for FAA,
New Executive Building, Room 10202, 725 17th Street, NW., Washington,
DC 20053.
According to the 1995 amendments to the Paperwork Reduction Act and
5 CFR 1320.8(b)(3)(vi), an agency may not collect or sponsor the
collection of information, nor may it impose an information collection
requirement unless it displays a currently valid OMB control number.
The OMB control number for this information collection will be
published in the Federal Register, after the Office of Management and
Budget approval.
International Compatibility
In keeping with U.S. obligations under the Convention on
International Civil Aviation, it is FAA's policy to comply with
International Civil Aviation Organization (ICAO) Standards to the
maximum extent practicable. The FAA has determined that the proposed
rule is consistent with the ICAO standard in ICAO Annex 8, Part IV.
European Aviation Safety Agency
The European Aviation Safety Agency (EASA) was established by the
European Community to develop standards to ensure safety and
environmental protection, oversee uniform application of those
standards, and promote them internationally. EASA formally became
responsible for certification of aircraft, engines, parts, and
appliances on September 28, 2003. The FAA and EASA are coordinating
their rulemaking efforts to facilitate harmonized standards for
evaluating the fatigue strength of composite rotorcraft structures.
Regulatory Evaluation, Regulatory Flexibility Determination,
International Trade Impact Assessment, and Unfunded Mandates Assessment
Changes to Federal regulations must undergo several economic
analyses. First, Executive Order 12866 directs that each Federal agency
shall propose or adopt a regulation only upon a reasoned determination
that the benefits of the intended regulation justify its costs. Second,
the Regulatory Flexibility Act of 1980 (Public Law 96-354) requires
agencies to analyze the economic impact of regulatory changes on small
entities. Third, the Trade Agreements Act (Pub. L. 96-39) prohibits
agencies from setting standards that create unnecessary obstacles to
the foreign commerce of the United States. In developing U.S.
standards, this Trade Act requires agencies to consider international
standards and, where appropriate, that they be the basis of U.S.
standards. Fourth, the Unfunded Mandates Reform Act of 1995 (Pub. L.
104-4) requires agencies to prepare a written assessment of the costs,
benefits, and other effects of proposed or final rules that include a
Federal mandate likely to result in the expenditure by State, local, or
tribal governments, in the aggregate, or by the private sector, of $100
million or more annually (adjusted for inflation with base year of
1995). This portion of the preamble summarizes the FAA's analysis of
the economic impacts of this proposed rule. We suggest readers seeking
greater detail read the full regulatory evaluation, a copy of which we
have placed in the docket for this rulemaking.
In conducting these analyses, the FAA has determined that this
proposed rule:
(1) Has benefits that justify its costs;
(2) Is not an economically ``significant regulatory action'' as
defined in section 3(f) of Executive Order 12866;
(3) Has been determined by the Office of Management and Budget to
be a ``non-significant regulatory action;''
(4) Is not ``significant'' as defined in DOT's Regulatory Policies
and Procedures;
(5) Would not have a significant economic impact on a substantial
number of small entities;
(6) Would not have a significant effect on international trade; and
(7) Would not impose an unfunded mandate on State, local, or tribal
governments by exceeding the monetary threshold identified.
These analyses are summarized below.
Total Benefits and Costs of This Rulemaking
The estimated total cost of this proposed rule is about $713,000
($392,000 in present value, discounted at 7% for 27 years).
Who is Potentially Affected by this Rulemaking?
Manufacturers of U.S.-registered part 27 and part 29
rotorcraft, and
Operators of part 27 and part 29 rotorcraft.
Our Cost Assumptions and Sources of Information.
Discount rate--7%
Period of analysis of 27 years equals the 27 years of
National Transportation Safety Board accident history. During this
period, manufacturers will seek new certifications for 10.5 part 27
rotorcraft and six part 29 rotorcraft.
This proposed rule consolidates FAA and industry past activities
including special conditions, advisory circulars, and industry practice
regarding the use of composites on rotorcraft. The benefits of this
action exceed the small costs of this proposed rule.
