Module 4 - UAS in the NAS (ASCI 530)

Unmanned Aerial Systems Integrated Into National Airspace System

(Hampton, 2014)

          Under the current Federal Aviation Administration, or FAA, rules all manned aircraft are required to be able to visually identify other aircraft in the airspace whenever weather conditions permit. Furthermore, even aircraft operating under instrument flight rules must be able to look out for other aircraft as they maneuver around the airspace (Hobbs, 2010, p. 521). However, for unmanned aircraft, this is a problem. As such, the FAA has determined that UAS must be able to prove they have a satisfactory level of technology top match a “sense & avoid” capability in manned aircraft. However, the issues with integrating UAS into the NAS are not solely limited to sense and avoid issues. According to a FAA report on the “Progress and Challenges in Integrating Unmanned Aircraft Systems into the National Airspace System,” there are three barriers preventing the FAA from fully integrating UAS into the NAS today. The barriers are a lack of mature detect-and-avoid technology to avoid collisions, a lack of adequate control and communications technology, and lastly a lack of regulatory requirements or standards for UAS design certification, pilot and crew qualifications, ground control stations, and command and   control reliability (Hampton, 2014, p. 4). To further complicate this issue, the three barriers mentioned by the FAA are different depending on the type/size of the UAS.
          Unmanned aircraft are typically categorized into five distinct categories based on weight. Furthermore, each category of UAS has a specific role in which they are utilized. Category 1 (micro) and category 2 (small) unmanned aircraft are more commonly used in low altitude areas and typically outside of controlled airspace (Hobbs, 2010, p. 521). As long as the category 1 and category 2 aircraft are flown in visual range, the pilot, who is still external of the aircraft, can adequately see-and-avoid other aircraft. The issue for category 1 and category 2 aircraft arises when the aircraft is beyond visual range. Australia has attempted to solve this problem for category 1 and category 2 aircraft by putting restrictions on the locations and maximum altitude these aircraft can operate (Hobbs, p. 522). As for category 3, category 4 and category 5, these aircraft operate at higher altitudes and will move between non-controlled and controlled airspace. Additionally, these aircraft will typically operate under instrument flight rules. Due to the fact that these aircraft are generally operated beyond visual range, there may be communication delays or issues between the response of the pilot and the action taken by the aircraft. In an effort to find a solution, there has been chatter about integrating the technology to make these aircraft visible to air traffic control through a transponder (Hobbs, 2010). However, this technology was designed to aid detect-and-avoid not replace it. So the question is… is there current or developing technology that can aid in the integration of unmanned platforms into the NAS?
          The short answer is yes. Currently, NASA and the FAA are working on the “NextGen” of Air Traffic Control. The new system is a patent-pending command and control system capable of providing pilots, crew and other personnel collision warnings and real-time air traffic and weather information (Squires & Epperson, 2016). Lastly, this technology has already been tested in the NAS using NASA’s fleet of Predator B or Ikhana aircraft (Squires & Epperson). The benefit to this system is that it not only integrates UAS into the NAS, it also greatly enhances the capabilities of manned aircraft operating in the NAS.
          The rapid pace in which UAS is being employed is dramatically changing the air domain. As the true capability and benefits to unmanned aircraft are realized, the rules, regulations, and technology holding UAS back must evolve. This is where the NAS is right now. UAS is on the cusp of the next big evolutionary breakthrough but is hampered by the barriers to its integration into the NAS. Hopefully, with NASA and the FAA aggressively working on solutions, the future of UAS will be able to reach its full potential. 
          The aggressive reemergence of unmanned aerial systems, or UAS, has dramatically altered the air domain. One major area in the process of being altered is the integration of unmanned aircraft into the national airspace system or NAS. As it stands right now, integrating unmanned aircraft into the NAS is much more difficult than it sounds. To truly understand the issues behind integrating unmanned platforms into the NAS, three aspects of the issue must be looked at. First, what are the major issues with integrating UAS into the NAS. Secondly, what considerations must be taken for the various types/sizes of UAS. Lastly, is there current or developing technology that can aid in the integration of unmanned platforms into the NAS. As with any problem understanding that there is a problem is the first step in reaching a solution.
 

Module 2 - Weeding Out a Solution (ASCI 530)

Yamaha RMax helicopter Fertilizing Crop

(Curry, 2013)

