3782 Federal Register / Vol. 86, No. 10 / Friday, January 15, 2021 / Rules and Regulations 

certified that this rule, when 

promulgated, does not have a significant 

economic impact on a substantial 

number of small entities under the 

criteria of the Regulatory Flexibility Act. 

Environmental Review 

The FAA has determined that this 

action qualifies for categorical exclusion 

under the National Environmental 

Policy Act in accordance with FAA 

Order 1050.1F, ‘‘Environmental 

Impacts: Policies and Procedures,’’ 

paragraph 5–6.5.a. This airspace action 

is not expected to cause any potentially 

significant environmental impacts, and 

no extraordinary circumstances exist 

that warrant preparation of an 

environmental assessment. 

Lists of Subjects in 14 CFR Part 71 

Airspace, Incorporation by reference, 

Navigation (air). 

Adoption of the Amendment 

In consideration of the foregoing, the 

Federal Aviation Administration 

amends 14 CFR part 71 as follows: 

PART 71—DESIGNATION OF CLASS A, 

B, C, D, AND E AIRSPACE AREAS; AIR 

TRAFFIC SERVICE ROUTES; AND 

REPORTING POINTS 

■ 1. The authority citation for part 71 

continues to read as follows: 

Authority: 49 U.S.C. 106(f), 106(g); 40103, 

40113, 40120; E.O. 10854, 24 FR 9565, 3 CFR, 

1959–1963 Comp., p. 389. 

§ 71.1 [Amended] 

■ 2. The incorporation by reference in 

14 CFR 71.1 of FAA Order 7400.11E, 

Airspace Designations and Reporting 

Points, dated July 21, 2020, and 

effective September 15, 2020, is 

amended as follows: 

Paragraph 6005 Class E Airspace Areas 

Extending Upward from 700 feet or More 

Above the Surface of the Earth. 

* * * * * 

AGL WI E5 Prairie Du Chien, WI 

[Amended] 

Prairie Du Chien Municipal Airport, WI 

(Lat. 43°01′09′′ N, long. 91°07′25′′ W) 

That airspace extending upward from 700 

feet above the surface within a 6.6-mile 

radius of Prairie Du Chien Municipal Airport, 

and within 1 mile each side of the 110° 

bearing from the airport extending from the 

6.6-mile radius to 6.8 miles east of the 

airport, and within 1 mile each side of the 

140° bearing from the airport extending from 

the 6.6-mile radius to 10.4 miles southeast of 

the airport, and within 1 mile each side of 

the 320° bearing from the airport extending 

from the 6.6-mile radius to 10.6 miles 

northwest of the airport. 

Issued in Fort Worth, Texas, on January 4, 

2021. 

Martin A. Skinner, 

Acting Manager, Operations Support Group, 

ATO Central Service Center. 

[FR Doc. 2021–00022 Filed 1–14–21; 8:45 am] 

BILLING CODE 4910–13–P 

DEPARTMENT OF TRANSPORTATION 

Federal Aviation Administration 

14 CFR Part 91 

[Docket No.: FAA–2019–0451; Amdt. No. 

91–362] 

RIN 2120–AL30 

Special Flight Authorizations for 

Supersonic Aircraft 

AGENCY: Federal Aviation 

Administration (FAA), Department of 

Transportation (DOT). 

ACTION: Final rule. 

SUMMARY: In consideration of the 

continuing development of a new 

generation of supersonic aircraft, FAA is 

modernizing the procedure for 

requesting a special flight authorization 

to operate in excess of Mach 1 over land 

in the United States. The renewed 

interest in development of supersonic 

airplanes caused FAA to review its 

application procedures that allow for 

flight tests of these aircraft. This final 

rule modifies the criteria for applying 

for these authorizations and moves the 

material from an appendix to a 

regulation to make it easier to find and 

understand. Outside the context of 

special flight authorizations under this 

final rule, the FAA continues generally 

to prohibit civil supersonic flight over 

land in the United States. 

DATES: Effective February 16, 2021. 

ADDRESSES: For information on where to 

obtain copies of rulemaking documents 

and other information related to this 

final rule, see ‘‘How To Obtain 

Additional Information’’ in the 

SUPPLEMENTARY INFORMATION section of 

this document. 

FOR FURTHER INFORMATION CONTACT: For 

questions concerning this action, 

contact: Sandy Liu, Office of 

Environment and Energy, AEE–100, 

Federal Aviation Administration, 800 

Independence Avenue SW, Washington, 

DC 20591; telephone (240) 267–4748; 

email sandy.liu@faa.gov. 

SUPPLEMENTARY INFORMATION: 

Authority for This Rulemaking 

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, FAA is 

charged with prescribing regulations to 

measure and abate aircraft noise. This 

regulation is within the scope of that 

authority since it provides for certain 

operations of new supersonic aircraft in 

approved areas where the 

environmental impact of the operations 

has been assessed. 

I. Overview of Final Rule 

This rulemaking amends the 

administrative requirements for a 

special flight authorization originally 

published as appendix B to part 91, 

Authorizations to exceed Mach 1 

(§ 91.817), of title 14 of the Code of 

Federal Regulations (14 CFR). This 

rulemaking is intended to streamline the 

application procedure for these special 

flight authorizations by clarifying the 

information that is needed for 

submission and specifying the program 

office within FAA that processes the 

applications. This rule sets forth the 

application criteria in a more userfriendly format. FAA is adopting the 

rule largely as it was proposed, with 

some minor changes to the regulatory 

text, as discussed in Section IV and the 

accompanying preamble discussion. 

II. Background 

In a notice of proposed rulemaking 

(NPRM) titled Special Flight 

Authorizations for Supersonic Aircraft 

(84 FR 30961, June 28, 2019), FAA 

proposed to modernize the procedures 

for requesting special flight 

authorizations that are needed to 

accomplish testing and development of 

new supersonic aircraft. The NPRM 

provided a brief history of FAA’s 

regulation of civil supersonic aircraft 

beginning in the 1970s with the 

introduction of the Concorde, including 

the history of the application procedure 

for special flight authorizations that is 

the subject of this rulemaking. 

FAA is clarifying the application 

procedure for requesting a special flight 

authorization to fly faster than Mach 1 

following increased interest by industry 

to develop such aircraft. The revisions 

adopted here do not change the general 

prohibition against overland supersonic 

flight in the United States that has been 

in place since 1973 (14 CFR 91.817). 

This rule replaces the procedure 

described in part 91, appendix B, with 

regulatory text that clearly describes the 

Federal Register / Vol. 86, No. 10 / Friday, January 15, 2021 / Rules and Regulations 3783 

1The National Environmental Policy Act of 1969 

(42 U.S.C. 4321 et seq.) 

application process and criteria. The 

new regulation provides clarity, 

includes noise testing as another reason 

for which an authorization may be 

issued, and requires one additional 

piece of information to be provided in 

an application, which is discussed 

below. This rule does not introduce any 

new FAA policy or change the intent of 

the original application process. 

Recognizing the renewed interest of 

the aviation industry in developing 

supersonic aircraft, Congress instructed 

FAA in Section 181 of the FAA 

Reauthorization Act of 2018 (Pub. L. 

115–254, Oct. 5, 2018) to assume a 

leadership role in the development of 

international policies, regulations, and 

standards that facilitate the safe and 

efficient operation of such aircraft. 

Section 181 further directed FAA to 

undertake reforms of its regulations 

regarding civil supersonic aircraft. 

FAA’s first step in response to Section 

181 was to propose changes to the 

special flight authorization application 

process. The second step was FAA’s 

publication of an NPRM that proposes 

landing and takeoff noise limits under 

14 CFR part 36 for the first group of 

supersonic aircraft expected to be 

presented for certification (85 FR 20431, 

Apr. 13, 2020). The relationship 

between the two rulemakings is 

minimal. An aircraft developer would 

eventually use the final rule adopted 

here to test aircraft under development 

at supersonic speed. Eventually, a 

developer might further use the 

authorization procedure adopted here 

for flight tests to demonstrate 

compliance with certain supersonic 

noise criteria when those criteria are 

eventually adopted. The part 36 NPRM, 

by contrast, included only subsonic 

standards for new supersonic aircraft 

and addressed the noise limits for 

landing and takeoff. Because landing 

and takeoff do not occur at supersonic 

speeds, a special flight authorization 

under this final rule would be 

unnecessary to test for landing and 

takeoff noise levels of supersonic 

aircraft, just as subsonic aircraft do not 

require such special permission to 

accomplish part 36 testing. 

Neither this final rule nor the part 36 

noise limit NPRM alters the general 

prohibition on supersonic flight over 

land in the United States found in 

§ 91.817. 

Summary of the NPRM 

This modernization of the 

authorization process for certain civil 

supersonic flights is intended to 

simplify and clarify the process for 

applicants interested in obtaining an 

authorization to perform supersonic 

aircraft development testing. 

