ASTM F3389/F3389M-21

Standard Test Method for Assessing the Safety of Small Unmanned Aircraft Impacts

SIGNIFICANCE AND USE
5.1 The test method is intended to be used by sUAS manufacturers, sUAS operators, and CAAs to assess the safety of sUA impacts to people on the ground during operations involving flight over people.  
5.2 The test method provides a framework for creating new designs and evaluating existing designs to determine the sUA’s blunt force trauma injury potential to the head or neck, or both, during a collision with a person on the ground.  
5.3 Applicants can determine whether to use Methods A, B, C, or D based upon their specific sUA characteristics, flight operations, and CAA requirements. In some cases, sUA with low impact KE below 54 ft-lbf [73 J] may not require rigorous testing to ensure safety to the nonparticipating public and can use Method A. Vehicles with higher impact KEs should conduct impact testing using Method B, Method C, or Method D. Method B is simpler than Method C and, therefore, less costly for the applicant. Method B results may be more conservative since the test setup is more rigid and can result in an increase in the amount of energy transferred during the impact than the injury metrics established using a full ATD. Method C testing is costlier and schedule-intensive, but provides a higher level of certainty of the injury potential of the sUA and is more directly comparable to established automotive injury metrics and injury metrics derived from ATD testing and used by the governing CAA. Method D allows for the direct comparison to energy-based requirement of some CAAs.  
5.4 The output of Method A is a verification that the sUA or sUA with mitigation does not exceed the 54 ft-lbf impact KE throughout its flight envelope based upon flight test data as means of obtaining approval for flight over people for Category 2 or 3 operations for the FAA. Other governing CAAs may only require a weight metric or other impact energy metric in lieu of the 54 ft-lbf impact KE.  
5.5 The output from Methods B and C is a characterization of the forces (measure...
SCOPE
1.1 This test method is applicable to small unmanned aircraft (sUA) that are limited in the United States in accordance with 14 CFR § 107.3 to be less than 55 lbf. The test method provides a standardized method for assessing the safety of sUA impacts with a person on the ground. Results from testing using Methods A, B, C, or D are intended to be used to support an applicant in obtaining permission from the governing Civil Aviation Authority (CAA) for flight over people. Approval of reports for the conduct of tests and the decision to grant permission rests with the governing CAA based upon adherence to the methodologies outlined in this test method.  
1.2 This test method is based on methods researched by the FAA Center of Excellence for Unmanned Aircraft Systems (UAS) supported by the Alliance for System Safety of UAS through Research Excellence (ASSURE). These methods expand on extensive research and testing conducted by the automotive industry to support quantitative automotive passenger safety standards and testing and test data on sUA collected by ASSURE.  
1.3 The purpose of this test method is to define a method to establish confidence in the overall injury potential of a particular sUA configuration under probable failure conditions. This testing is not meant to simulate the worst possible impact for the most conservative set of the population. It is expected that CAAs should determine what injury thresholds are acceptable under their public policy and determine operational limitations for various operations by using the data from this testing in conjunction with the specific concept of operations proposed by the applicant.  
1.4 The test method provides four methods for evaluating the potential for impact injury: a simple analytical method, a simplified test, a more rigorous test, and a test method normed to approximate energy transfer values with appropriate safety margins applied to each approach to address...

General Information

• Status: Published
• Publication Date: 31-Aug-2021
• ICS: 49.020 - Aircraft and space vehicles in general
• Technical Committee: F38 - Unmanned Aircraft Systems
• Drafting Committee: F38.01 - Airworthiness

