as the standard for limiting human injuries from the energy a small
unmanned aircraft transfers upon impact. This discussion also
summarizes the sources of relevant information the FAA considered and
will continue to monitor.

(a) International Activities and Ongoing Research
    Since the ARC, the FAA has carefully examined additional
information with regard to injury risks and energy thresholds. The
European Aviation Safety Agency (EASA) published a prototype regulation
in August 2016, followed by a Notice of Proposed Amendment (NPA) on May
4, 2017.\57\ The NPA introduces categories of permissible small UAS
operations based on maximum takeoff masses; the ``open'' category is
most permissive, and proposes a subcategory to permit small UAS
operations over uninvolved people, but not over assemblies of people,
as long as the aircraft does not exceed 250 grams maximum takeoff mass
and does not have sharp edges. These aircraft would be limited to 50
meters (approximately 164 feet) above ground level (AGL) and eligible
for operations that remote pilots of any age could conduct, provided
they have educational materials to ensure competence. Other
commercially built small unmanned aircraft would be permitted to
operate over uninvolved people if they fulfill several product safety
requirements, including either an energy transmitted to the human body
less than 80 joules upon impact or a maximum takeoff mass, including
payload, of less than 900 grams and a maximum cruising speed of 18
meters per second. These other aircraft would also be subject to the
limit of 50 meters AGL unless the pilots conducting the operations take
online training with a test, in which case they could conduct
operations up to 120 meters AGL. The NPA proposes allowing other
operations that do not fulfill these criteria, as long as they do not
operate directly over uninvolved people and comply with certain
operational restrictions.\58\
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    \57\ Introduction of a Regulatory Framework for the Operation of
Drones--Unmanned Aircraft System Operations in the Open and Specific
Category, Notice of Proposed Amendment 2017-05, available at https://www.easa.europa.eu/system/files/dfu/NPA%202017-05%20%28A%29_0.pdf.
    \58\ Similar to the FAA, EASA may consider ongoing research as
it determines the suitability of energy thresholds and the
likelihood of human injury in attempting to categorize the risk
small UAS operations over people may present.
---------------------------------------------------------------------------

    In the NPA, EASA also states it relied on the Joint Authorities for
Rulemaking on Unmanned Systems (JARUS) concept that identifies three
categories based on several factors concerning the intended operations.
JARUS is a collaborative group of international participants that
develop guidance material to assist governing authorities in
promulgating standards. The FAA participates in JARUS in developing
such materials, and has considered JARUS activities and proposed
policies in furtherance of the FAA's goal of integrating UAS safely
into the NAS. In this regard, the FAA continues to contribute to JARUS
and its stated mission to develop a regulatory framework for unmanned
aircraft operations and proposals for the regulation of operations the
member states would consider ``low-risk.''
    Since 2015, the FAA has collaborated with the academic community
and its affiliates by fostering cooperative research and developing
intellectual capabilities of primary interest to the FAA and the UAS
community, through the work of the UAS Center of Excellence under the
Alliance for System Safety of UAS through Research Excellence (ASSURE).
Recent research from one ASSURE study has informed the FAA's decision-
making concerning operations of small unmanned aircraft over
people.\59\ The results of the study corroborate the FAA's impact
severity estimates that form the basis for this rule, in that the
ASSURE researchers used kinetic energy upon impact as a basis for
estimating the severity of injury a small UAS impacting a person
causes.
---------------------------------------------------------------------------

    \59\ Arterburn, et al., FAA UAS Center of Excellence Task A4:
UAS Ground Collision Severity Evaluation: Revision 2 (Apr. 28, 2017)
(hereinafter ``A4 Report''). The final report underwent peer review
of researchers from FAA, the National Aeronautics and Space
Administration, and industry participants. The report is available
in the docket for this rulemaking.
---------------------------------------------------------------------------

    This research substantiates the need for the development of
manufacturer standards that will address how to measure the potential
for human injury that results from small UAS impacts with a person. In
particular, given the significant variability in the impact dynamics
and amounts of energy transfer that the report identified, the ASSURE
research indicates addressing impact dynamics, aerodynamic drag, the
shape and material properties of the small UAS, and other potential
factors, will be persuasive aspects to consider for creating standards
that ensure safety. The A4 Report also highlights the necessity for
safer blade designs or restrictions that could limit the effects of
exposed rotating parts.
(b) FAA Proposal
    This proposed rule would use the term ``safety level'' in the
requirement applicable to means of compliance: In particular,
applicants that submit means of compliance for FAA acceptance must show
the means of compliance would achieve the safety level the proposed
standards reach. This safety level refers to the limitation of injury
severity caused by transfers of kinetic energy, exposed rotating parts,
or safety defects. With regard to the impact kinetic energy limitations
in this rule, the small unmanned aircraft must not be capable of
causing an injury to a human being that is more severe than injury that
would result from an impact kinetic energy transfer of 11 ft-lbs
(Category 2) or 25 ft-lbs (Category 3) from a rigid object. In
addition, this proposed rule would prohibit small UAS eligible for
operations in either Category 2 or Category 3 from having exposed
rotating parts that could lacerate human skin and from having any
safety defects. Finally, to establish an appropriate safety level, this
rule would also require certain operational limitations for Category 3
operations. Consistent with the ARC recommendation, this rule proposes
a performance-based standard that the FAA believes is equivalent to
reducing the likelihood of causing a certain level of expected injury.
(1) Safety Level
    This proposed rule's establishment of a safety level that, in part,
limits the effects of kinetic energy upon impact arises from the FAA's
consideration of the AIS as a means of establishing the acceptable
injury thresholds. In the Supplemental NPRM (SNPRM) titled ``Licensing
and Safety Requirements for Launch,'' the FAA discussed the concept of
levels of injury risk from impacts with inert debris resulting from
commercial space launches.\60\ In determining the acceptable level of
risk of injury from inert debris, the FAA stated: ``[o]ne must note
that not every impact of debris at 11 ft-lbs or greater would
necessarily result in a casualty. The probability of casualty due to
such an impact is further dependent on a number of other factors
specific to the debris and the impact scenario.'' \61\ The FAA
considered the concept of the risk of injury from inert debris in
proposing standards for small unmanned aircraft, as explained below.
---------------------------------------------------------------------------

    \60\ See Licensing and Safety Requirements for Launch,
Supplemental Notice of Proposed Rulemaking, 67 FR 49456 (July 30,
2002), which the FAA finalized on August 25, 2006. 71 FR 50508.
    \61\ 67 FR at 49465.
---------------------------------------------------------------------------

(a) Transfer of Energy From Rigid Object
    This rule proposes a performance-based standard that includes the
term ``rigid object'' with regard to the transfer of energy. For
purposes of this proposed rule, the FAA considers a rigid object to be
a body on which the distance between two points never changes,
notwithstanding the amount of force applied on it. Such a definition,
therefore, includes a body that does not

deform under the influence of forces. The FAA is fully aware that many
factors affect the transfer of kinetic energy. For example, elasticity,
impact dynamics, impact orientation, and a variety of other factors
would ostensibly reduce the amount of energy the object actually
transfers. Research suggests a rigid object impacts someone with more
kinetic energy and therefore could cause injuries more severe than
those a small unmanned aircraft would cause upon impact.
    The A4 Report from ASSURE suggests a vertical drop test that
measures kinetic energy upon impact alone is not the most accurate
means of estimating injury that occurs as a result of the energy
transfer. The ASSURE research also proposed alternatives to measuring
injury that would result from a small unmanned aircraft that impacts a
person. The study suggested other test methods that account for the
design configuration and material properties of the small UAS may
measure the severity of blunt trauma that results from an impact more
accurately than kinetic energy measurements alone. ASSURE is conducting
further research on alternative methodologies as indicators of the
severity of injuries from impacts with small unmanned aircraft.
    The study strongly suggests the transfer of energy from a small
unmanned aircraft, while difficult to measure, is unlikely to reach 100
percent of the total kinetic energy. In this regard, the study states:

    The energy that is directly absorbed is the difference between
the transferred energy and the change in kinetic energy of the
impacted object. Absorbed energy is a function of the deformation of
the impacted mass and the associated damping caused by the materials
from which the impacted object is manufactured.\62\
---------------------------------------------------------------------------

    \62\ A4 Report at 32-33.

    The study indicates deformation and absorption of energy are
influential factors to consider when measuring energy from a small
unmanned aircraft falling on a person because ``[i]n the case of a
person being hit by a UAS, deformation and absorbed energy contribute
to the injuries associated with blunt force trauma.'' \63\
---------------------------------------------------------------------------

    \63\ Id.
---------------------------------------------------------------------------

    The study attempted to theorize the likelihood of injury that would
result from an impact with a small unmanned aircraft as compared to an
impact with blunt, dense objects such as a ball of steel and a block of
wood.\64\ The risk of a serious injury from such objects varies, given
the frangibility and dense nature of the object, among other factors.
The research conducted impact testing of each of these objects and
established that the transfer of energy from these objects varies
greatly due to design characteristics and the variation of materials
that compose the objects. The study showed the transfer of energy from
a rigid object was more likely to cause injury than the energy
transferred from an object that is less rigid, such as a small unmanned
aircraft of the same weight. The FAA intends the practice of comparing
the energy transferred from a rigid object to the transfer of energy
from a small unmanned aircraft will permit manufacturers, likely by way
of an industry consensus standard, to design small unmanned aircraft
that fulfill the safety levels the FAA proposes in this rule.
Ultimately, the FAA intends its inclusion of the term ``rigid object''
to provide flexibility applicable to each small unmanned aircraft
design, based on limiting human injury caused by the transfer of
energy.
---------------------------------------------------------------------------

    \64\ A-4 Report at 84.
---------------------------------------------------------------------------

    Along with the inclusion of the term ``rigid object'' in the
standards that would govern the qualification of small UAS eligible to
conduct operations in Category 2 and Category 3, the FAA proposes
measurements of energy that would ensure a low likelihood that the
small unmanned aircraft would cause a casualty or fatality upon impact.
The FAA's use of 11 ft-lbs as the basis for the injury standard
applicable to Category 2 operations is consistent with existing
commercial space safety regulations at 14 CFR part 417, Launch Safety,
and longstanding Range Commander's Council (RCC) standards.
Specifically, 14 CFR 417.107(c) establishes 11 ft-lbs as the impact
kinetic energy threshold for inert debris from a commercial space
launch operation that could cause a casualty from blunt trauma to a
person not under a covered structure. The FAA bases this threshold on
extensive government research of human injury thresholds discussed in
the RCC Common Risk Criteria Standards for National Test Ranges, RCC
Standard 321 and associated supplements. The stated intent of RCC
Standard 321 is to ``establish safety criteria and guidelines to
provide definitive and quantifiable measures to protect mission-
essential personnel'' \65\ and the general public from launch and
reentry hazards generated by guided and unguided missiles, missile
intercepts, space launches and reentry vehicles. The RCC conducted
extensive testing and analysis to address blunt force injuries that may
result from falling inert debris. Based upon this information and human
injury criteria, the RCC established threshold values that correlate to
low probabilities of specific human injury levels. Section 6.2 of RCC
321-07, for example, states ``the threshold criterion for protection
against blunt trauma and crushing injuries is 11 ft-lbs impact kinetic
energy.'' \66\ Section 6.2.1 of RCC 321-10 states, this criterion is
designed to afford protection against injury levels of an Abbreviated
Injury Scale (AIS) of level 3 or worse. This statement explains that 11
ft-lbs is the appropriate standard for a ``low probability'' of an AIS
level 3 injury. In addition, the standard is consistent with the use of
11 ft-lbs as the threshold for casualties in commercial space launch
safety analyses and with the ARC recommendation. The document further
establishes 25 ft-lbs as a higher impact kinetic energy threshold for
limiting fatalities due to blunt trauma. When modeling debris fragments
and their impacts on unsheltered people, the RCC standard explains the
impacts that transfer kinetic energy in the amount of 25 ft-lbs or less
have a low probability of causing a fatality.
---------------------------------------------------------------------------

    \65\ RCC Range Safety Group, Common Risk Criteria Standards for
National Test Ranges: Supplement 321-10 at sec. 1.3 (2010).
    \66\ RCC Range Safety Group, Common Risk Criteria Standards for
National Test Ranges: Supplement 321-07 at sec. 6.2.a (2007).
---------------------------------------------------------------------------

    This research arose from criteria the RCC issued in 1999, which
provided government and military Range Commanders a common approach to
safety risk assessments.\67\ These documents refer to the impact
kinetic energy data in RCC Document 321-00 as the basis for calculating
the casualty expectation criteria for unmanned aircraft operations at
national test ranges. Using the probability of fatality data developed
in RCC 321-00, the RCC determined casualty expectation criteria with
the same data the FAA uses in this proposed rule to establish the
impact kinetic energy thresholds.
---------------------------------------------------------------------------

    \67\ RCC Range Safety Group, Range Safety Criteria for Unmanned
Vehicles: Standard 323-99 (1999); see also Range Safety Criteria for
Unmanned Vehicles--Rationale and Methodology Supplement (1999).
---------------------------------------------------------------------------

    Because the RCC impact kinetic energy thresholds are based on
impacts from metallic fragments, the criteria does not take into
account any potential loss of kinetic energy from non-rigid objects
that can be shown to transfer only a portion of their total kinetic
energy to person upon impact. The RCC thresholds presume all kinetic
energy from a rigid object would transfer to a person upon impact. The
ASSURE research, however, demonstrates that small UAS do not always
impact a person or surface in the same manner that metallic fragments
impact them.