In the proposed rule, FAA identified 

three areas intended to improve 

provisions that comprised appendix B. 

The first designated the proposed office 

in FAA to which applicants are to send 

applications and direct questions. The 

second proposed to gather the scattered 

application requirements into a list, and 

present them according to modern 

regulatory formatting standards. As part 

of this effort, FAA proposed also to 

correct the regulatory text for 

consistency throughout the new section. 

Third, FAA proposed the addition of a 

new reason for flight testing to 

accommodate future noise certification 

actions. 

The NPRM invited interested persons 

to participate in the rulemaking by 

submitting written comments, data, or 

views. It also invited comments relating 

to the economic, environmental, energy, 

or federalism impacts that might result 

from adopting the proposal. 

III. Discussion of Public Comments 

FAA received a total of 206 comments 

on the NPRM: 43 comments generally 

supported the NPRM, 45 generally 

opposed the NPRM, and 118 are 

considered outside the scope of the rule. 

The majority of comments from the 

public focused on the current routing of 

aircraft under the NextGen program, or 

expressed general annoyance regarding 

aircraft noise, and did not include any 

comments specific to the proposal 

updating the application procedure. 

A. General Environmental Concerns 

Regarding Civil Supersonic Flight 

Approximately 77 commenters 

included some combination of general 

concerns about the possible 

environmental effects of supersonic 

airplanes—whether they were about the 

noise anticipated from new supersonic 

airplanes, the effect of supersonic 

operations on the atmosphere, or both. 

Some commenters generally cited the 

Concorde model airplanes as an 

example. Those opposing the rule, 

including two municipalities, stated 

their opposition to the addition of 

supersonic airplanes, citing detrimental 

environmental effects, but did not 

comment on the changes proposed for 

the application procedure. 

In response, FAA emphasizes that the 

proposed rule would not have allowed 

supersonic flights to occur on a regular 

basis in the United States. The 

regulation that generally prohibits civil 

airplanes from operating at speeds in 

excess of Mach 1 over land in the 

United States (14 CFR 91.817) has been 

in effect since 1973, and no change to 

that regulation was proposed. 

Rather, the proposed rule focused on 

the administrative application process 

for special flight authorizations to 

exceed Mach 1 for certain reasons, and 

for flight in limited areas that would be 

determined in advance. The rule does 

not in and of itself authorize the 

operation of any specific airplane over 

any particular area; rather, any flights 

authorized under the rule could only 

occur upon receiving FAA authorization 

after completion of the application 

process and considerable regulatory 

prerequisites, including analyses of the 

environmental impacts on the area over 

which an applicant proposes to operate, 

as required by law. Neither these 

regulatory prerequisites nor the 

assessments of environmental impacts 

were the subject of FAA’s proposed 

changes. Comments that suggested 

changes to the required assessments 

were beyond the scope of this 

rulemaking. 

The special flight authorizations that 

are the subject of this rulemaking have 

been available since the FAA adopted 

the supersonic prohibition in 1973. This 

rulemaking only presents an update of 

the administrative application process, 

without affecting FAA’s underlying 

duty to assess the environmental impact 

of any flight it authorizes, whether 

under the National Environmental 

Policy Act (NEPA) or the requirements 

imposed by the regulation itself. 

B. The National Environmental Policy 

Act (NEPA) 

Paragraph (b) of appendix B to part 91 

directed applicants generally to submit 

‘‘all information requested by the 

Administrator’’ necessary for the 

Administrator to make a determination 

under the National Environmental 

Policy Act (NEPA).1 In the proposed 

rule, FAA tried to provide applicants 

with better clarity by adding the text in 

proposed § 91.818(c)(2)(i)–(iii) to 

suggest the form that such information 

might take to support FAA’s NEPA 

determination. Specifically, the 

proposed language gave as examples an 

Environmental Impact Statement (EIS) 

for the proposed flight area, an EIS 

previously prepared for the proposed 

flight area, or another statement or 

finding of environmental impact for the 

proposed flight test area, such as an 

Environmental Assessment (EA). 

In the final rule, FAA revises 

§ 91.818(c)(2) to remove these 

suggestions, because they proved to be 

a source of confusion among 

3784 Federal Register / Vol. 86, No. 10 / Friday, January 15, 2021 / Rules and Regulations 

2 40 CFR parts 1500 through 1508 (2020). 

3The CEQ regulations were updated in July 2020, 

while this final rule was in process. See 85 FR 

43304 (July 16, 2020). The revised CEQ regulations 

became effective on September 14, 2020. 

4The regulation states that ‘‘an agency may 

require an applicant to submit environmental 

information for possible use by the agency in 

preparing an environmental document.’’ The 

regulation does not allow the agency to use such 

information without considerable additional 

analysis and verification. 

5FAA’s NEPA procedures, as set forth in FAA 

Order 1050.1F, Environmental Impacts: Policies 

and Procedures (July, 2015), do not currently have 

a categorical exclusion that would be applicable to 

applications for special flight authorizations. 

Accordingly, current FAA policy would not allow 

application of a categorical exclusion. However, as 

discussed further below, FAA might be able to 

establish an applicable categorical exclusion, but 

only after following appropriate procedures. 

commenters, as discussed below. The 

proposed language providing more 

detail about what an applicant could 

submit was not intended to imply that 

FAA would forego independently 

evaluating the information or closely 

examining the environmental impacts 

on a proposed test area in determining 

whether to grant a particular special 

flight authorization. The language was 

also not intended to imply shifting the 

burden of complying with NEPA to the 

applicant rather than FAA. 

NEPA requires Federal agencies to 

consider the environmental impacts of 

their actions in their decision-making 

processes. Specifically, an agency must 

determine whether the action it is 

considering (in this case, whether to 

issue a special flight authorization 

allowing one or more supersonic flights) 

constitutes a ‘‘major Federal action 

significantly affecting the quality of the 

human environment’’ (i.e., whether a 

proposed action would have significant 

environmental impact). FAA makes this 

determination in accordance with 

Council on Environmental Quality 

(CEQ) regulations,2 which provide the 

procedural requirements for Federal 

agency compliance with NEPA. 

CEQ regulations include, at 40 CFR 

1506.5, the option for agencies to seek 

necessary information from applicants 

to support the agency’s required 

environmental review of proposed 

Federal actions under NEPA.3 That 

analysis may require varying amounts 

and types of data to make the 

determination whether approval of the 

underlying request would result in 

significant environmental impacts. 

In order to complete that analysis in 

a timely fashion, FAA benefits from 

applicants’ providing as much of the 

information as they can, in accordance 

with 40 CFR 1506.5.4 That information 

may be incorporated into an EA or EIS 

that is developed subject to FAA 

supervision, or it may provide the basis 

for FAA to apply a categorical exclusion 

of the action from further NEPA 

review.5

Nothing in the special flight 

authorization regulation, however, 

either requires or permits applicants for 

special flight authorizations to 

determine what level of NEPA review is 

required or whether issuance of a 

special flight authorization would have 

significant environmental impacts. 

Those determinations are FAA’s alone. 

Further, FAA’s finding under NEPA 

regarding the significance of 

environmental effects is not dispositive 

of the application under consideration. 

The NEPA analysis informs FAA’s 

decision on whether to grant a special 

flight authorization for supersonic flight 

over a certain area, and the NEPA 

analysis must be completed before a 

decision to grant a special flight 

authorization. However, the NEPA 

determination (regarding significance of 

the environmental effects of granting the 

authorization) is distinct from the 

Administrator’s findings on the 

application as a whole. The 

circumstances behind each application 

will be unique. Under § 91.818(c)(1) of 

the final rule, the application is denied 

if the Administrator finds that such 

action is necessary to protect or enhance 

the environment. 

Because both the NEPA determination 

referenced in § 91.818(c)(2) and the 

substantive finding that can be made 

under § 91.818(c)(1) are environmental 

in nature, the final rule is revised to 

guard against the risk of the two being 

conflated. Specifically, § 91.818(c)(2) as 

adopted focuses more expressly on 

supporting the NEPA significance 

determination, which better 

distinguishes the purpose of paragraph 

(c)(2) from the purpose of an 

Administrator finding made under 

paragraph (c)(1) of that section. 

Boom Technology (Boom) submitted a 

comment regarding streamlining the 

NEPA process in the context of special 

flight authorizations. Boom initially 

presents two factual conclusions. 

Boom’s first conclusion is that FAA 

would be unlikely to identify any 

significant sonic boom noise impacts for 

individual supersonic flight test 

programs under the FAA’s threshold of 

significance for noise impacts in its 

NEPA procedures (FAA Order 1050.1). 

