Document ID: FAA-2022-0241-0001
Agency: faa
Document Type: Proposed Rule
Title: Airplane Fuel Efficiency Certification
Posted Date: 2022-06-15T04:00Z

[Federal Register Volume 87, Number 115 (Wednesday, June 15, 2022)]
[Proposed Rules]
[Pages 36076-36091]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2022-11556]

 ========================================================================
 Proposed Rules
                                                 Federal Register
 ________________________________________________________________________
 
 This section of the FEDERAL REGISTER contains notices to the public of 
 the proposed issuance of rules and regulations. The purpose of these 
 notices is to give interested persons an opportunity to participate in 
 the rule making prior to the adoption of the final rules.
 
 ========================================================================
 

  Federal Register / Vol. 87, No. 115 / Wednesday, June 15, 2022 / 
Proposed Rules  

[[Page 36076]]

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Parts 21, 38, 121, and 125

[Docket No.: FAA-2022-0241; Notice No. 22-03]
RIN 2120-AL54

Airplane Fuel Efficiency Certification

AGENCY: Federal Aviation Administration (FAA), Transportation (DOT).

ACTION: Notice of proposed rulemaking (NPRM).

-----------------------------------------------------------------------

SUMMARY: This action proposes fuel efficiency requirements for 
certification of certain airplanes. These certification requirements 
would implement the emissions standards adopted by the Environmental 
Protection Agency, allowing manufacturers to certificate their aircraft 
for fuel efficiency in the United States, and fulfilling the statutory 
obligations of the FAA under the Clean Air Act.

DATES: Send comments on or before August 15, 2022.

ADDRESSES: Send comments identified by docket number FAA-2022-0241 
using any of the following methods:
     Federal eRulemaking Portal: Go to 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 (DOT), 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: In accordance with 5 U.S.C. 553(c), DOT solicits comments 
from the public to better inform its rulemaking process. DOT posts 
these comments, without edit, including any personal information the 
commenter provides, to www.regulations.gov, as described in the system 
of records notice (DOT/ALL-14 FDMS), which can be reviewed at 
www.dot.gov/privacy.
    Docket: Background documents or comments received may be read at 
www.regulations.gov at any time. Follow the online instructions for 
accessing the docket or go to the 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 action, contact Ralph Iovinelli, Office of Policy, International 
Affairs & Environment, Emissions Division (AEE-300), Federal Aviation 
Administration, 800 Independence Avenue SW, Washington, DC 20591; 
telephone 202-267-3566; email [email protected].

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.
    The authority to insure compliance with aviation emission standards 
adopted by the United States Environmental Protection Agency (EPA) is 
granted to the Secretary of Transportation in the Clean Air Act 
Amendments of 1970 (CAA), title 42 of the United States Code (U.S.C.), 
Chapter 85, Subchapter II, part B, Section 7572. Further, 49 CFR 
1.83(c) delegates to the FAA Administrator the authority to ``Carry out 
the functions vested in the Secretary by part B of title II of the 
CAA.''
    This rulemaking proposes regulations to insure compliance with the 
standards adopted by the EPA under the CAA in 40 CFR part 1030 to 
control the emission of certain greenhouse gas emissions from 
airplanes. This rulemaking is issued under the authority described in 
42 U.S.C. 7572 and 49 CFR 1.83(c).

I. Background

    As a signatory State to the International Civil Aviation 
Organization's (ICAO) Chicago Convention, the United States must 
establish minimum standards consistent with ICAO or file a difference. 
The Committee on Aviation Environmental Protection (CAEP) is a 
technical committee of ICAO that assists in formulating ICAO policy and 
in adopting Standards and Recommended Practices related to aircraft 
noise and emissions. The FAA represents the United States on CAEP, 
attending annual Steering Group meetings and CAEP triennial meetings, 
and contributing technical expertise to CAEP's many working groups. The 
EPA serves as an advisor to the U.S. member of CAEP at the annual and 
triennial meetings, and contributes technical expertise to the FAA and 
CAEP's working groups on aviation emissions, pollution control 
technology, and environmental policy. Within CAEP, the FAA assists and 
advises the EPA on aviation-specific environmental issues, airplane and 
engine technologies, and airworthiness certification matters.
    In 2009, the ICAO Council and its Group on International Aviation 
and Climate Change (GIACC) developed a ``Programme of Action'' to limit 
or reduce the impact of aviation on the climate. The program's ``basket 
of measures'' included the reduction of the carbon footprint of 
international civil aviation, beginning with the development of a 
technology-based certification standard for carbon dioxide 
(CO2) emissions from subsonic airplanes.
    The CO2 standard-setting process included input from 
governments, aircraft and engine manufacturers, non-governmental 
environmental organizations, research institutions, and academics 
worldwide. The standard-setting process occurred in two 3-year phases. 
The first phase focused on the development of the CO2 
certification requirement (a CO2 metric, test procedures, 
and measurement methodology). The second phase focused on the 
development of the CO2 standard itself (establishing 
regulatory limits, applicability, and assessments of cost 
effectiveness). The principles and key criteria that guided the process 
included the concepts that:

--No certification requirement compromise aircraft safety;
--Airplane CO2 emissions be reduced through the integration 
of fuel

[[Page 36077]]

efficient technologies in airplane type designs;
--Airplanes that incorporate differing generations of CO2 
reduction technologies be treated fairly and equitably;
--Any standard be independent of airplane size, purpose or utilization;
--The metric be robust and minimize unintended airplane and system 
design consequences;
--Any standard should use industry standard practices of measurement 
and correction; and
--The implementation of any standard reflects a manageable and 
appropriate level of resources to be expended by national airworthiness 
authorities and manufacturers.

    In February 2016, CAEP agreed on a new CO2 emission 
standard for certain airplanes. It was adopted by ICAO in March 2017 as 
Annex 16, Volume III.\1\
---------------------------------------------------------------------------

    \1\ Annex 16 to the Convention on International Civil Aviation, 
Environmental Protection, Volume III, Aeroplane CO2 Emissions, First 
Edition, July 2017. https://store.icao.int/collections/annex-16-environmental-protection/products/annex-16-environmental-protection-volume-iii-aeroplane-co2-emissions.
---------------------------------------------------------------------------

    In the United States, the CAA directs the U.S. EPA to adopt 
standards applicable to the emission of any air pollutant from any 
class of aircraft engines. The CAA also directs the Secretary of 
Transportation (and by delegation, the Administrator of the FAA) to 
implement the standards adopted by the EPA, which takes place by the 
adoption of regulations in title 14 of the Code of Federal Regulations 
(CFR) that allow the certification of aircraft and aircraft engines to 
the EPA standard.
    On January 11, 2021, the EPA published a final rule \2\ adopting 
new domestic airplane greenhouse gas (GHG) emissions standards in new 
40 CFR part 1030. In accordance with the CAA, the FAA is proposing new 
certification regulations for certain airplanes to insure compliance 
with those standards. The applicability of these proposed regulations 
and the regulatory emissions limits in the United States are the same 
as those adopted by ICAO as its airplane CO2 emission 
standard.
---------------------------------------------------------------------------

    \2\ 86 FR 2136-2174, Final Rule, 40 CFR parts 87 and 1030, 
Control of Air Pollution from Airplanes and Airplane Engines: GHG 
Emission Standards and Test Procedures, Environmental Protection 
Agency.
---------------------------------------------------------------------------

    The FAA, EPA and ICAO each use different terminology to reference 
the same standards. In Annex 16 volume III, ICAO references its 
standard as CO2 emissions because the amount of 
CO2 emitted is directly proportional to the amount of fuel 
burned by an airplane at cruise speed and altitude. It is a commonly 
used term that fits well within ICAO's international goals to reduce 
the carbon footprint of aviation. The EPA rule references GHGs in 
recognition of airplane emissions of CO2 and another GHG, 
nitrous oxide (N2O). The EPA did not set limits on 
N2O emissions, noting that they are small and are 
proportionally reduced as CO2 is reduced. The FAA describes 
these same limits and procedures as measures of fuel efficiency since 
this proposed rule prescribes a measurement of aircraft performance 
determined by the specific air range (SAR) parameter to determine fuel 
efficiency. The three concepts--FAA's proposed fuel efficiency, the 
EPA's GHG emissions, and ICAO's CO2 emissions--are to be 
considered equivalent for purposes of implementation. The FAA is also 
making draft guidance material for part 38 available at the same time 
as this proposed rule, and has placed that draft Advisory Circular in 
the docket for comment.

II. Discussion of the Proposal

    Since this document proposes an entire new part in 14 CFR, the word 
``proposed'' has been eliminated throughout this preamble when 
referencing material for part 38 or its appendix. The term remains when 
discussing material that proposes to amend other parts of 14 CFR.

A. General

    Since the CAA vests authority to regulate airplane emissions with 
both the EPA and the FAA, the regulations adopted by each agency bear a 
particular relationship to each other. In January 2021, the EPA adopted 
regulations limiting the GHG emissions from certain airplanes in 40 CFR 
part 1030. The emission standard described by the FAA here as new 14 
CFR part 38 is intended to be the same as that adopted by the EPA. In 
the event that the EPA changes the standard in 40 CFR part 1030, and 
until part 38 is amended with the same change, a certification 
applicant may request a waiver of those provisions as they appear in 
part 38 and instead comply with 40 CFR part 1030 (see Sec.  38.9 
(Relationship to other regulations)).
    The FAA is including a definitions section as Sec.  38.3 that 
includes terms specific to fuel efficiency certification. The term that 
may be less familiar is Maximum Take Off Mass (MTOM), which is the 
international standard term for aircraft weight expressed in kilograms. 
Terms that are used in 40 CFR part 1030 will carry the same meaning 
when used in part 38, unless otherwise defined in part 38 (see Sec.  
38.3 (Definitions)). The FAA has followed this process for changes to 
the aircraft engine emissions standards adopted in 14 CFR part 34, 
which were also promulgated under the CAA paradigm. Finally, Sec.  38.7 
(Reserved) will list the materials to be incorporated by reference into 
part 38 when those materials are determined.
    As developed by ICAO, the standard adopted by the EPA includes 
three occasions at which an airplane becomes subject to the GHG 
standards. These same applicability points are proposed here: at new 
type certification, the manufacture of any covered airplane after 
January 1, 2028, and when an airplane modification that triggers the 
criteria is made. While all three are contained in the applicability 
criteria of Sec.  38.1, the change criteria are also described in 
further detail in Sec.  38.19.

