Introduction

Congress is currently debating whether state, local, and tribal governments should have any say in the regulation and governance of recreational and commercial drone activity taking place in and just above their communities. A bipartisan measure, the Drone Federalism Act (DFA),[REF] proposes a cooperative-federalism approach to the regulation of Unmanned Aircraft Systems (UAS).[REF] Below 200 feet in altitude, “the authority of a State, local, or tribal government to issue reasonable restrictions on the time, manner, and place of operation of a civil unmanned aircraft system” would not be automatically preempted by federal law.[REF] Above this altitude,[REF] drones would remain under the control of federal regulators, much as manned aviation is today.

President Donald Trump has also taken action, signing a presidential memorandum ordering the Department of Transportation to establish pilot programs to “promote the safe operation of unmanned aircraft systems” and “continued technological innovation” in this field.[REF] The three-year program aims to test new types of drone operations and study various methods of regulating these operations, with the goal of developing a “sufficiently flexible” regulatory framework that features close “involvement of State, local, and tribal governments.”[REF] As the President has noted, “Input from State, local, tribal, and private-sector stakeholders will be necessary to craft an optimal strategy for national management of UAS operations.” Secretary of Transportation Elaine L. Chao recently wrote that the “pilot program will help ensure that Americans reap the benefits of safe drone technology.”[REF]

Critics of such a framework argue that anything short of total federal preemption will result in a “patchwork” of regulation that will inhibit development of the drone industry and risk the safety of the nation’s airspace. These arguments are wide of the mark. The federalism framework proposed in the DFA and the President’s memorandum recognizes that drones present unique benefits as well as diverse challenges and risks that run the gamut from local concerns such as where, when, and how drones should be permitted to operate in airspace below 200 feet to the inherently federal interest in promoting manned aviation safety.

Consequently, the existing aviation regulatory framework, which places virtually all authority exclusively in the hands of federal regulators, is not well-suited to drones. Only a cooperative-federalism approach that leverages the unique competencies of state, local, and federal officials will allow for the development of a competitive, safe, and innovative drone industry.[REF]

The Aviation Regulatory Framework

Aviation regulation in the United States has long been a primarily federal affair, and for good reason. The market for air travel is without question principally interstate.[REF] Even aircraft that operate exclusively intrastate often fly in the same airspace as long-haul craft bound for distant locales. Operating aircraft in the same airspace under different sets of rules would risk chaos and create significant threats not only to the aircraft themselves, but also to people on the ground. It is therefore natural that a single set of regulations should be developed to ensure that the navigable airspace is used as safely and efficiently as possible.

In the United States, the authority for promulgating these regulations is vested in the Federal Aviation Administration (FAA).[REF] Its authority over aviation is sweeping. The FAA and its predecessor regulatory bodies have imposed all manner of aviation regulations, including pilot training and certification; aircraft design standards and mandatory design review (such as the requirement that manufacturers obtain a type certificate, which certifies that an aircraft design is airworthy); safety standards and requirements; the establishment of flight paths and safe altitudes of flight; and other operational rules[REF] governing everything from aircraft noise to the flow of air traffic.[REF] Taken together, these regulations have preempted virtually the entire field of aviation law and regulation.[REF]

This federal regulatory scheme goes back to the 1926 Air Commerce Act, passed to facilitate the rise of manned aviation in the United States.[REF] The act vested sovereignty over the national airspace solely with the “United States Government.”[REF] The law established the “navigable” airspace—that portion of the air above the “minimum safe altitudes of flight”[REF]—and set it aside as a “public highway” reserved primarily for aviation.[REF]

This decision was driven by practical necessity. The prevailing maxim of airspace property rights at the time, known as the ad coelum doctrine, held that landowners possessed everything above and below their property without limit.[REF] Under this theory of ownership, an aircraft flying at 10,000 feet could be held liable for a trespass each time it crossed a boundary line from one plot of private land to another. The burden of obtaining easements increased as the range of aircraft grew; a single long-haul or transcontinental flight might require thousands of individual agreements with landowners, any one of whom could refuse to grant overflight rights. Under these conditions, aviation development almost certainly would have ground to a halt. Creating the concept of the “navigable airspace” as a federally regulated commons solved the problem by rolling back—but not eliminating—private airspace property rights.