The FAA proposal for using injury avoidance as a threshold, rather than
an impact kinetic energy threshold alone, takes into account the
disparity between impacts from metallic fragments and small unmanned
aircraft. The performance-based standards the FAA proposes in this rule
intend to encourage development of testing methodologies and other
means of compliance that account for the transfer of kinetic energy
that may occur upon impact from small unmanned aircraft.
    With regard to analyzing the transfer of energy, the FAA considers
impact kinetic energy thresholds established in the RCC standards as
instructive. The RCC based its thresholds primarily on the assumption
that inert debris exists in rigid form. Because kinetic energy depends
on weight and speed, the human injury models of the RCC report recorded
data of impacting fragments for various weights, such as one, 10, or 80
pounds. The resulting kinetic energy of these weights can be measured
due to the changing velocity of the impacting fragments. For example, a
lightweight unmanned aircraft flying at a certain speed could have the
exact same impact kinetic energy as a heavier unmanned aircraft flying
at a slower speed. Due to the variability in the kinematics of these
systems, the FAA considers the transfer of this impact energy to be the
determining factor for safe operations over people. For determining
whether a means of compliance fulfills the safety levels the FAA
proposes at Sec. Sec.  107.115(b)(1) and 107.120(b)(1), the FAA will
consider long-held science on which the RCC standards are based, as
well as other analytical models that may be relevant at the time of the
FAA's analysis.
    Based on the foregoing, the FAA identified two existing impact
kinetic energy thresholds that analyze public safety risk from
commercial space launches, government space launches, and aircraft
operations at national test ranges. The FAA concludes, based on the
research cited above, that a small unmanned aircraft that transfers no
more than 11 ft-lbs of kinetic energy to a person on impact would have
a low probability of causing a casualty to that person. Therefore, the
FAA considers this rule's proposed standard for Category 2 to consist
of the limitation of the results, or injury, that arise from a transfer
of 11 ft-lbs of kinetic energy from a rigid object upon impact.
Similarly, the FAA proposes setting the standard for Category 3 as
limiting the injury to that of an impact of 25 ft-lbs from a rigid
object because a small unmanned aircraft that transfers no more than 25
ft-lbs of kinetic energy to a person on impact would have a low
probability of causing a fatality to that person. As discussed further
below, the FAA also proposes standards for exposed rotating parts
applicable to Categories 2 and 3 as well as operational restrictions
for Category 3 operations.
(b) Measurements of Transfer of Energy
    With regard to energy transfer, the FAA proposes setting the safety
level in this rule as the limitation of injuries caused by the total
kinetic energy transferred from a rigid object to a person upon impact,
rather than the impact kinetic energy per unit area. The FAA
acknowledges the ARC recommended the FAA adopt a measurement of J/cm\2\
for the energy limitation aspect of this proposed rule, but declines to
propose this measurement. This decision is the result of the fact that
the contact area varies considerably, based on many factors (varying
shapes of aircraft, size and positioning of the person, and so on).
Further, the orientation of the aircraft at the time of impact will
also greatly affect the contact area as well as the position of the
person who is impacted. Impact kinetic energy thresholds alone consider
neither the dimensions of the small unmanned aircraft nor the area of
the small unmanned aircraft that makes contact with a person upon
impact. Moreover, impact kinetic energy transferred to a person may
result in blunt trauma injuries. Thresholds specified in units of
energy per area, such as J/cm\2\, are used to measure the risk of non-
lacerating, or ``chunky penetration'' injuries, not blunt trauma
injuries.\68\
---------------------------------------------------------------------------

    \68\ Impact kinetic energy per unit area, such as J/cm\2\ is the
most appropriate means of measuring non-lacerating or ``chunky
penetration'' injuries, not blunt trauma injuries. A4 Report at 83
(Table 30, comparison of energy densities and related metrics for
chunky penetration).
---------------------------------------------------------------------------

    Manufacturers or others who do not seek to use an industry
consensus standard may also present a manner of measuring energy
transfer the FAA deems acceptable, via a custom means of compliance.
Once the FAA accepts a means of compliance for measuring the transfer
of energy that accounts for mitigating factors, such as dissipation or
absorption of post-impact kinetic energy by the small unmanned
aircraft, the FAA would consider the means as fulfilling the
performance-based requirements of Category 2 and 3, respectively. As
described below, manufacturers would then take advantage of the
accepted means of compliance by declaring a particular make and model
of small UAS they have manufactured fulfills the appropriate standard
by submitting a declaration of compliance.
    At present, no means of measuring exists to establish that a
specific amount of energy equates with a likelihood of injury.
Nevertheless, the FAA's adoption of a performance-based standard as a
performance-based measurement should encourage development of various
means of compliance to ensure small UAS do not present an unacceptable
level of risk of injuring a person when operating over people. The FAA
emphasizes further research is necessary on the subject of proper
modeling of small unmanned aircraft impact physics as it correlates to
human injury. From the variation of kinetic energy thresholds in the
historical blunt trauma research, the FAA understands the rigidity of
the small unmanned aircraft can have an effect on the impact dynamics,
as seen when comparing small UAS data with rigid object data points.
Additional research may suggest other ways of measuring injury that
results from the transmission of energy upon impact.
    The FAA seeks comment on whether establishing an impact kinetic
energy threshold and using kinetic energy transferred upon impact is
the appropriate method to measure the potential injury a small unmanned
aircraft could cause upon impact with a person.
(c) Reduction in Likelihood of Injury
    As noted above, the FAA uses the term ``safety level'' to refer to
the limitation of injury severity caused by transfers of kinetic energy
from a rigid object, exposed rotating parts, or safety defects. The FAA
proposes to establish the safety levels set forth in Category 2 and 3
based on a risk assessment that does not attempt to predict the precise
types or probability of injuries. A chain of events must occur for a
small UAS to cause an injury. A Category 2 operation resulting in a low
probability of casualty and a Category 3 operation resulting in a low
probability of fatality assumes a small UAS would experience a failure
during an operation over people and that it would impact a person. A
one hundred percent chance that each of these events would occur is
impossible. Therefore, the probability of injury such thresholds would
present is uncertain.
    This proposal also does not consider which part or section of a
small unmanned aircraft impacts a person, but rather assumes the
occurrence of the worst case in a typical failure mode. For example,
the orientation of a small unmanned aircraft as it impacts a person
might affect the amount of kinetic energy it transfers. Similarly, if

the arm of a small unmanned aircraft is bendable or breakable and comes
into contact with a person, the full energy of the impact might not
transfer to the person; therefore, that person may experience an injury
of reduced severity. The FAA assumes that, to determine the maximum
kinetic energy the small unmanned aircraft transfers upon impact with a
person, the test would utilize the aircraft orientation likely to cause
the most harm to the person. For example, the standard assumes the
small unmanned aircraft would not impact the person at an angle or in a
manner that curtails the fall of the small unmanned aircraft. The
standard does not take into account these less hazardous orientations
because a small unmanned aircraft's position at the time of impact with
a person is unpredictable.
    In addition, the FAA is aware that different parts of the human
body have different vulnerabilities depending on the weight of the
impacting object. The 11 ft-lbs and 25 ft-lbs thresholds for Category 2
and 3 consider these variations using data, analyses, and studies
performed by the RCC. This threshold also considers these variations
for all parts of the body for both adults and children, including when
people are in various positions, such as standing, sitting, and prone.
    The FAA seeks comment on methods, processes, or procedures used in
the studies on which the FAA bases these proposed standards. In
particular, the FAA invites comment on the costs associated with
meeting these proposed standards, in light of such research. Collecting
operational safety data for small UAS operations over people will
assist in the FAA's evaluation of the effectiveness and continued
applicability of the safety standards the agency proposes. The FAA also
seeks comment on the need for a process, and the details of that
process, to enable the FAA to reassess and possibly adjust the safety
thresholds in this proposed rule based on such safety data. The FAA
acknowledges the lack of certainty concerning failure rates and
estimates of injury severity based on failures. The FAA seeks specific
information regarding methods used to deal with such uncertainty.
(2) Exposed Rotating Parts
    Exposed rotating parts, which could cause lacerations or other
serious injuries if these parts were to come into contact with a
person, are a feature common to small UAS on the market today. Due to
the hazards this feature can pose, the FAA has determined small UAS
eligible for operations in Category 2 and 3 of this proposed rule must
be designed such that they would not lacerate human skin upon impact
with a person.
    The ARC recommended manufacturers limit the risk of injuries caused
by exposed rotating parts because energy transfer requirements alone
would not mitigate this risk sufficiently. The ARC stated the analysis
of exposed rotating parts should ``focus on serious injury (level 3 or
greater)'' without any distinction based on the category of operation.
Although the ARC used the term ``exposed rotating parts'' to identify
any rotating part that could cause an injury, the most common example
of this on a small unmanned aircraft is a propeller. In a multi-rotor
unmanned aircraft configuration, propellers are generally arranged
symmetrically around the periphery of the unmanned aircraft. In a
fixed-wing unmanned aircraft configuration, propellers are generally
arranged in either a puller (propeller in front) or pusher (propeller
in back) configuration. These propellers generally spin at high speeds,
and could cause injuries, even if on small unmanned aircraft.
    The ASSURE study predicted that the severity of cutting or tearing
injuries could be greater than impact injuries from existing rotorcraft
designs on UAS.\69\ The study indicated blade tip speed, blade
sharpness, and leading edge sharpness may all significantly affect the
potential for laceration of human skin from UAS blades. The ASSURE
study clarified that all propellers can lacerate skin. Based on this
research, the FAA concludes any small UAS that conducts operations over
people should not have exposed rotating parts capable of lacerating
human skin upon impact with a person. Manufacturers would need to
ensure the small UAS fulfills this standard using a means of compliance
the FAA accepts. This requirement would not apply to operations of
small UAS that occur pursuant to Category 1. The FAA invites public
comment, however, on the issue of whether operations of small UAS
eligible to operate pursuant to Category 1 should be subjected to a
performance-based requirement for exposed rotating parts.
---------------------------------------------------------------------------

    \69\ A4 Report at 89.
---------------------------------------------------------------------------

    The FAA is aware that exposed rotating parts could be capable of
injuries beyond just lacerations. For example, injuries to hair, teeth
or eyes, rather than skin, may occur. The FAA, however, considered
carefully the proposed limitation on exposed rotating parts that could
lacerate human skin and determined the prohibition on skin lacerations,
combined with the limitation on transfer of kinetic energy on impact
and prohibition of safety defects, will mitigate the risk of injuries
that may not involve skin. Moreover, the FAA is keenly aware that
permanently disfiguring injuries could result from lacerations of
skin.\70\ As a result, and based on the ASSURE research that
highlighted the concern that exposed rotating parts present, the FAA
proposes a general prohibition on such parts that could lacerate skin.
---------------------------------------------------------------------------