B. Applicability (Sec.  38.1)

    Section 38.1 describes the airplanes subject to the rule. Although 
the ICAO standard on which these regulations are based was effective 
January 1, 2020, the effective date of the EPA regulation implementing 
the standard is January 11, 2021. Except for the effective date, the 
EPA and FAA regulations are intended to have the same applicability as 
ICAO's standard. The difference in effective dates between the ICAO and 
EPA standards had no practical effect in the United States. In the 
twelve months between the effective date of the ICAO standard and the 
effective date of the EPA standards, the FAA received no applications 
for type certification for any applicable airplane type. While the 
emission standard is now applicable in the United States through 40 CFR 
part 1030, the FAA is not aware of any new airplane model for which a 
type certification application would be submitted before the 
certification regulations here are expected to be adopted. Once an 
airplane is type-certificated for fuel efficiency in accordance with 
this rule, all airplanes produced under that type certificate must 
comply with the fuel efficiency requirements.
    In reviewing the EPA standard as part of the development of this 
rule, the FAA determined that the difference between applicability 
statements in ICAO's Standards and Recommended Practices and those in 
the EPA and FAA regulations resulted in certain airplanes being omitted 
from the EPA applicability section. Those airplanes are described in 
Sec.  38.1(a)(1)(iv)-(vi). The airplanes would have a maximum takeoff 
mass (MTOM) of more than 60,000 kg and be type-certificated for a 
maximum passenger seating capacity of

[[Page 36078]]

19 seats or fewer. The FAA has advised the EPA of this finding and of 
the inclusion of the airplanes in part 38 applicability.
    An airplane that was type-certificated before the applicable 
compliance date listed in Sec.  38.1 may be required to demonstrate 
compliance with the fuel efficiency standard if certain modifications 
to the airplane that, in general, would affect the fuel efficiency of 
the airplane, are incorporated after January 1, 2023 (Sec.  38.1(a)(4) 
and (5)). Changes to airplanes and the effect of those changes on 
compliance with the fuel efficiency regulations are discussed more 
fully in the section on change criteria (section G.) below.
    Included in the applicability section is the requirement that all 
covered airplanes manufactured after January 1, 2028, regardless of the 
date of type certification, would have to meet the fuel efficiency 
requirements of part 38. Airplanes manufactured after that date would 
not be eligible for an original certificate of airworthiness unless 
compliance with part 38 has been shown. This manufacturing cutoff date 
effectively places a cutoff on the period during which an airplane not 
previously certificated for fuel efficiency might become subject to the 
requirement by introducing a modification, as described in the section 
below on change criteria.
    The applicability section of part 38 is particularly complex and 
examples of the effect of this part on selected popular operational 
categories of airplanes is summarized in table 1 below.

                                                       Table 1--Quick Reference for Applicability
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                      Effective dates for
     Individual airplane status        Applicability today     Applicability when    applicability of part     Fuel efficiency              Note
                                                                    modified                   38            metric (FEM)  limit
--------------------------------------------------------------------------------------------------------------------------------------------------------
In service, and type is no longer    None..................  none..................  none.................  none.................  May voluntarily apply
 being produced EX: 757.                                                                                                            to establish an FEM
                                                                                                                                    value.
                                                                                                                                   Status would only
                                                                                                                                    change if a new
                                                                                                                                    airplane is
                                                                                                                                    produced.
In service, and new airplanes still  None..................  Must comply with the    1/1/2023 for modified  In-production limit    [intentionally left
 being produced EX: 737 MAX 8.                                in-production limit     airplanes Sec.         Sec.   38.17(a)(5)-    blank]
                                                              if: (1) produced        38.1(a)(4)-(5).        (8).
                                                              after 1/1/2023 and     1/1/2028 for all new
                                                              (2) includes a          production Sec.
                                                              modification that       38.1(a)(6)-(7).
                                                              changes the FEM value
                                                              (Sec.   38.19(c)).
New Type: large jet airplanes and    Sec.   38.1(a)(1) and   All airplanes; New      1/11/2021............  New type limit Sec.    [intentionally left
 propeller-driven airplanes           (3).                    certification                                  38.17(a)(1)-(4).       blank]
 produced under new type                                      required if triggered
 certificates applied for after 1/                            by change criteria
 11/2021.                                                     (Sec.   38.19(a)).
New Type: small airplanes produced   Sec.   38.1(a)(2).....  All airplanes; New      1/1/2023.............  New type limit Sec.    [intentionally left
 under new type certificates                                  certification                                  38.17(a)(1).           blank]
 applied for after 1/1/2023.                                  required if triggered
                                                              by change criteria
                                                              (Sec.   38.19(a)).
--------------------------------------------------------------------------------------------------------------------------------------------------------

    The FAA is proposing the same exclusions to part 38 that were 
adopted by the EPA and ICAO. Part 38 would not apply to airplanes with 
lesser MTOMs (jets or propeller-driven airplanes) as indicated in Sec.  
38.1(c). Airplanes that are designed for specialized operations 
(including the presence of unique design features to carry out those 
operations) also would be excluded from part 38, subject to a 
determination that a design for specialized operation is detrimental to 
fuel efficiency. This determination would be made by the FAA when an 
airplane is presented for certification. Examples of such airplanes 
could include specialized cargo features, specialized missions, or crop 
dusting. Amphibious airplanes (as defined in Sec.  38.3), airplanes 
that have no pressurized areas (described as having zero reference 
geometric factor (RGF)), airplanes designed for firefighting, and 
airplanes powered by reciprocating aircraft engines also would be 
excluded.

C. Compatibility With Airworthiness Requirements (Sec.  38.4)

    Section 38.4 addresses historical issues of compatibility between 
environmental and airworthiness standards. This section is intended to 
prohibit the sequencing of certification tests for an airplane that has 
not met the applicable airworthiness requirements. This requirement 
would ensure that critical airplane configuration is established before 
fuel efficiency certification tests are conducted, and that no 
airworthiness standards are compromised during the fuel efficiency 
certification. In addition, the FAA proposes to require that all of the 
procedures used to conduct the flights that demonstrate fuel efficiency 
compliance be conducted in compliance with all airworthiness 
regulations that apply to the airplane.

D. Exemptions (Sec.  38.5)

    In accordance with 42 U.S.C. 7572, 49 CFR 1.83(a)(6) and (c), and 
49 U.S.C. 44701(f), the FAA may issue exemptions from its regulations 
when such exemption would be in the public interest. Section 38.5 
states that petitions for exemption from any requirement in part 38 be 
submitted in accordance with 14 CFR part 11. In addition, this section 
notes that the FAA would consult with the EPA on any request for 
exemption from the regulations of part 38. This process is the same as 
that followed when the FAA considers petitions for exemption from the 
engine emissions standards promulgated by the EPA under 40 CFR part 87, 
and by the FAA in 14 CFR part 34.

E. Fuel Efficiency Metric (Sec.  38.11)

    The fuel efficiency of an airplane is determined by the amount of 
fuel it uses to travel a certain distance under prescribed conditions. 
This measure is the fuel efficiency metric (FEM). For each airplane 
subject to part 38 (including an airplane subject to the change 
criteria of Sec.  38.19), Sec.  38.11 would require an FEM value to be 
calculated using an equation identical to the one adopted by the EPA in 
40 CFR 1030.20. As described in Sec.  38.11, the two primary components 
of the FEM to be certificated are the specific air range

[[Page 36079]]

(SAR) (described in Sec.  38.13) and the reference geometric factor 
(RGF) (described in Sec.  38.15). SAR is a familiar aeronautical 
parameter used in the aviation industry to represent the distance an 
airplane can travel per unit of fuel consumed. It measures the 
instantaneous fuel efficiency of an airplane at any point during stable 
cruise flight. The RGF is a representation of airplane fuselage size 
based on productivity or load carrying capability. The RGF parameter is 
based on the floor area of pressurized space in an airplane, and is 
flexible enough to account for single or multi-deck airplanes. Dividing 
SAR by RGF results in a universal equation to denote the fuel 
efficiency of any airplane regardless of size. This is the FEM.

F. Fuel Efficiency Regulatory Limits (Sec.  38.17)

    Section 38.17 incorporates as fuel efficiency limits the emission 
standards adopted by the EPA in 40 CFR 1030.30. Airplanes subject to 
part 38 would be required to demonstrate that the FEM value does not 
exceed the fuel efficiency limits in Sec.  38.17. Using the applicable 
provision in Sec.  38.1, the fuel efficiency limit is calculated using 
the airplane's MTOM and the equations listed in the last column of the 
table in Sec.  38.17(b). An airplane's FEM value may not exceed the 
maximum FEM value calculated using the fuel efficiency limits in this 
rule.
    For the airplanes omitted from the applicability section in the EPA 
regulations (jet airplanes with a maximum passenger seating capacity of 
19 or fewer seats and a MTOM greater than 60,000kg, and for which 
application for original type certification is submitted on or after 
January 11, 2021), the standard associated with the airplane's MTOM is 
applied rather than its seating capacity, which is consistent with the 
ICAO standard. These airplanes would carry the applicability in Sec.  
38.1(a)(1) and would be required to meet the fuel efficiency limits in 
Sec.  38.17(b)(3) and (4).

G. Change Criteria (Sec.  38.19)

    The third occasion at which the fuel efficiency requirement would 
apply is at the time certain modifications are made. Section 38.19 
would adopt the EPA airplane change criteria of 40 CFR 1030.35. 
Airplanes routinely have modifications incorporated into their designs. 
A modification may change the compliance status of an airplane under 
part 38, regardless of whether it was required to demonstrate 
compliance with part 38 at the time of certification. The modifications 
affecting compliance are described by the change criteria in Sec.  
38.19. The requirements differ depending on whether an airplane has 
demonstrated compliance (at certification) before a modification is 
made, or for an airplane that was type certificated before January 11, 
2021, and was not required to demonstrate compliance.
    First, if an airplane that was previously certificated for fuel 
efficiency under part 38 undergoes a modification that increases its 
MTOM, the applicant must demonstrate compliance with the applicable 
fuel efficiency limit of Sec.  38.17, regardless of whether there is a 
change in the airplane's FEM value.
    If the MTOM of a modified airplane is not increased, the applicant 
must show compliance with part 38 if the FEM value of the airplane 
increases by more than the criteria specified in Sec.  38.19(a)(2). For 
example, the addition of a satellite antenna on top of the fuselage of 
an airplane with a MTOM of 60,000 kg may not affect the airplane's 
MTOM, but may adversely affect the airplane's FEM value by increasing 
drag. If this 60,000kg MTOM modified airplane shows an increase of FEM 
value of more than 0.75% (as calculated under Sec.  38.19(a)(2)), the 
applicant would need to demonstrate compliance with the fuel efficiency 
limit that was established for the prior version of the airplane.
    If the FEM value of the modified airplane increases by less than 
0.75%, no new demonstration of compliance would be required. When no 
demonstration of compliance is required, the applicant may choose to 
use the FEM value of the unmodified version of the airplane under Sec.  
38.19(b), or it may choose to establish a new FEM value.
    Second, as provided in Sec.  38.1(a)(4) or (5), if a modification 
is made to an airplane not previously certificated for fuel efficiency, 
it may be subject to the requirements of part 38 depending upon the 
effect of the modification on the FEM value. Section 38.19(c) requires 
that if a modified airplane has an increase in FEM value of more than 
1.5% over the unmodified version, the applicant must demonstrate 
compliance with the fuel efficiency limit of Sec.  38.17. The fuel 
efficiency limits for these airplanes are shown in Sec.  38.17(b)(5) 
through (8). These change criteria apply to airplanes for which an 
application for the modification in type design is submitted on or 
after January 1, 2023.
    Finally, Sec.  38.1(a)(6) and (7), which require that all covered 
airplanes produced after January 1, 2028, demonstrate compliance with 
the fuel efficiency standard (regardless of when the airplane model was 
originally type certificated), effectively limit to five years the 
applicability of the 2023 provisions established in Sec.  38.1(a)(4) 
and (5). For aircraft that were not required to demonstrate compliance 
with the standard at certification, the effective period of the change 
criteria trigger for compliance is January 1, 2023, to December 31, 
2027. For aircraft that have been previously required to demonstrate 
compliance with the standard at type certification or production, the 
change criteria of Sec.  38.19 would continue to apply.
    Examples of the limits on allowable changes after modification are 
illustrated in Figure 1, Changes to FEM following modification.
    The example on the left of the chart is for an airplane that was 
type certificated before January 11, 2021 (In-production limit/hashed 
line with applicable regulations noted), that was not required to 
demonstrate compliance with part 38. The dot on the chart represents 
the airplane before the modification in question. An airplane that is 
modified complies with part 38 if it stays below the hashed line (the 
triangle), even if the FEM is higher than the unmodified airplane. If 
the modification results in an FEM above the hashed line (the square), 
the modified airplane would not be compliant with part 38 and would not 
be issued an airworthiness certificate. The example illustrates a 
concurrent increase in MTOM, which may not occur.
    The example on the right is for an airplane type certificated after 
January 11, 2021, that has demonstrated compliance with part 38 at type 
certification (solid line, with applicable regulations noted). The 
result is the same, with a modified airplane being required to stay 
below the limit line for new airplane types (denoted by the triangle 
relative to the solid regulatory line). The illustration emphasizes the 
fact that airplanes produced under a new type certificate (subject to 
the solid line) do not become ``in-production'' airplanes that may use 
the higher FEM limit (the square) when produced after initial part 38 
certification. The designation of ``in-production'' versus ``new 
airplane type'' under the change criteria is established as of January 
11, 2021, not the date of individual airplane production, and the FEM 
limit (line) for modified airplanes does not change afterwards.