We estimate the costs of this proposed rule to be about $713,000
($392,000 in present value) over the 27-year analysis period.
Manufacturers of 14 CFR part 27 rotorcraft would incur costs of
$101,000 ($55,000 in present value) and manufacturers of 14 CFR part 29
helicopters would incur costs of $612,000 ($337,000 in present value).
Regulatory Flexibility Determination
The Regulatory Flexibility Act of 1980 (RFA) establishes ``as a
principle of
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regulatory issuance that agencies shall endeavor, consistent with the
objective of the rule and of applicable statutes, to fit regulatory and
informational requirements to the scale of the business, organizations,
and governmental jurisdictions subject to regulation.'' To observe that
principle, the RFA requires agencies to solicit and consider flexible
regulatory proposals and to explain the rationale for their actions.
The RFA covers a wide-range of small entities, including small
businesses, not-for-profit organizations and small governmental
jurisdictions.
Agencies must perform a review to determine whether a proposed or
final rule will have a significant economic impact on a substantial
number of small entities. If the agency determines that it will, the
agency must prepare a regulatory flexibility analysis as described in
the Act.
If an agency determines that a proposed or final rule is not
expected to have a significant economic impact on a substantial number
of small entities, section 605(b) of the 1980 RFA provides that the
head of the agency may so certify, and a regulatory flexibility
analysis is not required. The certification must include a statement
providing the factual basis for this determination, and the reasoning
should be clear.
This proposed rule would affect rotorcraft manufacturers and
rotorcraft operators. Therefore, the effect on potential small entities
is analyzed separately for helicopter manufacturers and operators.
Part 27 Helicopter Manufacturers
Size Standards
Size standards for small entities are published by the Small
Business Administration (SBA) on their Web site at http://www.sba.gov/size. The size standards used herein are from ``SBA U.S. Small Business
Administration, Table of Small Business Size Standards, Matched to
North American Industry Classification System Codes.'' The table is
effective August 22, 2008 and uses the 2007 NAICS codes.
Helicopter manufacturers are listed in the above-referenced table
under Sector 31-33--Manufacturing; Subsector 336--Transportation
Equipment Manufacturing; NAICS Code 336411--Aircraft Manufacturing. The
small entity size standard is 1,500 employees.
Table R1 shows there are six U.S. part 27 helicopter manufacturers
that produce composite helicopters. MD Helicopters, with 400 employees,
is the only part 27 helicopter manufacturer to qualify as a small
entity. It is estimated that MD Helicopters has annual revenues of
$175,000,000. The cost of this rule for one part 27 helicopter
certification for a part 27 manufacturer is estimated to be $9,600 over
27 years, and the total number of such certifications is estimated at
10.5, if only one of these were performed by MD Helicopters, the cost
would be equivalent to 0.005 percent of their total revenue, which
would not represent a significant cost. Therefore, it is not
anticipated that this proposed rule would have a significant economic
impact on a substantial number of part 27 helicopter manufacturers.
Table R1--U.S. Part 27 Helicopter Manufacturers
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Manufacturer Annual
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Proposal
Number Name Ultimate owner Employees Small entity Revenues (AR) costs (PC) % PC of AR
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1............................... Agusta (A)......... Finmeccanica...... 73,000 No................ [euro]15,037,000 N.A. N.A.
2............................... Bell Helicopter (B) Textron........... 42,000 No................ $14,200,000,000 N.A. N.A.
3............................... Eurocopter (C)..... EADS.............. 118,000 No................ [euro]43,3000,000, N.A. N.A.
000
4............................... Kaman Aerospace (D) Kaman Corp........ 4,000 No................ $1,200,000,000 N.A. N.A.
5............................... MD Helicopters None.............. 400 Yes............... $175,000,000 $9,600 0.01%
(E)(F).
6............................... Sikorsky (G)....... UTC............... 223,100 No................ $58,700,000,000 N.A. N.A.
7............................... Robinson .................. ........... .................. .................. ........... ...........