The Supreme Court of the United States endorsed this act in an aviation-related takings case out of North Carolina. In United States v. Causby, the Court held that the old ad coelum “doctrine has no place in the modern world.”[REF]

In the same opinion, however, the Court also concluded that this new “aerial highway” did not extend into “the immediate reaches above the land.”[REF] The Court provided only an ad hoc methodology for identifying the extent of these “immediate reaches,” but its ruling was clear that at least some private property interest remained in the airspace near the ground, regardless of federal aviation law.[REF] The Court wrote that “the meaning of ‘property’…will normally obtain its content by reference to local law.” Citing a North Carolina statute, the Court continued:

Sovereignty in the airspace rests in the State “except where granted to and assumed by the United States.” The flight of aircraft is lawful “unless at such a low altitude as to interfere with the then existing use to which the land or water, or the space over the land or water, is put by the owner”…. Subject to that right of flight, “ownership of the space above the lands and waters of this State is declared to be vested in the several owners of the surface beneath.”[REF]

Thus, the Court could comfortably conclude, based on principles of federalism and common sense, that a “landowner owns at least as much of the space above the ground as he can occupy or use in connection with the land.”[REF] This “use,” incidentally, is not limited to physical construction or occupation; a landowner may “use” unoccupied space “in the same sense that space left between buildings for the purpose of light and air is used.”[REF]

Low-Altitude Drone Activity

It is in this low-altitude airspace, understood in Causby to be private property, that much of the drama related to UAS is currently unfolding. This fact is driven by three principal forces: regulatory limits on drones, technical limits on drones, and demand for particular services.

Regulatory Limits on Drones. Part 107 commercial drone regulations, which were put into effect in 2016 and which govern commercial drone operations in the United States, require drones to remain within 400 feet of the ground or within 400 feet of a structure.[REF] These conditions are unusual in the aviation context, as FAA regulations, for obvious safety reasons, typically require aircraft to avoid flying near the ground or physical structures.[REF] Drones must be flown within visual line of sight of the operator, and a drone must have a physical operator in control at all times.[REF] By design, FAA rules keep drones out of the navigable airspace, near the ground, and no more than several hundred feet from an operator.

Several drone manufacturers have rolled out geofencing technology that limits the maximum vertical altitude at which their drones may operate in accordance with airspace restrictions.[REF] Similarly, the Academy of Model Aeronautics, the nation’s largest hobby flying organization, requires members to abide by a 400-foot ceiling when operating within five miles of an airport.[REF] President Trump’s recent memorandum appears to be designed to pave the way for future federal regulations that will permit drones to operate beyond visual line of sight, operate autonomously or be controlled en masse, and engage in higher-altitude flight.

Technical Limits on Drones. The second condition that holds drones principally to low-altitude airspace is the inherent performance limitation of their design.[REF] Drones are almost exclusively battery-powered, with flight times measured in mere minutes.

Most drones now on the market are rotor-driven quadcopters or octocopters that expend most of their energy generating lift. As a result, these devices are relatively slow. Were they to fly in a linear path, they would likely cover only a few miles before their batteries die. This range would be reduced still further if the drone were to be saddled with a payload like a package or a camera. While larger models, and especially fixed-wing drone models, have greater endurance, all are range-limited by the strength of the control signal generated by the remote used to operate them. It is reasonable to assume that future innovations will overcome these limits and produce drone designs with improved range and carrying capacity, but considerable improvements in battery technology will be needed before small UAS see significant range gains.