[[Page 36080]]

[GRAPHIC] [TIFF OMITTED] TP15JN22.000

H. Approval Before Compliance Testing (Sec.  38.21)

    Section 38.21 would require FAA approval of all procedures, 
weights, configurations, and other information that are necessary to 
calculate the fuel efficiency metric value of an airplane. Such 
approvals are necessary to ensure the airplane configuration and fuel 
efficiency certification procedures are established and remain 
unchanged before fuel efficiency compliance tests are actually 
conducted. This section would not be applied to data submitted for 
validation following fuel efficiency certification by another 
authority.

I. Manual Information and Limitations (Sec.  38.23)

    The final section of part 38 would require that the fuel efficiency 
metric value of the airplane, along with other part 38 compliance 
information, must be placed in an FAA-approved section of the flight 
manual of the airplane. Inclusion of this information in the approved 
airplane flight manual would provide owners, operators, and flight crew 
with information regarding the airplane's compliance with part 38. The 
FAA also proposes to require that if a weight less than the MTOM is 
used for fuel efficiency certification, then that lower weight becomes 
an operating limitation for that airplane and must be included in the 
operating limitations section of the flight manual. Operators may not 
exceed the weight at which compliance with part 38 was demonstrated, 
even if that weight is lower than the MTOM for the airplane under other 
airworthiness requirements.

J. Appendix A to Part 38

    Appendix A to part 38 provides the technical detail needed to 
determine the fuel efficiency metric value of an airplane required to 
demonstrate compliance with part 38. The primary sources of the 
information contained in the appendix are Sections 2.5 and 2.6 of ICAO 
Annex 16, Volume III, including appendices 1 and 2 to that volume. The 
FAA is not proposing the incorporation by reference of Volume III. 
Instead, part 38 was drafted to include the material from Volume III 
using current U.S. certification terminology, format, and references.
    Appendix A details the processes and procedures to be used when 
measuring an airplane for fuel efficiency. To comply with part 38, a 
certification applicant would need to determine the core elements of 
the fuel efficiency metric, specifically the specific air range and 
reference geometric factor. The specifications for the flight tests to 
gather airplane performance data are provided in this appendix, as well 
as the formulas to be used to determine specific air range and the 
reference geometric factor from the data gathered during testing. The 
appendix also describes the certification data that would be submitted 
to the FAA in the certification test report that is a part of fuel 
efficiency certification.

K. Other Revisions to 14 CFR

    This proposal sets forth several amendments to part 21 to include 
compliance with part 38 as a requirement for type, supplemental type, 
or airworthiness certification using the applicability described in 
Sec.  38.1. The proposed amendments to part 21 include references to 
proposed part 38 in Sec. Sec.  21.5, 21.17, 21.29, 21.31, 21.93, 
21.115, 21.183, and 21.187.
    While revising the text for part 21 to include references to 
proposed part 38, an error was discovered in Sec.  21.187. The text of 
Sec.  21.187(c) should have been designated as paragraph (a)(3) because 
the applicability of part 34 needs the introductory text of paragraph 
(a) to be read correctly. This rule proposes to move and redesignate 
Sec.  21.187(c) as Sec.  21.187(a)(3), with the requirement to comply 
with part 38 added as Sec.  21.187(a)(4).
    This proposed rule includes amendments to the operating regulations 
for airplanes subject to part 38. Revisions to Sec. Sec.  121.141 and 
125.75 are included to add the certification information for fuel 
efficiency to the airplane flight manuals for airplanes subject to part 
38.

III. Regulatory Notices and Analyses

    Federal agencies consider impacts of regulatory actions under a 
variety of executive orders and other requirements. First, Executive 
Order 12866 and Executive Order 13563 direct that each Federal agency 
shall propose or adopt a regulation only upon a

[[Page 36081]]

reasoned determination that the benefits of the intended regulation 
justify the 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. 
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 that may result in the expenditure by State, local, and 
tribal governments, in the aggregate, or by the private sector, of 
$100,000,000 or more (adjusted annually for inflation) in any one year. 
The current threshold after adjustment for inflation is $158,000,000, 
using the most current (2020) Implicit Price Deflator for the Gross 
Domestic Product. The FAA has provided a detailed Regulatory Impact 
Analysis (RIA) in the docket for this rulemaking. This portion of the 
preamble summarizes the FAA's analysis of the economic impacts of this 
rule.
    In conducting these analyses, the FAA has determined that this 
rule: will result in benefits that justify costs; is not a 
``significant regulatory action'' as defined in section 3(f) of 
Executive Order 12866; will not have a significant economic impact on a 
substantial number of small entities; will not create unnecessary 
obstacles to the foreign commerce of the United States; and will not 
impose an unfunded mandate on State, local, or tribal governments, or 
on the private sector.

A. Regulatory Impact Analysis

    The FAA identified three U.S. manufacturers that would be affected 
by the proposed rule. Manufacturers will incur certification costs even 
in the absence of the proposed rule since they would pursue 
certification with foreign authorities.\3\ Certification tasks will 
vary greatly depending on the stage of the airplane development process 
(e.g., new type certificate, supplemental type certificate). 
Additionally, the first fuel efficiency certification project 
undertaken by any one manufacturer may require more resources because 
of the new processes and the need for new data generation. The FAA used 
information provided by the affected airplane manufacturers to 
construct a timeline of when these costs would be incurred over the 
next 10 years (starting in 2022), and the cost savings from domestic 
certification enabled by the proposed rule.
---------------------------------------------------------------------------

    \3\ The EPA also conducted its own analysis and found that 
manufacturers will comply with the ICAO standards in the absence of 
U.S. regulations.
---------------------------------------------------------------------------

    Because the EPA standard applies to airplanes certificated in the 
United States even in the absence of the proposed rule, there are no 
incremental benefits associated with the FAA's action; however, the 
proposed rule will result in cost savings by enabling U.S. 
manufacturers to certificate to the EPA standard \4\ rather than the 
requirements of a foreign authority. Annualized costs savings may be 
approximately $0.4 million using discount rates of 3 percent and 7 
percent (a present value over 10 years of $3.12 million to $2.6 
million, using discount rates of 3 percent and 7 percent, 
respectively). For more details, see the Regulatory Impact Analysis 
(RIA) for this proposed rule, which has been placed in the rule docket.
---------------------------------------------------------------------------

    \4\ The EPA adopted the same emission standard as ICAO; 
manufacturers would have to comply with the national emission 
standard of another country, usually based on the ICAO standard, in 
order to sell its airplanes there.
---------------------------------------------------------------------------

B. Regulatory Flexibility Act

    The Regulatory Flexibility Act (RFA) of 1980, Public Law 96-354, 94 
Stat. 1164 (5 U.S.C. 601-612), as amended by the Small Business 
Regulatory Enforcement Fairness Act of 1996 (Pub. L. 104-121, 110 Stat. 
857, Mar. 29, 1996) and the Small Business Jobs Act of 2010 (Pub. L. 
111-240, 124 Stat. 2504 Sept. 27, 2010), requires Federal agencies to 
consider the effects of the regulatory action on small business and 
other small entities and to minimize any significant economic impact. 
The term ``small entities'' comprises small businesses and not-for-
profit organizations that are independently owned and operated and are 
not dominant in their fields, and governmental jurisdictions with 
populations of less than 50,000.
    As described in the RIA, the FAA identified three U.S. 
manufacturers that would be affected by the proposed rule. Based on the 
Small Business Administration (SBA) size standard for aircraft 
manufacturing (Table 1), all three manufacturers are large businesses. 
If an agency determines that a rulemaking will not result in a 
significant economic impact on a substantial number of small entities, 
the head of the agency may so certify under section 605(b) of the RFA. 
Therefore, as provided in section 605(b) and based on the foregoing, 
the head of FAA certifies that this rulemaking will not result in a 
significant economic impact on a substantial number of small entities. 
The FAA welcomes comments on the basis for this certification.

       Table 2--Small Business Size Standards: Air Transportation
------------------------------------------------------------------------
           NAICS code                 Description       Size  standard
------------------------------------------------------------------------
336411..........................  Aircraft            1,500 employees.
                                   manufacturing.
------------------------------------------------------------------------
Source: SBA (2019).\5\
NAICS = North American Industrial Classification System.

C. International Trade Impact Assessment
---------------------------------------------------------------------------

    \5\ Small Business Administration (SBA). 2019. Table of Size 
Standards. Effective August 12, 2019. https://www.sba.gov/document/support--table-size-standards.
---------------------------------------------------------------------------

    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.
    The FAA has assessed the potential effects of this rule and finds 
that it does not create an unnecessary obstacle to foreign commerce. 
The United States has adopted the same airplane emission standard as 
ICAO and many of its member States. This proposed rule is the next step 
in insuring compliance with the internationally recognized standard.