    \70\ In this regard, the FAA's decision to ensure protection of
skin from lacerating injuries is similar to the logic the National
Highway Traffic Safety Administration employs. See Federal Motor
Vehicle Safety Standards: Glazing Materials, 65 FR 44710, 44711
(July 19, 2000) (explaining NHTSA's decision to assess whether
``advanced glazings'' are more likely to cause lacerations than
``current glass,'' and stating, ``[a]lthough facial lacerations
injuries are relatively minor (AIS 1 or 2), they . . . can be
disfiguring'').
---------------------------------------------------------------------------

    This proposal is the result of the agency's determination that any
allowance for serious injury from exposed rotating parts would have a
compounding effect and would add to the overall level of risk for
Category 2 and 3 operations. The FAA concluded that this proposed
standard of prohibiting lacerations of human skin would maintain the
risk posed by Category 2 operations as a low probability of causing a
casualty, and Category 3 operations as a low probability of causing a
fatality. As described below, manufacturers would fulfill this standard
by either providing descriptions of their test methodology and test
data; analyses with substantiating data; or inspection information.
    A manufacturer may establish it has fulfilled the limitation on
exposed rotating parts by ensuring the small unmanned aircraft simply
does not have parts that are exposed. For example, if the propellers
that provide lift and thrust for the small unmanned aircraft are
internal to the unmanned aircraft, such as in a ducted fan
configuration, and are incapable of making contact with a person as a
result of an impact, then the parts would not be exposed, and the
aircraft would satisfy this proposed requirement. The FAA may require
testing and analysis to conclude the rotating parts could not become
exposed as a result of an impact with a person. For example, if the
forces on the small unmanned aircraft during an impact with a person
could cause structural failures that result in the rotating parts
becoming exposed, then that design would not achieve the requisite
safety level of this proposed rule. The FAA seeks comment on other

means of compliance it could include in a final rule.
5. Means of Compliance
    This rule proposes several performance-based requirements that
would accommodate varying means of compliance. In this manner, the FAA
would build flexibility into the regulations, which would allow the
regulatory scheme to progress alongside the fast pace of small UAS
innovation and development. Additionally, this rule would establish a
process by which the FAA could expedite the acceptance of voluntary
consensus standards as means of compliance with requirements related to
impact kinetic energy and exposed rotating parts. This proposal would
align with the direction of the Office of Management and Budget (OMB)
Circular A-119, which favors the use of performance-based regulations
and voluntary consensus standards. The FAA proposes to accept both
voluntary consensus standards and non-consensus standards as means of
compliance with the proposed performance-based requirements.
    Given the current absence of voluntary consensus standards that
could apply to operating small unmanned aircraft over people, the FAA
is proposing one means of compliance for each proposed performance-
based standard for operations over people, to allow interested
stakeholders to begin demonstrating compliance as soon as this rule
goes into effect. Additionally, the FAA is proposing a process by which
it would approve additional means of compliance. A voluntary consensus
standards body, an industry, a manufacturer, or an individual may
develop these means of compliance. Each means of compliance, including
the FAA's proposed means, would constitute one way, but not the only
way, to satisfy the proposed performance-based standards. The FAA would
consider other means of compliance as entities or individuals develop
and submit them to the FAA for review.
(a) Establishing Compliance
    The FAA proposes to require a manufacturer producing a small UAS
eligible for Category 2 or 3 operations to establish compliance with
the proposed safety level by using a means of compliance the FAA has
accepted. A manufacturer would then declare on its Declaration of
Compliance what means of compliance, or combination of them, it used.
This proposal sets forth three ways of establishing compliance: (1) The
FAA-proposed means of compliance, discussed in this preamble; (2) an
FAA-accepted means of compliance developed by a voluntary consensus
standards body; and (3) an FAA-accepted custom means of compliance
developed independent of either the FAA or a voluntary consensus
standards body. A custom means of compliance would require more
extensive review by the FAA than a means of compliance developed by a
voluntary consensus standards body.
(1) FAA-Provided Means of Compliance
    Under this proposed rule, any person may establish compliance with
the applicable safety levels the FAA proposes in this rule in a variety
of ways. The FAA must affirmatively accept the means of compliance
before a manufacturer can rely upon it to demonstrate compliance.
Because no means of compliance currently exist to address the
requirements this rule proposes, the FAA proposes one means of
compliance it would accept immediately, to allow manufacturers to
demonstrate their small UAS would fulfill the level of safety the FAA
proposes in this rule for operations over people. Section IV.B.5.c)
provides a description of this means of compliance. The FAA may provide
additional FAA-accepted means of compliance based on future research.
(2) Voluntary Consensus Standards Body Means of Compliance
    A voluntary consensus standards body develops standards that
incorporate openness, balance, due process, appeals process and
consensus. These characteristics also necessarily result in voluntary
consensus standards being peer reviewed. Because voluntary consensus
standards bodies are composed of a wide selection of industry
participants, and often include FAA participation, the FAA expects its
review of a means of compliance developed by a voluntary consensus
standards body to be more expeditious than a custom means of compliance
developed in the absence of a voluntary consensus standards body.
    The FAA has an extensive history of working with voluntary
consensus standards bodies such as RTCA, ASTM International, Society of
Automotive Engineers (SAE), and Institute of Electrical and Electronics
Engineers (IEEE). In accordance with the ARC recommendation to use
industry consensus standards for small UAS, and with the precedent
already set for general aviation aircraft, the FAA anticipates
voluntary consensus standards bodies to take the lead in offering means
of compliance for FAA review.
(3) Custom Means of Compliance
    The FAA proposes that a manufacturer or other person may propose a
custom means of compliance to fulfill the safety level set forth in
this proposed rule's impact kinetic energy or exposed rotating parts
standards. As discussed further in this section, a custom means of
compliance would be subject to a more comprehensive review than a means
of compliance submitted by a voluntary consensus standards body. If a
person proposes an alternate means of compliance to the impact kinetic
energy or exposed rotating parts requirements in the rule, or an
alternate method to any FAA-accepted means of compliance, the FAA would
evaluate the means of compliance on a case-by-case basis. A custom
means of compliance would need to set forth a manner by which an
applicant could comply with the impact kinetic energy and exposed
rotating parts standards of Sec.  107.115(b)(1) or Sec.  107.120(b)(1),
as applicable.
    Applicants should consider carefully the additional time and effort
that could be necessary to coordinate a new or alternate means of
compliance when scheduling their projects. FAA coordination may require
the efforts of FAA technical specialists, Chief Scientific Technical
Advisors, and other government agencies. The use of existing FAA-
accepted means of compliance would be more expeditious because the FAA
has already reviewed them. Not all developers of custom means of
compliance would be manufacturers who submit a Declaration of
Compliance. The FAA, therefore, would provide a process by which an
applicant could submit a custom means of compliance for FAA review
separate from submitting a Declaration of Compliance. This process is
described in further detail in Advisory Circular 107-2.
    When reviewing a custom means of compliance, the FAA would utilize
a comprehensive set of criteria. To demonstrate compliance with the
impact kinetic energy or exposed rotating parts requirements, the FAA
would determine whether the applicant has shown compliance by testing,
analysis, or inspection that demonstrates the manufacturer has met the
appropriate level of safety provided in the proposed standards. The FAA
would also determine whether the custom tests or analyses are performed
in accordance with accepted methods used by the medical industry,
consumer safety groups, or other peer-reviewed test methods. In
addition, the FAA would determine whether the proposed

means of compliance required unreasonable skill on behalf of the remote
pilot in command or incorporation of mitigations to meet the standards.
Lastly, the FAA would determine whether the means of compliance
addressed design features such as deployable devices, parachutes, or
other features. Those additional features would require the FAA's
review to determine whether they assist in achieving an acceptable
means of compliance when those features function as intended.
    The FAA's proposed regulatory text in Sec.  107.125 of this rule
sets forth the information the FAA must receive in determining whether
to accept the means of compliance. This information would ensure FAA
oversight at a level that is appropriate for the risk operations of
small UAS over people present. In addition, the model for ensuring
compliance that the FAA proposes in this rule would also permit the
FAA's adoption of an industry consensus standard that fulfills the
applicable standard.
(b) Submittal and FAA Acceptance of Means of Compliance
    As described previously, manufacturers or industry stakeholders may
establish compliance in a variety of different ways; however, the FAA
must affirmatively accept the means of compliance before the
manufacturer can rely on it for self-certification.
    Any person may submit a means of compliance to the FAA for review.
To submit a means of compliance, a person would be required to identify
whether the manufacturer achieves compliance by way of test, analysis
or inspection, and provide a detailed description of the means of
compliance that establishes exactly how the testing, analysis, or
inspection fulfills the safety level set forth in the standards of
Sec.  107.115(b)(1) or Sec.  107.120(b)(1). The rule proposes requiring
any person who submits such a custom means of compliance to provide any
substantiating data, studies, information, or the like to explain
precisely how their proposed means of compliance achieves the safety
level that the standards of Sec.  107.115(b)(1) or Sec.  107.120(b)(1)
represent. For example, if a manufacturer would achieve compliance by
conducting testing, then the manufacturer's request for the FAA's
acceptance of the means of compliance should include test procedures
that outline the test methodology, an analysis to support the
equivalency of the testing to the safety level identified in Sec.
107.115(b)(1) or Sec.  107.120(b)(1), and all substantiating data that
supports the test, methods, results, and conclusions. On the other
hand, if a manufacturer seeks to achieve compliance by analysis, then
the manufacturer should submit the standard to which the manufacturer
compared his or her specific model of small unmanned aircraft and
explain how the data and interpretation of it establishes that the
manufacturer fulfills the applicable standard. For example, if the
manufacturer has a simulation with modeling of the impact dynamics that
the FAA has validated, then the FAA would evaluate the analysis that
utilizes the impact dynamics data to confirm that the analysis
establishes fulfillment of the standard. In sum, anyone may submit a
variety of types of means of compliance using testing, analyses,
inspections, or any combination of them, in seeking the FAA's
acceptance of their means of compliance. As described previously, the
FAA would more closely scrutinize custom means of compliance not
submitted by a voluntary consensus standards body.
    The FAA would indicate acceptance of a means of compliance by
publishing a Notice of Availability in the Federal Register identifying
the means of compliance as accepted and by sending a letter to the
applicant accepting the proposed means of compliance. If a manufacturer
referred to a custom means of compliance on its Declaration of
Compliance, FAA acceptance of that Declaration of Compliance would also
indicate acceptance of the custom means of compliance.
    Once the FAA has accepted a custom means of compliance, the FAA
would consider it as equally valid as a voluntary consensus standard
that the FAA had accepted. If the FAA did not accept a custom means of
compliance, the FAA would notify the applicant of the rationale for its
decision and would reject any associated Declarations of Compliance
that rely on that particular custom means of compliance. For both
custom means of compliance and voluntary consensus standards, the FAA
could rescind a previously accepted means of compliance if the FAA
determined from service history that the means of compliance did not
meet the applicable standards for operations over people.
(c) Types of Means of Compliance
    This proposal provides latitude for people who request acceptance
of a means of compliance to show compliance by testing, analyses,
inspections, or any combination of the three. In all proposed means of
compliance cases, the FAA would review data based on the worst-case
scenario of a typical failure of the small unmanned aircraft. The
applications for approval of proposed means of compliance that include
data and relevant information regarding a reasonably foreseeable worst-
case scenario will facilitate the most straightforward, efficient type
of review from the FAA. In general, the FAA expects the amount of
information needed to justify the proposed means of compliance will be
proportionate to the complexity of factors relevant to both common and
worst-case scenarios.
(1) Tests
    Anyone may submit test data to show their small UAS fulfills the
safety level the FAA proposes in this rule. The description below
describes tests used for both a pre-accepted means of compliance based
solely on the impact kinetic energy measurement, as well as tests used
for an alternate means of compliance.
(a) Impact Kinetic Energy Transfer
    As explained below, this proposed rule includes one potential means
of compliance that manufacturers may use to declare compliance. For all
potential means of compliance, the FAA expects manufacturers, during
their testing, to install or enable any mechanisms that could affect
the transfer of kinetic energy upon impact. For example, manufacturers
must employ any systems that could limit the velocity of the small
unmanned aircraft upon which the means of compliance relies. In such
cases, the manufacturer should provide information on the proper use of
those systems or equipment, as well as any restrictions, in the remote
pilot operating instructions, as discussed in section IV.B.9.
    The FAA anticipates a person who seeks to comply via a custom means
of compliance would implement these types of systems or equipment
through hardware, software, or a combination of both. If an operator
can operate the small UAS regardless of whether these systems or
equipment are enabled or installed, such as in a variable-mode small
UAS, then the manufacturer should provide information in the remote
pilot operating instructions to ensure remote pilots in command
understand any restrictions or limitations associated with the
different modes.
Pre-Accepted Means of Compliance
    One means, but not the only means, of complying with the proposed
limitation with regard to the transfer of kinetic energy upon impact
would entail a manufacturer's calculation of kinetic energy transferred
when a small

unmanned aircraft impacts a person. This type of means of compliance
would not account for impact dynamics or other factors, but consists of
using only the formula the FAA describes to measure kinetic energy upon
impact. Use of this formula alone would establish the small unmanned
aircraft fulfills one of the standards described above because 11 ft-
lbs (for Category 2 operations) and 25 ft-lbs (for Category 3
operations) are thresholds that establish low probability of occurrence
of a casualty or fatality would exist, respectively.
    This pre-accepted means of compliance would be based on the maximum
performance capabilities of a small unmanned aircraft during a typical
failure mode. To test a small unmanned aircraft using this means of
compliance, a manufacturer would first determine the maximum forward
airspeed that the small unmanned aircraft may attain at full power in
level flight during typical environmental conditions. The manufacturer
would use a reliable and accurate airspeed measurement method. For
example, a manufacturer could measure the maximum speed using a GPS
groundspeed indicator, a radar gun, or tape measure and stop watch.
Next, the manufacturer would determine the ground impact speed
resulting from an unpowered free-fall from the highest altitude the
small UAS is capable of attaining at full power. The ground impact
speed could be determined by performing a drop test from the altitude
determined in the previous step using a reliable and accurate vertical
speed measurement method under typical environmental conditions.\71\
---------------------------------------------------------------------------