Demand for Particular Services. Most scenarios currently envisioned for the use of drones, whether civil, commercial, or recreational, involve drones flying in low-altitude airspace for most or all of their operations. On the recreational side, as noted, there is the 400-foot ceiling established by the Academy of Model Aeronautics. On the commercial side, current uses for drones—aerial photography,[REF] property inspection,[REF] agriculture,[REF] and real estate development,[REF] among others—largely, if not exclusively, involve flights near ground level.

The same holds true for future uses. Even assuming that regulatory and technical hurdles are overcome, drones used for individual package delivery,[REF] aerial light shows,[REF] or infrastructure inspection[REF] will necessarily operate for significant periods of time at low altitudes, including in airspace immediately adjacent to private property or public land, such as a local park. Civil uses, such as supporting law enforcement operations[REF] or search-and-rescue functions,[REF] will take place principally in this envelope of atmosphere as well.

What Will Drone Commerce Look Like?

These three factors, taken together, help to paint a picture of the near future of drone activity.

First, drones will likely conduct significant operations in low-altitude airspace. Under Causby, at least some of the airspace that will be crisscrossed by drones is private property. As long as the public demands drone services that entail flight at very low altitudes, this tendency toward low-altitude flight is likely to persist after the regulatory and technical hurdles holding drones to relatively low altitudes are overcome. In some cases, drones may fly at higher altitudes and drop into this near-Earth envelope of airspace when needed to complete a task, such as delivering a package. In other instances, drones may be used entirely in low-altitude airspace and never venture more than a few hundred feet above the ground.

Second, even as obstacles like communication limitations are overcome, existing battery technology will likely tie drones to a single area with a relatively tight radius. Drones are not likely to be used to ferry packages across tremendous distances—for example, from a warehouse on one side of a state to a recipient home on the other or in a different state altogether. Rather, the drone portion of this equation will represent the “last mile” of a vast logistical network and will operate out of a series of discrete “hubs” that receive packages and serve as home bases for drone fleets.[REF] In such a case, delivery drones would fly no more than a few miles at a time and would seldom venture outside of tightly defined local areas.

Much, if not most, drone activity will take place very near the ground, though high-altitude operations will also take place, assuming that regulatory restrictions on access to the navigable airspace are eventually lifted. Simply put, drones may become ubiquitous, operating in higher-altitude airspace currently reserved for manned aviation, all the way down to the blades of grass in individuals’ back yards: airspace that under Causby, is private property.

Federal Preemption for Drones?

In 2007, the FAA published a policy notice in the Federal Register declaring for the first time that drones were to be considered “aircraft” for the purposes of federal law.[REF] The consequences of this declaration were profound: According to the agency, “[a]s aircraft, these devices generally are subject to FAA oversight and enforcement.”[REF]

FAA officials have since made public statements to the effect that drones have expanded the navigable airspace down to ground level.[REF] In 2015, the agency released a fact sheet asserting that virtually the full field of state drone law and regulation was preempted by federal statute and regulation.[REF] Under this legal interpretation, states and localities would have no independent authority to adopt operational restrictions on drone conduct taking place at any altitude.[REF] Only the FAA could control drone conduct even when that conduct takes place one inch above private land and in no way involves a federal interest.

Broad federal preemption has proven to be both necessary and successful in the context of manned aviation.[REF] Would equally broad federal preemption produce the same socially beneficial results in the context of unmanned aviation? The answer is “no.”

Harms and Risks. It is clear that the uses to which drones will be put are incredibly diverse. So are the potential harms and risks they engender. For example:

• A recreational operator learning to fly his new drone above his backyard risks damaging his neighbor’s property or harming the neighbor himself;
• A drone delivery hub will likely create a significant nuisance for nearby homeowners as drones buzz about;[REF]
• A poorly charted course from a hub to a home could result in a drone invading private airspace and committing an aerial trespass;
• A photographer flying over crowds to capture a local holiday parade might inadvertently collide with a float; and
• A drone hobby club flying dozens of drones in a public park might deter residents from using the park for fear of their safety or simply because they do not like the noise.