D. Unfunded Mandates Assessment

    The Unfunded Mandates Reform Act of 1995 (2 U.S.C. 1531-1538) 
governs the issuance of Federal regulations that require unfunded 
mandates. An unfunded mandate is a regulation that requires a State, 
local, or tribal government or the private sector to incur direct costs 
without the Federal Government having first provided the funds to pay 
those costs. The FAA determined that the proposed rule will not result 
in the expenditure of $158,000,000 or more by State, local, or tribal 
governments, in the aggregate, or the private sector, in any one year.

[[Page 36082]]

E. Paperwork Reduction Act

    The Paperwork Reduction Act of 1995 (44 U.S.C. 3507(d)) requires 
that the 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 action contains the following proposed new information 
collection requirement. As required by the Paperwork Reduction Act of 
1995 (44 U.S.C. 3507(d)), the FAA has submitted these proposed 
information collection amendments to OMB for its review.
    Summary: The proposed regulations, adding a new part 38 to 14 CFR 
that requires certification for fuel efficiency, includes a collection 
of data from certification applicants. Certain data collected by the 
respondent during its certification flight tests are to be included in 
a certification test report that is submitted to the FAA. Those data 
are described in appendix A to part 38. The information in the test 
report is used by the agency to determine whether the subject airplane 
complies with the fuel efficiency requirements promulgated by the EPA 
and the FAA. Without such information, the FAA would not have the 
complete record of an airplane's fuel efficiency performance and would 
be unable to issue a type or airworthiness certificate.
    Use: Respondent's data will be used to determine compliance with 
the fuel efficiency standards established by the EPA under the 
requirements of the Clean Air Act. The FAA is required by the CAA to 
implement those standards, which is done at the time of aircraft 
certification.
    Respondent's test data will not be maintained by the FAA following 
a certification determination. The certification test report is not 
available to the public. The regulation also requires that certain 
values be listed in the flight manual of the airplane, which is given 
to the purchaser of an airplane.
    Respondents (including number of): The FAA anticipates three 
respondents to the collection of information.
    Frequency: The FAA anticipates that respondents will provide 
responses annually (averaged).
    Annual Burden Estimate: Table 1 provides the FAA's estimates of 
annual reporting (submittal of certification data) and recordkeeping 
(manual information) burden.

                    Table 1--Summary of Annual Burden
------------------------------------------------------------------------
                   Category                     Reporting  Recordkeeping
------------------------------------------------------------------------
# of respondents..............................          3             3
# of responses per respondent.................          2             2
Time per response (hours).....................          2             8
Total # of responses..........................          5             5
Total burden (hours)..........................          9            36
------------------------------------------------------------------------

    The agency is soliciting comments to--
    (1) Evaluate whether the proposed information requirement is 
necessary for the proper performance of the functions of the agency, 
including whether the information will have practical utility;
    (2) Evaluate the accuracy of the agency's estimate of the burden;
    (3) Enhance the quality, utility, and clarity of the information to 
be collected; and
    (4) Minimize the burden of collecting information on those who are 
to respond, including by using appropriate automated, electronic, 
mechanical, or other technological collection techniques or other forms 
of information technology.
    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 August 15, 2022. Comments also 
should be submitted to the Office of Management and Budget, Office of 
Information and Regulatory Affairs, Attention: Desk Officer for FAA, 
New Executive Building, Room 10202, 725 17th Street NW, Washington, DC 
20053.

F. International Compatibility and Cooperation Act

    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. The FAA has 
reviewed the corresponding ICAO Standards and Recommended Practices and 
has identified no substantive differences with these proposed 
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. The FAA has 
determined this rulemaking action qualifies for the categorical 
exclusion identified in paragraph 5-6.6f for regulations and involves 
no extraordinary circumstances.

H. DOT Order 2100.6A--Rulemaking and Guidance Procedures

    On June 7, 2021, the Department of Transportation issued Order 
2100.6A, Rulemaking & Guidance Procedures, calling for identification 
of topics that are ``reasonably anticipated to be related to a major 
program, policy, or activity of the Department or a high-profile issue 
pending for decision before the Department; involve one of the 
Secretary's top policy priorities; or to garner significant press or 
congressional attention.'' Reducing the impacts of climate change is 
considered a major policy goal of the current administration. This 
proposed rule addresses the certification of fuel efficiency for 
subsonic, civil airplanes and addresses a portion of the role that 
civil aviation plays in climate change. Airplanes emit CO2, 
a greenhouse gas, as they burn fuel. This proposed rule would require 
the measurement of the fuel efficiency of an airplane as a tool for 
assessing the continued output of CO2 from airplanes and 
informing future standards limiting CO2 emissions.

IV. Executive Order Determinations

A. Executive Order 13132, Federalism

    The FAA has analyzed this proposed rule under the principles and 
criteria of Executive Order (E.O.) 13132, Federalism. The agency has 
determined that this action would 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, would not have 
federalism implications.

B. Executive Order 13211, Regulations That Significantly Affect Energy 
Supply, Distribution, or Use

    The FAA analyzed this proposed rule under E.O. 13211, Actions 
Concerning Regulations that Significantly Affect Energy Supply, 
Distribution, or Use (May 18, 2001). The agency has determined that it 
would not be a ``significant energy action'' under the executive order 
and would not be 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

[[Page 36083]]

(77 FR 26413, May 4, 2012), promotes international regulatory 
cooperation to meet shared challenges involving health, safety, labor, 
security, environmental, and other issues and reduce, eliminate, or 
prevent unnecessary differences in regulatory requirements. The FAA has 
analyzed this action under the policy and agency responsibilities of 
E.O. 13609. The agency has determined that this action would eliminate 
differences between U.S. aviation standards and those of other civil 
aviation authorities by adopting the airplane certification regulations 
needed to comply with the standards adopted by ICAO and the U.S. EPA.

V. Additional Information

A. Comments Invited

    The FAA invites interested persons to participate in this 
rulemaking by submitting written comments, data, or views. The agency 
also invites 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, commenters should send only one copy of written 
comments, or if comments are filed electronically, commenters should 
submit only one time.
    The FAA will file in the docket all comments it receives, as well 
as a report summarizing each substantive public contact with FAA 
personnel concerning this proposed rulemaking. Before acting on this 
proposal, the FAA will consider all comments it receives on or before 
the closing date for comments. The FAA will consider comments filed 
after the comment period has closed if it is possible to do so without 
incurring expense or delay. The agency may change this proposal in 
light of the comments it receives.
    Confidential Business Information: Confidential Business 
Information (CBI) is commercial or financial information that is both 
customarily and actually treated as private by its owner. Under the 
Freedom of Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from 
public disclosure. If your comments responsive to this NPRM contain 
commercial or financial information that is customarily treated as 
private, that you actually treat as private, and that is relevant or 
responsive to this NPRM, it is important that you clearly designate the 
submitted comments as CBI. Please mark each page of your submission 
containing CBI as ``PROPIN.'' The FAA will treat such marked 
submissions as confidential under the FOIA, and they will not be placed 
in the public docket of this NPRM. Submissions containing CBI should be 
sent to the person listed in FOR FURTHER INFORMATION CONTACT above. Any 
commentary that the FAA receives which is not specifically designated 
as CBI will be placed in the public docket for this rulemaking.

B. Availability of Rulemaking Documents

    An electronic copy of rulemaking documents may be obtained from the 
internet by--
    1. Searching the Federal eRulemaking Portal at www.regulations.gov;
    2. Visiting the FAA's Regulations and Policies web page at 
www.faa.gov/regulations_policies; or
    3. Accessing the Government Printing Office's web page at 
www.govinfo.gov.
    Copies may also be obtained 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) 267-9677. 
Commenters must identify the docket or notice number of this 
rulemaking.
    All documents the FAA considered in developing this proposed rule, 
including economic analyses and technical reports, may be accessed from 
the internet through the Federal eRulemaking Portal referenced in item 
(1) above.

List of Subjects

14 CFR Part 21

    Aircraft, Aviation safety, Exports, Imports, Reporting and 
recordkeeping requirements.

14 CFR Part 38

    Air pollution control, Aircraft.

14 CFR Part 121

    Air carriers, Aircraft, Airmen, Aviation safety, Charter flights, 
Reporting and recordkeeping requirements, Safety, Transportation.

14 CFR Part 125

    Aircraft, Airmen, Aviation safety, Reporting and recordkeeping 
requirements.

    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 ARTICLES

0
1. The authority citation for part 21 continues to read as follows:

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

0
2. Amend Sec.  21.5 by adding paragraph (b)(3) to read as follows:

Sec.  21.5   Airplane or Rotorcraft Flight Manual.

* * * * *
    (b) * * *
    (3) Documentation of compliance with part 38 of this chapter, in an 
FAA-approved section of any approved airplane flight manual. Such 
material must include the fuel efficiency metric value as calculated 
under Sec.  38.11 of this chapter, and the specific paragraph of Sec.  
38.17 of this chapter with which compliance has been shown for that 
airplane.
0
3. Amend Sec.  21.17 by revising the introductory text of paragraph (a) 
to read as follows:

Sec.  21.17   Designation of applicable regulations.

    (a) Except as provided in Sec. Sec.  25.2, 27.2, and 29.2 of this 
subchapter, and in parts 26, 34, 36, and 38 of this subchapter, an 
applicant for a type certificate must show that the aircraft, aircraft 
engine, or propeller concerned meets--
* * * * *
0
4. Amend Sec.  21.29 by revising paragraphs (a)(1)(i) and (b) to read 
as follows:

Sec.  21.29   Issue of type certificate: import products.

    (a) * * *
    (1) * * *
    (i) The applicable aircraft noise, fuel venting and exhaust 
emissions, and fuel efficiency requirements of this subchapter as 
designated in Sec.  21.17, or the applicable aircraft noise, fuel 
venting and exhaust emissions, and fuel efficiency requirements of the 
State of Design, and any other requirements the FAA may prescribe to 
provide noise, fuel venting and exhaust emission, and fuel efficiency 
levels no greater than those provided by the applicable aircraft noise, 
fuel venting and exhaust emissions, and fuel efficiency requirements of 
this subchapter as designated in Sec.  21.17; and
* * * * *
    (b) A product type certificated under this section is determined to 
be compliant with the fuel venting and

[[Page 36084]]

exhaust emission standards of part 34 of this subchapter, the noise 
standards of part 36 of this subchapter, and the fuel efficiency 
requirements of part 38 of this subchapter. Compliance with parts 34, 
36, and 38 of this subchapter is certified under paragraph (a)(1)(i) of 
this section, and the applicable airworthiness standards of this 
subchapter, or an equivalent level of safety, with which compliance is 
certified under paragraph (a)(1)(ii) of this section.
0
5. Amend Sec.  21.31 by revising paragraph (e) to read as follows:

Sec.  21.31   Type design.

* * * * *
    (e) Any other data necessary to allow, by comparison, the 
determination of the airworthiness, noise characteristics, fuel 
efficiency, fuel venting, and exhaust emissions (where applicable) of 
later products of the same type.
0
6. Amend Sec.  21.93 by adding paragraph (d) to read as follows:

Sec.  21.93   Classification of changes in type design.

