Summary

As part of a larger effort to determine IFATCA’s position on UAS and the ongoing developments in that field, TOC conducted a policy review of AAS 1.10. Simultaneously, PLC has produced material on UAS as well. Several amendments to IFATCA policy are suggested in this paper, based on the abovementioned developments.

Introduction

1.1. In recent years, IFATCA has produced several working papers about Unmanned Aircraft Systems (UAS). These papers resulted in several policy statements that have been consolidated into one section of IFATCA’s Technical and Professional Manual (TPM). Due to the quickly evolving landscape and utilisation of UAS, it was deemed necessary to perform a review of the current policies and provide updates to the existing material.

1.2. UAS are being bought and flown in record numbers, data shows that by March 4, 2023 there were almost 900,000 UAS registered in the United States. At the time of writing this paper, no data was published about the number of registered UAS in the EU, but the European Union Aviation Safety Agency (EASA) does list the requirement to register UAS with the relevant National Aviation Authority.

1.3. More commercial operators are looking at implementing UAS in their everyday operations. For example, Amazon has ambitious plans to operate a fleet of delivery UAS, offering 30-minute delivery to certain areas. Their first demonstration of the service was Dec 7, 2016 in England. It was rolled out in 2022 in two towns in the United States, where it claims to deliver packages to customers within 60 minutes.

1.4. Most countries have implemented new rules regarding UAS, usually dealing with segregation of UAS and Conventional Piloted Aircraft (CPA). Efforts are underway to integrate UAS more fully in the existing ATM system. Various international bodies and agencies (Eurocontrol, Federal Aviation Administration – FAA, European Aviation Safety Agency – EASA, Joint Authorities for Rulemaking on Unmanned Systems – JARUS, ICAO, among others) are working on concepts such as U-Space and Unmanned aircraft system Traffic Management (UTM), to allow UAS users to interface more easily with the current framework.

1.5. Commercial parties may seek to deploy more sophisticated and capable UAS in their operations. One can imagine situations where these UAS want to enter controlled airspace and current rules and regulations are not fit for purpose. The UAS in question may be required to be outfitted with aviation grade navigation and communication capabilities.

1.6 If UAS were equipped with aviation transponders, there might be issues regarding frequency spectrum congestion on the 1090 MHz and 978 MHz bands.

Discussion

2.1 Different terms are in use when it comes to unmanned aerial vehicles. The most popular and well-known of these is ‘drone’. Strictly speaking, this term refers to unmanned aircraft used in a military context.

2.1.1 Remotely Piloted Aircraft Systems (RPAS) is a term currently in use in many international bodies and environments. It is a subset of the broader Unmanned Aircraft Systems (UAS) indicating UAS that are certified and oversighted according to the same standard as manned aviation.

2.1.2 Unmanned Aircraft Systems (UAS) is the overarching term for all types of airborne systems that are unmanned.

UAS is defined as: an aircraft and its associated elements which are operated with no pilot on board.

UAS can vary greatly in shape, size and performance. RPAS is the commonly used term in IFATCA, but it does not cover the entirety of the spectrum of unmanned aircraft. The term UAS covers all unmanned aircraft and is in wide use in North America and the United Kingdom, as well as European Union legislation.

2.1.3 DOC 10019 Manual on Remotely Piloted Aircraft Systems defines RPAS as follows:

ICAO DOC 10019 Manual on Remotely Piloted Aircraft Systems, First Edition, Montréal 2015.

2.1.4 These definitions differ only on one point and that is that UAS might be controlled in other ways than directly by a remote pilot. Autonomous aircraft for example, may operate according to predefined mission parameters and would be expected to execute their mission while also dealing autonomously with any unexpected or emergency situation which might occur. Skybrary also defines automatic aircraft. These would operate according to predefined instructions, but are not capable of deviating from those instructions without human intervention.

2.1.5 DOC 10019 also mentions the following:

ICAO DOC 10019 Manual on Remotely Piloted Aircraft Systems, First Edition, Montréal 2015.