Helicopters (H).
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Notes:
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(A) http://www.finmeccanica.com
(B) http://www.Textron.com/about/company
(C) http://www.eads.com
(D) http://www.kaman.com
(E) http://www.linkdin.com
(F) http://www.jigsaw.com/id55718/md_helicopters_company.xhtml (Average of range of $100-$250 million) Cost is based on one helicopter certifcation
during the analysis period.
(G) http://www.utc.com/about_utc/fast_facts.Ihtml
(H) Robinson Helicopters is not included because it produces only metallic helicopters and is not expected to produce composite heliopters in the
future..
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8/10/2009
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Part 29 Helicopter Manufacturers
Size Standards
Size standards for part 29 manufacturers are the same as the size
standards for part 27 manufacturers.
Table R2 shows there are four U.S. part 29 helicopter manufacturers
currently producing helicopters. None of these manufacturers qualifies
as a small entity. Therefore, it is not anticipated that this proposed
rule would have a significant economic impact on a substantial number
of part 29 helicopter manufacturers.
[[Page 798]]
Table R1--U.S. Part 29 Helicopter Manufacturers
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Manufacturer Annual
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Proposal
Number Name Ultimate owner Employees Small entity Revenues (AR) costs (PC) % PC of AR
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1............................... Agusta (A)......... Finmeccanica...... 73,000 No................ [euro]15,037,000 N.A. N.A.
2............................... Bell Helicopter (B) Textron........... 42,000 No................ $14,200,000,000 N.A. N.A.
3............................... Eurocopter (C)..... EADS.............. 118,000 No................ [euro]43,3000,000, N.A. N.A.
000
4............................... Sikorsky (F)....... UTC............... 223,100 No................ $58,700,000,000 N.A. N.A.
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Notes:
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(A) http://www.finmeccanica.com
(B) http://www.Textron.com/about/company
(C) http://www.eads.com
(F) http://www.utc.com/about_utc/fast_facts.lhtml
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8/10/2009
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Part 27 and Part 29 Helicopter Operators
Size Standards
While there are only seven part 27 and four part 29 helicopter
manufacturers in the United States, there are many small entities that
are operators of part 27 and part 29 helicopters. Each of these
operators may provide many services or only one. Such services include
offshore transportation, executive transportation, fire-fighting,
Emergency Medical Services (EMS), and training in maintenance, repair,
and modification.
The SBA lists small entity size standards for air transportation
under Sector 44-45, Retail Trade, Subsector 481, Air Transportation.
The small entity size standards are 1,500 employees for scheduled and
nonscheduled charter passenger and freight transportation. This
standard is $28.0 million annually if the passenger or freight air
transportation is offshore marine air transportation. Finally, the
small entity size standard for other--non-scheduled air transportation
is $7.0 million annually.
This proposed rule is not expected to increase the costs of part 27
or part 29 helicopter operators, because we believe the helicopter
inspection time for a composite part will be the same as or less than
for a metallic part inspection. We request comments regarding this
assumption.
Consequently, the FAA certifies that this proposed rule would not
have a significant economic impact on a substantial number of part 27
or part 29 rotorcraft manufacturers or operators.
International Trade Impact Assessment
The Trade Agreements Act of 1979 (Pub. L. 96-39), as amended by the
Uruguay Round Agreements Act (Pub. L. 103-465), prohibits Federal
agencies from establishing standards or engaging in related activities
that create unnecessary obstacles to the foreign commerce of the United
States. Pursuant to these Acts, establishing standards is not
considered an unnecessary obstacle to the foreign commerce of the
United States, so long as the standard has a legitimate domestic
objective, such as the protection of safety, and does not operate in a
manner that excludes imports that meet this objective. The statute also
requires consideration of international standards and, where
appropriate, that they be the basis for U.S. standards. The FAA has
assessed the potential effect of this proposed rule and determined that
it would impose the same costs on domestic and international entities
and thus has a neutral trade impact.