Boom’s second conclusion is that the 

FAA programmatically could examine 

all supersonic test flight campaigns 

covering all applicants in a single year 

without the impacts triggering the 

FAA’s threshold of significance for 

noise. Boom supports these conclusions 

with metrics from previous flights of the 

SpaceX Falcon Heavy landings and 

operations of the Concorde. Based on its 

conclusion that impacts of special flight 

authorizations would never reach FAA’s 

threshold of significance for noise 

impacts, either individually or 

cumulatively on an annual basis, Boom 

proposes a series of qualifying criteria 

that, if met, should lead FAA to 

presume no significant impacts exist. 

FAA finds that this proposal fails for 

two reasons. First, as Boom 

acknowledged, FAA may use 

supplemental metrics when evaluating 

noise, and gives special consideration to 

certain types of noise-sensitive areas 

where the standard significance 

threshold may not adequately capture 

environmental effects. Although FAA 

uses all available methods to increase 

efficiency in its environmental review 

process, and in appropriate individual 

circumstances could make a finding of 

no significant impact for some or even 

most special flight authorizations, it 

cannot prejudge the outcome of 

individual applications submitted under 

this regulation, or their effects if 

considered cumulatively on an annual 

basis. 

Second, Boom’s proposal to create 

criteria that, if satisfied, create a 

presumption that no significant effects 

will occur appears to be consistent with 

establishing a categorical exclusion 

under 40 CFR 1501.4. Categorical 

exclusions are categories of actions that 

in ordinary circumstances do not have 

significant individual or cumulative 

impacts on the quality of the human 

environment. However, although Boom 

suggested that the Administrator could 

use this rulemaking to establish that the 

collective level of noise generated by all 

foreseeable test activities is not 

environmentally significant if 

conducted pursuant to these particular 

conditions, categorical exclusions must 

be identified in agency NEPA 

procedures and are subject to the 

requirements for public review and 

review by CEQ as specified in 40 CFR 

1507.3. Moreover, the anecdotal 

evidence offered by Boom related to 

flights of other aircraft that were not 

subject to § 91.817 would not be 

sufficient to establish a categorical 

exclusion under NEPA with respect to 

supersonic flights requested in a special 

flight authorization. The establishment 

of ‘‘parameters’’ relating to the NEPA 

review of supersonic flight tests would 

require an analysis of part 91 operations 

in order to justify a categorical 

exclusion, and the supporting 

documentation would need to go 

through the public process required for 

all changes to FAA’s NEPA procedures 

Federal Register / Vol. 86, No. 10 / Friday, January 15, 2021 / Rules and Regulations 3785 

as set forth in Order 1050.1F. Although 

at some point in the future FAA might 

undertake the necessary analysis and 

public review process to establish such 

a categorical exclusion, absent a change 

to Order 1050.1F, FAA currently must 

individually consider the potential 

environmental impacts of requested 

special flight authorizations. 

Boom also commented on an aspect of 

the proposed standard for special flight 

authorization operations outside the test 

area—in particular, that the operation 

does not cause a measurable sonic boom 

overpressure outside the test area. While 

that topic is discussed below, Boom’s 

characterization of it in the context of 

NEPA is relevant here. Boom indicated 

that the standard (unchanged from 

appendix B) ‘‘goes far beyond what is 

required under the National 

Environmental Policy Act, as allowance 

of measurable overpressure is not 

necessarily a major Federal action 

‘significantly affecting the quality of the 

human environment’ as interpreted 

under agency guidance under Order 

1050.1F . . .’’ Boom inaccurately 

combined the scope of the regulation 

governing the consideration and 

approval of special flight authorizations 

itself with the process tool of NEPA and 

FAA Order 1050.1F, which describes 

FAA’s NEPA policy and procedures. 

Further, Boom does not accurately 

reflect the definition of a major Federal 

action as defined by the CEQ regulations 

and FAA, relying on concepts actually 

related to significance of effects of a 

Federal action. The overpressure 

measurement standard is a specific 

factor set forth in the regulation that 

considers the effect of the proposed 

flights and is relevant for substantive 

approval purposes under the regulation. 

While this information may also be 

considered in NEPA analysis, it does 

not dictate that analysis, nor does it 

affect the process that FAA follows to 

reach a finding regarding significance of 

impacts under NEPA. 

The Center for Biological Diversity 

(CBD) made several arguments with 

regard to NEPA requirements in its 

comment. In part, the CBD read the 

proposed rule to ‘‘suggest that 

preparation of an EA will fulfill FAA’s 

duties’’ under NEPA. The CBD also 

commented that the list of examples in 

proposed § 91.818(c)(2) suggesting the 

form of information an applicant could 

provide ‘‘oversimplifies the NEPA 

review process’’ for FAA. As stated at 

the beginning of this discussion, FAA 

agrees that the submission of 

information by an applicant (whether to 

support an EIS, EA, categorical 

exclusion, or other materials) does not 

itself satisfy NEPA requirements, which 

remains FAA’s duty. Further, FAA did 

not intend for the applicant’s 

submission, whatever form it may take, 

to represent the completion of the NEPA 

process. That process involves, where 

appropriate, public outreach, FAA’s 

objective evaluation of any information 

prepared by the applicant, as well as the 

exercise of independent judgment as to 

whether the NEPA process can be 

concluded with a finding of no 

significant impact, or whether it 

requires preparation of an 

environmental impact statement. 

The CBD concluded that, ‘‘Because 

Special Flight Authorizations for 

Supersonic Aircraft are major federal 

actions, an application for such 

authorization would trigger the need to 

prepare an EIS.’’ This conclusion is 

based on CBD’s reading of the 1970 

preamble that accompanied the 

adoption of the supersonic prohibition. 

FAA disagrees that the 1970 rule 

presumed that all supersonic flights 

were likely to create significant 

environmental impacts under NEPA and 

therefore require FAA to produce an 

EIS. While an application for a special 

flight authorization is a major Federal 

action subject to NEPA review, the 

specific facts associated with such an 

application determine what level of 

NEPA review is required. CBD 

presupposes a universal outcome 

regarding the proper level of NEPA 

review, disregarding the fact-specific 

nature of this determination. 

The proposed addition of the form of 

information to be submitted by 

applicants caused some commenters to 

misunderstand the FAA’s intent, and is 

an indication that the proposed 

regulatory changes were not helpful. 

Accordingly, FAA has removed 

proposed § 91.818(c)(2)(i) through (iii) 

from the final rule. This final rule 

revises the language in § 91.818(c)(2) to 

modernize it consistent with the 

recently revised CEQ regulations and 

the NEPA practice as it has developed 

since appendix B was first promulgated. 

The revised language clarifies that the 

information needed to support any 

particular application will be 

considered by FAA in its determination 

of whether the environmental impacts 

of the special flight authorization are 

significant. The provision of this 

information and the subsequent 

development of the appropriate level of 

environmental documentation will be 

carried out in accordance with the CEQ 

regulations and FAA procedures in the 

most recent version of FAA Order 

1050.1. 

C. Application Approval Process 

In proposed paragraph (a) of § 91.818, 

the FAA sought to locate into a moreuser friendly format the application 

requirements previously scattered 

throughout appendix B to part 91. 

Specifically, proposed § 91.818(a)(6) 

would require a ‘‘description of the 

flight area requested by the applicant, 

including any environment analysis 

required under paragraph (c) of this 

section.’’ This requirement was 

unchanged from appendix B. 

GE Aviation and Boom suggested that 

FAA adopt an expedited application 

approval process under certain 

circumstances. As a means to this 

expedited approval, both commenters 

suggested that a pre-approved set of 

parameters could form the basis for 

these approvals. GE Aviation suggested 

automatic approval when an applicant 

can show ‘‘that there have been no 

meaningful changes in the expected 

environmental impacts.’’ Noting what it 

considered a recognized lack of 

significant environmental impact 

(discussed above), Boom stated that a 

predefined set of parameters would 

provide certainty and reduce costs for 

manufacturers as well as reduce the 

burden on the FAA. 

FAA is not adopting the suggested 

expedited application approval process. 

First, the FAA does not find that preapproved circumstances can be 

determined, because there are several 

factors FAA considers for each 

application for supersonic testing, 

including performance of the particular 

aircraft. Second, the time-sensitive 

nature of environmental considerations 

can make prior determinations 

unreliable without reassessment at the 

time of each application, and could 

cause the FAA to fail in its 

environmental responsibilities. Under 

FAA policy, environmental assessments 

or EISs are not presumed valid 

indefinitely; after three years, a written 

reevaluation must be prepared. (See 

FAA Order 1050.1F.) However, FAA 

would accept previous environmental 

analyses of a proposed flight area as 

long as the material remains current and 

relevant, or has been updated by an 

applicant to meet those requirements. 