ICAO appears to adopt a narrower view of RPAS here than the definition in the document would suggest. One interpretation is that we should only consider UAS that wish to integrate into the civil aviation system as RPAS. The EU on the other hand does not mention the term RPAS once in its regulations 2019/945 and 2019/947, pertaining to UAS. EASA has included the term RPAS in its guidance material referenced earlier. At the time of writing, there is no consensus on this issue and therefore IFATCA will include the definitions of RPAS and UAS listed under 2.1.3 in the Definitions section of the Technical and Professional Manual, as both terms are in use.

2.1.6 Although both terms are in use, it is suggested that the term RPAS is replaced in IFATCA policy statements by UAS, as it does not cover all variations of unmanned aircraft (UA). UAS does cover all UA and is therefore a more accurate term.

2.2 EU regulations 2019/945 and 2019/947 set out rules and procedures for UAS manufacturers and UAS pilots respectively. They constitute the most comprehensive effort so far by lawmakers, to regulate the operations of UAS and their integration into the legal and aviation systems. These regulations have been transformed into an extensive FAQ and guidance material resource.

2.2.1 Currently, most countries have implemented new rules regarding operation of UAS and keeping them segregated from CPA. One example, for instance, is allowing them to operate at a maximum of 400 ft AGL and outside 3 NM of airports and outside 1 NM of heliports. However, operators of autonomous UAS may wish to fly in controlled airspace, and these rules do not cover all situations where UAS and aircraft may be using the same airspace. IFATCA is monitoring the development of the UAS industry and more material is expected to be prepared for subsequent conferences (see paragraph 2.8).

2.3 If UAS are to enter controlled airspace as it currently exists, or if CPA are going to be sharing airspace with UAS, it must be ensured that these UAS can operate safely and without inhibiting CPA in their regular operations. Current rules do not provide an adequate framework for this concept of operations in most places.

2.4. ICAO’s ATMOPS panel has devised a rough classification of UAS in three categories:

1) Large UAS that can comply with existing ICAO regulations regarding equipage: Navigational and communication equipment are on board and they participate in the ATM system as any other CPA would. This is the class of UAS that is adequately covered by existing IFATCA policy.

2) Smaller commercially operated UAS: They cannot comply with existing regulations but can be trusted to conduct themselves according to a given ruleset. These might also be operated by the more knowledgeable enthusiast. These kinds of operations are likely to take place with some sort of authorization by the ANSP, whether through UTM or other means. And whether that be tactical on a case-by-case basis or more generally with corridors or “drone zones”. It is not out of the question that the preferable solution is that these operations are kept outside the controller’s situational awareness for screen clutter or workload related issues.

3) Smaller UAS operated by malicious actors or members of the public lacking sufficient knowledge to assess the impact of their activities properly: Procedures and systems to mitigate the hazards for commercial traffic and handholds for controllers to be able to act in these inevitable occurrences are necessary.

2.5 ICAO has developed a resource pertaining to UAS referred to as the Model UAS Regulations. They describe it as, “ICAO reviewed the existing UAS regulations of many States to identify commonalities and best practices that would be consistent with the ICAO aviation framework and that could be implemented by a broad range of States.” This resource breaks down the rules by the respective regulations the UAS operates under. Also, easily accessible from this site are the applicable ICAO Advisory Circulars and links to the Regulations.

2.6 In order to keep controllers involved when it comes to the administration and regulation of the airspace in which they work, it is necessary for IFATCA to continually review and develop policy according to the evolving realities in aviation, to provide controllers with as much guidance as possible. At the end of the discussion section, the current IFATCA policy is reviewed.

2.7 UAS navigational capabilities need to be assessed to ensure that they meet the requirements for the airspace where they will be flown.