    \71\ Small unmanned aircraft operated under part 107 may not
exceed the speed limitations in part 107 unless authorized under a
Certificate of Waiver or an exemption. See 14 CFR 107.51(a) (stating
the ground speed of the small unmanned aircraft may not exceed 87
knots (100 miles per hour)) and Sec.  107.205 (listing Sec.
107.51(a) as a provision that is subject to waiver).
---------------------------------------------------------------------------

    If a manufacturer determines it is unreasonable to perform a drop
test from the highest attainable altitude, then the manufacturer may
perform a drop test from a lower altitude sufficient to determine the
small unmanned aircraft free-fall aerodynamic characteristics, such as
the coefficient of drag, to calculate accurately the ground impact
speed from a free-fall from the highest attainable altitude. The
substantiating data the manufacturer would submit would include
sufficient information concerning the environmental conditions and the
maximum speeds the manufacturer utilized, as well as any unique test
conditions for both the level flight and free-fall scenarios.
    The above tests account for speeds a small unmanned aircraft could
reach prior to or during a typical failure mode, such as losing power
and falling with both a vertical and horizontal speed component. The
tests do not take into account small UAS failure modes or pilot actions
that would cause the small unmanned aircraft to exceed the speeds
determined in the previous steps. One example is a powered descent in
which the ground impact speed of the small unmanned aircraft exceeds
its unpowered free-fall ground impact speed. The FAA assumes these
types of failure modes or pilot actions are not typical, and while
possible, have a low likelihood of occurring. If a manufacturer
determines these types of failure modes or pilot actions could
typically occur and result in speeds greater than those determined in
the previous steps, then the manufacturer should use higher speeds to
determine the maximum impact kinetic energy.
    Once the manufacturer determines the maximum speeds associated with
a horizontal and vertical impact, the manufacturer would ascertain the
highest combination of these speeds that he or she could achieve as a
result of a reasonably foreseeable failure. These conclusions would
lead to the manufacturer's determination of the maximum impact kinetic
energy. In such a case, the manufacturer should use the highest
combination of horizontal and vertical impact speeds unless he or she
can show the highest combination is not possible in a reasonably
foreseeable failure and another combination is therefore more
appropriate. The manufacturer should assess reasonably foreseeable
failures caused by system or equipment loss of function or malfunction
as well as those that pilot error could cause.
    To calculate the impact kinetic energy, manufacturers would use the
following equation:

    KEimpact = 0.0155 * w * v\2\

Where KEimpact is the maximum impact kinetic energy in ft-
lbs, w is the weight of the small unmanned aircraft measured in pounds,
and v is the maximum impact speed measured in feet per second (ft/
s).\72\
---------------------------------------------------------------------------

    \72\ The FAA used the constant 0.0155 in order to allow a person
to plug in the weight, rather than the mass, of a small unmanned
aircraft. Using the following equations, KE = \1/2\
*mass*velocity\2\ and mass= weight/gravity, the FAA determined that,
in English units, KE = \1/2\ * weight/32.17 * velocity\2\ and KE =
\1/2\ * (1/32.17) *weight* velocity\2\ therefore KE = 0.0155 *
weight * velocity\2\. Note that 32.17 is the gravitational constant
measured in English units.
---------------------------------------------------------------------------

    For example, a small UAS that weighs 1.0 pound and has a maximum
impact speed of 26 ft/s has a maximum impact kinetic energy of:

KEimpact = 0.0155 * 1.0 * (26) \2\ = 10.5 ft-lbs

    Similarly, a small UAS that weighs 1.0 pound and has a maximum
impact speed of 40 ft/s has an impact kinetic energy of:

KEimpact = 0.0155 * 1.0 * (40) \2\ = 24.8 ft-lbs

    Utilizing the formula KEimpact = 0.0155 * w * v \2\, the
two tables below provide examples of maximum impact speeds, rounded to
whole numbers, associated with the impact kinetic energy thresholds of
the different categories and the weight of the small unmanned aircraft.
One table provides speeds in feet per second and the other table
provides speeds in miles per hour. Manufacturers could use these tables
when following this proposed means of compliance based on the maximum
performance of a small UAS. These tables do not consider any energy-
absorbing characteristics of a small unmanned aircraft that may reduce
the amount of energy transferred to a person during an impact.
---------------------------------------------------------------------------

    \73\ The values provided in Tables 4 and 5 are based on the
factors summarized in footnote 75.

  Table 4--Maximum Impact Speeds (ft/sec) for a Given Weight and Impact
                           Kinetic Energy \73\
------------------------------------------------------------------------
                                                 Maximum speed (ft/sec)
                                               -------------------------
                 Weight (lbs)                    Category 2   Category 3
                                                (11 ft-lbs)  (25 ft-lbs)
------------------------------------------------------------------------
1.0...........................................           26           40
1.5...........................................           22           33
2.0...........................................           19           28
2.5...........................................           17           25
3.0...........................................           15           23
------------------------------------------------------------------------

   Table 5--Maximum Impact Speeds (mph) for a Given Weight and Impact
                             Kinetic Energy
------------------------------------------------------------------------
                                                   Maximum speed (mph)
                                               -------------------------
                 Weight (lbs)                    Category 2   Category 3
                                                (11 ft-lbs)  (25 ft-lbs)
------------------------------------------------------------------------
1.0...........................................           18           27
1.5...........................................           15           22
2.0...........................................           13           19
2.5...........................................           11           17
3.0...........................................           10           16
------------------------------------------------------------------------

    This proposed means of compliance does not account for the use or
testing of design features such as parachutes, ballistic recovery
systems, or other deployable devices that, once deployed,

create drag to reduce the maximum impact speed. The discussion below,
concerning custom means of compliance, addresses the potential use of
such design features.
    As discussed in section IV.B.7.b), if a remote pilot in command or
other person modified a small unmanned aircraft in a manner that
increases its maximum speed or weight beyond what is identified in the
remote pilot operating instructions, then the small unmanned aircraft
would no longer fulfill the safety level set forth at Sec.
107.115(b)(1)(i) or Sec.  107.120(b)(1)(i). To conduct operations over
people, a manufacturer would have to verify that the modifications
satisfied the impact kinetic energy requirements by re-testing and
submitting a new Declaration of Compliance for the modified small UAS.
Custom Means of Compliance
    Under this proposal, any person may propose a custom means of
compliance showing the small unmanned aircraft achieves the safety
level the FAA proposes in Sec.  107.115(b)(1) or Sec.  107.120(b)(1).
At the time of this proposal, the FAA has not identified a means
available to determine the actual amount of kinetic energy that is
transferred upon impact with a person. Nevertheless, research into this
area is ongoing. Taking advantage of the opportunity to employ a
customized solution that ensures compliance with the safety levels set
forth in Sec. Sec.  107.115(b)(1) and 107.120(b)(1), the manufacturer
would request the FAA's acceptance of a means of compliance that
establishes how the manufacturer has made this determination.
    The structural configuration, materials of construction, or other
design features may function to reduce the amount of the total kinetic
energy that is transferred to a person from a small unmanned aircraft
during an impact. The FAA's proposed means of compliance described
above does not take into account the effect of these aspects during an
impact with a person, because it assumes that the total kinetic energy
of the small unmanned aircraft would be transferred to the person upon
impact. In reality, however, the small unmanned aircraft may transfer
much less energy. For example, the presence of energy-absorbing
materials, or an energy-absorbing protective cage, may reduce the
transfer of kinetic energy during an impact with a person. Under these
circumstances, a manufacturer may wish to provide data showing the
amount of kinetic energy that is transferred to a person during an
impact, based on the impact-absorbing characteristics of the small
unmanned aircraft. In this regard, some small UAS manufacturers may
seek to use design features such as parachutes or other deployable
devices to establish that a reduced amount of transferred energy exists
for their small unmanned aircraft. Such design features would require
the FAA's review to determine whether they assist in achieving an
acceptable means of compliance if the small UAS is reliant on the
proper functioning of these features.
    The means of compliance discussed in the preceding paragraphs
should not be confused with the Declaration of Compliance discussed in
Section IV.B.7.b), below. The testing or analysis conducted to
determine the maximum kinetic energy that a small unmanned aircraft
could transfer to a person upon impact during a typical failure
scenario would be the actual means of compliance under this rule. The
Declaration of Compliance would be the ``evidence'' or ``artifact''
that is the final step in demonstrating to the FAA that the small UAS
is in compliance with this proposed rule.
(b) Exposed Rotating Parts
    Anyone who seeks approval of a means of compliance may establish,
using test descriptions, results, and data, that a small unmanned
aircraft does not contain any rotating parts that could cause
lacerations of human skin. An industry consensus organization could
develop a standard for small unmanned aircraft that have rotating parts
that are protected by safety features, such as propeller guards. The
standard could require testing to support the determination that the
protective safety features accomplish their intended function of
preventing rotating parts from contacting a person during an impact. If
the manufacturer has tested those safety features and established they
would remain intact during an impact, this could be one means of
demonstrating that exposed rotating parts would not be capable of
lacerating human skin. If a small unmanned aircraft has rotating parts
that are exposed without any protective safety features, this rule
proposes to permit manufacturers or others to show through testing,
analysis or inspection that the rotating parts are not capable of
lacerating human skin upon impact with a person. Manufacturers or
others who seek to obtain approval of a means of compliance could
submit testing results and data that consider the size, shape,
rotational speed, material, and orientation of the rotating parts, and
concludes that these parts could not cause lacerations under any impact
scenarios.
    The more sophisticated or complex the materials or design of the
small unmanned aircraft, the more sophisticated the analysis or testing
should be. If a small unmanned aircraft had propellers made out of
soft, flexible material, a manufacturer would likely not need to employ
a means of compliance that had used a sophisticated analysis or testing
to demonstrate that the exposed rotating parts are not capable of
causing a laceration. However, if a manufacturer chooses to design a
small unmanned aircraft with exposed propellers that have sharp leading
edges, are made of a rigid material such as a carbon fiber composite
and are driven by high torque motors, that manufacturer would likely
have to perform a more sophisticated analysis or testing to demonstrate
that the propellers are not capable of lacerating human skin upon
impact with a person.
    Tests and associated data could also consist of utilizing exposed
rotating propellers at maximum revolutions per minute (RPM) and
contacting a medium that accurately represents human skin to establish
the propeller would not lacerate human skin. Similarly, for shrouded
propellers, such a test would establish that the propellers, while
turning, would not lacerate human skin. This test would establish the
effectiveness of the shroud or covering in a dynamic impact scenario.
Such a test may consist of a drop test or test using a pendulum to show
the shrouds remain effective when the propeller did not lacerate the
medium that represents human skin.
    Further, in the exemplar test described above, the test data
manufacturers or others submit would likely require a description of
the skin media used to determine that the shrouded propellers did not
lacerate human skin. Research that has led to the development of
standards and analyses on the subject of laceration injuries includes
the use of media such as a medium that is 10 percent gelatin,\74\ a

pig cadaver,\75\ plasticine,\76\ and a medium that may include chamois,
among other components.\77\ In this rulemaking, the FAA does not
endorse any of the aforementioned media as substitutions for human
skin. Rather, a manufacturer or industry consensus group that seeks
acceptance from the FAA of a means of compliance for establishing
exposed rotating parts would not lacerate human skin may provide test
data, analyses, or information that employs one of the above media, or
another medium. The FAA would review the entire submission of
information in order to determine whether the agency will accept the
potential means of compliance.
---------------------------------------------------------------------------

