Document ID: FAA-2011-0629-0001
Agency: faa
Document Type: Proposed Rule
Title: Noise Certification Standards for Tiltrotors
Posted Date: 2011-06-21T04:00Z

[Federal Register Volume 76, Number 119 (Tuesday, June 21, 2011)]
[Proposed Rules]
[Pages 36001-36011]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-15276]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Parts 21 and 36

[Docket No. FAA-2011-0629; Notice No. 11-04 ]
RIN 2120-AJ76

Noise Certification Standards for Tiltrotors

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This rulemaking would establish noise certification standards 
for issuing type and airworthiness certificates for a new civil, hybrid 
airplane-rotorcraft known as the tiltrotor. This rule proposes to adopt 
the same recommended guidelines for noise certification found in the 
International Civil Aviation Organization (ICAO) Annex 16, Volume 1, 
Chapter 13, Attachment F (Amendment 7) for tiltrotors certificated in 
the United States (U.S.). The ICAO recommended practices are already 
harmonized internationally, and the adoption as standards into our 
regulations would be consistent with the Federal Aviation 
Administration's (FAA) goal of harmonizing U.S. regulations with 
international standards.
    The proposed standards would apply to the issuance of the original 
type certificate, changes to the type certificate, and standard 
airworthiness certificates for tiltrotors.

DATES: Send your comments on or before October 19, 2011.

[[Page 36002]]

ADDRESSES: You may send comments identified by Docket Number [Insert 
docket number, for example, FAA-2011-0629] 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: The FAA will post all comments it receives, without 
change, to http://www.regulations.gov, including any personal 
information the commenter provides. Using the search function of the 
docket Web site, anyone can find and read the electronic form of all 
comments received into any FAA dockets, including the name of the 
individual sending the comment (or signing the comment for an 
association, business, labor union, etc.). DOT's complete Privacy Act 
Statement can be found in the Federal Register published on April 11, 
2000 (65 FR 19477-19478), as well as at http://DocketsInfo.dot.gov.
    Docket: Background documents or comments received may be read at 
http://www.regulations.gov at any time. 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 Sandy Liu, AEE-100, Office of Environment 
and Energy, Federal Aviation Administration, 800 Independence Avenue, 
SW., Washington, DC 20591; telephone: (202) 493-4864; facsimile (202) 
267-5594; e-mail: sandy.liu@faa.gov. For legal questions concerning 
this proposed rule contact Karen Petronis, AGC-200, Office of the Chief 
Counsel, Regulations Division, Federal Aviation Administration, 800 
Independence Avenue, SW., Washington, DC 20591; telephone: (202) 267-
3073; e-mail: karen.petronis@faa.gov.

SUPPLEMENTARY INFORMATION:

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 promulgated under the authority described in 
subtitle VII, part A, subpart III, section 44715, Controlling aircraft 
noise and sonic boom. Under that section, the FAA is charged with 
prescribing regulations to measure and abate aircraft noise. This 
proposed regulation is within the scope of that authority since it 
would establish new noise certification test procedures and noise 
limits for a new class of aircraft. Applicants for type certificates, 
changes in type design, and airworthiness certificates for tiltrotors 
would be required to comply with these new regulations.

Background

    A new aircraft type known as a tiltrotor is currently in 
development after more than six decades. The aircraft uses a hybrid of 
propellers and helicopter rotors to provide both lift and propulsive 
force using rotating nacelles. The aircraft is designed to function as 
a helicopter for takeoff and landing and as an airplane during the en-
route portion of flight operations.
    The most recognizable tiltrotor operating today is the V-22 Osprey 
used by the U.S. Marines and the U.S. Air Force. The V-22 Osprey was 
tailored for the Department of Defense Special Operations Forces and 
can transport 24 fully equipped troops. The proposed civil version of 
the tiltrotor would carry up to nine passengers.
    The tiltrotor concept was first explored for the U.S. Army in the 
mid-1950s as a convertiplane concept that incorporated mixed vertical 
and forward flight capabilities. In 1958, Bell Helicopter Textron Inc. 
(Bell) of Fort Worth, Texas developed the XV-3 tiltrotor for a joint 
research program between the U.S. Army and the U.S. Air Force. The Bell 
XV-3 completed a successful full conversion from vertical flight to 
forward cruise and demonstrated the feasibility of tiltrotor 
technology. Following the U.S. Army and National Aeronautics and Space 
Administration prototype development contract award to Bell in the mid-
1970s, two Bell XV-15 tiltrotor demonstrator aircraft were built as 
predecessors to the V-22 Osprey to demonstrate mature tiltrotor 
technology and flight capabilities.