2.8 If UAS were equipped with a mode-C transponder or a low power ADS-B squitter, it would aid air crews in being able to spot or at least detect the UAS via electronic means (TCAS) and enable ATC to track the UAS. However, this may cause a nuisance when it comes to scope clutter on flight decks as well as Controller Working Positions (CWP). This also brings up an issue with frequency congestion, as there have already been reports of 1090 MHz bandwidth congestion at busier airports.

2.9 IFATCA’s Technical and Operations Committee (TOC), alongside the Professional and Legal Committee (PLC), is collaborating on several UAS related working papers. For IFATCA’s 62nd Annual Conference in Jamaica, there will be topics presented alongside this paper including UAS Assumptions and High Altitude Operations. In the long term, there will be additional topics that will be explored including UAS Airspace Classification and others for forthcoming Annual Conferences.

2.10 Starting from the 1st of January 2024, all UAS in the European Union weighing more than 250 grams will be required to carry remote identification devices. These will transmit a unique registration number and the device’s location continuously via the mobile telecommunications network. While this is not ready for immediate integration into most current ATM systems, it will allow for more comprehensive trackability and traceability in case of airspace infringements. A UTM system might be able to use this location information for geofencing, notifications or alerting services, as well as conflict detection with CPA.

2.11 UA pilots are currently required to maintain visual line of sight (VLOS), However, most UAS can provide telemetry data to the control base station and some even provide live video. This allows these aircraft to operate beyond visual line of sight (BVLOS). Unfortunately, BVLOS operations have led to incidents where UAS have either inadvertently or intentionally operated in controlled airspace and caused over 1800 sightings of UAS by aircrew in the US (2016). An aircraft moving at 160 knots on approach only has about 8 seconds to respond to the drone. According to the FAA11 , a pilot requires on average 12.5 seconds to see an obstacle, recognize it, be aware of the collision course and make the necessary avoidance manoeuvre.

2.12 With the current practice of see and avoid, UAS will be required to be able to detect other aircraft and UAS and to take appropriate action to avoid collision. It has been suggested to term this concept “detect and avoid”. This requirement may not be possible for all types of unmanned aircraft. This is especially evident in the smaller categories of UAS, as they operate under the principle of line of sight and are unlikely to be equipped with technology of that kind. The implications of this new concept will be investigated further by TOC in the coming period.

2.13 It seems that it is becoming impossible to not allow unmanned aircraft to integrate into the civil aviation airspace. At the same time, air traffic controllers are always very aware of the potential hazards that such a change might bring. Designated areas for UAS to conduct operations within areas like control zones (CTRs), such as corridors or low level “drone zones”, might allow ANSPs to accommodate these operations. Of course, these areas would function to safeguard the approach and final approach areas, as well as the physical manoeuvring area of the aerodrome and the climb out areas. Controllers should be central to and included in any planning, design or creation of areas to facilitate the inclusion of UAS in controlled airspace.

2.14 There are currently a number of simultaneous initiatives active which seek to regulate UAS flights, as well as assess the risks and accommodate airspace users. JARUS is one such initiative, in which some large players in aviation are involved.

2.15 One of the most complex questions, when it comes to the operations of UAS in or near controlled airspace, is the question of what separation standard to apply. In some low-level controlled environments, ANSPs are implementing a concept of integrated and segregated areas. In the segregated areas, UAS can operate at will, with the understanding that they must remain clear of the integrated areas. Should they wish to enter the integrated area, they require approval from ATC as normal. This allows UAS operators more freedom, while at the same time safeguarding CPA.

2.16 Drone operators should be properly qualified according to local and/or national rules and regulations, to operate in controlled airspace. They should also have an acceptable means for immediate communication (VHF, mobile phone/satellite phone) for direct contact with ATCOs or a delegated coordinator for the ANSP.

2.17 Review of Policy

In this section, the policy listed in the IFATCA Technical & Professional Manual (TPM) under section AAS 1.10 is reviewed step-by-step:

2.17.1

This section of the policy remains correct. The definition of autonomous operations means that these aircraft will not be controlled remotely by either an operator or be able to receive instructions from ATS units. This makes their operation incompatible with the definition of controlled, non-segregated airspace. Until a new framework for these operations to be conducted safely is established, this section of the policy should remain in the TPM unamended.

