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Bio-inspired intelligence based control for Unmanned Combat Air Vehicles: Its Challenges

About the author:

Aman Bahl is a 3rd Year B.A. LL.B.(Hons.) Student at Maharashtra National Law University, Nagpur.

Introduction to UCAV

Unmanned combat aerial vehicle (“UCAV”), popularly known as a combat drone, is generally referred to as an unmanned aircraft characterised with military capabilities.[1] It is characterised by its ability to use modern information technologies to manoeuvre itself as well as identify targets, making it an intelligent vehicle which is prepared for performing dangerous and repetitive tasks in remote and lethal environments.[2] Since earlier times, UCAVs have proven to be of significant assistance to society in both military and civilian applications. These vehicles were initially engaged in only civilian fields such as networking, meteorology, disaster monitoring, agriculture, geology, and transportation. Nonetheless, with technological advancements and advance machine learning, they have gained wider military application in contemporary times for advanced fields such as intelligent monitoring and surveillance, artificial interference, military communications, air defence suppression, fighter or cruise missile defence, air-to-air combat and border patrolling.[3]

These autonomous vehicles comprise of technologically complicated components which strongly rely on inter-dependence and coordination among its various components. They essentially comprise of “systems of systems” which provide them with the ability to perform complex calculations and thereby take decisions as per their programming. This enables them to forecast danger and safeguard themselves.[4] There are five attributes that make these autonomous vehicles so distinctive, which are lightweight, low-cost, zero-casualty, high mobility, and unusual ability. However, these attributes may only be partially responsible for steering toward its ever increasing popularity and usage. It is the potential reduction in procurement and life cycle costs, and its capability to persist on task for long periods have brought them to light. It has been studied that human endurance in a fighter jet can be for a maximum duration of ten hours. UCAVs do not face any such limitation as they are autonomous and thus, do not exhaust the pilot or operator.[5]

Artificial brain based high-level autonomous control for UCAV

The term ‘bio-inspired intelligence system’ refers to the concept wherein the motherboard in a machine is designed to replicate the impulses stimulated by the human brain to introduce the ability of cognition.[6] This concept is primarily based on the pre-memory capacity of a human mind which facilitates it to learn continuously. Once this hardware is combined with an artificial intelligence based software, it gets the ability to adopt two chief functions: control and learning. Thereafter, this intelligent device can perform three convolute functions: it acts as an intelligent controller, it uses/activates a sense-based feedback measuring device and becomes an organ-based intelligent actuator. Its ability to systematically use its hardware and software to simulate the behaviour of a real human brain helps it in making instantaneous decisions which ultimately makes it an intelligent controller. Sensors based on proximity and infrared cameras attached on it provides the ability to sense the surroundings, creating a sense based feedback measuring device, and lastly, its ability to synchronize its complex hardware components to simulate the effects of human or animal organs produces an organ-based intelligent actuator. These three attributes together create an advance device which has in turn opened a new array of possibilities.[7]

However, its operations are not free from hurdles. There are two categories of challenges that are typically faced with their operation, i.e. technological and legal challenges.

Technological Challenges:

The purpose behind the development of UCAVs is to perform difficult military operations. While operating deep into adversary territory, the likelihood that constraints in the communication bandwidth may not allow for full-time two-way communications between the control centre and the UCAV is very probable. In such situations, the UCAVs is expected to carry out an effective autonomous operation with the goal of achieving the commander’s intent. The United States Air Force in its ‘Unmanned Aircraft Systems Flight Plan 2009–2047’, has ostensibly supported this concept and stated its firm belief that advances in computing speeds will alter the Observe-Orient-Decide-Action (OODA) Loop and in turn increase the autonomy of the vehicle.[8]

As of today, the biggest difficulty being faced is the lack of a metric by which autonomy levels can be measured. In its absence it is difficult to define if an operation is successful. Autonomy cannot be evaluated in quantitative terms, its needs thorough technical basis which takes into account many factors such as task complexity, human interaction and environmental challenges. The National Aeronautics and Space Administration (NASA) in the United States and the Defence, Science and Technology Laboratory (DSTL) in the United Kingdom have both distinguished operational autonomy into multiple levels. NASA has expounded its own metric value called ‘FLOAAT’ or Function-specific Level of Autonomy and Automation Tool. According to this, six levels of control are offered: wherein Level 0, has no computer autonomy, herein the pilot has full authority and control; Level 1 introduces computer assistance to the pilot when requested; Level 2 uses the computer to offer advice, but the pilot needs to accept it; Level 3 uses computing to conduct tasks, with the pilot accepting or rejecting the recommendations; in Level 4 the computer conducts all tasks, unless revoked, and Level 5 is fully automatic, with monitoring only. Similarly DSTL has defined its own levels.[9]