ICAO Noise Certification Standards

    The ICAO is the international body with responsibility for the 
development of International Standards and Recommended Practices 
pursuant to the Convention on International Civil Aviation (the Chicago 
Convention). Consistent with their obligations under the Chicago 
Convention, Contracting States agree to implement ICAO standards in 
their national regulations to the extent practicable. The standards for 
aircraft noise are contained in Annex 16, Environmental Protection, 
Volume 1, Aircraft Noise.
    In anticipation of civil tiltrotor production, ICAO's Committee on 
Aviation Environmental Protection (CAEP) chartered the Tiltrotor Task 
Group (TRTG) to develop noise certification guidelines for tiltrotors 
in 1997. The FAA participated in the TRTG and its development of the 
tiltrotor noise guidelines from 1997 to 2000. The ICAO tiltrotor 
guidelines used the same noise limits that the United States had 
incorporated into part 36, Appendix H for helicopter noise 
certification. The ICAO has included additional requirements that are 
unique to the design of tiltrotors.
    On June 29, 2001, the TRTG's guidelines were adopted by the ICAO 
Council for incorporation into Annex 16, Volume 1, Chapter 13, 
Attachment F (Amendment 7). The ICAO guidelines became effective on 
October 29, 2001, with an applicability date of March 21, 2002.

Statement of the Problem

    Current regulations in part 36 do not contain noise certification 
requirements specific to the tiltrotor and its unique flight 
capabilities. Since no standards for the tiltrotor currently exist, the 
FAA proposes to adopt the guidelines through rulemaking and add the new 
standards to part 36 and amend Sec.  21.93 (Classification of Changes 
in Type Design) to accommodate certification of the tiltrotor. In order 
to harmonize the U.S. regulations with the international standards, 
this rulemaking proposes the adoption of the same noise certification 
guidelines used in ICAO Annex 16, Volume 1, Chapter 13, Attachment F 
(Amendment 7) for tiltrotors.

Application for Type Certification

    As the tiltrotor concept and technology proved promising with the 
production of the V-22 Osprey, Bell and Agusta-Westland established a 
joint business venture in 1998 to co-develop the Bell/Agusta model 
BA609 civil tiltrotor.
    In August 1996, Bell applied for a U.S. type certificate for the 
model

[[Page 36003]]

BA609 tiltrotor. The BA609 would be type certificated as a ``special 
class'' of aircraft under Sec. Sec.  21.17 and 21.21, using the 
applicable airworthiness provisions of part 25 (Airworthiness 
Standards: Transport Category Airplanes) and part 29 (Airworthiness 
Standards: Transport Category Rotorcraft). This is the first 
application for this class of aircraft. Bell is targeting existing 
helicopter operators as the primary civil market for the BA609, and has 
stated the BA609 could operate from existing heliports without the need 
for new infrastructure to accommodate the aircraft.

General Discussion of the Proposal

    The standards proposed in this rulemaking would apply to the 
issuance of an original type certificate, changes to a type 
certificate, and the issuance of a standard airworthiness certificate 
for tiltrotors. This rulemaking proposes noise certification standards 
that would be applicable to all tiltrotors, including the Bell/Agusta 
Model BA609, which is currently under development. This rule proposes 
to incorporate the guidelines of ICAO Annex 16, Volume 1, Chapter 13, 
Attachment F (Amendment 7) for tiltrotors, consistent with the FAA goal 
of harmonization of regulations with international standards.
    These proposed regulations would:
     Amend Sec.  21.93 for acoustical changes in type design to 
add the tiltrotor as a class of aircraft;
     Amend Sec.  36.1 noise certification standards for the 
issuance of type and airworthiness certificates for the new tiltrotor 
class of aircraft (including the definitions and applicability);
     Add a new Sec.  36.13 acoustical change requirements for 
tiltrotors;
     Add a new subpart K to part 36 that includes noise 
measurement, evaluation and calculation criteria and maximum noise 
limits of tiltrotors;
     Add a new Appendix K to part 36 that includes noise 
certification standards (including the reference test conditions and 
reference test procedures) for tiltrotors certificated in the United 
States.

Paperwork Reduction Act

    The Paperwork Reduction Act of 1995 (44 U.S.C. 3507(d)) requires 
the FAA consider the impact of paperwork and other information 
collection burdens imposed on the public. The FAA has determined there 
would be no new requirement for information collection associated with 
this proposed rule. The requirements are the same as for any other new 
aircraft type certification.

International Compatibility

    In keeping with U.S. obligations under the Convention on 
International Civil Aviation, it is FAA policy to conform our 
regulations to ICAO Standards and Recommended Practices to the maximum 
extent practicable. In 2001, ICAO adopted tiltrotor noise guidelines. 
This proposed regulation will harmonize U.S. noise standards with the 
international standards by adopting the same requirements, adapted for 
the U.S. regulatory format.

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 and Executive Order 13563 direct 
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 (Pub. 
L. 96-354) requires agencies to analyze the economic impact of 
regulatory changes on small entities. Third, the Trade Agreements Act 
(Public Law 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.
    Department of Transportation Order DOT 2100.5 prescribes policies 
and procedures for simplification, analysis, and review of regulations. 
If the expected cost impact is so minimal that a proposed or final rule 
does not warrant a full evaluation, this order permits that a statement 
to that effect and the basis for it be included in the preamble if a 
full regulatory evaluation of the cost and benefits is not prepared. 
Such a determination has been made for this proposed rule. The 
reasoning for this determination follows:
    (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) Would not have a significant economic impact on a substantial 
number of small entities;
    (4) Would not have a significant effect on international trade; and
    (5) Would not impose an unfunded mandate on state, local, or tribal 
governments, or on the private sector by exceeding the monetary 
threshold identified.

