57TH ANNUAL CONFERENCE, Accra, Ghana, 19-23 March 2018
WP No. 90
Display of Unmanned Aerial System (UAS) Surveillance Data on Controller Working Position
Presented by PLC and TOC
Availability of surveillance data from Unmanned Aerial Systems (UAS), and the potential displaying of that data on controller working positions in current ATM systems raises many issues that may translate into additional responsibilities and liabilities for controllers, and new technological issues that must be overcome. Consideration of all aspects of integration, including consultation with controllers and their representative bodies, must be a priority for Regulators and ANSP’s when proposing changes to regulations, policies, procedures or work practices associated with this technology.
1.1. Remotely Piloted Aircraft Systems (RPAS), Drones, Unmanned Aerial Vehicles (UAV), or as this paper will describe them, Unmanned Aerial Systems (UAS), are all commonly quoted descriptions for a wide range of similar technologies. Generally, what is being described is an airborne craft without a pilot on board, operated or controlled either remotely, or via pre-programmed autonomous flight. Whether they are large (the size of an aeroplane or helicopter), or small (from the size of your palm to something that can carry cameras or a larger payload) they all fall under one of many acronyms or descriptive titles.
1.2. Presently a ‘real-time’ pilot or operator could be within line of sight a short distance away from the craft, using visual line of sight operations (VLOS); or considerably further away using beyond visual line of sight operations (BVLOS), as is the case with current military use and certain certified operators.
1.3. New technologies for controlling and monitoring drone traffic, Unmanned (Aerial Systems) Traffic Management systems (UTM), are being developed and tested by many companies. Integration with current ATM platforms will be the challenge, and where they succeed or fail in being effective.
1.4. Technology is changing at such a rapid pace that tiny ADS-B transmitters, that could fit in the smallest of craft, are already available. Having UAS monitored or controlled by Air Traffic Control would be an understandable, and not unreasonable, request from operators of these systems and also other airspace users; so, the question is not whether we should do this, but whether we can (in a practical and technological sense).
1.5. Potential safety benefits for both RPAS operators and pilots of existing aircraft, with an Air Traffic Controller managing all traffic with separations and/or traffic information, will be most likely be contrasted with the increase in traffic information, and additional restrictions or separation requirements, depending on the airspace category.
2.1 IFATCA policy related to unmanned aircraft is:
|AAS 1.10 OPERATIONAL USE OF UNMANNED AIRCRAFT
IFATCA is opposed to the operations of any autonomous aircraft in nonsegregated airspace.
All Remotely Piloted Aircraft Systems (RPAS) operations in non-segregated airspace must be in full compliance with ICAO requirements. Whether the pilot is on-board or not shall be irrelevant for the purposes of air traffic control, therefore the same division of responsibilities and liabilities as manned aircraft shall apply.
ATCOs shall not be held liable for incidents or accidents resulting from the operations of RPAS that are not in compliance with ICAO requirements, in nonsegregated airspace.
Standardized procedures, training and guidance material shall be provided before integrating RPAS into the Civil Aviation System.
(IFATCA Technical and Professional Manual, 2017 edition, page 3 2 1 14)
2.2 The commercial drone community worldwide is lobbying for more freedom and is looking at new technology that will place drone operators on a par with current airspace users. There is an expectation all users will then receive a similar service with fewer restrictions than they currently have. They are lobbying governments and regulators to legislate change to the current management of airspace, to include them. It is most likely that the primary reason for these actions is not to make the skies safer, but to benefit economically from this new technology.
2.3 Current regulations and procedures segregate, limit, or exclude operations in controlled airspace to keep them clear of published approach procedures, and tightly control or exclude use close to aerodromes and other sensitive areas.
2.4 An industry developed solution, Geo-fencing (where the software of the UAS is programmed in such a way to prevent flights in designated areas based on the GPS location), and other developing technology is available but not mandatory. It also does not address the millions of UAS without it. These features or rules work well for responsible UAS operators, but do not consider, and cannot contain, the operations of rogue flights in these areas where the operator chooses to ignore or doesn’t know the regulations, or deliberately bypasses system safety features.
2.5 As of today, there’s no specific regulation requiring UAS to be equipped with devices for the transmission of identification and position. This makes almost all the UAS flying at low level classified as non-cooperative targets in regards of the present ATS surveillance system. Their shape and size, surrounding terrain, buildings and vegetation compromise their detection from ATS surveillance systems.
2.6 The addition of UAS surveillance data on an ATM screen could both help and hinder a controller’s situational awareness. The visibility of all targets may assist decision making, with some ATM’s able to differentiate categories of targets with color or shape; but it could also be a visual distraction due screen clutter. Increased controller workload from interpreting the screen, will invariably make a controller’s job of separating and segregating traffic more complex and time consuming.
