If we want to see the benefits of drones, or Unmanned Aircraft Systems (UAS), we need smart regulations that allow the industry to grow while maintaining safety. But if we only define one set of rules for the entire spectrum of unmanned aircraft based on the most dangerous of all activities, we will stifle our ability to use and benefit from the technology and create a high and expensive barrier to entry that reduces competition and innovation.
How can regulators choose what restrictions should be placed on whom?
The solution must involve a tiered regulation system for UAS based on factors of risk. Here are some of the key risk factors the users of UAS need lawmakers to address:
Size and Weight
First and foremost, the most obvious difference between a large, heavy UAS like a Predator drone and a small, lightweight UAS such as a DJI Phantom or Blade Nano quadcopter, is size and weight. The damage that would be caused by a very large versus a very small mass falling from the sky would be completely different.
Regulators have already set one precedent of distinguishing between the two by borrowing from earlier guidelines used for model makers in the 1980’s, which used 55 pounds (25kg) as the general maximum for small RC aircraft. Today the FAA calls these “small UAS”, or sUAS.
However simply dividing between all UAS either below or above the 55 pound mark leaves the users of lighter aircraft at a disadvantage. A large portion of the sUAS that users would like to put to useful purposes weigh between 2 and 5 pounds. The popular DJI Phantom, for instance, weighs around 2.5 pounds. Putting them in the same category as a gas-powered, 40-pound ScanEagle just doesn’t make sense from a risk perspective.
Then, of course, there are also the growing number of palm-sized “nano” UAS being developed and sold. As technology advances these tiny systems will become more capable of offering productive and beneficial uses. Will a device that weighs a few ounces or 100 grams pose the same risk as one weighing 2 pounds? Probably not, which is why as technology moves forward we could see more need for an even smaller category.
Altitude and Airspace
Another very simple differentiation that must be made is between UAS that will fly at higher altitudes where there could be manned aircraft operating, and those to be flown outside navigable airspace such as relatively low to the ground. In fact, the second group encompasses the large majority of the sUAS operations that are currently in demand to benefit users. As with the informal 55 pound limit some refer to, a general maximum ceiling of 400 feet Above Ground Level (AGL) is commonly acknowledged by many to apply to sUAS.
A 400’ AGL ceiling can greatly reduce the risk of a collision, as most manned aircraft fly more than 1000 feet AGL after take off and before landing, but even at 400 feet and below UAS can still pose a risk, particularly to helicopters or in close proximity to airports. Therefore there are different risks based not only on altitude, but also on the use of the airspace.
The National Airspace System (NAS) over the US is broken into various parts over different areas and at different altitudes, and its regulation for manned aircraft involves many factors including aircraft equipment, air traffic control communication, and airport operations. These established rules already tell us where certain types of aircraft may operate, and help us to identify the risks that UAS operating below them may face. UAS that do not need to operate in or near busy or controlled airspace may not require the same restrictions and requirements as those that do, which might for example necessitate the use of transponders, sense-and-avoid technology, or pre-flight approval for the operation and a public Notice to Airmen (NOTAM) to ensure the safety of manned aircraft.
Location and Environment
Most of the proposed new commercial uses for UAS involve operations in places specific to their missions, such as to gather images or data of a particular subject or to deliver or retrieve cargo at a particular location. These locations can greatly influence the risks involved when operating there. Primarily, operating in a place where people or property are nearby increases the risk that a flight emergency could result in injury or damage. Generally, populated areas will involve greater risks than unpopulated areas.
Also, the nature of the location can pose a variety of special risks, such as dynamic changes including moving hazards, inaccessibility or obstructions, or weather factors such as visibility, precipitation, and wind. Operations at night, over water, near moving objects, or around obstacles are all entirely possible to achieve safely and successfully, however they may involve more risks and therefore may merit different requirements. Operations without these challenges may not require some of the same preparations or precautions.
The objective of a specific UAS operation is another factor in determining the risks that must be addressed. A grid-pattern survey flight may not encounter the same difficulties or pose the same hazards as a flight involving the dropping, placing, or retrieval of cargo, the pursuit of another object, or close proximity to or interaction with a person. Depending on the mission, the risks posed can be different and, again, indicate the need for more or less preparation and precautions.
Command and Control – Autonomy
Finally, we must prepare for current and future differences we will face as we develop and implement new forms of aircraft Command and Control (C2). Each of these methods of controlling an unmanned aircraft has its own unique characteristics of risk.
Single-Operator, Line of Sight – Many small or micro UAS operations can be completed in this way with relatively inexpensive equipment, however it still requires a high, if not higher, degree of operator proficiency than multi-operator flight.
Multi-Operator, Line of Sight – Such as when one operator controls the flight of the aircraft, a second operator controls the payload system such as a camera, and third operator acts as a safety pilot (currently in practice by some companies operating under section 333 exemption). Not only does this require a high degree of training for each member of the crew, but also it requires that a team have skills in how they work together and communicate.
Single-Operator, Beyond Line of Sight – Sometimes referred to as First Person View (FPV) flight, this is a special skill requiring planning, practice, and specialized equipment. FPV missions can certainly be completed safely and successfully, but do involve different challenges and risks. (Presently, BLOS/FPV is not approved by the FAA for multirotor-type aircraft.)
Multi-Operator, Beyond Line of Sight – Very large or high-altitude UAS may be operated in this manner, requiring a very high degree of training as well as coordinated “cockpit resource management” and communication skills to control an unmanned aircraft system as a team without visual reference.
Monitored Ground Station (Auto-Pilot) – Using further degrees of auto-pilot technology, an operator can simply indicate instructions, such as “maintain this position” or “fly this flight path”. As such, the skill level required of the operator and the risks of human error are reduced. The operator essentially becomes a Safety Pilot when not giving instructions.
Unmonitored Ground Station (Pilotless) – When auto-pilot technology is expanded even further, an entire flight operation may be pre-programmed into an aircraft. Doing so further reduces the skill requirements for the operator and the risk of human error during the flight. With the implementation of sense-and-avoid technology and automatic take off and landing abilities, the operation essentially becomes pilotless.
No Ground Station (Autonomous) – A fully autonomous UAS would need only to be given an objective, such as “deliver this cargo to this location”, “find this missing person”, or “make a map of this area”, and it would be able to complete its mission through programming without further direction. When this technology arrives and starts to become widely used, we will again face a different set of challenges, risks, and responsibilities that our regulations will need to address.
The Need for a Risk-Based Regulatory Solution
All of these factors will influence the level of risk involved in UAS operations, and all of them should help determine what regulatory requirements and restrictions are put in place, and when they apply. This would, in fact, greatly simplify the task of authorities to design and enforce safe rules, as it does not require special exemptions for certain activities.
Just as manned aircraft industries already provide for, a tiered structure of regulations for UAS allows for the maximum benefit to users while maintaining strict safety requirements for those aircraft and activities that need them. Therefore the best way to give everyone a fair chance to operate together, keep regulations simple, and maintain the highest priority on safety is to ensure that when regulations are introduced in the United States, they are designed based on RISK.