    \74\ Nicholas and Welsch, Ballistic Gelatin 2, Pennsylvania
State University Applied Research Laboratory, (2004), available at
http://www.firearmsid.com/Gelatin/Ballistic%20Gelatin%20Report.pdf.
    \75\ Sullivan et al, The Pig as a Model for Human Wound Healing,
The International Journal of Tissue Repair and Regeneration (2001);
Simon and Maibach, The Pig as an Experimental Animal Model of
Percutaneous Permeation in Man: Qualitative and Quantitative
Observations An Overview, Skin Pharmacology and Physiology 13.5 at
229-34 (2000).
    \76\ R[ouml]hrich et al, Skin Injury Model Classification Based
on Shape Vector Analysis, BMC Medical Imaging (2012), available at
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3599354/.
    \77\ Bir, et al., Skin Penetration Surrogate for the Evaluation
of Less Lethal Kinetic Energy Munitions, 220 Forensic Science
International 126, 127 (2012), available at http://www.sciencedirect.com/science/article/pii/S0379073812000801?via%3Dihub.
---------------------------------------------------------------------------

(2) Analysis
    A person may submit means of compliance that consist of analyses to
establish they have achieved the level of safety set forth in Sec.
107.115(b)(1) or Sec.  107.120(b)(1). In general, the FAA envisions
many proposed means of compliance could employ computer modeling
analysis to comply with the energy transfer standard or the exposed
rotating parts standard.
(a) Impact Kinetic Energy Transfer
    A proposed means of compliance may involve the use of analyses to
predict the amount of kinetic energy transferred upon impact with a
person. For example, a person who submits a means of compliance for
acceptance may seek to incorporate the aerodynamic effects (including
drag) of the small unmanned aircraft in a dynamic model of impact with
a person. The person could utilize computational fluid dynamics (CFD)
and finite element modeling (FEM) into the simulation. Such a
simulation would analyze the aerodynamic properties of the
aircraft.\78\ The model would calculate the interaction of the geometry
of the object in a flow field of the medium. Further, the model may
also simulate the dynamic interaction of the aircraft structure with a
validated model of a person to calculate the amount of kinetic energy
that is transferred.
---------------------------------------------------------------------------

    \78\ CFD, as used in the example above, refers to a simulation
that incorporates Navier-Stokes equations in a mathematical and
computational program that utilizes a multi-dimensional model of an
object. Constantin and Fioas. Navier-Stokes Equations. Univ. of
Chicago (1988).
---------------------------------------------------------------------------

    The person who seeks FAA acceptance of the means of compliance
would need to document the justification by including any analysis or
validation testing. Such records should establish validity of the
aerodynamic modeling as well as any other modeling techniques used in
the computation of impact kinetic energy values. Therefore, in
evaluating the proposed means of compliance based on analysis, the FAA
would expect submission of a full description of the process and an
explanation of the precise effect of the aerodynamic or other
characteristics that influence the flight envelope in which the small
unmanned aircraft operates. As with all proposed custom means of
compliance, the FAA would expect to evaluate information and data
concerning the worst-case scenario of a typical failure, combined with
mean data that depicts common scenarios within the aircraft's flight
envelope.
(b) Exposed Rotating Parts
    A person may also choose to confirm that exposed rotating parts on
the small unmanned aircraft they have manufactured would not lacerate
human skin by submitting analysis. Such analysis could include verified
data from relatable studies that models the small unmanned aircraft's
propellers at a maximum RPM, and the material choice of the propeller
and strength characteristics of an average human's skin in an FEM
simulation,\79\ and performs a finite element analysis (FEA) \80\ to
determine the laceration characteristics of the propeller. In such a
case, the FAA would expect the justification related to this method to
explain the rationale for concluding that the use of the previously
accepted data and FEA methodology is appropriate for the small UAS
design at issue.
---------------------------------------------------------------------------

    \79\ FEM, as used in the example above, refers to the
utilization of multi-dimensional model of an object that subdivides
the model into smaller components with attached algebraic equations
to help represent complex geometry and the dynamics associated to
such geometry during simulated stresses or impacts.
    \80\ FEA, as used in this example, is a numerical analysis of a
system to simulate the impact dynamic reaction when developed with
the material and design characteristics of the small unmanned
aircraft and surrounding objects that are relevant to the analysis.
Manufacturers may use FEA in computer modeling by using boundary
value problems for partial differential equations and variation
methods from calculus disparities to approximate a solution using
algebraic equations attached to small, subdivided pieces of the
model and by minimizing an associated error function.
---------------------------------------------------------------------------

(3) Inspection
    Manufacturers may also opt to confirm that the small UAS they have
manufactured would fulfill the safety level set forth in this proposed
rule by submitting information based on inspection. The FAA would
expect a full description of the inspection and the results or
conclusions from that inspection in order to accept the means of
compliance. Often, manufacturers may use the inspection option when a
small UAS has undergone modifications.
(a) Impact Kinetic Energy Transfer
    For purposes of establishing that the kinetic energy a small
unmanned aircraft transfers upon impact does not exceed the applicable
standard, a manufacturer may submit records to establish the
manufacturer has performed an inspection verifying that the small UAS
adheres to the standard. For example, a small UAS model the FAA has
previously determined fulfills the standard may continue to do so after
a modification when the manufacturer has simply replaced a part on the
small unmanned aircraft that weighs less than the original part. The
manufacturer would provide justification to verify the new part does
not alter the small unmanned aircraft such that it would increase the
kinetic energy the small unmanned aircraft transfers upon impact. In
this example, the manufacturer would present information to establish
that the overall weight and structure of the small unmanned aircraft
did not change to render it out of compliance with the applicable
standard regarding energy transfer.
(b) Exposed Rotating Parts
    In addition, a manufacturer's design with propeller blade guards to
fulfill the prohibition on exposed rotating parts may lend itself to a
verification of the means of compliance by way of inspection. For
example, a manufacturer with a previously accepted means of compliance
who wishes to replace or upgrade propellers could do so with a
propeller design of the same size, fit and weight that has fulfilled
the previously accepted means of compliance, and thus demonstrate
compliance through inspection means and not need to retest or perform
another analysis. When the manufacturer has completed previous tests
the FAA had verified demonstrated the effectiveness of blade guards,
the Administrator may presume

replacement of propellers would not have an effect on the function of
the guard to prevent laceration.
6. Aircraft with Variable Modes and Configurations
    Although this rule proposes three distinct categories of operations
over people, the FAA proposes to allow small UAS to be configured to
conduct operations within more than one category. For example, an
aircraft may be designed in such a way that it would be qualified to
conduct Category 2 operations in one mode or configuration, and
Category 3 operations in another mode or configuration. Alternatively,
a small UAS could meet the requirements to operate over people in one
mode or configuration, but not in another. For example, an aircraft
could operate within the restrictions of an operation over people, but
could also operate using higher performance characteristics when not
operating over people.
    To transition between various modes or configurations, a
manufacturer may choose to use a variety of methods, such as software-
enabled performance limitations including altitude or groundspeed
limitations, hardware configurations, or any combination thereof. Using
different modes or configurations, a manufacturer could design a small
UAS to meet the performance capabilities of multiple categories of
operations over people. Additionally, a manufacturer could design a
small UAS that has removable propeller guards or cages that would need
to be installed for operations over people but could be removed when
not operating over people.
    The design of a small UAS should not permit a remote pilot to
change the mode or configuration inadvertently. Regardless of whether
the method of transitioning between various modes or configurations
involves software or control station selections, a change of mode or
configuration must result only from a deliberate action on the part of
the remote pilot in command. For example, a remote pilot in command
could be required to enter a passcode that would intentionally alter
the mode of operation, thereby switching the category of operation for
the aircraft.
    To test a small UAS with multiple modes or configurations, a
manufacturer should test the small UAS in the mode or configuration
that allows the small UAS to meet the requirements for the category to
which a manufacturer wishes to declare compliance. If a small UAS could
meet the requirements for operations in both Category 2 and Category 3
based on the mode or configuration in which the small UAS is operated,
then the manufacturer must submit to the FAA a Declaration of
Compliance that includes each category for which the manufacturer has
tested or analyzed the small UAS.
    The FAA seeks comment on the need for means of compliance that
address incorporation of software, including software updates or
changes, to enable performance limitations, variable modes, or variable
configurations to meet the safety level proposed in this rule. The FAA
also seeks comment on how the FAA should review an acceptable means of
compliance for the impact kinetic energy or exposed rotating parts
safety thresholds to address the appropriateness of using software to
limit or establish the small UAS performance to meet the safety level
proposed in this rule.
7. Declaring Compliance
    The FAA agrees with the ARC recommendation that self-certification
is the appropriate method for manufacturers to declare compliance with
a performance standard. Self-certification, combined with the FAA's
determination that the means of compliance the manufacturer has used is
acceptable, will ensure the small UAS meets the appropriate safety
level the FAA proposes in this rule. In addition, the FAA's other
proposed measures for overseeing manufacturers, as described in section
IV.B.12, below, would result in a level of oversight and accountability
the FAA has determined is appropriate for manufacturers of small UAS
that certify eligibility to operate over people in accordance with this
proposed rule.
(a) Applicability to Manufacturers
    In this proposed rule, the FAA would consider a manufacturer to be
any person or entity that designs, produces, or modifies a small UAS
that is eligible to operate over people within the United States under
part 107. The FAA expects the most common form of manufacturer under
this proposed rule would be an entity that produces and sells a
complete and operable small UAS.
    Additionally, an entity that sells a kit that contains all the
components and parts from which to build an operable small UAS would be
considered a manufacturer. The kit would contain all the components
necessary to build the small UAS and would not require the owner to
purchase any additional materials to meet the requirements of this
proposed rule. A kit manufacturer would be required to test the
assembled, completed small UAS, rather than its component parts, to
demonstrate the small UAS satisfies the standard for Category 2 or 3
operations.
    A person who builds a small UAS from parts not provided as a kit
would also be a manufacturer under this proposal. For example, anyone
may purchase the component parts of a small UAS separately and build
small UAS themselves. The FAA would consider such a person to be a
manufacturer, and would require submission of a Declaration of
Compliance regarding the eligibility of the small UAS to conduct
Category 2 or 3 operations.
    A manufacturer would also be a person who modifies a small UAS
covered under an existing Declaration of Compliance to a condition that
is non-compliant with the original declaration. ``Non-compliant'' means
the small UAS has been altered such that it no longer matches the
configuration that was originally declared. Any person who makes this
kind of a change would be required to submit a new Declaration of
Compliance for the modified configuration(s) prior to conducting
operations over people within that category. Not all modifications
would cause a previously determined small UAS to become non-compliant,
however. A manufacturer may include a list of acceptable modifications
in the remote pilot operating instructions to ensure that a remote
pilot in command who may replace parts or otherwise modify the small
UAS is aware of which modifications would allow it to remain compliant
in the category to which compliance has been declared.
    Additionally, a manufacturer may be a person who modifies a small
UAS to be compliant with one or more categories of operations over
people. For example, this would include a person who modifies a small
UAS not previously eligible to conduct operations over people to a
small UAS that is eligible to conduct Category 2 or 3 operations over
people. Similarly, a person who modifies a small UAS that was
previously qualified to conduct only Category 2 operations so that it
may now conduct only Category 3 operations, by, for example, increasing
the weight of the small unmanned aircraft, would be a manufacturer. The
manufacturer identified on the most recent FAA-accepted Declaration of
Compliance would not carry the responsibility for the new configuration
of the small UAS that is the subject of the Declaration. Instead, the
person who made the modification assumes the role of the manufacturer.
A person making such modifications and still seeking to operate over
people would have to first