These analyses are summarized below.

    The tiltrotor aircraft is a new class of aircraft. Currently there 
are no part 36 certification standards for tiltrotor aircraft. This 
proposed rule would provide for the part 36 certification requirements 
for this new class of aircraft. The benefit of this proposed rule is 
that it would allow the startup and development of a market for a new 
class of aircraft, the tiltrotor. The FAA believes that this would 
result in substantial benefits.
    The potential size of the tiltrotor market can be estimated by the 
sales projections of the current developer, Bell/Agusta. In the next 10 
years, only one model of tiltrotor is expected to be available, the 
BA609 currently in development. The price of a BA609 is expected to be 
$10 to $14 million, up from the original estimate of $7 million to the 
current $14 million. When first priced in 2000, the $7 million price 
was equivalent to the replacement value of a Bell 412 helicopter. The 
BA609 has unique capabilities, such as vertical takeoff and landing, 
combined with the speed and range of a turboprop airplane.
    Bell estimates that it will sell approximately 100 BA609s, making 
the potential near-term tiltrotor market worth a nominal $1 billion to 
$1.4 billion. Table 1 shows the nominal and present value estimates of 
the tiltrotor market. The present value is based on a 7 percent 
discount rate, and a ten year production period with 10 tiltrotors 
being delivered each year. The present value of the tiltrotor market is 
estimated to be between $702,000,000 and $983,000,000.

[[Page 36004]]

                           Table 1--Nominal and Present Value of Tiltrotor Market at a 14,000,000 and 10,000,000 Selling Price
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                Total market value                              Total market value
                                                                         --------------------------------                -------------------------------
                  Year                    Units produced    Unit price                     Present value    Unit price                     Present value
                                                                              Nominal          @ 7%                           Nominal          @ 7%
--------------------------------------------------------------------------------------------------------------------------------------------------------
1.......................................              10     $14,000,000    $140,000,000    $138,844,000     $10,000,000    $100,000,000     $93,460,000
2.......................................              10      14,000,000     140,000,000     122,276,000      10,000,000     100,000,000      87,340,000
3.......................................              10      14,000,000     140,000,000     114,282,000      10,000,000     100,000,000      81,630,000
4.......................................              10      14,000,000     140,000,000     106,806,000      10,000,000     100,000,000      76,290,000
5.......................................              10      14,000,000     140,000,000      99,820,000      10,000,000     100,000,000      71,300,000
6.......................................              10      14,000,000     140,000,000      93,282,000      10,000,000     100,000,000      66,630,000
7.......................................              10      14,000,000     140,000,000      87,178,000      10,000,000     100,000,000      62,270,000
8.......................................              10      14,000,000     140,000,000      81,480,000      10,000,000     100,000,000      58,200,000
9.......................................              10      14,000,000     140,000,000      76,146,000      10,000,000     100,000,000      54,390,000
10......................................              10      14,000,000     140,000,000      71,162,000      10,000,000     100,000,000      50,830,000
                                         ---------------------------------------------------------------------------------------------------------------
Totals..................................             100            N.A.   1,400,000,000     983,276,000            N.A.   1,000,000,000     702,340,000
--------------------------------------------------------------------------------------------------------------------------------------------------------
3/29/2011.

    Table 2 shows the incremental manufacturer costs for the noise 
certification of a civil tiltrotor aircraft. The costs consist of four 
major items: Acoustics; Flight Test; Aircraft; and Miscellaneous. For 
tiltrotor aircraft noise certification, as for any aircraft 
certification, the noise demonstration flight testing and reporting is 
the major incremental cost.
    To meet the proposed requirements of noise control, acoustical 
measurements are used to quantify the characteristic noise levels of 
the aircraft. Almost half the expense ($250,000) is invested in the 
acoustics group equipment and analysis. This cost includes overall 
noise test planning and coordination, noise test site preparation and 
measurement set-up.
    The next highest expense involves the support of the flight test 
group ($220,000). These expenses are needed to configure and prepare 
the aircraft to execute the required noise flight test procedures.
    The last two major expense groups are aircraft and miscellaneous 
expenses. The aircraft expense ($50,000) involves costs associated with 
aircraft flight time, fuel, and flight crew support. Most other general 
expenses of test support are miscellaneous costs ($68,000).
    Issuance of a type certificate requires compliance with the 
applicable noise certification requirements of part 36. Full noise 
certification testing is generally required for new aircraft types and 
for certain voluntary changes to type design that are classified as 
acoustical change under Sec.  21.93(b). The incremental costs recur 
only when a new type certificate is issued, or when a change to a type 
design results when an acoustical change is made.
    As shown in Table 2, the estimated total incremental cost of a 
single noise certification is $588,000. As the $588,000 would be 
incurred in the first year, the nominal value equals the present value. 
The cost estimates for noise certification were prepared by Bell 
Helicopter Textron. The cost of noise certification for the tiltrotor 
is comparable to that for a large helicopter (over 7,000 pounds). Since 
noise testing is required for new aircraft to gain U.S. certification, 
the cost burden is comparable and does not impose any unexpected burden 
on manufacturers.
    The FAA may incur costs in this certification process, including 
the adoption of the new regulations. However, these costs are not 
expected to vary significantly from the agency's current costs to noise 
certificate any other new aircraft type.
    Based on the above analyses, this proposed rule is considered to be 
a minimal cost rule.