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: F3389/F3389M − 21
Standard Test Method for
1
Assessing the Safety of Small Unmanned Aircraft Impacts
ThisstandardisissuedunderthefixeddesignationF3389/F3389M;thenumberimmediatelyfollowingthedesignationindicatestheyear
of original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.
A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 1.5 The applicant should understand the actual operating
characteristicsoftheirsUAbeforestartingtheprocessoutlined
1.1 This test method is applicable to small unmanned
in this test method. It is assumed that the applicant is able to
aircraft (sUA) that are limited in the United States in accor-
substantiate the most probable, worst-case (MPWC) impact
dance with 14 CFR § 107.3 to be less than 55 lbf. The test
orientationofthesUA;typicalandmaximumoperatingheights
methodprovidesastandardizedmethodforassessingthesafety
and speeds; and terminal velocity of their sUAas a function of
of sUA impacts with a person on the ground. Results from
altitude to compare the results of the impact analysis with the
testing using MethodsA, B, C, or D are intended to be used to
proposedoperationforthesUA.Thistestmethodisintendedto
support an applicant in obtaining permission from the govern-
supplement the verification requirements of Specification
ing Civil Aviation Authority (CAA) for flight over people.
Approval of reports for the conduct of tests and the decision to F3298 and Specification F3322, as well as a supplement to
grant permission rests with the governing CAA based upon Specification F2910. This test method should not be used as a
adherence to the methodologies outlined in this test method.
stand-alone document without consideration of other ASTM
UAS standards.
1.2 This test method is based on methods researched by the
FAA Center of Excellence for Unmanned Aircraft Systems
1.6 These methods assume that a blunt force head impact is
(UAS) supported by the Alliance for System Safety of UAS
the most likely injury mechanism leading to serious injury or
through Research Excellence (ASSURE). These methods ex-
fatalities. The level of blunt force injury to the head may be
pand on extensive research and testing conducted by the
adjusted for various applications (such as sUA operations
automotiveindustrytosupportquantitativeautomotivepassen-
around first responders with helmets) and compared with the
ger safety standards and testing and test data on sUAcollected
amount of force or load factor that the sUAtransfers during a
by ASSURE.
collision.
1.3 The purpose of this test method is to define a method to
1.7 Method B is not appropriate for foam-built fixed-wing
establish confidence in the overall injury potential of a particu-
sUAdue to the stiffness of the FAAHybrid IIIATD Head and
lar sUA configuration under probable failure conditions. This
Neck. Until a different impactor can be developed for Method
testing is not meant to simulate the worst possible impact for
B, these sUA should use Method C or D for evaluation.
the most conservative set of the population. It is expected that
CAAs should determine what injury thresholds are acceptable
1.8 Units—The values stated in either International System
under their public policy and determine operational limitations
(SI) units or inch-pound units are to be regarded separately as
for various operations by using the data from this testing in
standard. The values stated in each system are not necessarily
conjunction with the specific concept of operations proposed
exact equivalents; therefore, to ensure conformance with the
by the applicant.
standard,eachsystemshallbeusedindependentlyoftheother,
1.4 The test method provides four methods for evaluating
and values from the two systems shall not be combined.
the potential for impact injury: a simple analytical method, a
1.9 This standard does not purport to address all of the
simplified test, a more rigorous test, and a test method normed
safety concerns, if any, associated with its use. It is the
to approximate energy transfer values with appropriate safety
responsibility of the user of this standard to establish appro-
margins applied to each approach to address uncertainty in
priate safety, health, and environmental practices and deter-
each of the approaches.
mine the applicability of regulatory limitations prior to use.
1.10 This international standard was developed in accor-
1 dance with internationally recognized principles on standard-
This test method is under the jurisdiction of ASTM Committee F38 on
UnmannedAircraftSystemsandisthedirectresponsibilityofSubcommit
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: F3389/F3389M − 20 F3389/F3389M − 21
Standard Test Method for
1
Assessing the Safety of Small Unmanned Aircraft Impacts
This standard is issued under the fixed designation F3389/F3389M; the number immediately following the designation indicates the year
of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval.
A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This test method is applicable to small unmanned aircraft (sUA) that are limited in the United States in accordance with 14
CFR § 107.3 to be less than 55 lbf. The test method provides a standardized method for assessing the safety of sUA impacts with
a person on the ground. Results from testing using Methods A, B, C, or CD are intended to be used to support an applicant in
obtaining permission from the governing Civil Aviation Authority (CAA) for flight over people. Approval of reports for the conduct
of tests and the decision to grant permission rests with the governing CAA based upon adherence to the methodologies outlined
in this test method.
1.2 This test method is based on methods researched by the FAA Center of Excellence for Unmanned Aircraft Systems (UAS)
supported by the Alliance for System Safety of UAS through Research Excellence (ASSURE). These methods expand on extensive
research and testing conducted by the automotive industry to support quantitative automotive passenger safety standards and
testing and test data on sUA collected by ASSURE.
1.3 The purpose of this test method is to define a method to establish confidence in the overall injury potential of a particular sUA
configuration under probable failure conditions. This testing is not meant to simulate the worst possible impact for the most
conservative set of the population. It is expected that CAAs should determine what injury thresholds are acceptable under their
public policy and determine operational limitations for various operations by using the data from this testing in conjunction with
the specific concept of operations proposed by the applicant.
1.4 The test method provides threefour methods for evaluating the potential for impact injury: a simple analytical method, a
simplified test, and a more rigorous test test, and a test method normed to approximate energy transfer values with appropriate
safety margins applied to each approach to address uncertainty in each of the approaches.
1.5 The applicant should understand the actual operating characteristics of their sUA before starting the process outlined in this
test method. It is assumed that the applicant is able to substantiate the most probable, worst case worst-case (MPWC) impact
orientation of the sUA; typical and maximum operating heights and speeds; and terminal velocity of their sUA as a function of
altitude to compare the results of the impact analysis with the proposed operation for the sUA. This test method is intended to
supplement the verification requirements of Specification F3298 and Specification F3322, as well as a supplement to Specification
F2910. This test method should not be used as a stand-alone document without consideration of other ASTM UAS standards.
1.6 These methods assume that a blunt force head impact is the most likely injury mechanism leading to serious injury or fatalities.
The level of blunt force injury to the head may be adjusted for various applications (such as sUA operations around first responders
with helmets) and compared with the amount of force or load factor that the sUA transfers during a collision.
1
This test method is under the jurisdiction of ASTM Committee F38 on Unmanned Aircraft Systems and is the direct responsibility of Subcommittee F38.01 on
Airworthiness.
Current edition approved April 15, 2020Sept. 1, 2021. Published July 2020November 2021. Originally approved in 2020. Last previous edition approved in 2020 as
F3389/F3389M–20. DOI: 10.1520/F3389_F3389M-20.10.1520/F3389_F3389M-21.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
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F3389/F3389M − 21
1.7 Method B is not appropriate for foam-built fixed-wing sUA due to the stiffness of the FAA Hybrid III ATD Head and Neck.
Until a different impactor can be developed for Method B, these sUA should use Method C or D for evaluation.
1.8 Units—The values stated in either International System (SI) units or inch-pound units are to b
...