Referring to both NASA and DSTL, it can be concluded the minimum criteria for autonomy level for an UCAV is Level 3. This level of autonomy allows the UCAVs to Find, Fix, Target, Track, Engage and Assess their targets. The use of Automatic Target Detection (ATD), Automatic Target Initiation (ATI) and Automatic Target Recognition (ATR) technologies will enable faster, efficient and sophisticated military operations. More advanced computer with greater computing abilities along with accurate sensors would create a detailed, cohesive picture of the battlespace which would make these advanced vehicles further more effective.[10]

Legal Challenges:

The twenty-first century has already seen a number of technological advancements; within the cloud of these developments is the introduction of UCAV. However, these modern weapons of warfare need to comply with the principles of international law. Questions such as fixing of liability often arise with use of these autonomous weapons. The Rules of Engagement require humans in the command chain as the minimum requirement in the warzone. This leads to two essential questions: first, whether the decisions made by an autonomous device fall within the definition of ‘command chain’ and, second, whether the weapon has the ability to differentiate between an innocent and a wrongdoer.[11]

The Law of Armed Combat (“LOAC”), also known as Customary International Humanitarian Law needs to be referred to answer the above questions. LOAC is derived from two main sources of international law – treaty law and customary law. It enables states to maintain relations between themselves by regulating the rights and duties of the belligerents in time of armed conflict. There are two fundaments of the LOAC, namely, proportionality and distinction.[12] Autonomous weapons need to operate within the ambit of these fundamental principles. Whenever a weapon is procured by a State, it must ensure that the above principles are kept in mind. Software engineers of UCAV are not exhibited from the prisoner- of-war protections as they are not categorised as lawful combatants. Combatants and Prisoner of War Status, under Rule 106 provides that civilian personnel who are illegal combatants are not provided with the immunity of lawful combatants.[13]

The LOAC already allows for the use of autonomous UCAVs within the constraints adumbrated. Ultimately, individual states are responsible for ensuring that weapon developments adhere to Article 36 of the 1977 AP1 to the Geneva Convention of 1949. Article 36 requires each State Party to ensure that the use of any new weapons, means or methods of warfare that it studies, develops, acquires or adopts comply with the LOAC. In general, once a system has been released into service, legal responsibility will always remain with the person who issued the command to the UAS.

The goals laid down by the International Civil Aviation Organization (ICAO),[14] the 2015 Manual on Remotely Piloted Aircraft Systems (RPAS Manual)[15] and Annex 2 Appendix 4 of the Chicago Convention[16] as assisted by the UAS ‘drone’ Toolkit lay foundations in international aviation law. The Chicago Convention as laid down by ICAO regulates drones aviation. Article 8, Annex 2 Appendix 4 along with pilot licensing form the key legislation in this regard.

Article 8 states:

“No aircraft capable of being flown without a pilot shall be flown without a pilot over the territory of a contracting State without special authorization by that State and in accordance with the terms of such authorization. Each contracting State undertakes to ensure that the flight of such aircraft without a pilot in regions open to civil aircraft shall be so controlled as to obviate danger to civil aircraft”.

It interprets the term ‘flown without a pilot’ to mean an aircraft without a pilot on board thus including the term within its definition. Similarly, the Advisory Circular 2011 states:

An Unmanned Aerial Vehicle (UAV) is a pilotless aircraft, in the sense of Article 8 of the Convention, which is flown without a pilot-in-command on-board and is either remotely and fully controlled from another place (ground, another aircraft, space) or programmed and fully autonomous. This understanding of UAVs was endorsed by the 35th Session of the ICAO Assembly.

The RPAS Manual 2015 and Annex 2 define a ‘Remotely Piloted Aircraft’ (RPA) as ‘an unmanned aircraft which is piloted from a remote pilot station’.[17] Thus, the concept of unmanned combat air vehicles as aircraft being piloted remotely can be concluded from these definitions. However, there are three important aspects of these UCAVs, firstly the UCAV and the data connection and control device is considered as a single entity. Secondly, ICAO has the authority to set minimum standards for the safety of all civilian drones in the States territory. Lastly, ICAO requires the pilot of an aircraft to have final authority of the disposition of that aircraft whilst he is in command in accordance with the rules of the air. Annex 2 does not specify that the pilot must be ‘on board’, therefore even without Appendix 4 remote pilots are covered under Annex 2. The Annex makes clear drones are to be piloted to ‘minimize hazards to persons, property or other aircraft’ in accordance with drone specific safety guidelines of Appendix 4.