submit a new Declaration of Compliance.
    The FAA would not consider a person performing maintenance on a
small UAS, including replacement of components and parts in accordance
with the manufacturer's maintenance or operating instructions, to be a
manufacturer as long as the maintenance or replacement does not alter
the configuration or characteristics of the small UAS such that it no
longer meets its Declaration of Compliance. As a result, such a person
would not need to submit a new Declaration of Compliance. For example,
if a manufacturer provides replacement propellers with instructions on
how to install them, someone could install the parts in accordance with
the manufacturer's instructions. If the manufacturer, however, does not
provide or identify propellers in the remote pilot operating
instructions with specific maintenance instructions, the owner could
inadvertently become a manufacturer by virtue of replacing those
propellers with different replacement parts.
    The FAA applies the term manufacturer as described in this section
for the purposes of proposed subpart D of part 107 only. For example, a
UAS manufacturer that holds a type certificate (TC) or production
certificate (PC) would not be a manufacturer under this proposal
because the regulatory oversight for a TC/PC holder is codified at 14
CFR part 21. Rather, this discussion applies only to manufacturers of
non-type-certificated or non-production-certificated small UAS who
declare compliance with the standards of either Category 2 or Category
3 for operations over people.
(b) Declarations of Compliance
    For a small UAS to be eligible to conduct Category 2 or 3
operations over people, this proposed rule would require a manufacturer
to declare compliance with the impact kinetic energy and exposed
rotating parts standards applicable to aircraft eligible to conduct
Category 2 or 3 operations demonstrated through an FAA-accepted means
of compliance. The manufacturer would do this by submitting a
Declaration of Compliance via an electronic form available on the FAA's
website. For Category 1 operations, manufacturers would not be required
to submit a Declaration of Compliance.
    By submitting a Declaration of Compliance, a manufacturer would
also certify that it (1) established and maintained a process to notify
owners of small UAS and the FAA of any unsafe conditions that render
those small UAS non-compliant with proposed subpart D, (2) would
correct any safety defects the FAA identified, and (3) would allow the
Administrator to inspect its facilities, technical data, and any
manufactured small UAS and witness any tests necessary to determine
compliance with this subpart. As explained below in section
IV.B.7.b)(4), a manufacturer would be permitted to label its small UAS
for Category 2 or 3 operations after it receives notification of
acceptance of its Declaration of Compliance from the FAA.
(1) Contents of Declaration of Compliance
    The proposed Declaration of Compliance would be an electronic form
available on the FAA's website. A manufacturer interested in labeling a
small UAS as eligible for Category 2 or 3 operations over people would
submit a Declaration of Compliance to the FAA. A completed Declaration
of Compliance would include information the Administrator would require
for both determining that a small UAS complied with the regulation and
tracking those models of small UAS that were declared compliant with
the regulation. A manufacturer would declare compliance with the safety
level established by the impact kinetic energy and the exposed rotating
parts standards and include the following information:

     Means of compliance used,
     Name of the manufacturer,
     Physical address of the manufacturer,
     Email address of the manufacturer,
     Small UAS make and model
     Serial number or range of serial numbers for the small
unmanned aircraft (open-ended are permitted), and
     Whether the Declaration of Compliance was an initial or
an amended Declaration of Compliance.

    In the event a manufacturer is re-submitting the Declaration of
Compliance, the manufacturer would be required to include the reason
for such re-submittal. For example, the re-submittal could be to
correct a safety defect, or it could be to correct the misspelling of
the manufacturer's name or an incorrect address.
    The FAA would make information contained in Declarations of
Compliance publicly available. By posting the Declarations or otherwise
making the information in the Declarations publicly available, the FAA
and the public would be able to determine which make and model of small
UAS are eligible to conduct Category 2 and 3 operations over people.
(2) Declaring Compliance for Multiple Small UAS With the Same Make and
Model
    The FAA understands that manufacturers who are producing the same
make and model of small UAS on a large scale may not wish to perform
individual unit testing to demonstrate that each small UAS meets the
requirements of this proposal. The FAA would encourage these
manufacturers to establish and maintain a production quality system and
design configuration control system to provide for consistent
repeatability. Such a system would provide increased confirmation that
each individual small UAS meets the requirements of the category of
operations for which the manufacturer declared compliance, so that a
manufacturer could avoid testing every unit it constructed. If a
manufacturer utilizes a quality assurance system, the FAA would remain
confident that each unit subsequently manufactured would comply with
the proposed impact kinetic energy, exposed rotating parts, and safety
defects standards.
(3) Multiple Categories of Operation
    This proposal would also allow a manufacturer to design a small UAS
that could meet the performance requirements of multiple categories of
operations over people. If a manufacturer conducts testing or engages
in analysis or inspection to determine a small UAS could meet the
requirements for operations in both Category 2 and Category 3 in the
appropriate modes or configurations, the small UAS manufacturer would
need to submit only one Declaration of Compliance to the FAA. On that
Declaration of Compliance, the manufacturer would identify the
categories of operation for which it determined the small UAS was
compliant, and the means of compliance used for each category.
(4) FAA Acceptance of Declaration of Compliance
    This proposed rule would require a manufacturer to provide
information on its Declaration of Compliance regarding whether it has
used an FAA-accepted means of compliance or a custom means of
compliance the FAA has not yet accepted. A manufacturer would label its
small UAS for Category 2 or 3 operations once it receives notification
of acceptance of its Declaration of Compliance from the FAA. Once the
FAA accepts a Declaration of Compliance, the FAA would make the
Declaration of Compliance, or

information from the Declaration, publicly available.
    If a manufacturer uses a custom means of compliance that the FAA
has not yet accepted, the FAA must review and accept the means of
compliance before it accepts the Declaration of Compliance. This could
result in additional review time prior to acceptance of the Declaration
of Compliance. The FAA would notify the manufacturer upon its decision
regarding acceptance of the custom means of compliance and Declaration
of Compliance.
(5) Modifying a Small UAS and Resubmitting a Declaration of Compliance
    Any person who modifies a small UAS in a way that could affect the
eligibility of the small UAS to operate over people under Category 2 or
Category 3 of this proposed rule would be required to submit a new
Declaration of Compliance before the small UAS could be operated over
people. This requirement would not apply to those situations in which
an individual performs a modification that the manufacturer identifies
in the remote pilot operating instructions as an allowable change or
modification for that small UAS, as discussed in section IV.B.9. When a
manufacturer seeks to submit a Declaration of Compliance for a small
UAS that was not previously eligible for operations over people,
however, the FAA would undertake the same review process to verify the
small UAS fulfills the performance-based standards described
previously.
    The requirement to submit a new Declaration of Compliance would
ensure any small UAS operated under this framework meets the applicable
requirements for operations over people. In this way, the FAA would
have the ability to track the responsible manufacturer as well as any
modifications that the small UAS may undergo during its lifetime. For
these reasons, the FAA would require any person who modifies a
previously declared small UAS to take on the responsibilities of a
manufacturer and submit a new Declaration of Compliance if the
modification took the small UAS outside the configuration originally
declared.
(6) Rescission Process
    Under this proposed rule, the FAA would rescind a manufacturer's
Declaration of Compliance if the agency becomes aware that a small UAS
for which a manufacturer has declared compliance is no longer qualified
for operations over people. The FAA is proposing new procedural rules,
described below, to govern any action to rescind a Declaration of
Compliance. Therefore, the FAA's rules under 14 CFR part 13 would not
apply.
(a) Notification of Safety Issues
    The FAA proposes in Sec.  107.135(c) that it would notify the
manufacturer when the FAA becomes aware of a safety issue that could
affect a manufacturer's Declaration of Compliance, either because the
small unmanned aircraft is not compliant with the exposed rotating
parts or kinetic energy standards, or because the small UAS has a
safety defect as described in section IV.B.11. (a). If a safety issue
arises in which the small UAS no longer fulfills the safety level set
forth in this proposed rule, either by way of a safety defect,
material, component, or feature on the small UAS, then the manufacturer
must notify the FAA. At that point, the manufacturer would have the
opportunity to discuss the potential safety issue with the FAA. As a
result of such a discussion, the FAA may determine that a safety issue
does not actually exist, that the manufacturer has incorporated an
adequate mitigation to address and correct the safety issue, or that a
safety issue still exists.
(b) Proposed Rescission of a Declaration of Compliance
    If the FAA determines, as a result of the discussion described
above, that a safety issue remains unaddressed, the FAA would send the
manufacturer a notice of proposed rescission of a Declaration of
Compliance. The notice would set forth the agency's basis for the
proposed rescission and provide the manufacturer 10 business days to
submit evidentiary information to refute the proposed notice of
rescission.
(c) Notice of Rescission of a Declaration of Compliance
    After receiving a proposed notice of rescission, a manufacturer may
provide information demonstrating the small UAS meets the requirements
of this part within 10 business days. If a manufacturer fails to
establish that a safety issue does not exist, or if the manufacturer
fails to respond within 10 business days, the FAA would issue a notice
rescinding the Declaration of Compliance. At this point, the FAA would
publish this rescission. The FAA would also specify on its website for
which category the Declaration of Compliance has been rescinded. Remote
pilots in command would not be permitted to operate the particular
small UAS over people if the FAA has rescinded the Declaration of
Compliance.
    If the FAA rescinds a Declaration of Compliance as a result of a
safety issue, a manufacturer would be able to modify the small UAS such
that the safety issue is resolved, at which point the manufacturer
could submit a new Declaration of Compliance. The FAA would review the
new Declaration of Compliance and notify the manufacturer of whether
the FAA has deemed it acceptable.
(d) Petition for Reconsideration of a Rescission of a Declaration of
Compliance
    Once a Declaration of Compliance is rescinded, a manufacturer would
have the opportunity to petition the FAA for reconsideration. A
manufacturer seeking reconsideration under this rule must petition the
FAA within 60 days of the date of issuance of the notice of rescission.
The petition would have to show: (1) The lack of a material fact in the
original response to the notification of the safety issue, and address
why that fact was not present in the original response; (2) an
important factual error existed in the decision to rescind the
Declaration of Compliance; or (3) the FAA did not correctly interpret a
law, regulation, or precedent. The FAA would consider this petition and
issue a final agency decision either affirming or withdrawing the
rescission of the Declaration of Compliance. A manufacturer could
appeal the final agency decision as provided in 49 U.S.C. 46110.
(e) Emergency Rescission of a Declaration of Compliance
    Prior to rescission of a Declaration of Compliance, the FAA would
typically initiate the safety issue notification process with the
manufacturer as discussed previously. However, if the Administrator
determines an emergency exists and safety of persons on the ground
requires an immediate rescission of a Declaration of Compliance, the
FAA may exercise its authority under 49 U.S.C. 46105(c) \81\ to issue
an emergency order rescinding a Declaration of Compliance. Under these
circumstances, rescission would go into effect immediately, prior to
the FAA initiating the notification process or the rescission
procedures described above. The order would remain in effect until the
basis for issuing the order no longer

exists. The emergency order would be considered a final agency
decision; as such, a manufacturer may appeal the decision as provided
in 49 U.S.C. 46110 following the issuance of the order.
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    \81\ When the Administrator determines that an emergency exists
related to safety in air commerce and requires immediate action, the
Administrator may issue an immediately effective order to meet the
emergency, with or without notice. 49 U.S.C. 46105(c).
---------------------------------------------------------------------------

8. Recordkeeping Requirements
    This proposed rule would require manufacturers maintain small UAS
records related to their Declarations of Compliance for a minimum of
two years after ceasing production. The FAA also proposes to require
manufacturers to retain the substantiating data for a custom means of
compliance for as long as the means of compliance remains accepted. In
the event of a safety defect, or if the FAA initiated an action against
a manufacturer, this information would be critical to determine the
cause, scope, and severity of the defect or infraction. The FAA
requests comment on the appropriateness of this proposed amount of time
for record retention.
    For a Declaration of Compliance that uses an accepted means of
compliance, the manufacturer would keep substantiating data that
includes a description of the method used to demonstrate compliance as
well as the results. Specifically, if the manufacturer established
compliance by testing, the manufacturer would retain detailed
information on the test method and the results used to demonstrate the
small UAS meets the applicable impact kinetic energy and exposed
rotating parts standards.
    For a custom means of compliance submitted independently of a
Declaration of Compliance, the submitter would keep:

     Test procedures that outline the test methodology (if
the manufacturer established compliance by testing);
     An analysis or record of inspection to establish the
equivalency of the means of compliance to the safety level
identified in this proposal; and
     Substantiating data that supports the test (if
applicable), methods, results and conclusions.