* * * * *
    (d) For the purpose of maintaining compliance with part 38 of this 
chapter, any voluntary change in the type design of an airplane that 
may increase the fuel efficiency metric value of that airplane is a 
``fuel efficiency change'', in addition to being a minor or major 
change as classified in paragraph (a) of this section.
0
7. Amend Sec.  21.101 by revising paragraph (a) to read as follows:

Sec.  21.101   Designation of applicable regulations.

    (a) An applicant for a change to a type certificate must show that 
the change and areas affected by the change comply with the 
airworthiness requirements applicable to the category of the product in 
effect on the date of the application for the change and with parts 34, 
36, and 38 of this chapter. Exceptions are detailed in paragraphs (b) 
and (c) of this section.
* * * * *
0
8. Amend Sec.  21.115 by revising paragraph (a) to read as follows:

Sec.  21.115   Applicable requirements.

    (a) Each applicant for a supplemental type certificate must show 
that the altered product meets applicable requirements specified in 
Sec.  21.101 and--
    (1) In the case of an acoustical change described in Sec.  
21.93(b), show compliance with the applicable noise requirements of 
part 36 of this chapter;
    (2) In the case of an emissions change described in Sec.  21.93(c), 
show compliance with the applicable fuel venting and exhaust emissions 
requirements of part 34 of this chapter; and
    (3) In the case of a fuel efficiency change described in Sec.  
21.93(d), show compliance with the applicable fuel efficiency 
requirements of part 38 of this chapter.
* * * * *
0
9. Amend Sec.  21.183 by adding reserved paragraph (i) and paragraph 
(j) to read as follows:

Sec.  21.183   Issue of standard airworthiness certificates for normal, 
utility, acrobatic, commuter, and transport category aircraft; manned 
free balloons; and special classes of aircraft.

* * * * *
    (j) Fuel efficiency requirements. No original standard 
airworthiness certificate may be issued under this section unless the 
applicant has demonstrated that the type design complies with the 
applicable fuel efficiency requirements of part 38 of this chapter.
0
10. Amend Sec.  21.187 by revising paragraph (a) to read as follows:

Sec.  21.187   Issue of multiple airworthiness certification.

    (a) An applicant for an airworthiness certificate in the restricted 
category, and in one or more other categories except primary category, 
is entitled to the certificate, if--
    (1) He shows compliance with the requirements for each category, 
when the aircraft is in the configuration for that category;
    (2) He shows that the aircraft can be converted from one category 
to another by removing or adding equipment by simple mechanical means;
    (3) The aircraft complies with the applicable requirements of part 
34 of this subchapter; and
    (4) The airplane complies with the applicable requirements of part 
38 of this subchapter.
* * * * *
0
11. Add part 38 to read as follows:

PART 38--AIRPLANE FUEL EFFICIENCY CERTIFICATION

Subpart A--General
Sec.
38.1 Applicability.
38.3 Definitions.
38.4 Compatibility with airworthiness requirements.
38.5 Exemptions.
38.7 [Reserved]
38.9 Relationship to other regulations.
Subpart B--Determining Fuel Efficiency for Subsonic Airplanes
Sec.
38.11 Fuel efficiency metric.
38.13 Specific air range.
38.15 Reference geometric factor.
38.17 Fuel efficiency limits.
38.19 Change criteria.
38.21 Approval before compliance testing.
38.23 Manual information and limitations.
Appendix A to Part 38--Determination of Airplane Fuel Efficiency 
Metric Value

    Authority:  42 U.S.C. 4321 et seq., 7572; 49 U.S.C. 106(g), 
40113, 44701-44702, 44704; 49 CFR 1.83(c).

Subpart A--General

Sec.  38.1   Applicability.

    (a) Except as provided in paragraph (c) of this section, an 
airplane that is subject to the requirements of 40 CFR part 1030 may 
not exceed the fuel efficiency limits of this part when original type 
certification under this title is sought. This part applies to the 
following airplanes:
    (1) A subsonic jet airplane that has--
    (i) A type-certificated maximum passenger seating capacity of 20 
seats or more, and
    (ii) A maximum takeoff mass (MTOM) greater than 5,700 kg, and
    (iii) An application for original type certification that is 
submitted on or after January 11, 2021, or
    (iv) A type-certificated maximum passenger seating capacity of 19 
seats or fewer, and
    (v) A MTOM greater than 60,000 kg, and
    (vi) An application for original type certification that is 
submitted on or after January 11, 2021.
    (2) A subsonic jet airplane that has--
    (i) A type-certificated maximum passenger seating capacity of 19 
seats or fewer,
    (ii) A MTOM greater than 5,700 kg, but not greater than 60,000 kg, 
and
    (iii) An application for original type certification that is 
submitted on or after January 1, 2023.
    (3) A propeller-driven airplane that has--
    (i) A MTOM greater than 8,618 kg, and
    (ii) An application for original type certification that is 
submitted on or after January 11, 2021.
    (4) A subsonic jet airplane--
    (i) That is a modified version of an airplane whose type design was 
not certificated under this part,
    (ii) That has a MTOM greater than 5,700 kg,
    (iii) For which an application for the modification in type design 
is submitted on or after January 1, 2023, and
    (iv) For which the first certificate of airworthiness is issued for 
an airplane built with the modified type design.
    (5) A propeller-driven airplane--

[[Page 36085]]

    (i) That is a modified version of an airplane whose type design was 
not certificated under this part,
    (ii) That has a MTOM greater than 8,618 kg,
    (iii) For which an application for modification in type design is 
submitted on or after January 1, 2023, and
    (iv) For which the first certificate of airworthiness is issued for 
an airplane built with the modified type design.
    (6) A subsonic jet airplane that has--
    (i) A MTOM greater than 5,700 kg, and
    (ii) Its first certificate of airworthiness issued on or after 
January 1, 2028.
    (7) A propeller-driven airplane that has--
    (i) A MTOM greater than 8,618 kg, and
    (ii) Its first certificate of airworthiness issued on or after 
January 1, 2028.
    (b) The requirements of this part apply to an airplane that 
incorporates a modification that changes the fuel efficiency metric 
value of a prior version of that airplane. A modified airplane may not 
exceed the applicable fuel efficiency limit of this part when 
certification under this chapter is sought. The criteria for modified 
airplanes are described in Sec.  38.19. A modified airplane is subject 
to the same fuel efficiency limit of Sec.  38.17 as the prior version 
of the airplane.
    (c) The requirements of this part do not apply to:
    (1) Subsonic jet airplanes having a MTOM at or below 5,700 kg.
    (2) Propeller-driven airplanes having a MTOM at or below 8,618 kg.
    (3) Amphibious airplanes.
    (4) Airplanes initially designed, or modified and used, for 
specialized operations. These airplane designs may include 
characteristics or configurations necessary to conduct specialized 
operations that the United States Environmental Protection Agency (EPA) 
and the FAA have determined may cause a significant increase in the 
fuel efficiency metric value.
    (5) Airplanes designed with a reference geometric factor of zero.
    (6) Airplanes designed for, or modified and used for, firefighting.
    (7) Airplanes powered by reciprocating engines.

Sec.  38.3   Definitions.

    For the purpose of showing compliance with this part, the following 
terms have the specified meanings:
    Amphibious airplane means an airplane that is capable of takeoff 
and landing on both land and water. Such an airplane uses its hull or 
floats attached to the landing gear for takeoff and landing on water, 
and either extendable or fixed landing gear for takeoff and landing on 
land.
    ICAO Annex 16, Volume III means Volume III of Annex 16 to the 
Convention on International Civil Aviation.
    Maximum takeoff mass (MTOM) is the maximum allowable takeoff mass 
as stated in the approved certification basis for an airplane type 
design. Maximum takeoff mass is expressed in kilograms.
    Performance model is an analytical tool (or a method) validated 
using corrected flight test data that can be used to determine the 
specific air range values for calculating the fuel efficiency metric 
value.
    Reference geometric factor (RGF) is a non-dimensional number 
derived from a two-dimensional projection of the fuselage.
    Specific air range (SAR) is the distance an airplane travels per 
unit of fuel consumed. Specific air range is expressed in kilometers 
per kilogram of fuel.
    Subsonic means an airplane that has not been certificated under 
this title to exceed Mach 1 in normal operation.
    Type certificated maximum passenger seating capacity means the 
maximum number of passenger seats that may be installed on an airplane 
as listed on its type certificate data sheet, regardless of the actual 
number of seats installed on an individual airplane.

Sec.  38.4   Compatibility with airworthiness requirements.

    Unless otherwise approved by the FAA, an airplane used to 
demonstrate compliance with this part must meet all of the 
airworthiness requirements of this chapter required to establish the 
type certification basis of the airplane, for any condition under which 
compliance with this part is being demonstrated. Any procedure used to 
demonstrate compliance, and any flight crew information developed for 
demonstrating compliance with this part, must be consistent with the 
airworthiness requirements of this chapter that constitute the type 
certification basis of the airplane.

Sec.  38.5   Exemptions.

    A petition for exemption from any requirement of this part must be 
submitted to the Administrator in accordance with and meet the 
requirements of part 11 of this chapter. The FAA will consult with the 
EPA on each exemption petition before taking action.

Sec.  38.7   [Reserved]

Sec.  38.9   Relationship to other regulations.

    In accordance with certain provision of the Clean Air Act 
Amendments of 1970 (CAA) (42 U.S.C. 7571 et seq.), the United States 
Environmental Protection Agency (EPA) is authorized to set standards 
for aircraft engine emissions in the United States, while the FAA is 
authorized to insure compliance with those standards under a delegation 
from the Secretary of Transportation (49 CFR 1.47). The fuel efficiency 
limits in Sec.  38.17 are intended to be the same as that promulgated 
by the EPA in 40 CFR part 1030. Accordingly, if the EPA changes any 
regulation in 40 CFR part 1030 that corresponds with a regulation in 
this part, a certification applicant may request a waiver of those 
provisions as they appear in this part in order to comply with part 
1030. In addition, unless otherwise specified in this part, all 
terminology and abbreviations in this part that are defined in 40 CFR 
part 1030 have the meaning specified in part 1030.

Subpart B--Determining Fuel Efficiency for Subsonic Airplanes

Sec.  38.11   Fuel efficiency metric.

    For each airplane subject to this part, or to determine whether a 
modification makes an airplane subject to this part under the change 
criteria of Sec.  38.19, a fuel efficiency metric value must be 
calculated, using the following equation, rounded to three decimal 
places:
[GRAPHIC] [TIFF OMITTED] TP15JN22.001

Where:

The SAR is determined in accordance with Sec.  38.13, and the RGF is 
determined in accordance with Sec.  38.15. The fuel efficiency 
metric value is expressed in units of kilograms of fuel consumed per 
kilometer.

[[Page 36086]]

Sec.  38.13   Specific air range.