Third, FAA intends with this 

rulemaking to consider all applications 

uniformly. While the actual number of 

applications for authorization has been 

limited, FAA experience is that 

incomplete information submitted by an 

applicant has caused delays in the 

authorization approval process. 

While FAA is not changing the 

requirement in § 98.818(a)(6), FAA has 

revised it slightly from the proposed 

3786 Federal Register / Vol. 86, No. 10 / Friday, January 15, 2021 / Rules and Regulations 

rule to clarify that the requirement calls 

for information that supports analyses 

rather than the analyses themselves. 

D. Test Area Selections 

The term ‘‘designated test area’’ in 

appendix B created confusion for 

prospective applicants that interpreted 

the phrase to mean that designated test 

areas already exist, when they in fact do 

not. Rather, the term was used to refer 

to the proposed test area described 

(designated) in an application. FAA 

proposed eliminating this phrase and 

replacing it with § 91.818(a)(6) requiring 

an applicant to describe its requested 

test area in its application. Description 

of the proposed test area is one 

consideration in determining the 

acceptability of the application overall. 

Several commenters stated that the 

final rule should provide more 

flexibility for test area selections to 

allow more than one operator to use a 

test area, and to support the 

development of test areas outside of 

military operation areas (MOAs). GE 

Aviation, Aerospace Industries 

Association (AIA), General Aviation 

Manufacturer’s Association (GAMA), 

Supersonic Flight Alliance (SSFA), 

AeroTEC, and Boom suggested that FAA 

allow multiple manufacturers to use the 

same flight test area, as opposed to 

limiting areas to a single flight test 

campaign. Generally, the commenters 

stated that doing so would provide safer 

and more effective testing, and costsaving benefits to industry and FAA. 

Lockheed Martin Corporation 

(Lockheed) suggested establishing 

dedicated supersonic flight test areas. 

Additionally, Boom, SSFA, and 

AeroTEC expressed the general need for 

supersonic test areas outside of MOAs, 

citing concerns such as crowded 

airspace within MOAs and lack of 

available MOAs for civil flight testing. 

The Town of Milton, Massachusetts, 

stated that test sites should not be 

determined by industry applicants and 

urged FAA to limit test sites to MOAs. 

To support current industry 

development efforts, FAA provides 

supersonic flight test applicants with 

the broadest opportunity to request an 

appropriate flight test area, consistent 

with the applicable regulations and 

environmental impacts. FAA 

emphasizes that the regulation does not 

limit a flight test area to use by one 

applicant. As stated in the NPRM, 

nothing about the application process 

should be read to impede more than one 

prospective supersonic operator from 

seeking to use the same area or sharing 

the costs of the environmental studies 

that may be required (85 FR 30961, at 

30964). FAA does expect, however, that 

each operator intending to share the use 

of, or the costs associated with 

requesting, a test area will need to 

submit its own application with all of 

the information required for the 

processing of the application. In the 

case of a test area that has been 

previously approved under another 

application, the next applicant will 

need to submit information that 

includes a description of the (same) 

requested test area and the required 

environmental information. 

The final rule does not include 

suggestions from commenters for the 

FAA to establish ‘‘dedicated’’ test areas 

or a ‘‘civilian supersonic corridor’’ 

without proposed users or without a 

specific application. The regulation 

requires an applicant to show the 

probable impact of the applicant’s 

requested operations over a proposed 

test area. There can be no proper 

determination of any environmental 

impact on a test area without a proposal 

from an operator that includes the 

timing, duration, and expected noise 

impacts of the operator’s planned 

flights. A change in this fundamental 

nature of the process would require 

additional rulemaking and analysis. 

Moreover, the final rule, as is the case 

under the existing regulation, does not 

limit proposed test areas to MOAs. 

Several commenters disagreed with 

what they perceived to be FAA’s 

assumption that applicants will only 

test within existing MOAs. The 

commenters note that MOAs may not be 

suitable for civil supersonic testing and 

that applicants may develop their own 

supersonic test areas. The commenters’ 

concern might reflect a 

misunderstanding stemming from the 

Paperwork Reduction Act (PRA) 

statement that was published as part of 

the NPRM (see 84 FR 30965–66). FAA 

is required to estimate the information 

collection burden involved in 

complying with a regulation. FAA’s 

only historical data for special flight 

authorization came from applications 

proposing to use MOAs as test areas. 

FAA was thus unable to estimate any 

reliable information collection impact 

on future applicants for anything other 

than using a MOA that has underlying 

environmental data already available. 

But the use of MOAs as part of the 

required PRA statements supporting this 

rulemaking was not an indication that 

the rule prevents an applicant from 

choosing other areas. The choice of test 

area remains with each applicant after 

assessing its financial considerations 

and business needs. 

Finally, nothing in the regulation 

prevents a group of operators from 

sharing the costs of establishing a test 

area. As a matter of implementation, 

there must be a ‘‘first’’ applicant that 

submits all of the required information 

for FAA to make the first determination 

about an area based on the proposed 

flights. Subsequent applicants could use 

the same information, and include any 

differences that apply to the subsequent 

applicant, such as duration of the 

authorization, number of flights, or 

probable impact. The need for each 

operator individually to apply for and 

receive an authorization remains 

unchanged from the current 

requirements. No changes are being 

made to the requirement to describe the 

test areas based on these comments. 

E. Conducting Noise Testing During 

Supersonic Flight 

FAA proposed the measurement of 

noise characteristics in § 91.818(a)(8)(v) 

as an additional reason to conduct a 

supersonic flight. The new provision 

allows for the FAA to issue a special 

flight authorization for flights in excess 

of Mach 1 when measuring the noise 

characteristics of an aircraft for 

compliance with noise certification 

requirements, including conducting a 

noise test during supersonic flight. 

Appendix B addressed only flights 

necessary to comply with airworthiness 

certification testing, not noise tests. This 

change is forward-looking, as there are 

no standards for assessing noise at 

supersonic speed at this time. This 

limited expansion will facilitate noise 

certification testing for future 

supersonic aircraft when such noise 

standards are adopted. On April 13, 

2020, FAA issued an NPRM proposing 

noise certification standards for a 

certain class of new supersonic 

airplanes under part 36 (85 FR 20431), 

but those proposed standards are only 

for subsonic landing and takeoff. No 

special flight authorization would be 

needed to conduct the tests for subsonic 

noise compliance (landing and takeoff), 

as that noise is proposed to be measured 

in the same manner as subsonic aircraft. 

GE Aviation commented that the rule 

should address the full set of 

circumstances for requesting a special 

flight authorization, including 

requirements for testing airworthiness 

and operational capabilities. FAA notes 

that the proposed change allows an 

additional reason to request testing. The 

rule has always required applicants to 

specify the reason particular tests need 

to be conducted from the list provided 

in the regulation. FAA has not proposed 

to remove any of the general reasons 

from appendix B that an operator may 

have to test an airplane, including 

airworthiness testing. 

Federal Register / Vol. 86, No. 10 / Friday, January 15, 2021 / Rules and Regulations 3787 

Accordingly, the provision is adopted 

as proposed. 

F. Overocean Testing 

FAA proposed maintaining the 

requirement for an applicant to show 

why its test cannot be accomplished by 

flight over the ocean. The placement of 

this application requirement in 

appendix B often caused it to be 

overlooked as a prerequisite. The 

proposed rule placed the same 

overocean requirement in new 

§ 91.818(a)(9) with minor modification 

to state that an ‘‘applicant must indicate 

why its intended operation cannot be 

safely or properly accomplished over 

the ocean at a distance ensuring that no 

sonic boom overpressure reaches any 

land surface in the United States.’’ The 

addition of the last phrase aligns the 

rule with the requirement in § 91.817(b) 

that restricts supersonic operation of 

aircraft, including over the ocean, 

unless there are flight limitations to 

ensure that no sonic boom could impact 

the U.S. shoreline. 

1. Alternatives to Overocean Testing 

Commenters who are not in favor of 

the overocean testing requirement 

suggested alternatives. GE Aviation 

stated that there should be a provision 

and process to allow supersonic flight 

testing to move from over the ocean to 

over land and should involve various 

stages of modeling, along with testing 

and validation through flights over the 

ocean. Lockheed expressed appreciation 

for clarifying the applicability of the 

overocean provision, but suggested that 

an applicant provide FAA with the 

results of prior test modeling activity, 

which would then be used to shape an 

overwater validation test activity as a 

precursor to overland test operations. 

The SSFA and AeroTEC suggested that 

the collection of noise data over ground 

terrain would provide better quality 

data than over water. An individual 

commenter suggested adding the word 

‘‘efficiently’’ to the regulatory text of 

§ 91.818(a)(9), but did not provide any 

supporting explanation. An individual 

from Louisiana suggested that testing be 

done ‘‘over the Pacific Ocean or large 

bodies of water around 70 miles off the 

coast,’’ but provided no support for the 

specificity of this suggestion. 

