Communicating with UAVs: Unmanned Aerial Vehicles for Emergency Services
By Joetey S. Attariwala
Originally published in the Sept/Oct 2008 issue of 9-1-1 Magazine
The ability of emergency services to effectively and efficiently communicate are complex issues, as we all know; however, these complexities are compounded when the desire to communicate is directed at unmanned systems. Remotely operated vehicles have been used for various tasks by SWAT teams and bomb squads for a number of years, but these systems are quite basic in their function, and have not required high levels of technology. Today, energies are focused at the implementation of Unmanned Aerial Vehicles (UAVs) for domestic emergency service applications.
There are a large number of technical and regulatory hurdles facing this capability, some of which have innovative solutions and are described below.
Commander Sid Heal of the Los Angeles County Sheriff’s Department (LASD) is the officer in charge of that department’s Technology Exploration Unit (TEU), and has acute knowledge of the issues involved with operating unmanned vehicles. A key project the TEU has been working on is the development, test, and evaluation of a UAV to support law enforcement officers and deputies in the field. According to Commander Heal, “All our projects benefit directly from the expertise of the respective subject matter experts during our field trials. When projects become commercially available, we anticipate them looking very similar to our test platforms.” The LASD UAV program is so unique it has garnered international interest from various law enforcement agencies.
The UAV project was initiated in the mid-1990s, primarily to address some of the issues the Sheriff’s Department encountered with helicopter support provided by their Aviation Bureau. “The two biggest problems we experience with helicopters is the noise they produce, which interferes with ground communications for officers, sometimes inhibiting it completely. As a result, we’d often have them (helicopters) go up or go out because we couldn’t hear. The second point is that many times they aren’t available when needed, and we’d commonly have our own deputies compete for helicopter resources,” said Heal.
LASD currently operates a total of 18 aircraft, composed of 15 helicopters and three fixed-wing planes. This is an enviable number of aviation assets to have, however, staffing issues with respect to adequate numbers of pilots and Tactical Flight Officers is a limiting factor for the accessibility of these resources. As a result, the TEU began work on the validation of UAV technology intended to directly support officers in the field. According to Heal, “We’re not setting out to replace helicopters; what we see are two fundamental strategic missions for UAVs. One is to augment the missions of existing helicopters if they aren’t available for whatever reason, and the other would be to actually replace some helicopter missions. The latter is unlikely to occur in LA County as we are blessed with helicopter assets, but it could very well occur in many areas of the country.”
In domestic law enforcement applications UAVs can provide precise and real-time imagery to a ground control operator, who can then disseminate information to other units on the ground, so informed decisions regarding the deployment of officers, for example, can be made quickly. When considering law enforcement applications, many appreciate how a UAV could assist in finding or following a barricaded or fleeing suspect. UAVs are in fact quite versatile as they can map areas, help search for lost children or hikers, and assist in patrolling coast lines, surf lines, harbors, and border regions.
UAVs around the world are composed of many different platforms. These unmanned aircraft are divided into categories that help to describe their size and general purpose. The U.S. Department of Defense defines a UAV as a powered aerial vehicle that does not carry a human operator, uses aerodynamic forces to provide lift, can fly autonomously or be remotely piloted, can be expendable or recoverable, and can carry lethal or non-lethal payloads. The extreme ends to the categories of UAVs range from the large HALE (High Altitude Long Endurance) category exemplified by Northrop Grumman’s Global Hawk, down to the small, mini, and micro UAVs. Until now, UAVs used by law enforcement are either remote control or toy planes that have been enhanced, or are military systems that have been adapted for law enforcement duties. The UAV that LASD is testing is the first platform to be built from the ground up with the intent to be used for domestic law enforcement and other emergency service applications.
Communicating with the Sky
According to Spence Fraser, general manager of Meggitt Defense Systems Canada, a worldwide industry leader in UAVs, unmanned ground vehicles (UGVs), and unmanned water surface vehicles (USVs), “The key things to remember about urban unmanned vehicle performance is multi-path interference – that being the inherent challenges of radio frequency propagation, and what to do when you lose connectivity. For unmanned air vehicles, there are protocols in the command software that engage when you lose link. This can, for example, direct the UAV to return to the last area of decent communications connectivity or commence a recovery sequence. The other essential technical elements to note are the two common types of links that most platforms have, that being a data link and a video link, unless you use a commercial off the shelf Wi-Fi capability. The problem of poor links most often rears its head when operating in or around buildings. If you are a first responder, the way around the problem of operating in a city is to footprint performance, which essentially helps locate areas of interference, at which point you can address these areas to help propagate signals. This of course requires investment and is not normally forecast.”