    This information would likely include details on the method and the
results the submitter used to demonstrate the small unmanned aircraft
meets the applicable impact kinetic energy and exposed rotating parts
standards. Substantiating data could include detailed information on
whether the testing or analysis was done consistent with accepted
methods used by the medical industry, consumer safety groups, or other
peer-reviewed test methods. Such information should also indicate
whether the proposed means of compliance required unreasonable skill or
mitigation to meet the requirements.
    For a Declaration of Compliance that uses a custom means of
compliance that requires direct FAA review, a manufacturer would keep
both the records for its Declaration of Compliance and its custom means
of compliance, as discussed above. The FAA may require access to that
information in several types of situations. For example, if the FAA
rescinded a Declaration of Compliance, it may request the original set
of substantiating data from a manufacturer if a manufacturer elects to
correct the safety issue and submit a new Declaration of Compliance for
the same small UAS. Upon resubmittal, the FAA would likely require all
substantiating data from prior to the identification of the safety
issue, as well as supporting data after anyone had made modifications.
Additionally, if a manufacturer submitted a Declaration of Compliance
and identified a custom means of compliance the FAA had not previously
accepted, the FAA would require the manufacturer to submit
substantiating data to facilitate the FAA's review of the means of
compliance.
9. Remote Pilot Operating Instructions
    In order to operate a small UAS safely over people, the remote
pilot in command would be responsible for knowing what category of
operations his or her small UAS is eligible to conduct, and what
technical and operational limitations apply to the operations.
Accordingly, the FAA proposes to require manufacturers to provide
remote pilot operating instructions with product-specific information
related to operations over people that would occur in Category 2 or
Category 3.
    This proposed requirement is consistent with the ARC's
recommendation. Specifically, the ARC recommended small UAS
manufacturers provide operating manuals to the operators of the small
UAS that would include operating instructions for Category 2 and 3
operations.\82\ The ARC did not provide any information regarding the
contents of the operating manual, leaving that determination to future
voluntary consensus standards. The ARC recommended the FAA require the
operator to comply with the operating manual.
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    \82\ ARC Report at 7-8. The FAA uses the term ``remote pilot
operating instructions'' in this proposal in lieu of the ARC's
suggested term of ``operating manual,'' to avoid confusion with
manned aircraft flight manuals.
---------------------------------------------------------------------------

    This rule proposes to require manufacturers to provide operating
instructions upon sale, transfer, or use of the aircraft by someone
other than the manufacturer. This requirement would apply to anyone who
is a manufacturer for the purposes of this proposed rule, as described
above in section (IV.B.7.(a). In addition, the manufacturer would be
required to keep the instructions up-to-date to account for any changes
it makes to an aircraft over time.
    Specifically, the FAA proposes in Sec. Sec.  107.115(b)(3) and
107.120(b)(3) that the remote pilot operating instructions include, at
a minimum, the following information:

     General information, including system description and
system limitations, and the category or categories of operations
over people for which the manufacturer of the small UAS has declared
compliance;
     If modifications of the small UAS can occur, those
modifications the manufacturer has determined do not bring the small
UAS out of compliance with the category declared; and
     If the small UAS has variable modes or configurations,
information regarding those modes or configurations.

    Existing regulations require remote pilots to conduct a preflight
inspection and ensure that the small UAS is in a condition for safe
operation.\83\ These existing regulations would continue to apply to
operations over people conducted under the terms of this proposed rule.
The additional information contained in the remote pilot operating
instructions would serve to inform a remote pilot in command of the
characteristics of the small UAS, which in turn would assist the remote
pilot in conducting his or her preflight check and ensuring the small
UAS is in a condition for safe operation prior to conducting a Category
2 or 3 operation.
---------------------------------------------------------------------------

    \83\ The remote pilot in command must check the small UAS to
ensure it is in a condition for safe operation prior to each flight.
14 CFR 107.15(a). Further, no person may continue flight of the
small unmanned aircraft when he or she knows or has reason to know
that the small UAS is no longer in a condition for safe operation.
Sec.  107.15(b). Section 107.49(a) requires that, prior to flight,
the remote pilot in command must assess the operating environment,
considering risks to persons and property in the immediate vicinity
both on the surface and in the air. This assessment must include
becoming aware of: (1) Local weather conditions; (2) local airspace
and any flight restrictions; (3) the location of persons and
property on the surface; and (4) other ground hazards. The preflight
assessment must also include verification that all control links
between the ground control station and the small unmanned aircraft
are working properly. 14 CFR 107.49(c). Finally, Sec.  107.49
requires that, if the small UAS is powered, the remote pilot in
command must ensure that there is enough available power for the
small UAS to operate for the intended operational time.
---------------------------------------------------------------------------

    Manufacturer-required components that make up the small UAS must be
listed in the remote pilot operating instructions to help the remote
pilot ensure that all components of the small UAS are present. This is
necessary

because, if a small UAS is missing any components, the small UAS would
not comply with the category of operations over people for which the
manufacturer declared compliance. A manufacturer must also clarify the
category or categories of operations over people for which the small
UAS is eligible.
    The FAA proposes requiring in Sec. Sec.  107.115(b)(3)(ii) and
107.120(b)(3)(ii) that a manufacturer include in the remote pilot
operating instructions all modifications the manufacturer has
determined would not change the ability of the small UAS to meet the
requirements for the category of operation for which the manufacturer
declared compliance. The FAA acknowledges that modification of a small
UAS is a routine event for some remote pilots. Some modifications may
not change the flight characteristics of the small unmanned aircraft;
for example, replacing one camera with another that has the same weight
and size but better optics. However, changing small unmanned aircraft
components such as propellers or other articles necessary for flight
may change the flight characteristics of the small unmanned aircraft,
and could potentially change the small UAS eligibility to conduct
operations over people.
    The modifications described in proposed Sec. Sec.
107.115(b)(3)(ii) and 107.120(b)(3)(ii) could consist of adding or
exchanging products and evaluating them based on characteristics such
as weight, size and shape. For example, a manufacturer could list
certain makes and models of payload cameras, or provide weight and size
limits along with a generic shape description. A remote pilot would
then be able to switch out any payload cameras that meet the described
parameters and continue to operate over people. The manufacturer would
have to ensure, through an accepted means of compliance, that the small
UAS with the included modifications would remain in compliance with the
performance-based requirements for the applicable categories of
operations. If a person modified a small UAS in a manner not included
in the remote pilot operating instructions, the small UAS may no longer
comply with its associated Declaration of Compliance. This is because
if a person changed anything related to design, performance,
coefficient of drag, or energy-absorbing materials, the original test
results or analyses concerning the transfer of impact kinetic energy
could change, and such alteration could change the category of
operations or cause the small UAS to exceed the applicable standard.
The same principle would apply concerning the presence of exposed
rotating parts. Therefore, should a person make a modification that is
not listed in the remote pilot operating instructions, the FAA would
consider that person as the new manufacturer of the small UAS, and
would require compliance with manufacturer requirements to operate the
aircraft over people.
    The remote pilot operating instructions must also state whether the
small UAS has modifications that will change the determination of the
small UAS fulfilling the standard for the category of operation the
small UAS is eligible to conduct. For example, a manufacturer may add
an interchangeable camera to the small unmanned aircraft that would
affect the small unmanned aircraft's eligibility for operating over
people in Category 2 or 3 operations.\84\ By this proposed rule, the
FAA would require the manufacturer to inform remote pilots of the
effect of such options to the extent the exercise of those options may
affect compliance with the applicable standards. Without this
information, a person could change the flight characteristics of the
small unmanned aircraft and make it non-compliant with Category 2 or 3
requirements.
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    \84\ As discussed in section IV.B.5. (b), manufacturers must
submit a declaration of compliance that identifies a means of
compliance the FAA has accepted. When verification of compliance
assumes the presence of a component affixed to the aircraft, the FAA
must receive information concerning this because it would likely
affect the mass of the small unmanned aircraft.
---------------------------------------------------------------------------

    For a small UAS that has variable modes or configurations, the FAA
would require a manufacturer to provide instructions on how to verify
what mode or configuration the small UAS is in, and how to switch
between modes or configurations. This information would facilitate a
remote pilot's verification that his or her small UAS is in the correct
mode or configuration to conduct a certain category of operations over
people. Similarly, if a remote pilot chooses to operate in a different
category of operations over people, or in a mode or configuration that
is not permitted for operations over people but is permitted under part
107, he or she could consult the remote pilot operating instructions to
determine how to change the mode or configuration to the desired
settings.
    The FAA would not require the manufacturer to provide remote pilot
operating instructions in a particular format. For example, a
manufacturer could choose to provide the operating instructions as part
of the packaging of a small UAS, make them available electronically, or
provide them in some other way. Manufacturers with products currently
on the market would be free to choose whether to incorporate the
instructions into existing materials, or they could create a new set of
instructions that are specific to operations over people. For products
in production before this rule is finalized but subsequently declared
to be in compliance and eligible for operations over people, the
manufacturer would be responsible for developing remote pilot operating
instructions and making them available to remote pilots and owners. The
FAA would not prescribe the method for making the instructions
available, but acknowledges publishing them online would be an
efficient and effective way.
    Although the FAA does not propose requiring the remote pilot
operating instructions to contain information in addition to the items
enumerated above, the FAA encourages small UAS manufacturers to provide
additional operational information to remote pilots. Examples of such
information appear in Advisory Circular 107-2, which accompanies this
NPRM.
10. Labeling Requirements
    The FAA proposes to require that manufacturers label any small
unmanned aircraft that are qualified for Category 2 or 3 operations
over people. Such labeling would assist the FAA in its oversight role
by providing a simple and efficient way to determine whether an
operation is consistent with this proposal. In addition, it would
provide notice to the remote pilot of which category of operations he
or she is eligible to conduct using that aircraft.
    In its report, the ARC recommended a manufacturer of a small UAS
``label the product or product retail packaging in accordance with
industry consensus standards,'' \85\ and that the operator be
responsible for knowing the category in which his or her small UAS
qualifies to operate. Therefore, the operator would presumably know
which operating limitations he or she must follow. The proposed
labeling requirement would assist the FAA in its oversight role because
it provides an efficient means for an inspector to evaluate whether an
operation is consistent with the category or categories of operation
the small UAS may conduct. Because Category 3 operations would entail
unique operating limitations, the label on small unmanned aircraft
eligible to conduct Category 3 operations would indicate to the remote
pilot that he or she must

adhere to the applicable operating limitations.\86\
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    \85\ ARC Report at 10.
    \86\ The labeling requirement this rule proposes is not the sole
means by which a remote pilot in command will be aware of the
operating limitations applicable to Category 3 operations. Remote
pilots in command must maintain awareness of updated regulations, as
required by proposed Sec. Sec.  107.73(a) and 107.74(a) in this
rule. As a result, initial knowledge testing and recurrent training
implemented after the effective date of a final rule implementing
this proposed rule would include operations over people as a subject
area on both the test and training.
---------------------------------------------------------------------------