FAA recognizes that there may be 

valid reasons why an applicant cannot 

conduct an overocean test properly. The 

provision in appendix B allowed for this 

possibility, as does the provision 

adopted in § 91.818(a)(9), which simply 

restates that an applicant needs to 

explain why overocean testing would 

not work. Furthermore, the rule does 

not restrict the submission of modeling 

data as support for an application if an 

applicant chooses to use it. FAA notes 

that if all supersonic operation is 

conducted over water outside U.S. 

airspace and at a distance that ensures 

no sonic boom effect on land, there is 

no need to even request a special flight 

authorization. It is only when 

supersonic flight over land is requested 

that an application need be submitted, 

in which case the applicant needs to 

explain why it cannot be accomplished 

over the ocean, in order to avoid 

unnecessary noise exposure on the 

ground. 

2. Economic Reasonableness 

Boom raised economic concerns with 

the overocean provision. Boom stated 

that FAA’s 1970s-era economic rationale 

for the prohibition on supersonic 

overland flight and application process 

for overland testing is not valid because 

it was based on a market assessment of 

supersonic aircraft that did not 

materialize. Boom also stated that the 

overocean requirement is not 

economically reasonable because testing 

supersonic aircraft over the ocean 

would require manufacturers located 

farther from the U.S. coastline to incur 

enormous expenses to set up additional 

test facilities with closer proximity to 

the ocean. Boom added that ‘‘for such 

an enormous expense, the public may 

be spared a few dozen half-second 

disturbances per year.’’ 

The FAA notes that the determination 

made in the 1970s that no level of sonic 

boom is acceptable over land still 

applies and is not based exclusively on 

economics. Furthermore, the FAA is not 

persuaded that a re-evaluation of the 

reasonableness of the overocean testing 

provisions is warranted simply because 

the anticipated size of the commercial 

fleet has not materialized. Neither Boom 

nor any other commenters provided any 

data or persuasive argument indicating 

that the overocean testing requirement 

has been a primary reason for, or even 

a contributing factor to, why the 

estimated commercial fleet of 

supersonic airplanes never materialized. 

Rather, Boom’s comment suggests that 

the requirement could pose a financial 

obstacle to Boom’s particular business 

plans, not that the regulation in general 

is economically unreasonable. 

3. Miscellaneous Overocean Provision 

Comments 

In addition to its economic 

reasonableness position, Boom stated 

that it ‘‘believes that a requirement to 

justify the safety benefits of conducting 

a supersonic operation over land could 

erode safety,’’ for which Boom 

hypothesized situations of production 

flight tests and the availability of 

diversion airports. Boom requested that 

FAA ‘‘remove the requirement to show 

that the test could not be safely 

accomplished over the ocean’’ in part 

because the showing ‘‘will never be 

decisive’’ and that a ‘‘rejection based on 

an inadequate safety justification could 

lead to a tragic loss of life.’’ 

FAA disagrees with Boom that there 

is no economic or other justifiable basis 

for the requirement. The provision for 

overocean testing reinforces the 

principal purpose underlying appendix 

B to part 91, to protect humans and the 

environment in the United States from 

the effects of sonic booms. The 

appendix establishes as a ‘‘default’’ the 

position that supersonic flight testing be 

conducted over the ocean rather than on 

land where sonic booms would impact 

the surface environment. The appendix 

and this rule provide applicants with an 

avenue to conduct supersonic test 

flights over land if they are able to 

explain why testing cannot be safely or 

properly conducted over the ocean. 

Three other commenters submitted 

suggestions to clarify the overocean 

provision. AIA and GAMA suggested 

that FAA clarify that a special flight 

authorization is not required if a test can 

be performed over the ocean at a 

distance ensuring that no sonic boom 

overpressure reaches any land surface in 

the United States. GE Aviation made the 

same comment but used ‘‘application’’ 

rather than ‘‘authorization.’’ As stated 

previously, no special flight 

authorization is required if the 

supersonic portion of any flight is 

conducted over the ocean at a distance 

ensuring that no sonic boom will reach 

land in the United States. The Town of 

Milton suggested that FAA require 

overocean supersonic testing in such a 

manner that no sonic boom 

overpressure reaches land before any 

testing over land is authorized. 

However, FAA recognizes that there 

may be situations where testing may not 

be safely or properly accomplished over 

the ocean, such as there being no 

effective way to measure noise on flights 

over water, including any noise impact 

that might be discernable on land. 

For the reasons discussed, FAA 

adopts the overocean testing provision 

as proposed. 

G. Operation Outside a Test Area 

FAA proposed a new § 91.818(b) to 

maintain the provisions in section 2(b) 

of appendix B that allow an applicant to 

request supersonic non-test flights 

outside of a test area. The prerequisites 

for this supersonic operation are 

considerable and are discussed below. 

3788 Federal Register / Vol. 86, No. 10 / Friday, January 15, 2021 / Rules and Regulations 

6The inclusion of NEPA language and FAA Order 

1050.1F in Boom’s comment on measurable sonic 

boom overpressure were addressed above in the 

NEPA comment disposition. 

1. Foreseeable Operating Conditions 

Outside of a Test Area 

Proposed § 91.818(b)(3) would 

maintain the requirement of appendix B 

section 2(b) that a supersonic non-test 

flight applicant show—as part of a prior 

test conducted inside a test area—that 

‘‘[t]he conditions and limitations 

determined by that test present all 

foreseeable operating conditions and are 

effective on all flights conducted under 

an authorization.’’ 

Aerion, GE Aviation, AIA, and GAMA 

stated that this requirement is 

unreasonable because it is not possible 

to predict all conditions under which an 

aircraft may operate. Aerion noted that 

the appendix B requirement originated 

before reliable sonic boom prediction 

technologies existed. All four 

commenters suggested replacing 

§ 91.818(b)(3) with a standard based on 

currently available sonic boom 

prediction and control technology. 

In general, the phrases ‘‘conditions 

and limitations’’ and ‘‘operating 

conditions,’’ as they are commonly 

applied to any flight authorization, do 

not require operators or FAA to predict 

every conceivable operating condition 

that may occur. FAA clarifies that ‘‘all 

foreseeable operating conditions’’ refers 

to the reasonable expected conditions 

under which the aircraft would be 

operated, and is not meant to require a 

prediction of every possible condition. 

2. Measurable Sonic Boom Overpressure 

Outside of a Test Area 

The application for operation outside 

a test area also includes a requirement 

that allows for such flights when it 

conservatively can be shown that ‘‘no 

measurable sonic boom overpressure’’ 

will reach the surface. FAA proposed to 

retain this provision as § 91.818(b)(2). 

FAA stresses that the requirement to 

show ‘‘no measureable sonic boom 

overpressure’’ applies only to flights 

outside of a test area, and not as an 

application for operations in a requested 

test area under proposed 

§ 91.818(a)(8)(iv). 

Several commenters, including 

prospective supersonic airframe and 

engine manufacturers, stated that the 

provision should be eliminated because 

it is overly restrictive and outdated. 

Aerion stated that the provision ‘‘was 

originally adopted in the 1970s out of an 

abundance of caution based on the 

relatively undeveloped state of sonic 

boom technology at that time.’’ Aerion 

added that sonic boom prediction and 

control technology has advanced to the 

point where it is possible to make 

accurate predictions of the location and 

intensity of sonic booms. Aerion and GE 

Aviation noted that the provision does 

not recognize the possibility for a sonic 

boom to be produced that is barely 

noticeable on the ground, but can still 

be detected by scientific measurement, 

such as a small pressure disturbance. 

SSFA and AeroTEC referenced NASA’s 

supersonic flight tests that show 

overpressure wave remnants at ground 

level that do not have the sharp-edged 

characteristic of a sonic boom. Boom 

indicated that the standard (unchanged 

from appendix B) ‘‘goes far beyond what 

is required under the National 

Environmental Policy Act, as allowance 

of measurable overpressure is not 

necessarily a major Federal action 

‘significantly affecting the quality of the 

human environment’ as interpreted 

under agency guidance under Order 

1050.1F.’’ 6

Other commenters also supported the 

elimination of the provision. Both AIA 

and GAMA read the phrase ‘‘no 

measurable sonic boom’’ to be an 

absolute prohibition on supersonic 

operations, finding it overly restrictive 

and something ‘‘that an applicant would 

be unable to guarantee during a test 

flight.’’ The Town of Milton, 

Massachusetts, stated that FAA should 

remove § 91.818(b) in its entirety 

because no aircraft can satisfy the ‘‘no 

overpressure’’ provision, adding that it 

should be replaced by a new regulation 

only after supersonic testing 

demonstrates no measurable sonic boom 

overpressure. 