In order to understand the legality of the use of UCAV, it is important to consider that the use of force in international conflict is prohibited and the only exemption against such a use of force under the jus cogens principles of self-defence under customary international law. The use of UCAV and thereby target killing constitutes an act of war and the use of force can only be justified as self-defence in an actual armed conflict. The International Court of Justice condemns the attacking non-state actors in hot pursuit in the host states. UCAV’s can however be used against insurgent groups or terrorist organizations by a foreign state with the consent of the host state, but, even then, only to stabilize the region. Hence, drone attacks against the will of a host state or attacks against a state to help rebel groups destabilize a region are entirely illegitimate.[19]

Furthermore, even if the drone strikes are legal, do not constitute an act of war against any state, and are conducted with the consent of host states, they must follow certain humanitarian law principles.[20] Such principles present vigorous restraints over such use of force. First, drone strikes must be undertaken out of absolute military necessity—that is, where recourse to drone attacks or the use of force must be the last available resort to reconcile an armed conflict. Second, to commence a kill list in drone attacks, targets must be combatants—distinguished from the non-combatant civilian population in accordance with the principle of distinction under humanitarian law—to avoid lawlessness and complete injustice. Third, drone attacks must be aligned with the principle of proportionality, by which civilians are protected against collateral damage.[21]

It is rightly said by Anderson and Waxman that “The law, to be sure, makes no requirement that sides limit themselves to the weapons available to the other side; weapons superiority is perfectly lawful and indeed assumed as part of military necessity”. Certainly there is no legal requirement for war to be fair.[22]


[1] Glade, David, Unmanned Aerial Vehicles: Implications for Military Operations, Defence Technical Information Centre, Online:, last visited on 11th October, 2018.

[2] Hashim, Ahmed S., and Grégoire Patte. “‘What Is That Buzz?’ The Rise of Drone Warfare.” Counter Terrorist Trends and Analyses, vol. 4, no. 9, 2012, p. 8–13.

[3] Colin Wills, Unmanned Combat Air Systems in Future Warfare Gaining Control of the Air, 37 (Palgrave Macmillan, 2015).

[4] Marcus, Anthony Allen, et al. “Droning on: The Rise of the Machines.” Dialectical Anthropology, vol. 36, no. 1/2, 2012, pp. 1–5.

[5] Ryan Becker, SCU Aerial Robotics Team- Experimentation with an Autonomous UAV Observation Platform, Online:, last visited on 12 Oct, 2018.

[6]Duan, H., Shao, S., Su, B. “New development thoughts on the bio-inspired intelligence based control for unmanned combat aerial vehicle”44 Sci. China Technol. Sci. (2010)

[7] Ibid.

[8] The “OODA Loop” is a decision-making process originally developed by the military. It consists of four stages that repeatedly performed: observe, orient, decide, and act.

[9] Supra no. 3.

[10] Ibid.

[11] Supra no. 3.

[12] 1977 Additional Protocol 1 (AP1) to the Geneva Convention of 1949, Article 48 of AP1.

[13] Fowler, Mike. “The Strategy of Drone Warfare.” Journal of Strategic Security, vol. 7, no. 4, 2014, pp. 108–119.

[14] Advisory Circular 328 of 2011.

[15] Manual on Remotely. Piloted Aircraft Systems, International Civil Aviation Organisation, Doc 10019 AN/507.

[16] Chicago Convention on International Civil Aviation, (1994) 15 U.N.T.S. 295.

[17] Annex 2, supra no. 14.

[18] Supra note 16, Annex 2 ‘Rules of the Air’ – Appendix 4 – Remotely Piloted Aircraft Systems.

[19] Ashley, Steven. “Robotic Bombers.” Scientific American, vol. 284, no. 6, 2001, pp. 24–24.

[20] Fowler, Mike. “The Strategy of Drone Warfare.” Journal of Strategic Security, vol. 7, no. 4, 2014, pp. 108–119.

[21] Leys, Nathan. “Autonomous Weapon Systems and International Crises.” Strategic Studies Quarterly, vol. 12, no. 1, 2018, pp. 48–73.

[22] Kreps, Sarah, and Micah Zenko. “The Next Drone Wars: Preparing for Proliferation.” Foreign Affairs, vol. 93, no. 2, 2014, pp. 68–79.



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