In addition, criminals could use drones to smuggle illicit drugs or weapons into a prison, reckless or willfully dangerous operators might create hazards for manned aviation or fly their drones into restricted airspace above federal installations, and poorly constructed drones could fall from the sky, injuring people or property.

Drone activity, simply put, will involve wide-ranging sets of interests. Some fall squarely within the realm of FAA authority and expertise; others fall far outside of these areas.

State and Local Regulatory Authority. In our federal system, the U.S. government is one of limited enumerated powers. By ratifying the Constitution, the states sacrificed some of their innate sovereignty to form the Union, but they retained a broad police power that the federal government lacks.[REF] Courts presume that federal regulations will not preempt a state from exercising its “police” powers unless that is the “clear and manifest purpose of Congress.”[REF] This police power allows states and localities to impose various regulations in the name of protecting and advancing the public health, safety, and welfare.[REF]

It is common knowledge that state and local rules address details of life on the ground. This is no quirk of the system; it is by design. The Framers of the Constitution believed strongly that most decisions that directly affect the people should be made at the level of government that is closest to them.

Regulations promulgated at the non-federal level address a wide variety of issues, including:

• Determining the location, time, and safety of pamphleteering, protest, and other public demonstrations;[REF]
• Regulating commercial activity;[REF]
• Preventing violence, crime, and obstruction of law enforcement officers and first responders;[REF]
• Setting nuisance and navigation ordinances to control for noise,[REF] light,[REF] waste,[REF] and other environmental concerns;[REF]
• Defining property rights[REF] and overseeing land use;[REF] and
• Establishing local traffic patterns, speed limits, and parking rules.[REF]

Many of these areas of expertise and authority are directly related to local drone commerce and recreation. It is doubtful that distant federal regulators will be sufficiently aware of the full and constantly changing picture of particular local conditions that may inhibit, interrupt, or otherwise affect drone activity.[REF] Such knowledge will be necessary for the promulgation and maintenance of any highly particularized operational regulations that may be needed for wide-scale drone commercial activity.[REF] The FAA knows that its staff is at a comparative disadvantage in responding to local concerns.[REF] It is therefore unreasonable to assume that federal regulators will be more attuned to the needs and desires of local residents than are those residents’ own elected officials.

It is equally unlikely, however, that local jurisdictions can match the FAA’s expertise in aviation safety. Given the federal equities at issue and the truly novel nature of drone activity, some degree of federal oversight of this experimental process is clearly warranted. The optimal outcome would therefore be for the FAA to oversee the initial development of local drone rules and in the process help state and local jurisdictions develop the core competencies necessary to regulate the field. Such a process, as the presidential memorandum makes clear, will require a degree of experimentation.[REF] This approach also has bipartisan support in Congress.[REF]

Management and Enforcement. Before a federal court ruled that the FAA recreational drone owners’ registry was unlawful, the number of registered recreational drone owners was fast approaching one million and far exceeded the number of licensed pilots in the United States.[REF] Meanwhile, the FAA issued some 22,959 remote pilot certifications in the first three months that Part 107 was in effect.[REF] By some estimates, the number of drones currently active in the United States is already measured in the millions, and this number will only increase in the coming years. By comparison, according to FAA figures, more than 15,000 air traffic controllers manage 50,000 flights per day, with approximately 5,000 commercial aircraft flying above the U.S. at any one time.[REF] In terms of raw numbers, drones dwarf traditional aviation.