Unfunded Mandates Assessment
Title II of the Unfunded Mandates Reform Act of 1995 (Pub. L. 104-
4) requires each Federal agency to prepare a written statement
assessing the effects of any Federal mandate in a proposed or final
agency rule that may result in an expenditure of $100 million or more
(adjusted annually for inflation) in any 1 year by state, local, and
tribal governments, in the aggregate, or by the private sector; such a
mandate is deemed to be a ``significant regulatory action.'' The FAA
currently uses an inflation-adjusted threshold value of $141.3 million.
This proposed rule does not contain such a mandate.
Executive Order 13132, Federalism
The FAA has analyzed this proposed rule under the principles and
criteria of Executive Order 13132, Federalism. We determined that this
action 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, and therefore, would not have federalism implications.
Regulations Affecting Intrastate Aviation in Alaska
Section 1205 of the FAA Reauthorization Act of 1996 (110 Stat.
3213) requires the Administrator, when modifying regulations in Title
14 of the CFR in a manner affecting intrastate aviation in Alaska, to
consider the extent to which Alaska is not served by transportation
modes other than aviation, and to establish appropriate regulatory
distinctions. Because this proposed rule would apply to the
certification of future designs of rotorcraft and their subsequent
operation, it could, if adopted, affect intrastate aviation in Alaska.
The FAA, therefore, specifically requests comments on whether there is
justification for applying the proposed rule differently in intrastate
operations in Alaska.
Environmental Analysis
FAA Order 1050.1E identifies FAA actions that are categorically
excluded from preparation of an environmental assessment or
environmental impact statement under the National Environmental Policy
Act in the absence of extraordinary circumstances. The FAA has
determined this proposed rulemaking action qualifies for the
categorical exclusion identified in paragraph 312f and involves no
extraordinary circumstances.
Regulations That Significantly Affect Energy Supply, Distribution, or
Use
The FAA has analyzed this NPRM under Executive Order 13211, Actions
Concerning Regulations that Significantly Affect Energy Supply,
[[Page 799]]
Distribution, or Use (May 18, 2001). We have determined that it is not
a ``significant regulatory action'' under the executive order because
it is not likely to have a significant adverse effect on the supply,
distribution, or use of energy.
Additional Information
Comments Invited:
The FAA invites interested persons to participate in this
rulemaking by submitting written comments, data, or views. We also
invite comments relating to the economic, environmental, energy, or
federalism impacts that might result from adopting the proposals in
this document. The most helpful comments reference a specific portion
of the proposal, explain the reason for any recommended change, and
include supporting data. To ensure the docket does not contain
duplicate comments, please send only one copy of written comments, or
if you are filing comments electronically, please submit your comments
only one time.
We will file in the docket all comments we receive, as well as a
report summarizing each substantive public contact with FAA personnel
concerning this proposed rulemaking. Before acting on this proposal, we
will consider all comments we receive on or before the closing date for
comments. We will consider comments filed after the comment period has
closed if it is possible to do so without incurring expense or delay.
We may change this proposal in light of the comments we receive.
Availability of Rulemaking Documents
You can get an electronic copy of rulemaking documents using the
Internet by--
1. Searching the Federal eRulemaking Portal (http://www.regulations.gov);
2. Visiting the FAA's Regulations and Policies Web page at http://www.faa.gov/regulations_policies/; or
3. Accessing the Government Printing Office's Web page at http://www.gpoaccess.gov/fr/index.html.
You can also get a copy by sending a request to the Federal
Aviation Administration, Office of Rulemaking, ARM-1, 800 Independence
Avenue, SW., Washington, DC 20591, or by calling (202) 267-9680. Make
sure to identify the docket number, notice number, or amendment number
of this rulemaking.
You may access all documents the FAA considered in developing this
proposed rule, including economic analyses and technical reports, from
the internet through the Federal eRulemaking Portal referenced in
paragraph 1.
List of Subjects
14 CFR Part 27
Aircraft, Aviation safety.
14 CFR Part 29
Aircraft, Aviation safety.