    (a) For each airplane subject to this part, the SAR of an airplane 
must be determined by either:
    (1) Direct flight test measurements.
    (2) Using a performance model that is:
    (i) Validated by actual SAR flight test data; and
    (ii) Approved by the FAA before any SAR calculations are made.
    (b) For the airplane model, establish a 1/SAR value at each of the 
following reference airplane masses:
    (1) High gross mass: 92 percent MTOM.
    (2) Low gross mass: (0.45 * MTOM) + (0.63 * (MTOM[supcaret]0.924)).
    (3) Mid gross mass: simple arithmetic average of high gross mass 
and low gross mass.
    (c) To obtain (1/SAR)avg as required to determine the 
fuel efficiency metric value described in Sec.  38.11, calculate the 
average of the three 1/SAR values described in paragraph (b) of this 
section. Do not include auxiliary power units in any 1/SAR calculation.
    (d) All determinations made under this section must be made in 
accordance with the procedures applicable to SAR as described in 
appendix A to this part.

Sec.  38.15   Reference geometric factor.

    For each airplane subject to this part, determine the airplane's 
non-dimensional RGF for the fuselage size of each airplane model, 
calculated as follows:
    (a) For an airplane with a single deck, determine the area of a 
surface (expressed in m[supcaret]2) bounded by the maximum width of the 
fuselage outer mold line projected to a flat plane parallel with the 
main deck floor and the forward and aft pressure bulkheads except for 
the crew cockpit zone.
    (b) For an airplane with more than one deck, determine the sum of 
the areas (expressed in m[supcaret]2) as follows:
    (1) The maximum width of the fuselage outer mold line, projected to 
a flat plane parallel with the main deck floor by the forward and aft 
pressure bulkheads except for any crew cockpit zone.
    (2) The maximum width of the fuselage outer mold line at or above 
each other deck floor, projected to a flat plane parallel with the 
additional deck floor by the forward and aft pressure bulkheads except 
for any crew cockpit zone.
    (c) Determine the non-dimensional RGF by dividing the area defined 
in paragraph (a) or (b) of this section by 1 m[supcaret]2.
    (d) All measurements and calculations used to determine the RGF of 
an airplane must be made in accordance with the procedures for 
determining RGF in section A38.3 of appendix A to this part.

Sec.  38.17   Fuel efficiency limits.

    (a) The fuel efficiency limits in this section are expressed as 
maximum permitted fuel efficiency metric values, as calculated under 
Sec.  38.11.
    (b) The fuel efficiency metric value of an airplane subject to this 
part may not exceed the following, rounded to three decimal places:

------------------------------------------------------------------------
                                                   The maximum permitted
For airplanes described in . .  With a MTOM . . .     fuel efficiency
               .                                   metric value is . . .
 
------------------------------------------------------------------------
(1) Section 38.1(a)(1) and (2)  5,700 < MTOM <=    10 (-
                                 60,000 kg.         2.73780+(0.681310*lo
                                                    g10(MTOM))+(-
                                                    0.0277861*(log10(MTO
                                                    M))[supcaret]2)).
(2) Section 38.1(a)(3)........  8,618 < MTOM <=    10 (-
                                 60,000 kg.         2.73780+(0.681310*lo
                                                    g10(MTOM))+(-
                                                    0.0277861*(log10(MTO
                                                    M))[supcaret]2)).
(3) Section 38.1(a)(1) and (3)  60,000 < MTOM <=   0.764.
                                 70,395 kg.
(4) Section 38.1(a)(1) and (3)  MTOM > 70,395 kg.  10 (-1.412742+(-
                                                    0.020517*log10(MTOM)
                                                    )+(0.0593831*(log10(
                                                    MTOM))[supcaret]2)).
(5) Section 38.1(a)(4) and (6)  5,700 < MTOM <=    10 (-
                                 60,000 kg.         2.57535+(0.609766*lo
                                                    g10(MTOM))+(-
                                                    0.0191302*(log10(MTO
                                                    M))[supcaret]2)).
(6) Section 38.1(a)(5) and (7)  8,618 < MTOM <=    10 (-
                                 60,000 kg.         2.57535+(0.609766*lo
                                                    g10(MTOM))+(-
                                                    0.0191302*(log10(MTO
                                                    M))[supcaret]2)).
(7) Section 38.1(a)(4) through  60,000 < MTOM <=   0.797.
 (7).                            70,107 kg.
(8) Section 38.1(a)(4) through  MTOM > 70,107 kg.  10 (-1.39353+(-
 (7).                                               0.020517*log10(MTOM)
                                                    )+(0.0593831*(log10(
                                                    MTOM))[supcaret]2)).
------------------------------------------------------------------------

Sec.  38.19   Change criteria.

    (a) For an airplane that has been shown to comply with Sec.  38.17, 
any subsequent version of that airplane must demonstrate compliance 
with Sec.  38.17 if the subsequent version incorporates a modification 
that either increases:
    (1) The maximum takeoff mass; or
    (2) The fuel efficiency metric value by more than:
    (i) For airplanes with a MTOM greater than or equal to 5,700 kg, 
the value decreases linearly from 1.35 to 0.75 percent for an airplane 
with a MTOM of 60,000 kg.
    (ii) For airplanes with a MTOM greater than or equal to 60,000 kg, 
the value decreases linearly from 0.75 to 0.70 percent for airplanes 
with a MTOM of 600,000 kg.
    (iii) For airplanes with a MTOM greater than or equal to 600,000 
kg, the value is 0.70 percent.
    (b) For an airplane that has been shown to comply with Sec.  38.17, 
and for any subsequent version of that airplane that incorporates 
modifications that do not increase the MTOM or the fuel efficiency 
metric value in excess of the levels shown in this paragraph (b), the 
fuel efficiency metric value of the modified airplane may be reported 
to be the same as the value of the prior version.
    (c) For an airplane that meets the criteria of Sec.  38.1(a)(4) or 
(5), on or after January 1, 2023, and before January 1, 2028, the 
airplane must demonstrate compliance with Sec.  38.17 if it 
incorporates any modification that increases the fuel efficiency metric 
value by more than 1.5 percent from the prior version of the airplane.

Sec.  38.21   Approval before compliance testing.

    All procedures, weights, configurations, and other information or 
data that are used to establish a fuel efficiency level required by 
this part or in any appendix to this part (including any equivalent 
procedures) must be approved by the FAA prior to use in certification 
tests intended to demonstrate compliance with this part.

Sec.  38.23   Manual information and limitations.

    (a) Information in manuals. The following information must be 
included in any FAA-approved section of a FAA-approved Airplane Flight 
Manual or combination of approved manual material:
    (1) Fuel efficiency level established during type certification; 
and
    (2) Maximum takeoff mass at which fuel efficiency level was 
established.
    (b) Limitation. If the fuel efficiency of an airplane is 
established at a weight (mass) that is less than the maximum 
certificated takeoff weight (mass) used to establish the airworthiness 
of the airplane under this chapter, the lower weight (mass) becomes an 
operating limitation of the airplane and that limitation must be 
included in the limitations section of any FAA-approved manual.

Appendix A to Part 38--Determination of Airplane Fuel Efficiency Metric 
Value

Sec.
A38.1 Introduction

[[Page 36087]]

A38.2 Reference Specifications for SAR Flight Tests
A38.3 Determination of Reference Geometric Factor (RGF)
A38.4 Certification Test Specifications
A38.5 Measurement of Specific Air Range
A38.6 Submission of Certification Data to the FAA

A38.1 Introduction

    A38.1.1 This appendix describes the processes and procedures for 
determining the fuel efficiency metric value for an airplane subject 
to this part.

A38.1.2 Methods for Determining Specific Air Range (SAR)

    A38.1.2.1 SAR may be determined by either--
    A38.1.2.1.1 Direct flight test measurement at the SAR test 
points, including any corrections of test data to reference 
specifications; or
    A38.1.2.1.2 Use of a performance model.
    A38.1.2.2 For any determination made under section A38.1.2.1.1 
of this appendix, the SAR flight test data must have been acquired 
in accordance with the procedures defined in this appendix and 
approved by the FAA.
    A38.1.2.3 For any determination made under section A38.1.2.1.2 
of this appendix, the performance model must:
    A38.1.2.3.1 Be verified that the model produces the values that 
are the same as FAA-approved SAR flight test data.
    A38.1.2.3.2 Include a detailed description of any test and 
analysis method and any algorithm used so as to allow evaluation by 
the FAA; and
    A38.1.2.3.4 Be approved by the FAA before use.

A38.2 Reference Specifications for SAR Flight Tests

    A38.2.1 The following reference specifications must be 
established when determining SAR values for an airplane. No 
reference specification may exceed any airworthiness limit approved 
for the airplane under this chapter. See section A38.5 of this 
appendix for further information.
    A38.2.1.1 Reference specifications at the airplane level:
    A38.2.1.1.1 Airplane at the reference masses listed in Sec.  
38.13(b);
    A38.2.1.1.2 A combination of altitude and airspeed selected by 
the applicant;
    A38.2.1.1.3 Airplane in steady, unaccelerating, straight and 
level flight;
    A38.2.1.1.4 Airplane in longitudinal and lateral trim;
    A38.2.1.1.5 Airplane gravitational acceleration when travelling 
in the direction of true North in still air at the reference 
altitude and a geodetic latitude of 45.5 degrees, based on 
g0 (g0 is 9.80665 m/s2, which is 
the standard acceleration due to gravity at sea level and a geodetic 
latitude of 45.5 degrees);
    A38.2.1.1.6 A reference airplane center of gravity (CG) position 
selected by the applicant to be representative of a mid-CG point 
relevant to design cruise performance at each of the three reference 
airplane masses; and
    A38.2.1.1.7 A wing structural loading condition defined by the 
applicant that is representative of operations conducted in 
accordance with the airplane's maximum payload capability.
    A38.2.1.2 Reference specifications at the engine level:
    A38.2.1.2.1 Electrical and mechanical power extraction and bleed 
flow relevant to design cruise performance, as selected by the 
applicant;
    Note.--Power extraction and bleed flow attributable to the use 
of optional equipment such as passenger entertainment systems need 
not be included.
    A38.2.1.2.2 Engine stability bleeds operating according to the 
manufacturer's normal schedule for the engine; and
    A38.2.1.2.3 Engines with at least 15 cycles or 50 engine flight 
hours.
    A38.2.1.3 Other reference specifications:
    A38.2.1.3.1 ICAO standard day atmosphere (Doc 7488/3, 3rd 
edition 1993, titled ``Manual of the ICAO Standard Atmosphere 
(extended to 80 kilometres (262 500 feet))'')
    A38.2.1.3.2 Fuel lower heating value equal to 43.217 MJ/kg (18 
580 BTU/lb);
    A38.2.2 If any test conditions are not the same as the reference 
specifications of this appendix, the test conditions must be 
corrected to the reference specifications as described in section 
A38.5 of this appendix.

