The Micro Unmanned Aircraft Systems Aviation Rulemaking Committee Addresses UAS Flight Operations Over People

The Micro Unmanned Aircraft Systems Aviation Rulemaking Committee (“ARC”), ARC Recommendations Final Report (“ARC Final Report”) was submitted to the Federal Aviation Administration (FAA) on April 1, 2016.  The mission of the ARC was to provide recommendations to the FAA Administrator on a regulatory framework for the classification and operation of micro UAS. Specifically, “The ARC was established specifically to address flight operations over people.”  See Footnote 1 of the ARC Final Report.   The ARC,  composed of members representing aviation stakeholders, including the UAS industry and other stakeholders, took their responsibility quite literally, by examining factors that would allow the flight over people without examining much else.  The report seems to focus entirely on risk factors, i.e., the analysis of impact  on people:

-p 5.  “The ARC agreed to establish risk thresholds based on the probability that direct impact with a person on the ground from a UAS would cause an injury that qualifies as level 3 and above on the Abbreviated Injury Scale (AIS)”

-p. 6. “Based on the information received, the ARC agreed that the metric used to quantify an acceptable probability of an AIS level 3 and above injury should be the impact energy of the small UAS, expressed in joules (J)/centimeter² (cm²). For a particular model of small UAS to qualify for operations over people, the manufacturer of that model will therefore have to certify that the product’s impact energy, as measured by a test established by an industry consensus standards body, does not, in the most probable failure modes, exceed a specified threshold. The intent of the test should be to establish the typical or likely impact energy of the most probable failure mode, and not simply the worst case condition.”

Consequently, the four categories of UAS (except for Category 1) are not based on size but on risk factors based on impact energy:

-Category 1 - for this category of UAS, the ARC recommends a maximum risk impact threshold of a 1% chance of AIS level 3 or greater injury, based on kinetic energy transfer at impact. The impact kinetic energy transfer standard and industry consensus standards are more fully explained in the Category 2 discussion. For simplicity, the ARC recommends using a weight-based measure instead of an impact kinetic energy measure for Category 1… The manufacturers will be required to indicate on the retail packaging the actual flying weight, or a statement that the aircraft weight is less than 250 grams. To provide flexibility in the future, the ARC does, however, recommend that the FAA invite industry to create voluntary, non-binding standards for product marking of UAS weighing 250 grams or less to make it clear to users that these UAS meet the requirement to operate over people.

Category 2 - Category 2 prescribes the performance standards and operational restrictions for operations over people that are conducted by unmanned aircraft that weigh more than 250 grams, but still present a 1% or less chance of “serious” injury (AIS level 3 or greater) to a person in the event of impact. The standard to determine whether the UAS meets the risk criteria will be an impact energy threshold based on information presented to the ARC, and calculated by the FAA in J/cm². During its meetings, the ARC was presented with information from Canada and the commercial space industry suggesting that this calculation would result in a value of 12 J/cm2 and that a quadcopter UAS weighing in the range of 4 to 5 pounds would qualify, depending on its design characteristics and operating instructions. The ARC recommends that the FAA calculate this exact impact energy threshold for the proposed flight-over-people rule.

Category 3 - Specifically, the ARC recommends that a small UAS be permitted to conduct limited operations over people (as defined below) if that UAS presents a 30% or lower chance of causing an AIS level 3 or greater injury upon impact with a person. The ARC recommends that the FAA also establish an impact energy threshold for this risk level based on information presented to the ARC, in J/cm².

Category 4 - Category 4 includes operations conducted by UAS operators that present the same risk as UAS conducting Category 3 operations over people, but without Category 3 operational limitations, and therefore require a risk mitigation plan specific to the operation (discussed below in Section 4.3.4). The industry consensus standards for this category are also the same as the standards for Category 3, but with the addition of the risk mitigation plan, which may include coordination with the FAA or event sponsor, municipality or local law enforcement, and pilot training, experience and certification commensurate with the increased risk, as determined by an industry consensus standard.

In addition to safety of persons on the ground, the recommended addition of engagement with appropriate third parties is intended to address concerns about the social acceptance of operating a UAS over large gatherings or events. It is the ARC’s recommendation that this facilitation of local engagement, while not intended as a delegation of jurisdiction over UAS operations, will be helpful to address community concerns.

I added the emphasis because this language establishes  that  a significant part of the Category 4 operations will be coordination with local law enforcement.  The FAA has been recommending this for some time, as the agency does not have the resources to police all UAS infractions themselves.  See  Law Enforcement Guidance For Suspected Unauthorized UAS Operations, January 8, 2015, here (“While the FAA retains the responsibility for enforcing Federal Aviation Regulations, including those applicable to the use of UAS, the agency also recognizes that state and local Law Enforcement Agencies (LEAs) are often in the best position to deter, detect, immediately investigate, and, as appropriate, pursue enforcement actions to stop unauthorized or unsafe UAS operations.”) 

The report leaves the development of industry standards to the future, in which industry stakeholders should have the opportunity to participate.  The final form of H.R. 636, the Federal Aviation Administration Reauthorization Act of 2016 will dictate the methods by which those standards will be developed.