   Table 2--Estimated Noise Certification Costs for a Civil Tiltrotor
                                Aircraft
------------------------------------------------------------------------
                                                  Cost per
               Item                   Hours         hour      Total cost
------------------------------------------------------------------------
                          Acoustics Group Items
------------------------------------------------------------------------
Test Plan........................
Test Coordination................
Acoustics/Met/TSPI setup.........
Site Coordination/Survey/
 Preparation.....................
Instrument Calibration...........
Testing..........................
Data Reduction...................
Data Report......................
                                  --------------------------------------
    Hours & Costs Acoustic Group.        2,000         $125     $250,000
------------------------------------------------------------------------
                           Flight Test Groups
------------------------------------------------------------------------
Airspeed Cal.....................
Statement of Conformity..........
Instrument Calibration...........
TSPI pilot guidance and off-site
 ground station development......
Aircraft mods to production-
 representation configuration....
Aircraft instrumentation buildup
 special to noise tests..........

[[Page 36005]]

 
Testing..........................
Aircraft data archiving..........
                                  --------------------------------------
    Hours & Costs Flight Test            2,000          110      220,000
     Groups......................
------------------------------------------------------------------------
                                Aircraft
------------------------------------------------------------------------
(Flight time: Instrumentation
 check out; ferry; & test)
    Miscellaneous flight time....            2        5,000       10,000
    Test flight time.............            8        5,000       40,000
                                  --------------------------------------
        Hours & Costs--Aircraft..           10  ...........       50,000
------------------------------------------------------------------------
                         Miscellaneous Expenses
------------------------------------------------------------------------
Test site lease..................  ...........  ...........       10,000
Off-site equipment rental &        ...........  ...........       10,000
 supplies........................
Equipment shipping & local         ...........  ...........       15,000
 transportation costs (cars,
 pickups)........................
Travel, food, and hotel costs (10  ...........  ...........       33,000
 people* 14 days* $200/day + $500
 airfare per person).............
                                  --------------------------------------
    Costs--Miscellaneous Expenses  ...........  ...........       68,000
                                  --------------------------------------
        Total Hours & Costs......        4,010         N.A.      588,000
------------------------------------------------------------------------
Source: Bell Helicopter Textron, 04/01/2011.

    Since the tiltrotor industry is still developing, the costs and 
benefits discussed are based on a single tiltrotor program. The 
proposed rule would require the noise certification of a tiltrotor 
aircraft type. While the estimated benefits and costs are based on a 
single tiltrotor type, we believe the benefits will exceed the costs 
for any future designs. Bell Agusta anticipates selling 100 tiltrotor 
aircraft, allowing a $1 to $1.4 billion ($700 million to $1billion in 
present value) new market to start up and develop.
    The present value cost of the proposed rule is $588,000 for the 
certification of one aircraft type. The estimated 100 tiltrotor 
aircraft that would be sold would be covered under this type 
certificate, unless major modifications were made that would change the 
original certification. Therefore, the total present value cost of the 
proposed rule is $588,000, which the FAA considers to be minimal.
    Although the FAA cannot quantify the benefits of the proposed rule, 
the FAA believes that the benefits would be substantial. Because of 
this and the minimal cost nature of the proposed rule the FAA believes 
that the proposed rule would be cost beneficial.

Regulatory Flexibility Determination

    The Regulatory Flexibility Act of 1980 (RFA) establishes ``as a 
principle of 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 
businesses, organizations, and governmental jurisdictions subject to 
regulation.'' To achieve 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.
    However, 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.

Tiltrotor Manufacturers

    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 November 5, 2010, and uses the 2007 NAICS codes. All aircraft 
manufacturers are listed in Sector 31-33--Manufacturing; Subsector 
336--Transportation Equipment Manufacturing; NAICS Code 336411--
Aircraft Manufacturing. The small entity size standard is 1,500 
employees.
    Bell Helicopter is a wholly owned subsidiary of Textron Inc. Bell 
Helicopter employed approximately 9,800 employees at the end of 2009 
while Textron employed approximately 32,000 employees. (Textron Fact 
Book 2009). Agusta-Westland is a wholly owned subsidiary of 
Finmeccanica. Agusta-Westland employed 13,886 employees at September 
30, 2010 while Finmeccanica employed 75,733 employees. (Finmeccanica 
Press Release, Rome, 3 November 2010) Since the only tiltrotor 
manufacturer, Bell Helicopter, employs more than 1,500 employees, there 
are no small-entity tiltrotor manufacturers.
    Consequently, the FAA certifies that this proposed rule would not 
have a significant economic impact on a substantial number of small 
tiltrotor manufacturers.

