A Sky Full of Drones

4 March 2020

The Proliferation of Drones and Its Consequences

Recent developments are creating a proliferation of aerial vehicles without pilots onboard, commonly called drones.  As a result, the frameworks for managing airspace are going to need to change in very significant ways.  However, drone technology, and their resulting capabilities, is advancing much more rapidly than the regulatory systems that control their operation.  There will be a number of significant impacts as a consequence.

From Piloted to Unpiloted Aerial Systems

Up until recently, most man-made objects in the skies were controlled by onboard pilots (predominantly fixed-wing airplanes and rotary-wing helicopters, with a few balloons, blimps, paragliders, and other miscellaneous types). Small numbers of hobbyist models, typically radio-controlled by remote pilots, were operated in very localized and constrained airspace areas.

Now there is a veritable explosion of drones of all types and sizes that are sharing airspace with piloted aircraft.  Drones range in size from hobbyist systems weighing a few grams, to high altitude long-endurance surveillance aircraft the size of small airliners.  Even modest-sized drones can have intercontinental range, and some drones using solar power are capable of essentially unlimited endurance.

Drone Air Taxis and Delivery Drones

Several dozen companies around the world are working on electrically-powered vertical takeoff and landing air taxis intended to operate in dense urban environments.  Rather than flying to and from existing heliports with well-established flight patterns, such air taxis are envisioned as operating with minimal locational constraints.  Initially piloted, air taxis are expected to soon operate autonomously under artificial intelligence (AI)t software guidance.

Many other companies are developing drone delivery systems to carry modest-sized packages from a distribution center directly to the consumer’s front yard or doorstep.

Both of these systems will drastically change where air vehicles will be flying, operating in close proximity to people, ground vehicles, and structures.  They will create new hazards, particularly to other aircraft.

Existing Frameworks for Airspace Management

Up until now, management of the airspace has evolved under an implicit set of assumptions.  Larger air vehicles were assumed to be controlled by onboard pilots, or, in a few cases, by pilots controlling them remotely with a highly-capable closed communications link.  Smaller air vehicles, such as model airplanes, were controlled by remote pilots who kept them in line of sight.  Where each category of aircraft was allowed to fly was highly regulated.

An extensive system of air traffic control was developed to manage airspace and guide aircraft to avoid collisions with each other and with objects on the ground.  In controlled airspace, aircraft were required to be in two-way voice radio communication with human air traffic control personnel.  In controlled airspace, aircraft also carried a transponder to aid in radar tracking of their three-dimensional location.  In a recent development, aircraft in U.S. controlled airspace have been required to carry a system that broadcasts their identity and GPS-based 3-D position and track information.  This system is called ADS-B (Automatic Dependent Surveillance-Broadcast).

Drone operations are not being well-coordinated with these airspace management structures.

Existing Systems of Regulation

A very extensive system of regulation has developed over the last century to manage aerial safety.  Aspects include regulation of the design and manufacture of piloted air vehicles; regulation of the software for piloted air vehicles; regulation of the maintenance of piloted air vehicles; regulation of the training and certification of aircrews, maintenance personnel, and air traffic management personnel including recurrent training and recertification, and extensive regulation of the operation of piloted air vehicles in public airspace.

This regulatory structure has not anticipated the introduction of large numbers of drones operated by new categories of operators.

Current Problems with the Regulation of Drones

The existing system of regulation is being seriously challenged by the advent of large numbers of unpiloted air vehicles in the airspace they share with piloted air vehicles.  Key problems include the following:

• There is pushback by operators against the requirement that every drone beyond the smallest size be registered with a government authority.
• Associated with this, there is currently limited control over the transfer of ownership of a drone.
• As a result, drone operators can be anonymous. It may be difficult or impossible to determine who is responsible for operating a drone, particularly if it causes a problem.
• There is no regulation of the design and manufacture of drones. Similarly, there is no regulation of the modification of drones or the maintenance of drones.  As a result, there is no control that assures the airworthiness of drones, similar to the control of airworthiness of piloted air vehicles.
• There is limited regulation of drone operator training and certification, including recurrent training and recertification. Pilots of manned air vehicles, of course, have extensively managed training and certification.
• There is no regulation of the capabilities of drone datalinks, e.g., to prevent jamming.
• There is limited enforcement of rules and response to violation of rules.
• Overall, there is limited international coordination among relevant authorities regarding the policies for drones.

Difficulties Already Being Observed in Drone Operations

Drones are already being observed flying in airspace where they are prohibited, such as in the traffic patterns for airports, over public gatherings, and in airspace where emergency operations are being conducted, such as forest firefighting.  Flight operations in such airspace areas have had to be suspended until the drone threat has been removed.  There is currently no means to ensure that drone operators get NOTAM (Notice to Airmen) type information in a timely manner to identify things such as temporary flight restrictions in an area.