A38.3 Determination of Reference Geometric Factor (RGF)

    A38.3.1 This section provides additional information for 
determining the RGF, as required by Sec.  38.15.
    A38.3.2 The area that defines RGF includes all pressurized space 
on a single or multiple decks including aisles, assist spaces, 
passageways, stairwells and areas that can accommodate cargo or 
auxiliary fuel containers. It does not include permanent integrated 
fuel tanks within the cabin, or any unpressurized fairings, crew 
rest or work areas, or cargo areas that are not on the main or upper 
deck (e.g., `loft' or under floor areas). RGF does not include the 
cockpit crew zone.
    A38.3.3 The aft boundary to be used for calculating RGF is the 
aft pressure bulkhead. The forward boundary is the forward pressure 
bulkhead, not including the cockpit crew zone.
    A38.3.4 Areas that are accessible to both crew and passengers 
are not considered part of the cockpit crew zone. For an airplane 
that has a cockpit door, the aft boundary of the cockpit crew zone 
is the plane of the cockpit door. For an airplane that has no 
cockpit door, or has optional interior configurations that include 
different locations of the cockpit door, the aft boundary is 
determined by the configuration that provides the smallest available 
cockpit crew zone. For airplanes certificated for single-pilot 
operation, the cockpit crew zone is measured as half the width of 
the cockpit.
    A38.3.5 Figures A38-1 and A38-2 of this appendix provide a 
notional view of the RGF boundary conditions.
BILLING CODE 4910-13-P

[[Page 36088]]

[GRAPHIC] [TIFF OMITTED] TP15JN22.002

[GRAPHIC] [TIFF OMITTED] TP15JN22.003

[[Page 36089]]

BILLING CODE 4910-13-C

A38.4 Certification Test Specifications

    A38.4.1 Certification Test Specifications. This section 
prescribes the specifications under which an applicant must conduct 
SAR certification tests.
    A38.4.2 Flight Test Procedures
    A38.4.2.1 Before a Test Flight. The test flight procedures must 
include the following elements and must be approved by the FAA 
before any test flight is conducted:
    A38.4.2.1.1 Airplane conformity. The test airplane must conform 
to the critical configuration of the type design for which 
certification is sought.
    A38.4.2.1.2 Airplane weight. The weight and balance of the test 
airplane must be established prior to the test flight, including any 
changes in weight that occur after the airplane is weighed and 
before the flight is conducted.
    A38.4.2.1.3 Fuel. The fuel used for each flight test must meet 
the specification defined in either ASTM D1655-15 (entitled 
``Standard Specification for Aviation Turbine Fuels''), Defense 
Standard 91-91, Issue 7, Amendment 3 (entitled ``Turbine Fuel, 
Kerosene Type, Jet A-1''), or as approved by FAA.
    A38.4.2.1.4 Fuel lower heating value. The lower heating value of 
the fuel used on a test flight must be determined from a sample of 
fuel used for the test flight. The lower heating value of the fuel 
sample must be used to correct measured data to reference 
specifications. The determination of lower heating value and the 
correction to reference specifications are subject to approval by 
the FAA.
    A38.4.2.1.4.1 The fuel lower heating value may be determined in 
accordance with ASTM specification D4809-13 ``Standard Test Method 
for Heat of Combustion of Liquid Hydrocarbon Fuels by Bomb 
Calorimeter (Precision Method)'', or as approved by the FAA.
    A38.4.2.1.4.2 The fuel sample may be representative of the fuel 
used for each flight test and may not have variations.
    A38.4.2.1.5 Fuel specific gravity and viscosity. When volumetric 
fuel flow meters are used, the specific gravity and viscosity of the 
fuel used on a test flight must be determined from a sample of fuel 
used for the test flight.
    A38.4.2.1.5.1 The fuel specific gravity may be determined in 
accordance with ASTM specification D4052-11 ``Standard Test Method 
for Density and Relative Density of Liquids by Digital Density 
Meter'', or as approved by FAA.
    A38.4.2.1.5.2 The fuel kinematic viscosity may be determined in 
accordance with ASTM specification D445-15 (entitled ``Standard Test 
Method for Kinematic Viscosity of Transparent and Opaque Liquids 
(and Calculation of Dynamic Viscosity)''), or as approved by FAA.
    A38.4.2.2 Flight Test Configurations and Test Condition 
Stability. An applicant must conduct each flight test in accordance 
with the flight test configurations and the stability conditions as 
follows:
    A38.4.2.2.1 Flight Test Configuration. The following 
configurations must be maintained during each flight used to gather 
data for determining SAR values:
    A38.4.2.2.1.1 To the extent that is practicable, the airplane is 
flown at constant pressure altitude and constant heading along 
isobars;
    A38.4.2.2.1.2 The engine thrust/power setting is stable for 
unaccelerating level flight;
    A38.4.2.2.1.3 The airplane is flown as close as practicable to 
the reference specifications to minimize the magnitude of any 
correction;
    A38.4.2.2.1.4 There are no changes in trim or engine power/
thrust settings, engine stability and handling bleeds, or electrical 
and mechanical power extraction (including bleed flow); and
    A38.4.2.2.1.5 There is no unnecessary movement of on-board 
personnel.
    A38.4.2.2.2 Test Condition Stability. To obtain a valid SAR 
measurement, the following conditions must be maintained during each 
test flight, including the indicated tolerances for at least 1 
minute while SAR data is acquired:
    A38.4.2.2.2.1 Mach number within 0.005;
    A38.4.2.2.2.2 Ambient temperature within 1 [deg]C;
    A38.4.2.2.2.3 Heading within 3 degrees;
    A38.4.2.2.2.4 Track within 3 degrees;
    A38.4.2.2.2.5 Drift angle less than 3 degrees;
    A38.4.2.2.2.6 Ground speed within 3.7 km/h (2 kt);
    A38.4.2.2.2.7 Difference in ground speed at the beginning of the 
SAR measurement from the ground speed at the end of the SAR 
measurement within 2.8 km/h/min (1.5 kt/
min); and
    A38.4.2.2.2.8 Pressure altitude within 23 m (75 ft).
    A38.4.2.2.3 Alternatives to the stable test condition criteria 
of section A38.4.2.2.2 of this appendix may be used provided that 
stability is sufficiently demonstrated to the FAA.
    A38.4.2.2.4 Data obtained at test points that do not meet the 
stability criteria of section A38.4.2.2.2 may be acceptable as an 
equivalent procedure, subject to FAA approval.
    A38.4.2.2.5 SAR measurements at the test points must be 
separated by either:
    A38.4.2.2.5.1 Two minutes; or
    A38.4.2.2.5.2 An exceedance of one or more of the stability 
criteria limits described in A38.4.2.2.2.

A38.4.2.3 Verification of Airplane Mass at Test Conditions

    A38.4.2.3.1 The procedure for determining the mass of the 
airplane at each test condition must be approved by the FAA.
    A38.4.2.3.2 The mass of the airplane during a flight test is 
determined by subtracting the fuel used from the mass of the 
airplane at the start of the test flight. The accuracy of the 
determination of the fuel used must be verified by:
    A38.4.2.3.2.1 Weighing the test airplane on calibrated scales 
before and after the SAR test flight; or
    A38.4.2.3.2.2 Weighing the test airplane before and after 
another test flight that included a cruise segment, provided that 
flight occurs within one week or 50 flight hours (at the option of 
the applicant) of the SAR test flight and using the same, unaltered 
fuel flow meters.

A38.5 Measurement of Specific Air Range

    A38.5.1 Measurement System
    A38.5.1.1 The following parameters must be recorded at a minimum 
sampling rate of 1 Hertz (cycle per second):
    A38.5.1.1.1 Airspeed;
    A38.5.1.1.2 Ground speed;
    A38.5.1.1.3 True airspeed;
    A38.5.1.1.4 Fuel flow;
    A38.5.1.1.5 Engine power setting;
    A38.5.1.1.6 Pressure altitude;
    A38.5.1.1.7 Temperature;
    A38.5.1.1.8 Heading;
    A38.5.1.1.9 Track; and
    A38.5.1.1.10 Fuel used (for the determination of gross mass and 
CG position).
    A38.5.1.2 The following parameters must be recorded:
    A38.5.1.2.1 Latitude;
    A38.5.1.2.2 Engine bleed positions and power off-takes; and
    A38.5.1.2.3 Power extraction (electrical and mechanical load).
    A38.5.1.3 The value of each parameter used for the determination 
of SAR (except for ground speed) is the simple arithmetic average of 
the measured values for that parameter obtained throughout the 
stable test condition described in section A38.4.2.2.2 of this 
appendix.
    A38.5.1.4 For ground speed, the value is the rate of change of 
ground speed during the SAR test measurement. The rate of change of 
ground speed during the SAR measurement must be used to evaluate and 
correct any acceleration or deceleration that might occur during the 
SAR measurement.
    A38.5.1.5 Each measurement device must have sufficient 
resolution to determine that the stability of a parameter defined in 
section A38.4.2.2.2 of this appendix is maintained during SAR 
measurement.
    A38.5.1.6 The SAR measurement system consists of the combined 
instruments and devices, and any associated procedures, used to 
acquire the following parameters necessary to determine SAR:
    A38.5.1.6.1 Fuel flow;
    A38.5.1.6.2 Mach number;
    A38.5.1.6.3 Altitude;
    A38.5.1.6.4 Airplane mass;
    A38.5.1.6.5 Ground speed;
    A38.5.1.6.6 Outside air temperature;
    A38.5.1.6.7 Fuel lower heating value; and
    A38.5.1.6.8 CG.
    A38.5.1.7 The SAR value is affected by the accuracy of each 
element that comprises the SAR measurement system. The cumulative 
error associated with the SAR measurement system is defined as the 
root sum of squares (RSS) of the individual accuracies.
    A38.5.1.8 If the absolute value of the cumulative error of the 
overall SAR measurement system is greater than 1.5 percent, a 
penalty equal to the amount that the RSS value exceeds 1.5 percent 
must be applied to the SAR value that has been corrected to 
reference specifications (see