New Frontier Aerospace is the only 

commenter that supported retaining the 

provision, stating that it foresees the 

need to apply for the § 91.818(b) 

operating allowance in order to conduct 

extensive testing of an aircraft, and that 

the removal of this provision could have 

a serious impact on its aircraft that is 

still in development. 

In the NPRM, FAA stated that it is not 

seeking to propose alternatives to this 

provision as a means to approve routine 

civil supersonic flight, but simply seeks 

comment on whether the provision as 

written retains any current value. 

However, several commenters submitted 

alternatives. New Frontier Aerospace 

suggested that in place of ‘‘no 

measureable sonic boom’’ it would be 

beneficial to provide a specific numeric 

limitation for overpressure or noise 

levels. Aerion stated that the provision 

should be replaced with a standard 

based on currently available sonic boom 

prediction control technology. Other 

commenters (GE Aviation, AIA, and 

GAMA) suggested a more appropriate 

standard than ‘‘no measurable sonic 

boom overpressure’’ would be to ensure 

that no significant impacts on the 

environment or communities result 

from granting an authorization. 

The scope of the provision, both as it 

appears in the appendix and in the 

proposed rule, appears to be a 

continued source of confusion for some 

commenters. The section in the 

appendix that was proposed as 

§ 91.818(b) sets the ‘‘no measurable 

sonic boom overpressure’’ criterion only 

for civil supersonic flights that would 

take place outside a test area. Several 

commenters seemed to presume 

inaccurately that this standard would be 

applied to all applications for special 

flight authorizations, even those that 

would be within a test area. The 

requirement to show conservatively that 

no measurable sonic boom overpressure 

reaches the surface does not apply to 

test flights that are authorized to be 

conducted in an approved test area. An 

operator with an authorization to flight 

test at supersonic speeds for one of the 

permissible purposes set forth in 

§ 91.818(a)(8) may potentially (subject to 

the conditions and limitations of its 

authorization) operate a flight that 

results in sonic boom overpressures 

reaching the surface inside the test area, 

as expected. Accordingly, FAA 

disagrees that the standard is overly 

restrictive. It restricts sonic boom 

overpressures from reaching the surface 

when flights are conducted outside of 

test areas, consistent with the overall 

intent of the regulations to prohibit 

routine or non-test supersonic flights 

over land. FAA emphasizes, though, 

that in accordance with § 91.818(a)(7) 

no sonic boom overpressures are 

allowed to reach the surface outside of 

the test area. Moreover, as required by 

§ 91.818(a)(6) and (c), the operator must 

provide FAA with the information 

necessary for the agency to assess the 

environmental impacts resulting from 

such flights. 

Further, commenters’ 

recommendations either to replace the 

‘‘no measurable sonic boom 

overpressure’’ standard with a specific 

perceived decibel level or to remove it 

entirely go beyond the scope of what 

FAA proposed and the intent of this 

rulemaking, which is to modernize the 

administrative process for applying for 

the special flight authorization. The 

noise levels recommended by some 

commenters are relative to existing 

noise levels applicable to subsonic 

aircraft and would not be appropriate 

for measuring noise levels of aircraft 

flying at supersonic speeds. There are 

no accepted means of measuring 

supersonic noise, nor are there any 

Federal Register / Vol. 86, No. 10 / Friday, January 15, 2021 / Rules and Regulations 3789 

noise limits that have been deemed 

acceptable as a community standard, 

whether expressed in decibels or as 

sonic overpressure. Establishing 

supersonic noise levels for operations 

outside a test area would need to be 

accomplished in a future rulemaking 

and supported by appropriate data. 

None of the commenters suggested 

anything more than a future expectation 

that non-test flights might need to occur. 

FAA fully expects that, at some point, 

flights outside a test area would need to 

occur. But FAA does not have a 

reasonable expectation of what might be 

needed, since there have been no 

application for flights within a test area 

designated by an applicant and 

approved by FAA (where prior 

measurements would have to occur), 

nor applications that describe a test area 

that may need to be exceeded. After 

more testing occurs, and development 

has progressed to require such flights, 

more modern standards for measuring 

supersonic noise events and their 

impacts may have developed as well. At 

that time, the industry and FAA will be 

better positioned to suggest supportable 

changes to the rule on flights outside a 

test area. For these reasons, the 

suggestions that compare computer 

simulations of unrealized aircraft to the 

noise of the current subsonic fleet are 

not considered a sufficient basis to 

change the standard for flights outside 

a test area at this time, and no such 

changes were proposed. 

Eliminating the ‘‘no measurable sonic 

boom overpressure’’ regulatory text is 

also not appropriate in this rulemaking. 

The provision was adopted in the 1970s 

as a kind of relief valve to the 

prohibition in § 91.817, based on the 

principle that a supersonic flight with 

no measureable overpressure (shown 

during previous flights in a valid test 

area) should not summarily be 

prohibited. In that sense, the 

circumstances have not changed, and 

there is no current data to support either 

eliminating the rule or determining a 

level of acceptable measurable sonic 

boom overpressure other than zero, 

which would be necessary before flights 

outside a test area could be considered. 

FAA will continue to review advances 

in technology that affect noise values 

produced by supersonic airplanes and 

the evaluation of those noise events. 

Accordingly, as the provision represents 

a safeguard from unknown sonic boom 

effects that may be unrelated to aircraft 

testing, no change to the rule is 

supported by the comments, and 

§ 91.818(b) is adopted as proposed. 

H. Necessary To Protect or Enhance the 

Environment 

FAA proposed § 91.818(c)(1) to 

provide that an authorization will not be 

granted ‘‘if the Administrator finds that 

such action is necessary to protect or 

enhance the environment.’’ This 

provision maintains the requirement 

stated in section 1(d) of appendix B. 

Commenters (GE Aviation, GAMA, and 

AIA) generally opposed this provision 

and read it to suggest that the 

Administrator would be required or able 

to deny an authorization because 

approving such flights would not lead to 

an enhancement of the environment. GE 

Aviation suggested that § 91.818(c)(1) 

instead state that an application would 

not be denied if an applicant 

demonstrates that the flights would not 

have a significant impact on the 

environment. 

FAA notes that this language has been 

in the regulation since its adoption in 

the 1970s. Under this provision, the 

Administrator may consider adverse 

environmental impacts that would come 

from granting any particular flight 

authorization. The provision does not 

create a presumption that any particular 

application and grant would have to 

demonstrate a positive impact on the 

environment, as suggested by 

commenters. Commenters provided no 

indication that the authorizations that 

have been approved thus far have 

included or required any such 

demonstration of environmental 

enhancement. Therefore, the provision 

is adopted as proposed. 

I. Using Software for Predictive Analysis 

Commenters provided general 

suggestions that the rule should 

specifically allow applicants to use 

software programs for predictive 

analyses in applications for special 

flight authorizations. In response, FAA 

notes that nothing in the existing or 

proposed rule prohibits an applicant 

from using such prediction and control 

technologies to supplement its 

application for a special flight 

authorization. Further, FAA supports 

applicants using existing software tools 

to predict the location and intensity of 

sonic boom ground impacts as 

supporting data in their test flight 

authorization applications, as they are 

available and apply to an applicant’s 

specific circumstances. No change in 

the rule is made based on these 

comments. 

J. NAS Concerns 

AOPA expressed concerns with the 

safe integration of supersonic aircraft 

into the National Airspace System 

(NAS), particularly with ‘‘see and 

avoid.’’ AOPA also commented that 

FAA should carefully review any 

applications for overland flight below 

18,000 feet altitude, and conduct a 

safety risk assessment of how 

supersonic airplane design may impact 

speed restrictions below 10,000 feet and 

the effectiveness of sense and avoid 

systems. 

Most of AOPA’s considerations center 

around anticipation of eventual routine 

operation of supersonic aircraft in the 

same airspace as smaller, slower 

airplanes. This rule does not grant 

authorizations to exceed Mach 1 in 

airspace where the flights would 

negatively impact the safety of the NAS 

or persons on the ground without 

notice. This rule is limited to the 

application for an authorization to 

exceed Mach 1 during test flights over 

a specific area to be determined in each 

application. The impact on routine 

aviation operations would be a factor in 

analyzing the proposed flight area. 

Many of the considerations expressed 

by AOPA speak to characteristics of 

individual airplane designs that would 

not be available for evaluation before 

the aircraft actually fly or are presented 

for certification. No change to the 

proposed regulation was suggested in 

this comment. 

K. Miscellaneous Comments 

The Information Technology and 

Innovation Foundation suggested that 

FAA lift the supersonic ban based on 

speed and replace it with a set of noise 

standards to provide clarity for 

manufacturers that are developing 

supersonic airplanes. FAA notes that 

the NPRM specifically mentioned that 

the proposed revisions did not affect the 

general prohibition on supersonic flight. 