As drones proliferate, so will the enforcement challenges. Simply put, the agency does not have the manpower needed to address drone-related violations of federal aviation law in low-altitude airspace everywhere in the country. The FAA has a total staff of 50,000 employees.[REF] By comparison, there are more than one million full-time state and local law enforcement agency employees, including 750,000 sworn officers with arrest power.[REF]

As aviation innovation continues its rapid advancement—companies are on the verge of bringing supersonic transportation and “flying cars” to market—the already high demand placed on FAA personnel, facilities, and resources will only increase. Thus, the FAA can expect to confront additional challenges to the efficient management and use of the national airspace.[REF]

The FAA recognizes that its “aviation safety inspectors, who are the agency’s principal field elements responsible for following up on…unauthorized and/or unsafe activities, will often be unable to immediately travel to the location of an incident” involving a drone.[REF] With so few resources and so many complex, evolving issues to address, Congress should not let the FAA displace state and local government officials as the primary regulators of crime, tort, and property concerns simply because an incident happens to involve a small drone.[REF]

Toward a Cooperative-Federalism Regulatory Framework

The most common analogy drawn between drones and existing technology is the airplane. This is an attractive comparison because of the fundamental operational similarities between manned and unmanned platforms. Over time, these similarities will become more pronounced for those UAS that develop into high-altitude, long-range aircraft. At the same time, these similarities will likely diminish for systems developed to operate exclusively in low-altitude airspace and across short ranges.[REF] UAS will need more than one regulatory framework to address the disparate externalities that they will engender.

It is therefore useful for the purposes of establishing a framework for this latter category of UAS that recognizes a need for state and local regulatory action to analogize drones to ground transportation. Automobiles do not operate within the confines of a single regulatory regime; overlapping rules and regulations are imposed at all levels of government. For example, automobiles are subject to federal manufacturing and safety standards, as well as federally imposed fuel economy standards; state-issued licenses are required to operate motor vehicles; and vehicles are driven in accordance with traffic laws that are set at the state and local levels. Enforcement of traffic laws is handled principally by state and local law enforcement officers.

Ground transportation thus provides an instructive model for the regulation of drones: a model that is instinctively understood by lawmakers and the population at large and that allows regulations to be imposed at various levels of government in accordance with the principles of federalism and the relative strengths, interests, and expertise of federal, state, and local regulators. Under such a framework:

• The federal government would be empowered to adopt regulations necessary to protect federal interests, such as the safety of manned aviation and the integrity of the navigable airspace, and federal assets, including government property and military installations;
• FAA regulations would govern the flight of drones operating within the navigable airspace or in any other controlled airspace;
• The FAA would be best positioned to set performance and safety standards, such as fail-safe requirements, and impose equipment mandates where needed; and
• The FAA could certify drone designs that are being manufactured for sale in U.S. markets.

Overall, federal officials have unparalleled aviation expertise, and this should be used to help develop, standardize, and harmonize drone rules adopted at the state and local levels.

The federal role in a cooperative-federalism approach to drone regulation is necessarily broad, but significant work remains to be done at the state and local levels.[REF] States and localities, for example, are best positioned to define airspace property rights, to define a cause of action for nuisance or trespass as applied to unmanned drones, and to impose reasonable operational restrictions on drone activity in low-altitude airspace in accordance with the demands and norms of individual communities. Such restrictions could take the form of speed limits, acceptable hours of operation, or limited bans near major local functions such as a parade or a high school football game. Existing land-use authority confers the ability to regulate takeoff and landing operations by drones within communities. States and localities could also prohibit drone interference with ongoing law enforcement activities.

It is important to note that this local and state-level authority would necessarily be restricted to the low-altitude airspace described in Causby. Given that the Court did not precisely define the extent of low-altitude airspace, it would be incumbent on Congress to define the altitude at which state and local authority would end. This altitude should be set high enough to permit a reasonable degree of regulation of local affairs while leaving a sufficient buffer between it and the navigable airspace. Both the Drone Federalism Act and the President’s memorandum set this ceiling at 200 feet.[REF]

A “Patchwork” of Regulation?

A prevalent argument made in favor of broad, aviation-style preemption of the drone industry is the “patchwork” argument. The assertion is a simple one: If states and localities are permitted to impose any regulations whatever, or if property owners retain an interest in superadjacent airspace, the result will be an unworkable “patchwork quilt” of property boundaries and regulations that will hinder the development of the drone industry. This argument held sway a century ago when Congress first federalized aviation regulation. In the drone context, however, it is overblown.