Drones typically don’t reliably show up in air traffic control tracking systems, either with radar skin tracking, transponder responses, or ADS-B broadcasts.  So the air traffic control environment can’t provide guidance to other aircraft to prevent possible collisions with drones or steer drones away from potential hazards.

Except for the largest examples, drones are virtually invisible to other aircraft.   Thus, depending on pilots to see and avoid other aircraft is not practical in the case of drones.  The problem is even worse at night or low visibility conditions, as drones typically do not carry lights and beacons as are required for piloted aircraft.

Minimal Barriers to Becoming a Drone Operator

Hobbyist level small-scale drones can be astoundingly cheap (retailing for less than $20).  Even professional-level drones for aerial camera work are relatively inexpensive.  Furthermore, low-end drones can be extremely easy to use by amateurs.   They require much less skill and training than operating a typical radio controlled model airplane.  So there are low barriers to limit who can become a drone operator.

Drone Software Issues

Currently there is no regulation of software for drones.  However, drone software is critical to drone safety.  Increasingly, drone software will incorporate substantial degrees of artificial intelligence, including machine learning capabilities and self-modification.  The problem is that such software will be non-verifiable, non-certifiable, and non-explainable.  If there is a problem traceable to drone software, it may not be possible to determine either the cause or the needed corrections.

Some drones are being provided with geo-fencing software, endeavoring to define three-dimensional regions of the airspace where they are prohibited from entering (e.g., in the vicinity of airports).  At this time, this is not a requirement for drone operation.

In many cases, drone software will provide fully autonomous operation.  Once programmed with the operator’s intent, the drone will need no further interaction with the operator.  If the drone is not interacting with air traffic management systems, it may not be controllable in real time.

There are no current requirements for drone cybersecurity, to prevent hacking a drone (e.g., taking it over through its control datalink).

Collision Concerns

Delivery drones and autonomous air taxis will need to operate in very close proximity to people, vehicles, and structures on the ground.  The reliability of drone collision sensing and avoidance is questionable, particularly as the number of drones in use expands exponentially.  They can collide with each other as well as with wires, trees, and other fixed and moving objects on the ground such as vehicles.  A collision with any but the very smallest drone can be extremely hazardous to human life.  And, of course, drones create significant collision hazards to other air vehicles.

At this point, there is no mechanism for coordinating drone flight paths among multiple drone operators (both organizations and individuals).  They are basically operating independently.

Privacy Concerns

Drones will inevitably collect high resolution visual information at close proximity to people and objects on the ground in the course of their operation.  This has significant implications for privacy.

Drones in Military and Intelligence Operations

Unmanned air vehicles are proliferating widely in military use.  Armed drones are already in service in several dozen countries, with more being developed and ordered.  Militarized drones are being developed for a vast range of missions.  Many classes of military aircraft are being considered for un-manned or optionally-manned operation to avoid risking human aircrews.

Large swarms of small drones are envisioned for overwhelming the defenses of large systems such as ships, command centers, surveillance radars, and the like by arriving from many directions simultaneously.

Since September 11, 2001, the United States has conducted many hundreds of drone-launched missile strikes against a wide variety of targets, particularly in the Middle East and Central Asia (Afghanistan, Pakistan, Somalia, Yemen, Iraq, and Libya).  The highest profile drone attack was probably the U.S.’s assassination of General Qassem Suleimani, Iran’s top general.  Another high profile drone attack was a failed assassination attempt on President Maduro in Venezuela.  The source of that drone attack has not been reported.  The precedent of drone attacks on top government officials is very concerning.  Are we heading into a world where every high-level public official and every controversial figure will feel at risk for such an attack?

Of course, drones have been used for many decades for intelligence gathering and surveillance operations.  This is only expected to expand in coming years.

Drones in Police Operations

Police forces around the world are adopting drones for a variety of operations, including drones with lethal armament.  The public has had little say in approving of such use.

Intelligent software for drones can include features such as automatic face recognition to identify, locate and follow an individual person autonomously.

Terrorist Use of Drones

Airborne drones pose a serious threat in the hands of non-state terrorists.  An example is the terrorist threat to commercial air travel.  How many airliners would have to be lost through drone collisions for commercial air travel in a region to be essentially shut down?  Drones have already been used by terrorists to damage key facilities such as oil refineries.

Counter-Drone Operations

Trying to counter dangerous drones is challenging because the cost ratio is very unfavorable.  Typically, the counter-drone capabilities (e.g., a laser cannon system) are much more expensive than an individual small drone.  Adding drones can overcome the resources deployed to counter them.

Remotely taking control of an errant drone appears to be difficult, particularly if the drone is functioning autonomously, rather than under remote control by an operator.

Problems in the Regulation of Drone Developments

Rulemaking is inherently a slow process.  The capabilities of drone systems are outstripping the capabilities of regulatory and legal systems to control them.  Because drone development and operation is not limited by national boundaries, rules and standards need to be coordinated internationally to be effective.  Note that drone development will take place in the countries with the least restrictive regulations.  For example, the largest producer by far of small civilian drones is China.