As also noted, FAA took the first step 

in developing noise standards for new 

supersonic airplanes in its April 2020 

NPRM proposing changes to 14 CFR 

part 36. The comment is considered 

beyond the scope of this rulemaking. 

IV. Changes From the Proposed Rule 

In the final rule, FAA made the 

following changes from the proposed 

rule: 

1. Section 91.818(a)(6) was revised to 

say ‘‘environmental information’’ rather 

than ‘‘environmental analysis’’ to avoid 

confusion about the nature of the 

material being submitted. 

2. In § 91.818(c)(2), the subordinate 

paragraphs describing the types of 

information that might be submitted by 

an applicant were removed to prevent 

confusion over what information and 

what format would be acceptable. Other 

language in the paragraph was added to 

3790 Federal Register / Vol. 86, No. 10 / Friday, January 15, 2021 / Rules and Regulations 

clarify FAA’s responsibilities under 

NEPA, as noted above in the disposition 

of comments. 

V. Regulatory Notices and Analyses 

Changes to Federal regulations must 

undergo several economic analyses. 

First, Executive Orders 12866 and 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. In addition, DOT 

rulemaking procedures in subpart B of 

49 CFR part 5 instruct DOT agencies to 

issue a regulation upon a reasoned 

determination that benefits exceed 

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 (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 FAA’s analysis of the 

economic impacts of this final rule. 

In conducting these analyses, FAA 

has determined that this final 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) is not 

‘‘significant’’ as defined in DOT’s 

Regulatory Policies and Procedures; (4) 

will not have a significant economic 

impact on a substantial number of small 

entities; (5) will not create unnecessary 

obstacles to the foreign commerce of the 

United States; and (6) will not impose 

an unfunded mandate on State, local, or 

tribal governments, or on the private 

sector by exceeding the threshold 

identified above. These analyses are 

summarized below. 

A. Regulatory Evaluation 

This rule amends the administrative 

requirements for a special flight 

authorization originally published in 

appendix B to 14 CFR part 91, 

Authorizations to exceed Mach 1 

(§ 91.817). This rule supports 

innovation in the development of new 

civil supersonic aircraft by streamlining 

existing regulations. This rule 

streamlines the application procedure 

for special flight authorizations by 

clarifying the information needed for 

submission, and specifying the program 

office within FAA that processes the 

applications. This rule sets forth the 

application criteria in a more userfriendly format. FAA is adopting this 

rule largely as it was proposed, with 

some minor changes to the regulatory 

text, as discussed in Section IV and the 

accompanying preamble discussion. 

As noted above, FAA provides a new 

reason for part 91 special flight 

authorizations—to measure the noise 

characteristics of an aircraft for 

compliance with noise certification 

requirements, including conducting 

noise testing during supersonic flight. 

This provision is beneficial as it 

anticipates the addition of future part 36 

noise certification requirements for 

supersonic aircraft. Including the 

provision now will ensure the 

availability of testing as an option and 

that it is not overlooked when the part 

36 standards are established. 

Since there are no substantive 

changes to the requirements for these 

special flight authorizations, this rule 

would not have additional costs. The 

rule provides increased clarity for 

applicants and may reduce the number 

of follow-up requests for additional 

information between FAA and 

applicants. 

B. Regulatory Flexibility Determination 

The Regulatory Flexibility Act of 1980 

(Pub. L. 96–354) (RFA) establishes as a 

principle of regulatory issuance that 

agencies shall endeavor, consistent with 

the objectives 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 this principle, 

agencies are required to solicit and 

consider flexible regulatory proposals 

and to explain the rationale for their 

actions to assure such proposals are 

given serious consideration. The RFA 

covers a wide-range of small entities, 

including small businesses, not-forprofit organizations, and small 

governmental jurisdictions. 

Agencies must perform a review to 

determine whether a 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 

RFA. 

However, if an agency determines that 

a rule is not expected to have a 

significant economic impact on a 

substantial number of small entities, 

section 605(b) of the 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. 

As noted in the Regulatory Evaluation 

section, this final rule will not have 

additional costs. Therefore, this final 

rule would not have a significant 

economic impact on a substantial 

number of firms. Therefore, as provided 

in section 605(b), the head of FAA 

certifies that this rulemaking would not 

result in a significant economic impact 

on a substantial number of small 

entities. 

C. 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, 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. 

FAA has assessed the potential effect 

of this final rule and has determined 

that it will have a legitimate domestic 

objective, in that it will provide 

increased clarity and information to 

applicants as to the requirements for 

special flight authorizations to test 

supersonic aircraft. This rule will not 

operate in a manner as to affect foreign 

trade directly and, therefore, will have 

little or no effect on foreign trade. 

D. 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 (in 

1995 dollars) in any one year by State, 

local, and tribal governments, in the 

aggregate, or by the private sector; such 

Federal Register / Vol. 86, No. 10 / Friday, January 15, 2021 / Rules and Regulations 3791 

a mandate is deemed to be a ‘‘significant 

regulatory action.’’ FAA currently uses 

an inflation-adjusted value of $155.0 

million in lieu of $100 million. 

This rule does not contain such a 

mandate. Therefore, the requirements of 

Title II of the Act do not apply. 

E. Paperwork Reduction Act 

The Paperwork Reduction Act of 1995 

(44 U.S.C. 3507(d)) requires that FAA 

consider the impact of paperwork and 

other information collection burdens 

imposed on the public. According to the 

1995 amendments to the Paperwork 

Reduction Act (5 CFR 1320.8(b)(2)(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 Office of Management 

and Budget (OMB) control number. 

This final rule contains the following 

amendments to the existing information 

collection requirements for OMB 

Control Number 2120–0005. As 

discussed in the NPRM, the original 

estimated annual number of responses 

(applications) was high, 20 annually, 

and the annual time burden (hours per 

response) was low, 14 hours. The 

changes to both the number of annual 

responses and the hours per request is 

not a result of any of the changes 

described in this rulemaking, but 

reflects a change in the understanding of 

both the number of applicants expected, 

and the requirements for environmental 

information between the original 

collection request and now. With 

limited PRA comment responses, FAA 

submits the following changes due to 

agency discretion/experience of this 

information collection to OMB for its 

review and approval. 

Summary: Authorization to exceed 

Mach 1 over land. 

Use: To authorize supersonic airplane 

test flights at approved sites. 

Respondents (including number of): 

Three producers of civil supersonic 

airplanes. 

Frequency: Three applications in a 

three-year period. 

Annual Burden Estimate: One 

application annually. 

FAA estimates fully burdened labor 

cost to be about $200 per hour, making 

the annual cost $200 × 40 = $8,000. This 

estimate is based on the assumption that 

an applicant will not need to develop a 

new environmental document for the 

Administrator’s NEPA determination. 

FAA assumes that applicants would 

qualify to use airspace in U.S. military 

test ranges where supersonic flights 

already occur and a NEPA document 

already exists. 

Individuals and organizations may 

send comments on the information 

collection requirement to the address 

listed in the ADDRESSES section at the 

beginning of this preamble by March 16, 

2021. 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 20503. 

F. International Compatibility 

In keeping with U.S. obligations 

under the Convention on International 

Civil Aviation, it is FAA policy to 

conform to International Civil Aviation 

Organization (ICAO) Standards and 

Recommended Practices to the 

maximum extent practicable. FAA has 

reviewed the corresponding ICAO 

Standards and Recommended Practices 

and has identified no differences with 

these regulations. 

G. Environmental Analysis 

FAA Order 1050.1F 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. 

FAA has determined that this 

rulemaking action updating the 

application process for special flight 

authorizations qualifies for the 

categorical exclusion identified in 

paragraph 5–6.6 and involves no 

extraordinary circumstances. 

VI. Executive Order Determinations 

A. Executive Order 13132, Federalism 

FAA has analyzed this final rule 

under the principles and criteria of 

Executive Order 13132, Federalism. The 

agency determined that this action will 

not have a substantial direct effect on 

the States, or the relationship between 

the Federal Government and the States, 

or on the distribution of power and 

responsibilities among the various 

levels of government, and, therefore, 

does not have federalism implications. 

B. Executive Order 13211, Regulations 

That Significantly Affect Energy Supply, 

Distribution, or Use 

FAA analyzed this final rule under 

Executive Order 13211, Actions 

Concerning Regulations that 

Significantly Affect Energy Supply, 

Distribution, or Use (May 18, 2001). 

FAA has determined that it is not a 

‘‘significant energy action’’ under the 

executive order and it is not likely to 

have a significant adverse effect on the 

supply, distribution, or use of energy. 