Communication links required to operate UAVs in urban environments have to be robust to be reliable and safe. Too much power and you wind up with harmonics, which can interfere with data links. Appropriate measures by any agency desiring use of UAVs would be to select an appropriate frequency, making sure it is “clean,” ensuring radios are suitable for the task, testing the platform, and using spectrum analyzers to ensure there are no dirty signals in operating areas. Additionally, encryption becomes an issue if one wishes privacy or security. All of this must be gauged in comparison to cost. A large urban law enforcement agency could afford to operate UAVs after having addressed these issues, but what about smaller ones? UAVs will not have a significant role in law enforcement unless these issues are legitimately overcome.
A non-military domestic use precedent for UAVs has been set by the use of the General Atomics Predator-B, which was used by Customs and Border Patrol in Operation Safeguard, an experimental law enforcement program that conducted observation missions along the U.S.-Mexico border. The Predator-B was designed for military applications, and is a highly effective platform with a long endurance flight time. Unfortunately, limiting factors for the use of the Predator-B or other large UAVs include the necessity of a runway for takeoff and landings, as well as the high cost of the system. This negates the use of large UAVs as quick response tactical assets, or affordable assets for local or even state agencies.
LA County Sheriff’s SkySeer
When exploring domestic law enforcement requirements, deputies quickly decided it was important to investigate a UAV that could be easily carried in a patrol car and is durable, light, quickly deployable, and easy to operate. The mini UAV that LASD is considering is called SkySeer, and is manufactured by Octatron, a subsidiary of Chang Industry Inc. SkySeer weighs less than five pounds, and can be assembled within five minutes. The maximum flight time is 70 minutes, and the aircraft has passed rigorous flight control tests. The antenna fitted to the aircraft is literally a small wire, which is necessary to save weight and reduce drag.
The ground control station for SkySeer fits into a case that is slightly larger than a briefcase, and includes a telescoping antenna. The case lid houses a computer touch screen, and the lower portion of the case is fitted with two joysticks and a keyboard. One joystick serves to control the pan and tilt camera on the platform, while the other joystick is removable with a tether (or can be wireless) to the ground station – and is meant to control the aircraft. External power in the range of 12-36 volts of direct current is needed, and can be provided by any vehicle. “Some of the compromises that were made would not be appealing to the hobbyist or the military, however, they specifically address problems for law enforcement, not least of which is portability – the fact that you can break it down and ‘throw’ it in the trunk is very desirable. One of the big advantages of this UAV is that it would be on-scene and available when needed,” said Heal.
Currently the TEU UAV program is in a proof-of-concept development stage. Depending on how much value a UAV would yield, it is estimated that LASD alone could procure up to 20 UAVs if they become certified and approved for operation. Heal admits that the UAV being considered at the moment is relatively primitive and intentionally doesn’t address all the issues concerning UAV operations. For example, privacy concerns are a moot point, as SkySeer currently doesn’t have the visual acuity necessary for this to be a factor. “We don’t want to fight all the battles facing us all at once,” says Heal.
When considering UAV operations, there are a number of communication, engineering, and regulatory factors that make this a difficult technology to employ. Most mini and micro UAVs require a human controller that is within visual line of site of the platform at all times. This is not a trivial issue because if an operator is required to visually see the UAV, the whole affair is no better than a remote controlled model plane.
The necessity exists for an air-to-ground (A2G) communication link from the UAV, which is typically difficult to setup and keep running. This is usually done by constantly tracking a UAV with a directional antenna or using a satellite communications link. The Sheriff’s Department TEU UAV would use an A2G link in order to send data back, such as video. The communication problem is always an issue in terms of sufficient bandwidth, reliability, and range of datalink/control connectivity.