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

[[Page 36006]]

unnecessary obstacles to the foreign commerce of the United States. 
Pursuant to these Acts, the establishment of 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 encourage international trade by using 
international standards as the basis for a rule for the noise 
certification of tiltrotors.

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 one 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 value of $140.8 million in lieu of 
$100 million. This proposed rule does not contain such a mandate; 
therefore, the requirements of Title II do not apply.

Executive Order 13132, Federalism

    The FAA has analyzed this proposed rule under the principles and 
criteria of Executive Order 13132, Federalism. The agency 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.

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. This rule adopts 
internationally established noise guidelines for a new civil, hybrid 
airplane-rotorcraft known as the tiltrotor. Based on the dual 
helicopter and propeller airplane characteristics inherit in the 
tiltrotor, the noise guidelines utilize preexisting helicopter noise 
certification limits and procedures. This rule adopts these noise 
limits to control the harshest (maximum) noise levels when the 
tiltrotor operates in its noisiest configuration--helicopter mode. In 
airplane mode, the tiltrotor is significantly quieter given its low 
cruise RPM design. The FAA finds the applicability of the noise 
guidelines to be technologically and environmentally consistent for 
this new class of aircraft. The tiltrotor will function as a helicopter 
and will follow the same helicopter noise certification requirements, 
thus maintaining a comparable level of environmental protection.
    The FAA has determined this 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, 
Distribution, or Use (May 18, 2001). The agency determined that it is 
not a ``significant energy action'' under the executive order, it is 
not a ``significant regulatory action'' under Executive Order 12866 and 
DOT's Regulatory Policies and Procedures, and 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 or notice 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 21

    Aircraft, Aviation safety, Reporting and recordkeeping 
requirements.

14 CFR Part 36

    Aircraft, Noise control.

The Proposed Amendment

    In consideration of the foregoing, the Federal Aviation 
Administration proposes to amend chapter I of title 14, Code of Federal 
Regulations, as follows:

PART 21--CERTIFICATION PROCEDURES FOR PRODUCTS AND PARTS

    1. The authority citation for part 21 continues to read as follows:

    Authority:  42 U.S.C. 7572; 49 U.S.C. 106(g), 40105, 40113, 
44701-44702, 44704, 44707, 44709, 44711, 44713, 44715, 45303.

    2. Amend Sec.  21.93 by adding paragraph (b)(5) to read as follows:

Sec.  21.93  Classification of changes in type design.

* * * * *
    (b) * * *

[[Page 36007]]

    (5) Tiltrotors.
* * * * *

PART 36--NOISE STANDARDS: AIRCRAFT TYPE AND AIRWORTHINESS 
CERTIFICATION

    3. The authority citation for part 36 continues to read as follows:

    Authority: 42 U.S.C. 4321 et seq.; 49 U.S.C. 106(g), 40113, 
44701-44702, 44704, 44715; sec. 305, Pub. L. 96-193, 94 Stat. 50, 
57; E.O. 11514, 35 FR 4247, 3 CFR, 1966-1970 Comp., p. 902.

    4. Amend Sec.  36.1 as follows:
    A. Add paragraph (a)(5);
    B. Amend paragraph (c) by removing the phrase ``or 36.11'' and 
adding the phrase ``36.11 or 36.13'' in its place; and
    C. Add paragraph (i).
    The additions and revisions read as follows:

Sec.  36.1  Applicability and definitions.

* * * * *
    (a) * * *
    (5) Type certificates, changes to those certificates, and standard 
airworthiness certificates, for tiltrotors.
* * * * *
    (i) For the purpose of showing compliance with this part for 
tiltrotors, the following terms have the specified meanings:
    Airplane mode means a configuration with nacelles on the down stops 
(axis aligned horizontally) and rotor speed set to cruise revolutions 
per minute (RPM).
    Airplane mode RPM means the lower range of rotor rotational speed 
in RPM defined for the airplane mode cruise flight condition.
    Fixed operation points mean designated nacelle angle positions 
selected for airworthiness reference. These are default positions used 
to refer to normal nacelle positioning operation of the aircraft. The 
nacelle angle is controlled by a self-centering switch. When the 
nacelle angle is 0 degrees (airplane mode) and the pilot moves the 
nacelle switch upwards, the nacelles are programmed to automatically 
turn to the first default position (for example, 60 degrees) where they 
will stop. A second upward move of the switch will tilt the nacelle to 
the second default position (for example, 75 degrees). Above the last 
default position, the nacelle angle can be set to any angle up to 
approximately 95 degrees by moving the switch in the up or down 
direction. The number and position of the fixed operation points may 
vary on different tiltrotor configurations.
    Nacelle angle is defined as the angle between the rotor shaft 
centerline and the longitudinal axis of the aircraft fuselage.
    Tiltrotor means a class of aircraft capable of vertical take-off 
and landing, within the powered-lift category, with rotors mounted at 
or near the wing tips that vary in pitch from near vertical to near 
horizontal configuration relative to the wing and fuselage.
    Vertical takeoff and landing (VTOL) mode means the aircraft state 
or configuration having the rotors orientated with the axis of rotation 
in a vertical manner (i.e., nacelle angle of approximately 90 degrees) 
for vertical takeoff and landing operations.
    VCON is defined as the maximum authorized speed for any 
nacelle angle in VTOL/Conversion mode.
    VMCP is defined as the maximum level flight airspeed for 
airplane mode corresponding to minimum specification engine power 
corresponding to maximum continuous power available for sea level 
pressure of 2,116 pounds per square foot (1,013.25 hPa), at 77[deg] 
Fahrenheit (25[deg] Celsius) ambient conditions at the relevant maximum 
certificated weight (mass).
    VMO is defined as the maximum airspeed in airplane mode 
that may not be deliberately exceeded.
    VTOL/Conversion mode is all approved nacelle positions where the 
design operating rotor speed is used for hover operations.
    VTOL mode RPM means highest range of RPM that occur for takeoff, 
approach, hover, and conversion conditions.
    5. Add Sec.  36.13 to subpart A to read as follows:

Sec.  36.13  Acoustical change: Tiltrotor aircraft.

    The following requirements apply to tiltrotors in any category for 
which an acoustical change approval is applied for under Sec.  21.93(b) 
of this chapter on or after [effective date of final rule]:
    (a) In showing compliance with Appendix K of this part, noise 
levels must be measured, evaluated, and calculated in accordance with 
the applicable procedures and conditions prescribed in Appendix K of 
this part.
    (b) Compliance with the noise limits prescribed in section 4 of 
Appendix K of this part must be shown in accordance with the applicable 
provisions of sections K2 (Noise Evaluation Measure), K3 (Noise 
Measurement Reference Points), K6 (Noise Certification Reference 
Procedures), and K7 (Test Procedures) of Appendix K of this part.
    (c) After a change in type design, tiltrotor noise levels may not 
exceed the limits specified in Sec.  36.1103.
    6. Add Subpart K of part 36 to read as follows:

Subpart K--Tiltrotors

Sec.  36.1101  Noise measurement and evaluation.

    For tiltrotors, the noise generated must be measured and evaluated 
under Appendix K of this part, or under an approved equivalent 
procedure.

Sec.  36.1103  Noise limits.

    (a) Compliance with the maximum noise levels prescribed in Appendix 
K of this part must be shown for a tiltrotor for which the application 
for the issuance of a type certificate is made on or after [effective 
date of the final rule].
    (b) To demonstrate compliance with this part, noise levels may not 
exceed the noise limits listed in section K4 of Appendix K of this 
part. Appendix K of this part (or an approved equivalent procedure) 
must also be used to evaluate and demonstrate compliance with the 
approved test procedures, and at the applicable noise measurement 
points.
    7. Add Appendix K of part 36 to read as follows:

Appendix K to Part 36--Noise Requirements for Tiltrotors Under Subpart 
K

Sec.
K1 General
K2 Noise Evaluation Measure
K3 Noise Measurement Reference Points
K4 Noise Limits
K5 Trade-offs
K6 Noise Certification Reference Procedures
K7 Test Procedures

Section K1 General

    This appendix prescribes noise limits and procedures for 
measuring noise and adjusting the data to standard conditions for 
tiltrotors as specified in Sec.  36.1 of this part.

Section K2 Noise Evaluation Measure

    The noise evaluation measure is the effective perceived noise 
level in EPNdB, to be calculated in accordance with section A36.4 of 
Appendix A of this part, except corrections for spectral 
irregularities must be determined using the 50 Hertz sound pressure 
level found in section H36.201 of Appendix H of this part.

Section K3 Noise Measurement Reference Points

    The following noise reference points must be used when 
demonstrating tiltrotor compliance with section K6 (Noise 
Certification Reference Procedures) and section K7 (Test Procedures) 
of this appendix:
    (a) Takeoff reference noise measurement points--
    As shown in Figure K1 below:
    (1) The centerline noise measurement flight path reference 
point, designated A, is located on the ground vertically below the 
reference takeoff flight path. The

[[Page 36008]]

measurement point is located 1,640 feet (500 m) in the horizontal 
direction of flight from the point Cr where transition to climbing 
flight is initiated, as described in section K6.2 of this appendix;
    (2) Two sideline noise measurement points, designated as 
S(starboard) and S(port), are located on the ground perpendicular to 
and symmetrically stationed at 492 feet (150 m) on both sides of the 
takeoff reference flight path. The measurement points bisect the 
centerline flight path reference point A.
[GRAPHIC] [TIFF OMITTED] TP21JN11.027

    (b) Flyover reference noise measurement points--
    As shown in Figure K2 below:
    (1) The centerline noise measurement flight path reference 
point, designated A, is located on the ground 492 feet (150 m) 
vertically below the reference flyover flight path. The measurement 
point is defined by the flyover reference procedure in section K6.3 
of this appendix;
    (2) Two sideline noise measurement points, designated as 
S(starboard) and S(port), are located on the ground perpendicular to 
and symmetrically stationed at 492 feet (150 m) on both sides of the 
flyover reference flight path. The measurement points bisect the 
centerline flight path reference point A.