The Proposed Amendment
In consideration of the foregoing, the Federal Aviation
Administration proposes to amend parts 27 and 29 of Title 14, Code of
Federal Regulations, as follows:
PART 27--AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT
1. The authority citation for part 27 continues to read as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701-44702, 44704.
2. Add a new Sec. 27.573 to read as follows:
Sec. 27.573 Damage Tolerance and Fatigue Evaluation of Composite
Rotorcraft Structures.
(a) Each applicant must evaluate the composite rotorcraft structure
under the damage tolerance standards of paragraph (d) of this section
unless the applicant establishes that a damage tolerance evaluation is
impractical within the limits of geometry, inspectability, and good
design practice. If an applicant establishes that it is impractical
within the limits of geometry, inspectability, and good design
practice, the applicant must do a fatigue evaluation in accordance with
paragraph (e) of this section.
(b) The compliance methodology of each applicant, and the results
of that methodology, requires FAA approval.
(c) Definitions:
(1) Catastrophic failure is an event that could prevent continued
safe flight and landing.
(2) Principal Structural Elements (PSEs) are structural elements
that contribute significantly to the carrying of flight or ground
loads, the failure of which could result in catastrophic failure of the
rotorcraft.
(3) Threat Assessment is an assessment that specifies the
locations, types, and sizes of damage, considering fatigue,
environmental effects, intrinsic and discrete flaws, and impact or
other accidental damage (including the discrete source of the
accidental damage) that may occur during manufacture or operation.
(d) Damage Tolerance Evaluation:
(1) Each applicant must show that catastrophic failure due to
static and fatigue loads, considering the intrinsic or discrete
manufacturing defects or accidental damage, is avoided throughout the
operational life or prescribed inspection intervals of the rotorcraft
by performing damage tolerance evaluations of the strength of composite
PSEs and other parts, detail design points, and fabrication techniques.
Each applicant must account for the effects of material and process
variability along with environmental conditions in the strength and
fatigue evaluations. Each applicant must evaluate parts that include
PSEs of the airframe, main and tail rotor drive systems, main and tail
rotor blades and hubs, rotor controls, fixed and movable control
surfaces, engine and transmission mountings, landing gear and other
parts, detail design points, and fabrication techniques deemed critical
by the FAA. Each damage tolerance evaluation must include:
(i) The identification of all PSEs;
(ii) In-flight and ground measurements for determining the loads or
stresses for all PSEs for all critical conditions throughout the range
of limits in Sec. 27.309 (including altitude effects), except that
maneuvering load factors need not exceed the maximum values expected in
service;
(iii) The loading spectra as severe as those expected in service
based on loads or stresses determined under paragraph (d)(1)(ii) of
this section, including external load operations, if applicable, and
other operations including high-torque events;
(iv) A threat assessment for all PSEs that specifies the locations,
types, and sizes of damage, considering fatigue, environmental effects,
intrinsic and discrete flaws, and impact or other accidental damage
(including the discrete source of the accidental damage) that may occur
during manufacture or operation; and
(v) An assessment of the residual strength and fatigue
characteristics of all PSEs that supports the replacement times and
inspection intervals established under paragraph (d)(2) of this
section.
(2) Each applicant must establish replacement times, inspections,
or other procedures for all PSEs to require the repair or replacement
of damaged parts before a catastrophic failure. These replacement
times, inspections, or other procedures must be included in the
Airworthiness Limitations Section of the Instructions for Continued
Airworthiness required by Sec. 27.1529.
(i) Replacement times for PSEs must be determined by tests, or by
analysis supported by tests, and must show that
[[Page 800]]
the structure is able to withstand the repeated loads of variable
magnitude expected in-service. In establishing these replacement times,
the following items must be considered:
(A) Damage identified in the threat assessment required by
paragraph (d)(1)(iv) of this section;
(B) Maximum acceptable manufacturing defects and in-service damage
(i.e., those that do not lower the residual strength below ultimate
design loads and those that can be repaired to restore ultimate
strength); and
(C) Ultimate load strength capability after applying repeated
loads.