Sans Operator Assistance
An alternative to pilot-controlled UAVs are autonomous UAVs. This is where UAV technology is truly headed, and indeed already exists in many military platforms. An operator would key in a flight plan and once the UAV is launched, it flies the set course, orbits the area of interest, collects or transmits imagery, and returns. This is not a trivial undertaking as military UAVs have been lost when a gust of wind, inclement weather, or other anomaly pushes or flips the platform over causing a loss of aerodynamic control. These problems are compounded when a UAV is light and prone to winds, as would be found in the hills and along the coastline of Los Angeles County, for example.
Although radar, acoustical, and communication technology exists for Traffic Collision Avoidance Systems (TCAS) as is found on commercial airliners, how would a UAV keep from running into another aircraft, much less know that a collision is imminent? If considering a mini or micro UAV, altitude concerns for hitting other aircraft are lessened, but they are not negated. Due to FAA regulations, UAVs are not permitted to fly in most air spaces. The city of Los Angeles is surrounded by Class B airspace, which is extremely restrictive for safety purposes. These restrictive areas pose additional hurdles to the use of UAVs.
The “payload” capacity of a UAV is an important factor for any operator. The platform has to be large enough to carry a payload that is meaningful, which usually translates into additional size, weight, fuel, engines, and so forth. It may seem that UAVs would be cheaper to operate than a manned aircraft; however, that’s like saying an airplane’s cost is only in its purchase price. Real costs are hidden in other details such as maintenance, pilots/operators, training, insurance, etc. Unit costs of UAVs vary widely depending on the size and capability of the platform, and operating costs are allocated differently from that of manned aircraft. Overall, a UAV will be less expensive to operate than a manned aircraft, but maybe not as cheap as people expect. At the very least, operating costs would encompass the need to maintain a communication link, a pilot/operator on the ground, fuel which is burned (unless an electric motor is used), and the electro-optical/IR payload which has to be managed remotely.
Another factor that a human brings into the loop is situational awareness. Pilots in aircraft are considerably more flexible than UAVs. For example, if a pilot needs to alter his flight path to track a suspect running from a scene, he’ll be able to use his vision along with that of his co-pilot/tactical flight officer to adjust course of flight. In the case of a fleeing suspect for example, if a UAV sensor operator loses the suspect, he/she would have to resort to scanning the area while the UAV or its sensors get back on the suspect or to his last known track, potentially losing the suspect entirely.
Within Civilian Airspace
In addition to the technical issues, regulatory issues also pose hurdles. As stated in a Congressional Research Service report to Congress: How UAVs could be integrated into civilian airspace within the United States is a fundamental question that would need to be addressed by the Federal Aviation Administration (FAA) and the Department of Homeland Security (DHS). Integrating UAVs into civilian airspace so they could operate safely would require not only the creation of regulatory guidelines by the FAA, but also technical developments. Although there are no guidelines or regulations for incorporating UAVs into the National Airspace System (NAS), the FAA has worked closely with government users of UAV technology in developing a certificate of authority (COA) so NAS can be blocked off for exploratory development or operational testing. A primary concern of the FAA is whether UAVs can operate in already crowded airspace. Before UAVs can be introduced into national airspace, the FAA, DHS, and other relevant users will need to address collision-avoidance, communication, and weather avoidance issues.
Octatron has assured the FAA that until fully certified, they will test and operate the SkySeer to the same standards directed towards remote controlled model aircraft, in that they will not operate within three miles of an active airport, and will only operate at or below 400 feet above ground level (AGL). “We’ll be taking baby steps with the certification of SkySeer and its operation,” said Sam de la Torre, a mechanical/aeronautic development engineer for Octatron.
The capabilities and advantages of UAV platforms are well recognized and highly desired. With Commander Heal and the Los Angeles Sheriff’s Department forging the way, the impetus to introduce UAVs into domestic law enforcement and emergency agencies is gaining steam. Communications and regulatory issues are hurdles that will undoubtedly be overcome – in the meantime, UAVs will continue to draw interest and research dollars. Once these hurdles are breached, this new capability will certainly be explored fully in effort to combat crime and terrorism, and to save lives within the United States, North America, and beyond.
Joetey Attariwala is also a writer and photo-journalist for various international defense, aviation, and law enforcement magazines throughout the world. He is a frequent contributor to 9-1-1 Magazine.