Two decades ago, the notion of arming an uninhabited aerial vehicle (UAV) was little more than a niche pursuit. Today, at least 20 countries have weaponised UAV systems in their inventories, with other nations pursuing acquisition, while the capability is also proliferating to non-state actors. The air vehicles range from small, crude, hobbyist-style UAVs favoured by some non-state groups, to large, long-endurance platforms capable of being fitted with a range of sensors and air-to-surface weapons. Technological development continues apace with an increasing emphasis on greater automation and reducing the human workload, along with the emergence of a type of hybrid UAV and air-to-surface munition along side the more established loitering munition. While uninhabited systems are increasingly embraced by many armed forces, they remain an uneasy subject in the wider public realm, where the perceived lack of human control remains an ethical issue. There also continues to be concern in the legal community regarding how increasingly automated – and perhaps one day autonomous – weapon systems fit within the law of armed conflict – legal concept rather than legislation, sometimes also referred to as international humanitarian law. These subjects were the focus of a 21–22 June 2021 seminar organised by the International Institute for Strategic Studies (IISS) Europe to help further the debate and to better understand the implications of weapons-capable uninhabited systems. This paper reflects the discussions and many of the issues raised by the participants.

While the emergence of the armed UAV is associated in the public mind with the US invasion of Afghanistan in response to al-Qaeda’s 11 September 2001 murderous attacks, work was already underway to provide the MQ-1 Predator with an air-to-surface weapon. The first air-launch of an AGM-114 Hellfire missile from a Predator had taken place on 16 February 2001.1 This, however, was not the first time the US had tested air-launched munitions from a UAV. In the early 1970s the BGM-34 family of what were then known as ‘remotely piloted vehicles’ had been used to experiment with the delivery of weapons. This culminated in the BGM-34C programme that was to fall foul of technical over-ambition and of strategic arms-reduction aims with the Soviet Union. In the case of the former the launch and recovery architecture to support the BGM-34C was ungainly, while in the case of the latter, the 1979 Strategic Arms Limitation Treaty II dealt with the BGM-34C as a cruise missile, rather than a UAV, and would count toward Washington’s ceiling of these systems. Taken together, these put paid to the programme. It was a further 20 years before the US was to revisit putting weapons on a UAV.2 Shortly after the 11 September 2001 attacks, armed Predators were deployed in Afghanistan.3

The introduction of a handful of armed Predators marked the beginning of a far wider adoption of armed UAVs that, as of 2021, has seen the commonplace use of such systems in conflicts. The first chapter of this paper considers the use of armed UAVs in: the short conflict between Armenia and Azerbaijan; the Russian supported fighting in southeast Ukraine; and the civil wars in Libya and Syria. Armed UAVs have played a role in each, though to differing degrees and with varying levels of impact. For several of the actors involved it has provided an operational test environment in which to develop and refine tactics, techniques and procedures and to draw lessons for future developments.

Authors: Douglas Barrie, Niklas Ebert, Oskar Glaese & Franz-Stefan Gady

Date: 21 December 2021