(ii) Inspection intervals for PSEs must be established to reveal
any damage identified in the threat assessment required by paragraph
(d)(1)(iv) of this section that may occur from fatigue or other in-
service causes before such damage has grown to the extent that the
component cannot sustain the required residual strength capability. In
establishing these inspection intervals, the following items must be
considered:
(A) The growth rate, including no-growth, of the damage under the
repeated loads expected in-service determined by tests or analysis
supported by tests;
(B) The required residual strength for the assumed damage
established after considering the damage type, inspection interval,
detectability of damage, and the techniques adopted for damage
detection. The minimum required residual strength is limit load; and
(C) Whether the inspection will detect the damage growth before the
minimum residual strength is reached and restored to ultimate load
capability, or whether the component will require replacement.
(3) Each applicant must consider the effects of damage on
stiffness, dynamic behavior, loads, and functional performance on all
PSEs in establishing the allowable damage size and inspection interval.
(e) Fatigue Evaluation: If an applicant establishes that the damage
tolerance evaluation described in paragraph (d) of this section is
impractical within the limits of geometry, inspectability, or good
design practice, the applicant must do a fatigue evaluation of the
particular composite rotorcraft structure and:
(1) Identify all PSEs considered in the fatigue evaluation;
(2) Identify the types of damage for all PSEs considered in the
fatigue evaluation;
(3) Establish supplemental procedures to minimize the risk of
catastrophic failure associated with the damages identified in
paragraph (e) of this section; and
(4) Include these supplemental procedures in the Airworthiness
Limitations section of the Instructions for Continued Airworthiness
required by Sec. 27.1529.
Appendix A to Part 27 [Amended]
3. Amend the second sentence of section A.27.4 of Appendix A to
Part 27 by removing the phrase ``approved under Sec. 27.571'' and
adding the phrase ``required for type certification'' in its place.
PART 29--AIRWORTHINESS STANDARDS: TRANSPORT CATEGORY ROTORCRAFT
4. The authority citation for part 29 continues to read as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701-44702, 44704.
5. Add a new Sec. 29.573 to read as follows:
Sec. 29.573 Damage Tolerance and Fatigue Evaluation of Composite
Rotorcraft Structures.
(a) Each applicant must evaluate the composite rotorcraft structure
under the damage tolerance standards of paragraphs (d) of this section
unless the applicant establishes that a damage tolerance evaluation is
impractical within the limits of geometry, inspectability, and good
design practice. If an applicant establishes that it is impractical
within the limits of geometry, inspectability, and good design
practice, the applicant must do a fatigue evaluation in accordance with
paragraph (e) of this section.
(b) The compliance methodology of each applicant, and the results
of that methodology, requires approval by the FAA.
(c) Definitions:
(1) Catastrophic failure is an event that could prevent continued
safe flight and landing.
(2) Principal Structural Elements (PSEs) are structural elements
that contribute significantly to the carrying of flight or ground
loads, the failure of which could result in catastrophic failure of the
rotorcraft.
(3) Threat Assessment is an assessment that specifies the
locations, types, and sizes of damage, considering fatigue,
environmental effects, intrinsic and discrete flaws, and impact or
other accidental damage (including the discrete source of the
accidental damage) that may occur during manufacture or operation.
(d) Damage Tolerance Evaluation:
(1) Each applicant must show that catastrophic failure due to
static and fatigue loads, considering the intrinsic or discrete
manufacturing defects or accidental damage, is avoided throughout the
operational life or prescribed inspection intervals of the rotorcraft
by performing damage tolerance evaluations of the strength of composite
PSEs and other parts, detail design points, and fabrication techniques.