Recall that small UAS are restricted to principally low-altitude, relatively short-range operations. Drone delivery services undoubtedly will be developed in the near future, but present plans for their use in this context involve frequent short-range trips between a local drone hub and homes or businesses within a tight local area. Other operations will involve even shorter flights. For example, a real estate agent using a drone to photograph a new property on the market will not need to fly a drone more than a few hundred feet at any given time, possibly within the bounds of a single property. Thus, drones are likely to operate within the confines of a single jurisdiction or perhaps a small handful of jurisdictions at a time. It is no more unreasonable to expect operators to be aware of local rules governing drone conduct than it is in any other context.[REF]

The information problem contemplated by advocates of the “patchwork” argument—that it will simply be impossible for operators to be aware of the rules in all of the jurisdictions in which they operate—also misses the mark. This problem is hardly unique to drones, and companies like FedEx and UPS have proven that they can maintain awareness of and abide by local traffic laws and regulations while managing thriving businesses.

In fact, dealing with this type of problem is easier than it has ever been. Consider mapping software such as Google Maps or Waze, which permit coast-to-coast travel through dozens or possibly hundreds of municipal jurisdictions. These apps provide turn-by-turn directions, advise drivers of the local speed limit and local incidents such as construction and accidents, analyze traffic patterns in real time and advise when faster alternate routes are available, and even inform drivers as to what lane they ought to use. This technology is helping to make possible fully autonomous vehicles, which will be able to operate on any road in the country without human intervention. All of this is possible without federalization of the nation’s roads and traffic laws.

Similar technology already exists in the drone field. The FAA, for example, has released the B4UFLY mobile app to advise UAS operators of airspace restrictions in effect where they plan to operate.[REF] Major companies, such as the Chinese drone manufacturer DJI, incorporate geofencing services that prevent operation in areas where drones are forbidden. Such technologies could be expanded to incorporate local drone regulations, permitting operators to make themselves aware of and adapt to changes in the regulatory environment easily and quickly.

Not every city and state will necessarily adopt pro-drone rules and regulations, but if operators find particular restrictions to be overly burdensome, they remain free to challenge them or take their business elsewhere. Thus, in addition to the aforementioned benefits that accrue from a cooperative-federalism approach to drone regulation, consumers and entrepreneurs can count on one more: the creation of a competitive environment between cities and states. This will encourage experimentation as governments vie for drone commercial activity. Initially, some degree of variety will likely exist in local and state rules, but this is to be expected in a field as novel and immature as drone technology and should be embraced. Learned experience will separate unsuccessful regulatory regimes from successful ones, and as clear best practices emerge, laws and regulations will converge, much as they have with ground transportation.

This process of standardization should not be rushed, held to arbitrary timetables, or dictated in a centrally planned solution. It is true that there are significant benefits to uniform and predictable regulations, but any gains could be minimized if the resulting regulatory framework is not robust.

Conclusion

The proliferation of drones in the airspace over the United States poses fresh regulatory challenges. Manned aviation and society as a whole benefited greatly from a federally preempted regulatory environment that removed legal, regulatory, and property-rights barriers to the development of that industry.

Simply applying this legal and regulatory scheme to drones, however, will not produce the same socially beneficial outcome. Small UAS are, and will continue to be, operated in a manner vastly different from traditional manned aircraft. Their harms and risks cut across a broad swath of interests from the federal to the local. No single regulatory body is equipped to address all of these issues effectively. Consequently, only a cooperative-federalism model that leverages the expertise of federal, state, and local governments can provide adequate governance of the drone industry.

—Jason Snead is a Policy Analyst in the Edwin Meese III Center for Legal and Judicial Studies, of the Institute for Constitutional Government, at The Heritage Foundation. John-Michael Seibler is a Legal Fellow in the Meese Center.