2.17.2

It is questionable if this position is realistic. It means that devices with vastly different performance profiles, navigational and communications capabilities must all be in two-way radio communication in controlled airspace, where controllers are then required to maintain the same separation standards as between conventional aircraft. This concept is only properly applicable with the same sort of performance profile, navigational, communications and surveillance capabilities of all other aircraft operating in the airspace.

ICAO regulations do not exist specifically for UAS. Several efforts are underway to fill this procedural ‘vacuum’ by different initiatives. JARUS is one such initiative. JARUS is a collection of CAAs and other agencies sharing experience and knowledge in order to create a greater understanding of UAS operations and needs, as well as requirements for their safe deployment. IFATCA has been monitoring developments in this group. While there are good developments, there have also been some issues in JARUS’ approach to UAS operations within controlled airspace. It is therefore imperative that IFATCA carefully considers its position in this complex playing field.

If local authorities, using an established Safety Management System (SMS) and with sufficient input from operational controllers, design procedures that allow for safe UAS operations within controlled airspace, IFATCA sees no grounds to oppose accommodating these new users of controlled airspace. Of course, this is a delicate balance to strike, because IFATCA must keep controllers’ interests at heart at all times. High standards from regulators must be expected and critical questions should be asked about how things will remain manageable, both in terms of complexity and workload, as well as safety.

The addition of “non-segregated airspace” is surplus to requirements. It is illogical to imply that it’s not a requirement to be in compliance with the rules in segregated environments. For example, EASA prescribes very specific requirements for drone operators to adhere to, even when operating in designated model zones.

To continue on with the effort to harmonise IFATCA’s policies using ICAO terminology, ‘must’ will be replaced with ‘shall’.

It is proposed that the policy statement listed under 2.16.2. be replaced with the following:

All Unmanned Aerial Systems (UAS) operations shall be in full compliance with established ICAO and/or national and/or local regulations.

This section will subsequently be moved to a different place in the policy statement. This will become clear in section 4 under the Draft Recommendations.

2.17.3

With the growing number of UA operations and the increasing demand for them, it is expected that traffic numbers for this kind of operation will continue to grow for the foreseeable future. If that is the case, these operations and the requirements placed on them by this policy would cause undue workload to controllers and undue restrictions to the burgeoning UAS sector.

From the classification listed under paragraph 2.3 of this document, we may derive policy that is more fit for purpose. When it comes to the larger UAS which are properly equipped, an ability to adhere to current ICAO regulations should be expected. In this case, the above policy is valid and a reasonable position to take.

For the smaller classes of drones, it is not realistic to expect the same division of responsibilities and liabilities, as they will not in all cases have the equipment, training or capability to do such. Different solutions such as segregated areas for UA would be a more practical proposition.

It was pointed out that the wording of the policy was unnecessarily descriptive. Therefore it was decided to maintain the spirit of the policy, but modify the wording to make it more concise and clear.

The suggested new wording can be seen below:

For the purposes of air traffic control, the same division of responsibilities and liabilities shall apply to manned and unmanned aircraft.

In conclusion, the statement can remain, but requires the addition of the risk-based procedures section under 2.16.5.

2.17.4

While this section of the policy is worthwhile because of its protective attitude to ATCOs, it is already a reality that local authorities are devising their own regulations due to the lack of ICAO SARPs. The policy therefore will not cover all situations an ATCO might find themselves working.

For this reason, a rewording of this policy is proposed to reflect the developing situation and clarify that there may be situations where rules have been prescribed by the local CAA, or other relevant authorities. It is also proposed that RPAS is replaced with UAS in this particular section, as it covers all instances of unmanned aircraft.

Further, it is proposed to remove the qualifier ‘in non-segregated airspace’. The reasoning for this is that it is irrelevant where the operations take place. In case an operator is in violation of regulations, ATCOs should never be liable for any incident caused by such a violation.