[[Page 36009]]

[GRAPHIC] [TIFF OMITTED] TP21JN11.028

    (c) Approach reference noise measurement points--
    As shown in Figure K3 below:
    (1) The centerline noise measurement flight path reference 
point, designated A, is located on the ground 394 feet (120 m) 
vertically below the reference approach flight path. The measurement 
point is defined by the approach reference procedure in section K6.4 
of this appendix. On level ground, the measurement point corresponds 
to a position 3,740 feet (1,140 m) from the intersection of the 6.0 
degree approach path with the ground plane;
    (2) Two sideline noise measurement points, designated as 
S(starboard) and S(port), are located on the ground perpendicular to 
and symmetrically stationed at 492 feet (150 m) on both sides of the 
approach reference flight path. The measurement points bisect the 
centerline flight path reference point A.
[GRAPHIC] [TIFF OMITTED] TP21JN11.029

[[Page 36010]]

Section K4 Noise Limits

    For a tiltrotor, the maximum noise levels, as determined in 
accordance with the noise evaluation in EPNdB and calculation method 
described in section H36.201 of Appendix H of this part, must not 
exceed the noise limits as follows:
    (a) At the takeoff flight path reference point: For a tiltrotor 
having a maximum certificated takeoff weight (mass) of 176,370 
pounds (80,000 kg) or more, in VTOL/Conversion mode, 109 EPNdB, 
decreasing linearly with the logarithm of the tiltrotor weight 
(mass) at a rate of 3 EPNdB per halving of weight (mass) down to 89 
EPNdB, after which the limit is constant. Figure K4 illustrates the 
takeoff noise limit as a solid line.
    (b) At the Flyover path reference point: For a tiltrotor having 
a maximum certificated takeoff weight (mass) of 176,370 pounds 
(80,000 kg) or more, in VTOL/Conversion mode, 108 EPNdB, decreasing 
linearly with the logarithm of the tiltrotor weight (mass) at a rate 
of 3 EPNdB per halving of weight (mass) down to 88 EPNdB, after 
which the limit is constant. Figure K4 illustrates the flyover noise 
limit as a dashed line.
    (c) At the approach flight path reference point: For a tiltrotor 
having a maximum certificated takeoff weight (mass) of 176,370 
pounds (80,000 kg) or more, in VTOL/Conversion mode, 110 EPNdB, 
decreasing linearly with the logarithm of the tiltrotors weight 
(mass) at a rate of 3 EPNdB per halving of weight (mass) down to 90 
EPNdB, after which the limit is constant. Figure K4 illustrates the 
approach noise limit as a dash-dot line.
[GRAPHIC] [TIFF OMITTED] TP21JN11.030

Section K5 Trade-Offs

    If the noise evaluation measurement exceeds the noise limits 
described in K4 of this appendix at one or two measurement points:
    (a) The sum of excesses must not be greater than 4 EPNdB;
    (b) The excess at any single point must not be greater than 3 
EPNdB; and
    (c) Any excess must be offset by the remaining noise margin at 
the other point or points.

Section K6 Noise Certification Reference Procedures

K6.1 General Conditions

    (a) [Reserved]
    (b) [Reserved]
    (c) The takeoff, flyover and approach reference procedures must 
be established in accordance with sections K6.2, K6.3 and K6.4 of 
this appendix, except as specified in section K6.1(d) of this 
appendix.
    (d) When the design characteristics of the tiltrotor prevent 
test flights to be conducted in accordance with section K6.2, K6.3 
or K6.4 of this appendix, the applicant must revise

[[Page 36011]]