    The FAA is not proposing a specific location for label placement
due to the numerous design variations of small unmanned aircraft. In
the case of very small unmanned aircraft, manufacturers may need to
exercise creativity in determining the location best suited to
satisfying the proposed labeling requirement. Labeling a non-critical
surface would likely prevent wear and removal during normal operations.
    The FAA declines to propose a prescriptive labeling requirement
that specifies exactly how a manufacturer must label an aircraft, what
size font to use, and so on. Due to the large variety of small UAS
models that exist, such a prescriptive requirement would be
unnecessarily limiting for manufacturers. Instead, a manufacturer could
label the aircraft by any means as long as the label is in English,
legible, prominent, and permanently affixed to the aircraft. For
example, a manufacturer could use the following labels: ``Category 2'',
``Category 3'', ``Cat. 2'', or ``Cat. 3''.
    Given that a small UAS could be qualified to conduct more than one
category of operations, the FAA proposes requiring a manufacturer label
the small UAS with each category of operations the small UAS is
qualified to conduct. For example, a small UAS qualified to conduct
Category 2 operations may also be qualified to conduct Category 3
operations. The manufacturer would label such a small UAS with each
category, as follows: ``Cat. 2, 3'' or ``Category 2, 3''. The label
could be painted onto, etched into, or affixed to the aircraft by some
other permanent means.
    Some small UAS manufactured prior to final publication of this rule
may qualify for a category of operations over people. In a situation in
which a manufacturer declared a previously existing make/model of small
UAS eligible for Category 2 or 3 operations and has provided remote
pilot operating instructions as described in section IV.B.9., the
remote pilot could then label that small unmanned aircraft in
accordance with the Declaration of Compliance.
    In addition to the proposed requirement that a manufacturer label
the aircraft, the FAA also proposes requiring a remote pilot ensure his
or her small unmanned aircraft is properly labeled before conducting
any operations over people. A clear and legible label will enable a
remote pilot, an inspector, or a member of the public to identify the
types of operations a small UAS may conduct. If a label degrades such
that it is no longer legible or attached to the aircraft, the remote
pilot is responsible for providing a new label before operating over
people. The proposed labeling requirement would apply regardless of
whether a person obtains a small UAS directly from a manufacturer or as
a subsequent transfer. No pilot would be able to operate the small UAS
over people unless he or she verifies the label meets the requirements
of this rule.
11. Manufacturer Accountability
    After a manufacturer has declared that a specific small UAS
fulfills the standard of a particular category, this proposal would
require the manufacturer to monitor the small UAS to ensure it complies
with the requirements of this subpart. Specifically, a manufacturer
should monitor the validity of the means of compliance used to ensure
the continued fulfillment of the safety level the standards at
Sec. Sec.  107.115(b)(1) and 107.120(b)(1) establish. The manufacturer
should also track the construction, related safety analysis, and
service history to ensure they do not reveal any hazardous conditions
or safety defects that could increase the risk of a small UAS operation
over people. Moreover, the manufacturer has a continuing obligation to
ensure that the remote pilot operating instructions satisfy the
regulatory requirements. To satisfy these obligations, a manufacturer
may have to monitor its manufacturing processes, small UAS operational
usage, and collection of accident and incident data. Manufacturer
monitoring could also include information that owners and operators of
the small UAS provide. Should the FAA identify a safety issue that
warrants review of a manufacturer's data, records, or facilities, a
manufacturer would be required to grant such access.
(a) Safety Defects
    The FAA proposes to require that a manufacturer build a small UAS
qualified to conduct Category 2 or 3 operations such that it does not
contain any safety defects. For the purposes of this proposal, a safety
defect refers to a material, component, or feature on a small UAS that
increases the likelihood that the small UAS could cause a casualty or
fatality to a person during an operation over people. Under this
proposal, a safety defect would cause a small UAS to exceed a low
probability of causing a casualty (Category 2) or a fatality (Category
3) to a person during an operation over people. For example, exposed
wires or hot surfaces on a small unmanned aircraft could cause
electrocution or burns to a person upon impact. Many small unmanned
aircraft utilize lithium polymer or lithium-ion batteries as the
primary energy source; damaged or defective batteries could cause
casualties from battery fires or explosions. Sharp edges or projections
on a small unmanned aircraft could cause lacerations or puncture wounds
as a result of an impact with a person. As small UAS designs evolve
over time, potentially hazardous features or characteristics, unknown
at the present time, could emerge.
    The FAA would identify safety defects through a variety of means.
The FAA may receive consumer complaints, industry safety bulletins, or
an individual manufacturer's notification that a safety defect has
arisen. Once the FAA has formally identified a safety defect, it would
notify the manufacturer of the defect. The manufacturer would have an
opportunity to respond by either correcting the defect or demonstrating
the small UAS does not contain any materials, components, or features
that increase the probability of casualty or fatality for the category
of operations for which the manufacturer declared the small UAS as
compliant. If the manufacturer is unable to demonstrate the small UAS
does not contain any safety defects, the FAA may initiate proceedings
to rescind the manufacturer's Declaration of Compliance.
    As an ongoing requirement, manufacturers would be responsible for
correcting any safety defects they identify after manufacturing the
small UAS, to ensure continued qualification for Category 2 or 3
operations. In the event the FAA rescinds a Declaration of Compliance,
no small UAS covered by that declaration could operate over people. The
small UAS could resume operations only after the FAA reinstates
acceptance of the Declaration of Compliance, accepts an amended
Declaration of Compliance, or accepts a new Declaration of Compliance
that applies to that small UAS. Either the original or a subsequent
manufacturer could submit a new Declaration of Compliance in accordance
with this proposed rule.

    The FAA would publish any final rescission of a Declaration of
Compliance on the FAA website, and may publish notification of the
safety defect in the Federal Register as a Notice of Availability.
These actions would serve two purposes: First, to notify remote pilots
that the identified aircraft are no longer safe to conduct operations
over people and second, to put manufacturers on notice not to
incorporate the material, component, or feature into any future small
UAS a manufacturer wishes to qualify for Category 2 or 3 operations
over people without appropriate mitigations. The FAA notes the
rescission of a Declaration of Compliance would not render a small UAS
inoperable, but rather only unsafe for operations over people. The FAA
seeks comment on whether this process provides sufficient opportunity
for notice and comment for manufacturers aside from those whose
products the safety directive directly implicates, and whether the
process provides the public sufficient opportunity for notice and
comment.
    If the FAA rescinds a Declaration of Compliance, the FAA would
publish the applicable makes and models of small UAS that are no longer
eligible to operate over people. Remote pilots would be required to
refrain from using those aircraft to operate over people until the
manufacturer institutes an acceptable correction. To correct a safety
defect, a manufacturer could develop a correction and test the aircraft
to ensure the aircraft does not increase the probability of causing a
casualty or fatality when operated over people with the correction. The
manufacturer would then submit a new Declaration of Compliance to the
FAA identifying the means of compliance the manufacturer used to
correct the safety defect.
    Alternatively, the owner or remote pilot of a small UAS may elect
to correct a safety defect associated with his or her aircraft. Should
any person choose this option, he or she could submit a Declaration of
Compliance to the FAA identifying the means of compliance used to
correct the safety defect. That person, by means of modifying the small
UAS such that it is again in compliance with the operation over people
requirements, would become the manufacturer of his or her specific
small UAS, and would assume all responsibilities that apply to
manufacturers under this proposal.
(b) Public and FAA Notification Process
    This proposed rule would require a manufacturer to certify on its
Declaration of Compliance that it has established a process to notify
the public and the FAA if the manufacturer identifies an issue with its
small UAS that would render the small UAS ineligible for operations
over people. Reporting a safety defect to the FAA would not
automatically result in the rescission of a Declaration of Compliance.
The FAA would evaluate the report and correspond with a manufacturer to
determine whether taking corrective action or rescission would be
appropriate.
    A manufacturer must notify the FAA of any safety issues it
identifies. Reporting such issues would both assist the FAA in
discovering product hazards and identifying risks of injury the FAA
could address through direct communication with manufacturers,
publication of Notices of Availability in the Federal Register, or
education. Manufacturers' reporting would provide a timely and
effective source of information about small UAS because manufacturers
often learn of potential product safety problems at an early stage. For
this reason, this proposed rule would require manufacturers to develop
a system for maintaining and reviewing information about their products
that might identify when their product may have a defect that increases
the probability of causing injury during operations over people. Such
information would include, but is not limited to, consumer complaints,
warranty returns, insurance claims or payments, product liability
lawsuits, reports of production problems, product testing, or other
critical information concerning their products.
    Subsequent to manufacturers' discovery of noncompliance, this rule
would require manufacturers notify the FAA and the public of the
existence of the safety defect. Manufacturers' notification to the FAA
should describe the nature of the noncompliance and how the
manufacturer plans to address it. As stated above, such notification
would not automatically result in the rescission of the Declaration of
Compliance, but would involve the FAA corresponding with manufacturers
to resolve the issue to ensure safety.
    Notification to the public and owners of that make/model would also
be a critical step in ensuring continued safety. Such notification
could take the form of a notice on a manufacturer's website, electronic
notification to owners who have registered the small UAS with the
manufacturer, or an update to the small UAS software advising the
remote pilot of the change in status. The FAA encourages manufacturers
to exercise diligence to ensure the intended audience receives
communications involving any potentially non-compliant conditions. In
this regard, the FAA encourages manufacturers to design and utilize a
system that would facilitate communication between the manufacturer and
the owners of the small UAS and would successfully inform members of
the public at large. In general, the FAA contends potential consumers
and the public have an important interest in being aware that proximity
to a particular small unmanned aircraft may pose an undue hazard.
(c) Falsification
    As defined in this proposal, a Declaration of Compliance would be a
record submitted by a manufacturer for a small UAS that certifies the
small UAS is eligible for operations pursuant to Category 2 or Category
3 under subpart D of this part. Records are subject to compliance with
the falsification provisions of the existing terms of Sec.  107.5.
These provisions prohibit any fraudulent or intentionally false record
from being made, kept, or used to show compliance with any requirement
of part 107. Accordingly, falsifying any part of any record intended to
constitute proof of compliance with manufacturer requirements under
this proposal could subject the person who submitted the record to a
civil penalty, and would be a basis for rescinding a Declaration of
Compliance.
(d) Access to Facilities
    Under this proposed rule, a manufacturer must grant the FAA access
to its facilities upon the FAA's request as described in Sec.  107.7,
to validate compliance with this subpart. As part of a manufacturer's
Declaration of Compliance, the manufacturer would agree to allow the
FAA to inspect its facilities, technical data, and any manufactured
small UAS and witness any tests necessary to determine compliance with
this subpart. Some occurrences may necessitate facility inspection. For
example, facility access would likely become necessary when the FAA and
the manufacturer are working together to address a safety defect.
(e) FAA Publication of Status of Declarations of Compliance
    The FAA proposes making available on the FAA website the status of
each manufacturer's Declaration of Compliance for public access to
enable remote pilots to determine which small UAS (by make, model,
serial number, and/or category declared) are eligible for operations
over people. If the FAA rescinds a Declaration of Compliance,

the FAA would notify the public of the rescission and would identify
the small UAS associated with the rescinded Declaration of Compliance
as no longer eligible for operations over people. In this way, remote
pilots would be aware of whether the model of small UAS they are
utilizing was eligible for operations over people.
12. Operational Requirements and Remote Pilot Restrictions
    The FAA proposes to include in Sec.  107.49 a requirement that a
remote pilot ensure he or she is using a small UAS eligible to conduct
an operation over people. This verification would need to occur as part
of the pre-flight inspection. Advisory Circular 107-2 would include
updates with suggestions concerning the pre-flight procedures a remote
pilot could follow to be compliant with this proposed rule.
    As a general matter, the FAA acknowledges pilot experience may be
relevant in determining whether the operation of a small UAS qualified
to operate in either Category 2 or 3 adheres to the safety level the
FAA contemplates in this proposed rule. In this regard, the ARC
recommended that remote pilots conducting operations over crowds be
required to have more training or experience than other pilots, but did
not recommend specifically what such training or experience would
involve. The FAA sees value in an experience requirement, however, at
this time, lacks information and data to assess how much training or
time piloting a particular aircraft is warranted. In order to gather
information on what mitigations would be appropriate, the FAA requests
comments on the following questions: To conduct operations over open-
air assemblies using a small unmanned aircraft that can transfer up to
25 ft-lbs kinetic energy to a person upon impact, should the remote
pilot-in-command have additional skills, experience, or currency beyond
what part 107 currently requires? If so, what kind of skill,
experience, or currency should be required (e.g., minimum time
operating the small UAS to be used, minimum number of take offs and
landings, etc.)? How should that skill, experience, or currency be
documented? The FAA will consider carefully all input it receives on
this topic.
    To conduct Category 1 operations, Sec.  107.110 would require a
remote pilot to ensure the small unmanned aircraft weighs 0.55 pounds
or less on takeoff and for the duration of the flight, including
everything that is on board or otherwise attached to the aircraft. To
confirm a small UAS aircraft is eligible to conduct Category 1
operations, a remote pilot could weigh the aircraft. To conduct