Each applicant must account for the effects of material and process
variability along with environmental conditions in the strength and
fatigue evaluations. Each applicant must evaluate parts that include
PSEs of the airframe, main and tail rotor drive systems, main and tail
rotor blades and hubs, rotor controls, fixed and movable control
surfaces, engine and transmission mountings, landing gear and other
parts, detail design points, and fabrication techniques deemed critical
by the FAA. Each damage tolerance evaluation must include:
(i) The identification of all PSEs;
(ii) In-flight and ground measurements for determining the loads or
stresses for all PSEs for all critical conditions throughout the range
of limits in Sec. 29.309 (including altitude effects), except that
maneuvering load factors need not exceed the maximum values expected in
service;
(iii) The loading spectra as severe as those expected in service
based on loads or stresses determined under paragraph (d)(1)(ii) of
this section, including external load operations, if applicable, and
other operations including high-torque events;
(iv) A threat assessment for all PSEs that specifies the locations,
types, and sizes of damage, considering fatigue, environmental effects,
intrinsic and discrete flaws, and impact or other accidental damage
(including the discrete source of the accidental damage) that may occur
during manufacture or operation; and
(v) An assessment of the residual strength and fatigue
characteristics of all PSEs that supports the replacement times and
inspection intervals established under paragraph (d)(2) of this
section.
(2) Each applicant must establish replacement times, inspections,
or other procedures for all PSEs to require the repair or replacement
of damaged parts before a catastrophic failure. These replacement
times, inspections, or other procedures must be included in the
Airworthiness Limitations Section of the Instructions for Continued
Airworthiness required by Sec. 29.1529.
(i) Replacement times for PSEs must be determined by tests, or by
analysis supported by tests, and must show that the structure is able
to withstand the repeated loads of variable magnitude expected in-
service. In establishing
[[Page 801]]
these replacement times, the following items must be considered:
(A) Damage identified in the threat assessment required by
paragraph (d)(1)(iv) of this section;
(B) Maximum acceptable manufacturing defects and in-service damage
(i.e., those that do not lower the residual strength below ultimate
design loads and those that can be repaired to restore ultimate
strength); and
(C) Ultimate load strength capability after applying repeated
loads.
(ii) Inspection intervals for PSEs must be established to reveal
any damage identified in the threat assessment required by paragraph
(d)(1)(iv) of this section that may occur from fatigue or other in-
service causes before such damage has grown to the extent that the
component cannot sustain the required residual strength capability. In
establishing these inspection intervals, the following items must be
considered:
(A) The growth rate, including no-growth, of the damage under the
repeated loads expected in-service determined by tests or analysis
supported by tests;
(B) The required residual strength for the assumed damage
established after considering the damage type, inspection interval,
detectability of damage, and the techniques adopted for damage
detection. The minimum required residual strength is limit load; and
(C) Whether the inspection will detect the damage growth before the
minimum residual strength is reached and restored to ultimate load
capability, or whether the component will require replacement.
(3) Each applicant must consider the effects of damage on
stiffness, dynamic behavior, loads, and functional performance on all
PSEs in establishing the allowable damage size and inspection interval.
(e) Fatigue Evaluation: If an applicant establishes that the damage
tolerance evaluation described in paragraph (d) of this section is
impractical within the limits of geometry, inspectability, or good
design practice, the applicant must do a fatigue evaluation of the
particular composite rotorcraft structure and:
(1) Identify all PSEs considered in the fatigue evaluation;
(2) Identify the types of damage for all PSEs considered in the
fatigue evaluation;
(3) Establish supplemental procedures to minimize the risk of
catastrophic failure associated with the damages identified in
paragraph (e) of this section; and
(4) Include these supplemental procedures in the Airworthiness
Limitations section of the Instructions for Continued Airworthiness
required by Sec. 29.1529.
Appendix A to Part 29 [Amended]
6. Amend the second sentence of section A.29.4 of Appendix A to
Part 29 by removing the phrase ``approved under Sec. 29.571'' and
adding the phrase ``required for type certification'' in its place.
Issued in Washington, DC, on December 18, 2009.
K.C. Yanamura,
Acting Director, Aircraft Certification Service.
[FR Doc. E9-31381 Filed 1-5-10; 8:45 am]
BILLING CODE 4910-13-P