the test procedures and resubmit the procedures for approval.
    (e) The following reference atmospheric conditions must be used 
to establish the reference procedures:
    (1) Sea level atmospheric pressure of 2,116 pounds per square 
foot (1,013.25 hPa);
    (2) Ambient air temperature of 77[deg] Fahrenheit (25[deg] 
Celsius, i.e., ISA + 10 [deg]C);
    (3) Relative humidity of 70 percent; and
    (4) Zero wind.
    (f) For tests conducted in accordance with sections K6.2, K6.3, 
and K6.4 of this appendix, use the maximum normal operating RPM 
corresponding to the airworthiness limit imposed by the 
manufacturer. For configurations for which the rotor speed 
automatically links with the flight condition, use the maximum 
normal operating rotor speed corresponding for that flight 
condition. For configurations for which the rotor speed can change 
by pilot action, use the highest normal rotor speed specified in the 
flight manual limitation section for power-on conditions.
    K6.2 Takeoff Reference Procedure. The takeoff reference flight 
procedure is as follows:
    (a) A constant takeoff configuration must be maintained, 
including the nacelle angle selected by the applicant;
    (b) The tiltrotor power must be stabilized at the maximum 
takeoff power corresponding to the minimum installed engine(s) 
specification power available for the reference ambient conditions 
or gearbox torque limit, whichever is lower. The tiltrotor power 
must also be stabilized along a path starting from a point located 
1,640 feet (500 m) before the flight path reference point, at 65 ft 
(20 m) above ground level;
    (c) The nacelle angle and the corresponding best rate of climb 
speed, or the lowest approved speed for the climb after takeoff, 
whichever is the greater, must be maintained throughout the takeoff 
reference procedure;
    (d) The rotor speed must be stabilized at the maximum normal 
operating RPM certificated for takeoff;
    (e) The weight (mass) of the tiltrotors must be the maximum 
takeoff weight (mass) as requested for noise certification; and
    (f) The reference takeoff flight profile is a straight line 
segment inclined from the starting point 1,640 feet (500 m) before 
to the center noise measurement point and 65 ft (20 m) above ground 
level at an angle defined by best rate of climb and the speed 
corresponding to the selected nacelle angle and for minimum 
specification engine performance.
    K6.3 Flyover Reference Procedure. The flyover reference flight 
procedure is as follows:
    (a) The tiltrotor must stabilize for level flight along the 
centerline flyover flight path and over the noise measurement 
reference point at an altitude of 492 ft (150 m) above ground level;
    (b) A constant flyover configuration must be maintained;
    (c) The weight (mass) of the tiltrotor must be the maximum 
takeoff weight (mass) as requested for noise certification;
    (d) In the VTOL/Conversion mode:
    (1) The nacelle angle must be at the authorized fixed operation 
point that is closest to the shallow nacelle angle certificated for 
zero airspeed;
    (2) The airspeed must be 0.9VCON; and
    (3) The rotor speed must be stabilized at the maximum normal 
operating RPM certificated for level flight.
    K6.4 Approach Reference Procedure. The approach reference 
procedure is as follows:
    (a) The tiltrotor must be stabilized to follow a 6.0 degree 
approach path;
    (b) An approved airworthiness configuration in which maximum 
noise occurs must be maintained;
    (1) An airspeed equal to the best rate of climb speed 
corresponding to the nacelle angle, or the lowest approved airspeed 
for the approach, whichever is greater, must be stabilized and 
maintained; and
    (2) The tiltrotor power during the approach must be stabilized 
over the flight path reference point, and continue to a landing;
    (c) The rotor speed must stabilize at the maximum normal 
operating RPM certificated for approach;
    (d) The constant approach configuration used in airworthiness 
certification tests, with the landing gear extended, must be 
maintained; and
    (e) The weight (mass) of the tiltrotor at landing must be the 
maximum landing weight (mass) as requested for noise certification.

Section K7 Test Procedures

    K7.1 [Reserved]
    K7.2 The test procedures and noise measurements must be 
conducted and processed to yield the noise evaluation measure 
designated in section K2 of this appendix.
    K7.3 If either the test conditions or test procedures do not 
conform to the applicable noise certification reference conditions 
or procedures prescribed by this part, the applicant must apply the 
correction methods described in section H36.205 of Appendix H of 
this part to the acoustic test data measured.
    K7.4 Adjustments for differences between test and reference 
flight procedures must not exceed:
    (a) For takeoff: 4.0 EPNdB, of which the arithmetic sum of delta 
1 and the term -7.5 log (QK/QrKr) from delta 2 must not in total 
exceed 2.0 EPNdB;
    (b) For flyover or approach: 2.0 EPNdB.
    K7.5 The average rotor RPM must not vary from the normal maximum 
operating RPM by more than +/-1.0 percent during the 10 dB-down time 
interval.
    K7.6 The tiltrotor airspeed must not vary from the reference 
airspeed appropriate to the flight demonstration by more than +/-9 
km/h (5 kts) throughout the 10 dB-down time interval.
    K7.7 The number of level flyovers made with a head wind 
component must be equal to the number of level flyovers made with a 
tail wind component.
    K7.8 The tiltrotor must operate between +/-10 degrees from the 
vertical or between +/-65 feet (+/-20 m) lateral deviation 
tolerance, whichever is greater, above the reference track and 
throughout the 10 dB-down time interval.
    K7.9 The tiltrotor altitude must not vary during each flight by 
more than +/-30 ft (+/-9 m) from the reference altitude at the 
overhead point.
    K7.10 During the approach procedure, the tiltrotor must 
establish a stabilized constant speed approach and fly between 
approach angles of 5.5 degrees and 6.5 degrees.
    K7.11 During all test procedures, the tiltrotor weight (mass) 
must not be less than 90 percent and not more than 105 percent of 
the maximum certificated weight (mass). For each of the test 
procedures, complete at least one test at or above this maximum 
certificated weight (mass).
    K7.12 A tiltrotor capable of carrying external loads or external 
equipment must be noise certificated without such loads or equipment 
fitted.
    K7.13 The values of VCON and VMCP or 
VMO used for noise certification must be included in the 
approved Flight Manual.

    Issued in Washington, DC, on June 10, 2011.
Lourdes Maurice,
Director, Office of Environment and Energy.

[FR Doc. 2011-15276 Filed 6-20-11; 8:45 am]
BILLING CODE 4910-13-P