          The Agro-Hawk company is currently developing a UAS platform for precision crop-dusting. However, the design of the UAS is currently halted due to weight issues. Unfortunately, the Payload delivery team and the Guidance, Navigation & Control (GNC) team each have their particular systems beyond the original weight budget they were allowed. This is due to the team’s efforts to save costs by utilizing off-the-shelf hardware/software to complete their portions of the UAS project. As the lead Systems Engineer, it is crucial at times to ensure a design project not only stays on task but achieves the most if not all of the desired results. Despite this, however, the Systems Engineer must consider added cost and the potential for further delays when attempting to rectify the weight issue. With that said in order to carry the sufficient amount of fertilizer the weight of the two subsystems must be reduced. In order to help both teams reach their particular weight goals, each team will be visited and assisted individually. Due to the customer’s high interest in the payload delivery systems, this is the area that will be assisted first.
          In the current economic state of the country, being able to correctly spray fertilizer over a specified area is of high importance to customers. Especially in hard to reach and hazardous farming areas such as Napa valley, it is imperative that no fertilizer is wasted. Therefore, the payload delivery team must ensure the fertilizer is adequately dispersed across the required area. However, in the interest of saving weight perhaps the payload delivery team can look at the way the fertilizer is dispensed. For the most part, most crops are sprayed using a spray applicator system. These systems are capable of spraying territory at different speeds, which in turn, defines the rate and size of an area the platform can spray. Therefore, if the Payload team were to look at a lower speed spray applicator system, perhaps weight can be saved from having a less powerful motor. In fact, the University of California at Davis is currently experimenting with a crop dusting platform which sprays at 15 mph (Szondy, 2013). This change in motor size or motor capability should be enough to reduce the weight of the payload delivery system back down to acceptable weight. While the weight savings for the Payload team may be significant, it is the GCS team that may have the potential to save the most weight.
          Especially in an unmanned aerial platform, it is imperative that the vehicle is able to fly correctly. However, when the systems required to fly the aircraft correctly prevent the aircraft from flying correctly there is a problem. With regards to controlling the aircraft, there are many options available to the team. One consideration is the removal of the onboard computers and relying on a pilot within line-of-sight of the aircraft. Unfortunately, this process may raise costs due to the acquisition of a qualified individual to operate the vehicle. A better feasible solution is to alter the guidance and navigation method of the aircraft. Typically, agriculture machines are guided and navigated by GPS receivers. These machines often include computers which can correct for the lack of a third satellite lock (you need three GPS satellites for accurate navigation). However, if navigation by GPS is replaced by perimeter fences for electronic positioning, this will not only increase the accuracy of the guidance and navigation but significantly reduce the required equipment (Austin, 2010, p. 274).
          In summary, it will be crucial to have both teams achieve the common goal of reducing the weight of their subsystems. The UAS that Agro-Hawk is developing will ensure farmland is adequately fertilized while keeping pilots away from terrain difficult to maneuver in as well as hazardous locations. The implementation of this UAS has the potential to greatly alter the future of crop dusting and agriculture as a whole.

Module 1 - History of UAS (ASCI 530)

          In the beginning, unmanned aerial systems (UAS) were designed to be target vehicles for training manned aircraft pilots and anti-aircraft gunners. Utilizing the relatively new application of radio transmission, these vehicles were expendable aircraft, typically air launched and recovered via a parachute. However, as time went on in the design and use of these systems, operators realized they may be able to use these “target drones” to solve current aviation problems with intelligence, surveillance, and reconnaissance, or ISR.
          The first aircraft to be put to use in this manner was the AQM-34 Firebee in 1962 (Taylor, 2016). First designed in 1951, this modified target drone was used in a variety of operations which included photographic reconnaissance, electronic intelligence gathering, and radio communications monitoring (U.S. Air Force, 2015). The AQM-34 Firebee was launched from a modified C-130 and could fly a preprogrammed course or be manually flown by a pilot on the ground within line-of-sight. Considering this was an unmanned aircraft, this vehicle was capable of achieving remarkable subsonic speeds and operating at altitudes as high as 75,000 feet (U.S. Air Force, 2015). These capabilities were vital during the Vietnam War and over North Korea during the Korean War. Due to its small radar cross section, the AQM-34 Firebee was able to fly deep into severely defended territory and bring back clear images and even video (Taylor, 2016). Furthermore, at one point in the late 1960s, the AQM-34 Firebee was upgraded with sensors to detect electronic countermeasures in order to determine appropriate missile jamming techniques. Despite conducting more than 3,400 missions the AQM-34 Firebee could not reach its full potential due to limitations in technology. Issues such as a reliable radio uplink and downlink, as well as, issues with large single spectrum cameras would prevent the aircraft from developing further. It would take another 40 years before technology would catch up to the full vision of an unmanned ISR platform.

          In 1995, the intent of the AQM-34 Firebee was reimaged in the form of the RQ-4 Global Hawk. Maintaining many of the same design elements, the RQ-4 Global Hawk’s high altitude operation, as high as 65,000 feet, and small size keeps the aircraft fairly safe from surface-based defensive systems (U.S. Air Force, 2014). However, in the attempt to achieve the full potential of the UAS, the RQ-4 Global Hawk incorporated the new technology of integrated multispectral sensors, high-bandwidth satellite uplink and downlinks, and GPS receivers (Croft, 2005). The introduction of satellite communication links and GPS receivers allow operators much more freedom in locations where the aircraft can be controlled from, as well as, increasing the relative range in which the UAS can operate. Additionally, the RQ-4 Global Hawk learned from previous generations of UAS operations and incorporated a “crew” design to the operation of the UAS. The operation of the RQ-4 Global Hawk is broken into various crew positions, with the most innovative being the position of sensor operator. This position provides the capability to task/retask the sensor, update the collection plan in real time, initiate sensor calibration and monitor sensor status (Taylor, 2016). The incorporation of this position has not only dramatically changed how the UAS is operated it has radically altered the tactics in which the unmanned ISR platform can be utilized.

          The future of unmanned ISR looks promising. The capabilities of the technology have evolved greatly since the days of the Cold War. However, there is a long way to go before unmanned ISR platforms have reached the limit of their design. Currently, in most unmanned aircraft the issues faced are rooted in human factor issues. One such area is the notion that unmanned aircraft must be “flown.”  According to Kevin Williams in his 2004 Civil Aerospace Medical Institute report, unmanned aircraft of today are not “flown” through the air… they are “commanded” (Williams, 2006). The future of unmanned ISR aircraft, such as the RQ-4 Global Hawk, will rely more on a mindset change than continued upgrades to technology.