C. Executive Order 13609, International 

Cooperation 

Executive Order 13609, Promoting 

International Regulatory Cooperation, 

promotes international regulatory 

cooperation to meet shared challenges 

involving health, safety, labor, security, 

environmental, and other issues and to 

reduce, eliminate, or prevent 

unnecessary differences in regulatory 

requirements. FAA has analyzed this 

action under the policies and agency 

responsibilities of Executive Order 

13609, and has determined that this 

action will not have an effect on 

international regulatory cooperation. 

D. Executive Order 13771, Reducing 

Regulation and Controlling Regulatory 

Costs 

This final rule is considered an E.O. 

13771 deregulatory action. Details on 

the streamlining effects of this rule can 

be found in the rule’s regulatory 

evaluation. 

VII. How To Obtain Additional 

Information 

A. Rulemaking Documents 

An electronic copy of a rulemaking 

document may be obtained by using the 

internet— 

1. Search the Federal eRulemaking 

Portal (http://www.regulations.gov); 

2. Visit FAA’s Regulations and 

Policies web page at http://

www.faa.gov/regulations_policies/ or 

3. Access the Government Printing 

Office’s web page at 

http://www.gpo.gov/fdsys/. 

Copies may also be obtained by 

sending a request (identified by notice, 

amendment, or docket number of this 

rulemaking) to the Federal Aviation 

Administration, Office of Rulemaking, 

ARM–1, 800 Independence Avenue SW, 

Washington, DC 20591, or by calling 

(202) 267–9680. 

B. Comments Submitted to the Docket 

Comments received may be viewed by 

going to http://www.regulations.gov and 

following the online instructions to 

search the docket number for this 

action. Anyone is able to search the 

electronic form of all comments 

received into any of FAA’s dockets by 

the name of the individual submitting 

the comment (or signing the comment, 

if submitted on behalf of an association, 

business, labor union, etc.). 

C. Small Business Regulatory 

Enforcement Fairness Act 

The Small Business Regulatory 

Enforcement Fairness Act (SBREFA) of 

1996 requires FAA to comply with 

small entity requests for information or 

3792 Federal Register / Vol. 86, No. 10 / Friday, January 15, 2021 / Rules and Regulations 

advice about compliance with statutes 

and regulations within its jurisdiction. 

A small entity with questions regarding 

this document, may contact its local 

FAA official, or the person listed under 

the FOR FURTHER INFORMATION CONTACT

heading at the beginning of the 

preamble. To find out more about 

SBREFA on the internet, visit http://

www.faa.gov/regulations_policies/ 

rulemaking/sbre_act/. 

List of Subjects in 14 CFR Part 91 

Aircraft, Aviation safety, Noise 

control, Reporting and recordkeeping 

requirements. 

The Amendment 

In consideration of the foregoing, the 

Federal Aviation Administration 

amends chapter I of title 14, Code of 

Federal Regulations as follows: 

PART 91—GENERAL OPERATING AND 

FLIGHT RULES 

■ 1. The authority citation for Part 91 

continues to read as follows: 

Authority: 49 U.S.C. 106(f), 106(g), 40101, 

40103, 40105, 40113, 40120, 44101, 44111, 

44701, 44704, 44709, 44711, 44712, 44715, 

44716, 44717, 44722, 46306, 46315, 46316, 

46504, 46506–46507, 47122, 47508, 47528– 

47531, 47534, Pub. L. 114–190, 130 Stat. 615 

(49 U.S.C. 44703 note); articles 12 and 29 of 

the Convention on International Civil 

Aviation (61 Stat. 1180), (126 Stat. 11). 

§ 91.817 [Amended] 

■ 2. In § 91.817(a) and (b)(2), remove the 

words ‘‘under appendix B of this part’’ 

and add in their place the words ‘‘in 

accordance with § 91.818’’. 

■ 3. Add § 91.818 to read as follows: 

§ 91.818 Special flight authorization to 

exceed Mach 1. 

For all civil aircraft, any operation 

that exceeds Mach 1 may be conducted 

only in accordance with a special flight 

authorization issued to an operator in 

accordance with the requirements of 

this section. 

(a) Application. Application for a 

special flight authorization to exceed 

Mach 1 must be made to the FAA Office 

of Environment and Energy for 

consideration by the Administrator. 

Each application must include: 

(1) The name of the operator; 

(2) The number and model(s) of the 

aircraft to be operated; 

(3) The number of proposed flights; 

(4) The date range during which the 

flight(s) would be conducted; 

(5) The time of day the flight(s) would 

be conducted. Proposed night 

operations may require further 

justification for their necessity; 

(6) A description of the flight area 

requested by the applicant, including 

any environmental information required 

to be submitted pursuant to paragraph 

(c) of this section; 

(7) All conditions and limitations on 

the flight(s) that will ensure that no 

measurable sonic boom overpressure 

will reach the surface outside of the 

proposed flight area; and 

(8) The reason(s) that operation at a 

speed greater than Mach 1 is necessary. 

A special flight authorization to exceed 

Mach 1 may be granted only for 

operations that are intended to: 

(i) Show compliance with 

airworthiness requirements; 

(ii) Determine the sonic boom 

characteristics of an aircraft; 

(iii) Establish a means of reducing or 

eliminating the effects of sonic boom, 

including flight profiles and special 

features of an aircraft; 

(iv) Demonstrate the conditions and 

limitations under which speeds in 

excess of Mach 1 will not cause a 

measurable sonic boom overpressure to 

reach the surface; or 

(v) Measure the noise characteristics 

of an aircraft to demonstrate compliance 

with noise requirements imposed under 

this chapter, or to determine the limits 

for operation in accordance with 

§ 91.817(b). 

(9) For any purpose listed in 

paragraph (a)(8) of this section, each 

applicant must indicate why its 

intended operation cannot be safely or 

properly accomplished over the ocean at 

a distance ensuring that no sonic boom 

overpressure reaches any land surface in 

the United States. 

(b) Operation outside a test area. An 

applicant may apply for an 

authorization to conduct flights outside 

a test area under certain conditions and 

limitations upon a conservative showing 

that: 

(1) Flight(s) within a test area have 

been conducted in accordance with an 

authorization issued for the purpose 

specified in paragraph (a)(8)(iv) of this 

section; 

(2) The results of the flight test(s) 

required by paragraph (b)(1) of this 

section demonstrate that a speed in 

excess of Mach 1 does not cause a 

measurable sonic boom overpressure to 

reach the surface; and 

(3) The conditions and limitations 

determined by the test(s) represent all 

foreseeable operating conditions and are 

effective on all flights conducted under 

an authorization. 

(c) Environmental findings. (1) No 

special flight authorization will be 

granted if the Administrator finds that 

such action is necessary to protect or 

enhance the environment. 

(2) The Administrator is required to 

consider the potential environmental 

impacts resulting from the issuance of 

an authorization for a particular flight 

area pursuant to the National 

Environmental Policy Act of 1969 

(NEPA) (42 U.S.C 4321 et seq.), all 

applicable regulations implementing 

NEPA, and related Executive orders and 

guidance. Accordingly, each applicant 

must provide information that 

sufficiently describes the potential 

environmental impact of any flight in 

excess of Mach 1, including the effect of 

a sonic boom reaching the surface in the 

proposed flight area, to enable the FAA 

to determine whether such impacts are 

significant within the meaning of NEPA. 

(d) Issuance. An authorization to 

operate a civil aircraft in excess of Mach 

1 may be issued only after an applicant 

has submitted the information described 

in this section and the Administrator 

has taken the required action regarding 

the environmental findings described in 

paragraph (c) of this section. 

(e) Duration. (1) An authorization to 

exceed Mach 1 will be granted for the 

time the Administrator determines 

necessary to conduct the flights for the 

described purposes. 

(2) An authorization to exceed Mach 

1 is effective until it expires or is 

surrendered. 

(3) An authorization to exceed Mach 

1 may be terminated, suspended, or 

amended by the Administrator at any 

time the Administrator finds that such 

action is necessary to protect the 

environment. 

(4) The holder of an authorization to 

exceed Mach 1 may request 

reconsideration of a termination, 

amendment, or suspension issued under 

paragraph (e)(3) of this section within 

30 days of notice of the action. Failure 

to request reconsideration and provide 

information why the Administrator’s 

action is not appropriate will result in 

permanent termination of the 

authorization. 

(5) Findings made by and actions 

taken by the Administrator under this 

section do not affect any certificate 

issued under chapter 447 of Title 49 of 

the United States Code. 

Appendix B to Part 91—[Removed and 

Reserved] 

■ 4. Remove and reserve appendix B to 

part 91. 

Issued in Washington, DC, under the 

authority of 49 U.S.C. 106(f), 44701(a)(5), and 

44715, on January 4, 2021. 

Steve Dickson, 

Administrator. 

[FR Doc. 2021–00113 Filed 1–14–21; 8:45 am] 

BILLING CODE 4910–13–P