Replacement proposal:

ATCOs shall not be held liable for incidents or accidents resulting from the operations of UAS that are not in compliance with ICAO and/or national and/or local regulations.

2.17.5 As was raised at ICAO’s 40th Triennial Assembly in Montreal, there is growing concern amongst pilots as well as controllers, about unauthorised drones operating near aircraft in critical phases of flight, at very low level near aerodromes. Incidents like those at London, Gatwick and Dublin, illustrate that the danger of this type of occurrence is real and the economic and potential safety impacts are tremendous. IFATCA recognizes the need for superior guidance for controllers and pilots.

Therefore, it is proposed to add a new policy statement to AAS 1.10:

IFATCA recommends the development of risk-based procedures for UAS operations regardless of whether the operation is authorized or not.

With this policy statement IFATCA states its desire to provide controllers and other aviation professionals the guidance they need, to safely operate in an airspace where UAS operations are a reality. This policy statement will be in addition to the policy which is already in place. A re-ordering of the policy is proposed for clarity reasons.

2.17.6 The rest of the current policy remains valid and should therefore remain in place. The only change in content that is proposed is to change RPAS to UAS, to maintain internal consistency. One final change is made for clarity, as the question was asked what airspace the policy refers to. For that reason it is recommended to make reference to “controlled airspace” in the policy. As mentioned before, it is also proposed to change the ordering of the statements.

The current order of the rest of the policy is as follows:

It is proposed to re-order the policy and change RPAS to UAS and add reference to controlled airspace:

Standardized procedures, training and guidance material shall be provided before integrating UAS into the Civil Aviation System.

IFATCA recommends the development of risk-based procedures for UAS operations regardless of whether the operation is authorized or not.

Contingency procedures and controller training shall be provided for the management of infringements into controlled airspace by Unmanned Aircraft.

IFATCA urges the development and implementation of technology to prevent infringements into controlled airspace by Unmanned Aircraft.

IFATCA encourages education and awareness campaigns on the use of UAS for the general public.

In this way, all policy statements pertaining to procedures are grouped, which makes for clearer reading.

2.18 PLC’s UAS Assumptions paper also discusses some edits to AAS 1.10. The policy statements drafted in that document will be incorporated into these edits, while preserving the integrity and logic of the policy.

Conclusions

3.1 Rather than thinking of all unmanned aircraft as one and the same, it is important to consider the multitude of different types that exist. Unmanned aircraft can have vastly different performance profiles, as well as large variations in communications, navigational and surveillance capabilities. There is no one size fits all approach to regulation, when it comes to UAS. ICAO’s ATM Ops Panel has devised a rough classification of drones, which is very useful for categorising and solution orientation.

3.2 The European Union meanwhile has created a detailed system for classifying UAS and the operations that may be performed with them. This approach has a risk-based outlook, which takes into account the physical properties of the UAS, the electronic capabilities of the system as well as the skill level of the operator.

3.3 The landscape of aviation is changing quickly and sometimes outside the ATC sphere of influence. Rather than reflexively opposing these innovations out of a safety motivated perspective, IFATCA must attempt to remain influential. If controllers want some control over the implementation of new concepts and procedures for UAS, then IFATCA must take a collaborative approach.

3.4 Firm requirements are necessary to safeguard CPA operations, but there are modes available in which both sectors can co-exist and operate side-by-side. Various configurations like Aerodrome Traffic Zones (ATZ), Special Rules Zones (SRZ) or segregated areas are already evidence of this. These frameworks leave the ATM system in charge of what is possible and what is not and is the current preferred concept of operations. Controllers should be central to, and included in, any planning, design or creation of areas to facilitate the inclusion of UAS in controlled airspace.

3.5 Full integration does not seem possible yet, especially when it comes to the smaller, less advanced classes of unmanned aircraft. But the future may bring tools such as UTM, which may allow controllers more influence in UA flight profiles.