2.7 In a practical sense, whilst surveillance targets are a means of identification and verification on a radar screen; Visual Separation is the primary means of separation in a tower environment. With the size, shape, speed and operating altitudes of UAS making it difficult to see them from a distance, it becomes difficult for a controller to use this separation for sequencing or provision of accurate traffic information, let alone attempt to determine the physical location of a drone from information derived from its radar surveillance data.
2.8 Technological issues arise when considering integration of UAS into ATM’s, such as the 1090 MHz transponder frequency. It would be a limiting factor in busy airspaces where the allocations are already nearing capacity, as was highlighted in 2014 in Europe, where Mode S Transponder frequency saturation resulted in some transponders stopping transmission for several seconds at a time, which then resulted in the aircraft target being lost to radar systems for lengthy periods. (ICAO SP-ASWG6-WP16)
2.9 UAS generally operate at geometric altitude (satellite based GNSS levels, and existing airspace users operate at barometric altitude, so it is imperative that any ATM/UTM systems are able to provide accurate and consistent surveillance data for controllers to use i.e. the same altitude reference for all targets displayed.
2.10 ANSP’s considering integration of UAS, or a UTM, into an ATM system must have appropriate rules and procedures in place before implementation. Consultation with active and current controllers, and their representative organisations should be mandatory. Training for ATC’s in the use of any addition or alteration to an ATM system, work practice or airspace rule must be a requirement. All training must be supported by rules, regulation and policy so that the controller is protected in the same way as in the current system, with no additional liabilities introduced.
If the Human Machine Interface (HMI) is changed at all, in the way we interact with our workstations and displays, when introducing this technology, training should again be mandatory.
Controllers should not be required to fulfil administrative tasks related to UAS flight plan handling, external communications etc. whilst on an operational position where the additional workload may reduce safety or be detrimental to existing airspace users.
2.11 As Regulators and ANSP’s seek to facilitate this new technology, there must be due consideration given to the education and training of all aviation participants, in the development of policy or regulation.
2.12 When inclusion of UAS surveillance data on an ATM becomes viable, in the sense the implementation is appropriately planned and managed at all levels, including meaningful controller and airspace user consultation, all equipment and procedures should meet established aviation standards and criteria.
2.13 Some states have already certified RPAS operations under existing Air Operator Certificates. For example, the Leonardo /HPE Falco project (“Leonardo to provide ‘drones as a service’ surveillance for civil operators” www.leonardocompany.com/en/-/drones-as-service Retrieved: December 2017 ) has UAS flights completing tasks like environmental monitoring, firefighting, humanitarian surveillance, migration flows, emergency response and border control.
2.14 Extra-Large RPAS (conventional aircraft sized from light aircraft to freighters/airliners) should be integrated into the current ATM system far more easily as they will essentially be modeled on existing aircraft but designed to be pilotless and flown remotely or autonomously.
2.15 Upper airspace RPAS, although not very common presently, will operate the same as now, e.g. google loon’s high-altitude balloons, but will get more frequent as more operators use the technology for current task like surveying / terrain mapping, and a myriad of other opportunities these ventures could bring.
2.16 The discussions in this paper may provide guidance for these considerations, although are not meant as an exhaustive list that summarises everything conceivable when investigating integration of UAS into existing airspace and any subsequent displaying of UAS surveillance data on ATM systems. It is more an informed guide that will evolve over time as the technology itself evolves.
3.1. Consideration of the practicality, sensibility, and most importantly, the safety of the system will be required prior to implementation of integration of UAS data into ATM’s.
3.2. Only when the systems are capable of doing so without negatively affecting the primary and existing function of the ATM or the priorities and workload of the controller, IFATCA encourages Regulators, ANSP’s, suppliers and users to consider integration of UAS data into ATM systems.
3.3. Until such time that this is possible, IFATCA believes the current method of allowing UAS use in controlled airspace, by way of segregation from, and in some circumstances exclusion from, areas around aerodromes and other sensitive airspace, is the safest, and most prudent or acceptable method of facilitating this rapidly evolving technology.
3.4. Controllers must be central to, and included in, any planning, design or creation of systems to facilitate the inclusion of surveillance information from UAS on controller working positions or changes to operating practices in relation to this.
3.5. IFATCA recommends ANSP and Regulators include training and education of all airspace users, including Controllers, in the application and use of any regulation, policy and procedure, or equipment changes that may occur as a result of integrating UAS into the existing aviation framework.
4.1 It is recommended that this paper is accepted as information material.
IFATCA Technical and Professional Manual, 2017 Edition.
Potier, E., International Civil Aviation Organization, (16 October 2017). “Sixth meeting of the Aeronautical Surveillance Working Group, Mode S Reply Rate Limiting” ICAO: Montréal, Canada.
www.leonardocompany.com/en/-/drones-as-service Retrieved: December 2017.
Last Update: October 1, 2020