[[Page 36090]]

section A38.5.2 of this appendix). If the absolute value of the 
cumulative error of the overall SAR measurement system is less than 
or equal to 1.5 percent, no penalty will be applied.
    A38.5.2 Calculation of Specific Air Range from Measured Data
    A38.5.2.1 Calculating SAR. SAR must be calculated using the 
following equation: SAR = TAS/Wf where TAS is the true 
airspeed and Wf is total airplane fuel flow.
    A38.5.2.2 Correcting Measured SAR Values to Reference 
Specifications
    A38.5.2.2.1 The measured SAR values must be corrected to the 
reference specifications listed in A38.2 of this appendix. Unless 
otherwise approved by the FAA, corrections to reference 
specifications must be applied for each of the following measured 
parameters:
    A38.5.2.2.1.1 Acceleration/deceleration (energy). Drag 
determination is based on an assumption of steady, unaccelerating 
flight. Acceleration or deceleration occurring during a test 
condition affects the assessed drag level. The reference 
specification is in section A38.2.1.1.3 of this appendix.
    A38.5.2.2.1.2 Aeroelastics. Wing aeroelasticity may cause a 
variation in drag as a function of airplane wing mass distribution. 
Airplane wing mass distribution will be affected by the fuel load 
distribution in the wings and the presence of any external stores. 
The reference specification is in section A38.2.1.1.7 of this 
appendix.
    A38.5.2.2.1.3 Altitude. The altitude at which the airplane is 
flown affects the fuel flow. The reference specification is in 
section A38.2.1.1.2 of this appendix.
    A38.5.2.2.1.4 Apparent gravity. Acceleration, caused by the 
local effect of gravity, and inertia, affect the test weight of the 
airplane. The apparent gravity at the test conditions varies with 
latitude, altitude, ground speed, and direction of motion relative 
to the Earth's axis. The reference gravitational acceleration is the 
gravitational acceleration for the airplane travelling in the 
direction of true North in still air at the reference altitude, a 
geodetic latitude of 45.5 degrees, and based on g0 (see 
section A38.2.1.1.5 of this appendix).
    A38.5.2.2.1.5 CG position. The position of the airplane CG 
affects the drag due to longitudinal trim. The reference 
specification is in section A38.2.1.1.6 of this appendix.
    A38.5.2.2.1.6 Electrical and mechanical power extraction and 
bleed flow. Electrical and mechanical power extraction, and bleed 
flow affect the fuel flow. The reference specifications are in 
sections A38.2.1.2.1 and A38.2.1.2.2 of this appendix.
    A38.5.2.2.1.7 Engine deterioration level. The requirement in 
section A38.2.1.2.3 of this appendix addresses the minimum 
deterioration of an engine that is used to determine SAR. Since 
engine deterioration is rapid when an engine is new, when used for 
SAR determination:
    A38.5.2.2.1.7.1 Subject to FAA approval, an engine having less 
deterioration than the reference deterioration level in section 
A38.2.1.2.3 of this appendix must correct the fuel flow to the 
reference deterioration using an approved method.
    A38.5.2.2.1.7.2 An engine with greater deterioration than the 
reference deterioration level in section A38.2.1.2.3 of this 
appendix may be used, and no correction is permitted.
    A38.5.2.2.1.8 Fuel lower heating value. The fuel lower heating 
value defines the energy content of the fuel. The lower heating 
value directly affects the fuel flow at a given test condition. The 
reference specification is in section A38.2.1.3.2 of this appendix.
    A38.5.2.2.1.9 Reynolds number. The Reynolds number affects 
airplane drag. For a given test condition the Reynolds number is a 
function of the density and viscosity of air at the test altitude 
and temperature. The reference Reynolds number is derived from the 
density and viscosity of air from the ICAO standard atmosphere at 
the reference altitude (see sections A38.2.1.1.2 and A38.2.1.3.1 of 
this appendix).
    A38.5.2.2.1.10 Temperature. The ambient temperature affects the 
fuel flow. The reference temperature is the standard day temperature 
from the ICAO standard atmosphere at the reference altitude (see 
section A38.2.1.3.1 of this appendix).
    Note.--Post-flight data analysis includes the correction of 
measured data for data acquisition hardware response characteristics 
(e.g. system latency, lag, offset, buffering, etc.).
    A38.5.2.2.2 Correction methods are subject to the approval of 
the FAA.
    A38.5.2.3 Using Specific Air Range to Determine the Fuel 
Efficiency Metric Value
    A38.5.2.3.1 Calculate the SAR values for each of the three 
reference masses as described in Sec.  38.13, including any 
corrections to reference specifications, as required under this 
part. The final SAR value for each reference mass is the simple 
arithmetic average of all valid test points at the appropriate gross 
mass, or derived from a validated performance model. No data 
acquired from a valid test point may be omitted unless approved by 
the FAA.
    A38.5.2.3.2 When an FAA-approved performance model is used, 
extrapolations to aircraft masses other than those tested may be 
approved when such extrapolations are consistent with accepted 
airworthiness practices. Since a performance model must be based on 
data covering an adequate range of lift coefficient, Mach number, 
and thrust specific fuel consumption, no extrapolation of those 
parameters is permitted.
    A38.5.3 Validity of Results
    A38.5.3.1 A 90 percent confidence interval must be calculated 
for each of the SAR values at the three reference masses.
    A38.5.3.2 If the 90 percent confidence interval of the SAR value 
at any of the three reference airplane masses--
    A38.5.3.2.1 Is less than or equal to 1.5 percent, 
the SAR value may be used.
    A38.5.3.2.2 Exceeds 1.5 percent, a penalty equal to 
the amount that the 90 percent confidence interval exceeds 1.5 percent must be applied to the SAR value, as approved by 
the FAA.
    A38.5.3.3 If clustered data is acquired separately for each of 
the three gross mass reference points, the minimum sample size 
acceptable for each of the three gross mass SAR values is six.
    A38.5.3.4 If SAR data is collected over a range of masses, the 
minimum sample size is 12 and the 90 percent confidence interval is 
calculated for the mean regression line through the data.

A38.6 Submission of Certification Data to the FAA

    The following information must be provided to the FAA in the 
certification test report for each airplane type and model for which 
fuel efficiency certification under this part is sought.
    A38.6.1 General Information
    A38.6.1.1 Designation of the airplane type and model:
    A38.6.1.2 Configuration of the airplane as required in Sec.  
38.23(a)(3), including CG range, number and type designation of 
engines and, if fitted, propellers, and any modifications or non-
standard equipment expected to affect the fuel efficiency 
characteristics;
    A38.6.1.3 MTOM used for certification under this part;
    A38.6.1.4 All dimensions needed for calculation of RGF; and
    A38.6.1.5 Serial number of each airplane used to establish fuel 
efficiency certification in accordance with this part.
    A38.6.2 Reference Specifications. The reference specifications 
used to determine any SAR value as described in section A38.2 of 
this appendix.
    A38.6.3 Test Data. The following measured test data, including 
any corrections for instrumentation characteristics, must be 
provided for each of the test measurement points used to calculate 
the SAR values for each of the reference masses defined in Sec.  
38.13(b):
    A38.6.3.1 Airspeed, ground speed and true airspeed;
    A38.6.3.2 Fuel flow;
    A38.6.3.3 Pressure altitude;
    A38.6.3.4 Static air temperature;
    A38.6.3.5 Airplane gross mass and CG for each test point;
    A38.6.3.6 Levels of electrical and mechanical power extraction 
and bleed flow;
    A38.6.3.7 Engine performance:
    A38.6.3.7.1 For jet airplanes, engine power setting; or
    A38.6.3.7.2 For propeller-driven airplanes, shaft horsepower or 
engine torque, and propeller rotational speed;
    A38.6.3.8 Fuel lower heating value;
    A38.6.3.9 When volumetric fuel flow meters are used, fuel 
specific gravity and kinematic viscosity (see section A38.5.2.2.1.8 
of this appendix);
    A38.6.3.10 The cumulative error (RSS) of the overall measurement 
system (see section A38.5.1.7 of this appendix);
    A38.6.3.11 Heading, track and latitude;
    A38.6.3.12 Stability criteria (see section A38.4.2.2.2 of this 
appendix); and
    A38.6.3.13 Description of the instruments and devices used to 
acquire the data needed for the determination of SAR, and the 
individual accuracies of the equipment relevant to their effect on 
SAR (see sections A38.5.1.6 and A38.5.1.7 of this appendix).
    A38.6.4 Calculations and Corrections of SAR Test Data to 
Reference Specifications. The measured SAR values, corrections to 
the reference specifications and corrected SAR values must be 
provided for each of the test measurement points defined in Sec.  
38.13(b).
    A38.6.5 Calculated Values. The following values must be provided 
for each airplane

[[Page 36091]]

used to establish fuel efficiency certification in accordance with 
this part:
    A38.6.5.1 SAR (km/kg) for each reference airplane mass and the 
associated 90 percent confidence interval;
    A38.6.5.2 Average of the 1/SAR values;
    A38.6.5.3 RGF; and
    A38.6.5.4 Fuel efficiency metric value.

PART 121--OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL 
OPERATIONS

0
12. The authority citation for part 121 continues to read as follows:

    Authority:  49 U.S.C. 106(f), 106(g), 40103, 40113, 40119, 
41706, 42301 preceding note added by Public Law 112-95, sec. 412, 
126 Stat. 89, 44101, 44701-44702, 44705, 44709-44711, 44713, 44716-
44717, 44722, 44729, 44732; 46105; Public Law 111-216, 124 Stat. 
2348 (49 U.S.C. 44701 note); Public Law 112-95 126 Stat 62 (49 
U.S.C. 44732 note).

0
13. Amend Sec.  121.141 by revising paragraph (b) introductory text to 
read as follows:

Sec.  121.141   Airplane flight manual.

* * * * *
    (b) In each airplane required to have an airplane flight manual in 
paragraph (a) of this section, the certificate holder shall carry 
either the manual required by Sec.  121.133, if it contains the 
information required for the applicable flight manual and this 
information is clearly identified as flight manual requirements, or an 
approved Airplane Manual. If the certificate holder elects to carry the 
manual required by Sec.  121.133, the certificate holder must revise 
the operating procedures sections and modify the presentation of 
performance data, except for the information required by Sec.  38.23 of 
this chapter identifying compliance with the fuel efficiency 
requirements of part 38 of this chapter, from the applicable flight 
manual if the revised operating procedures and modified performance 
data presentation are--
* * * * *

PART 125--CERTIFICATION AND OPERATIONS: AIRPLANES HAVING A SEATING 
CAPACITY OF 20 OR MORE PASSENGERS OR A MAXIMUM PAYLOAD CAPACITY OF 
6,000 POUNDS OR MORE; AND RULES GOVERNING PERSONS ON BOARD SUCH 
AIRCRAFT

0
14. The authority citation for part 125 continues to read as follows:

    Authority: 49 U.S.C. 106(f), 106(g), 40113, 44701-44702, 44705, 
44710-44711, 44713, 44716-44717, 44722.
0
15. Amend Sec.  125.75 by revising paragraph (b) to read as follows:

Sec.  125.75   Airplane flight manual.

* * * * *
    (b) Each certificate holder shall carry the approved Airplane 
Flight Manual or the approved equivalent aboard each airplane it 
operates. A certificate holder may elect to carry a combination of the 
manuals required by this section and Sec.  125.71. If it so elects, the 
certificate holder may revise the operating procedures sections and 
modify the presentation of performance from the applicable Airplane 
Flight Manual if the revised operating procedures and modified 
performance data presentation are approved by the Administrator. Any 
approved equivalent must include the information required by Sec.  
38.23 of this chapter identifying compliance with the fuel efficiency 
requirements of part 38 of this chapter.

    Issued under authority provided in 42 U.S.C 4321 et seq., 7572, 
49 U.S.C. 106(f), 40113, 44701-44702, 44703, and 44704 in 
Washington, DC.
Kevin Welsh,
Executive Director, Office of Environment and Energy.
[FR Doc. 2022-11556 Filed 6-14-22; 8:45 am]
BILLING CODE 4910-13-P