3.6 A policy review was conducted to update IFATCA’s position for the developments in unmanned aviation.

3.7 A variety of tools and workarounds are starting to be available to accommodate UAS operations in or near controlled airspace and could provide handholds for ATCOs and CAAs alike, to mitigate the safety risks of UAS operations. Further development of these tools and procedures appears to be the best way forward to achieve that goal. IFATCA has produced work on this before, which continues to remain valid.

3.8 Special care must be taken to ensure that the high pressure from UAS operators and local regulators does not result in a situation that is unsafe for CPA.

3.9 ATC’s foremost priority must always be the safety of conventionally piloted aircraft. That being said, IFATCA acknowledges that collaboration and development of new procedures and standards are necessary, to ensure that UAS integrate safely into the aviation landscape.

Recommendations

4.1 It is recommended that IFATCA policy AAS 1.10:

Is amended to read:

IFATCA is opposed to the operations of any autonomous aircraft in non-segregated airspace.

All UAS operations shall be in full compliance with ICAO and/or national and/or local regulations.

For the purposes of air traffic control, the same division of responsibilities and liabilities shall apply to manned and unmanned aircraft.

ATCOs shall not be held liable for incidents or accidents resulting from the operations of UAS that are not in compliance with ICAO and/or national and/or local regulations.

Standardized procedures, training and guidance material shall be provided before integrating UAS into the Civil Aviation System.

IFATCA recommends the development of risk-based procedures for UAS operations regardless of whether the operation is authorized or not.

Contingency procedures and controller training shall be provided for the management of infringements into controlled airspace by Unmanned Aircraft.

IFATCA urges the development and implementation of technology to prevent infringements into controlled airspace by Unmanned Aircraft.

IFATCA encourages education and awareness campaigns on the use of UAS for the general public.

And is inserted in the IFATCA Technical and Professional Manual.

References

EU regulations 2019/945 and 2019/947.

https://www.faa.gov/uas, March 2023.

“Amazon begins drone deliveries in California and Texas” https://arstechnica.com/gadgets/2022/12/amazon-begins-drone-deliveries-in-california-and-texas/, December 2022.

https://www.easa.europa.eu/en/the-agency/faqs/drones-uas, March 2023.

https://www.easa.europa.eu/en/document-library/easy-access-rules/online-publications/easy-access-rules-unmanned-aircraft-systems, September 2022 Revision.

Review of Radio Frequency Spectrum Protection Policy, WP 88, IFATCA 58th Annual Conference 2019, Conchal, Costa Rica.

Display of Unmanned Aerial System (UAS) surveillance data on Controller working position, WP 90, IFATCA 57th Annual Conference 2018, Accra, Ghana.

FAA Advisory Circular 90-48E, https://www.faa.gov/regulations_policies/advisory_circulars/index.cfm/go/document.information/documentID/1041368, 20th of November 2022.

IFALPA Press Release “Global Pilots & Industry Partners call for New Guidance on Drone Operations” dated 10th of October 2019, Montreal.

FAA Fact Sheet Unmanned Aircraft Systems, March 2015.

ICAO DOC 10019 Manual on Remotely Piloted Aircraft Systems, First Edition, Montréal 2015.

Skybrary: Unmanned Aerial Systems, https://www.skybrary.aero/index.php/Unmanned_Aerial_Systems_(UAS), Last update unknown, last visited 5th of March 2023.

“Dublin Airport Suspends Flights For Third Day In A Row Because Of Drone” https://simpleflying.com/dublin-airport-suspends-flights-three-days-drone/, February 7th 2023.

ICAO Model UAS Regulations, June 2020, https://www.icao.int/safety/UA/Pages/ICAO-Model-UAS-Regulations.aspx.

“South of the Clouds: A roadmap to the next generation of uncrewed aviation”, A. Fuller (NATS Corporate and External Affairs Manager), R. Porter (NATS Head of UTM Stakeholder Engagement and BVLOS Operations Forum Chair).