Weapons Law Encyclopedia

Armed Unmanned Aerial Vehicles

Drones have become a key military tool in warfare and have gained considerable attention in recent years. The most well known drones are the MQ-1 Predator and the MQ-9 Reaper drones. Most people assume Unmanned Aerial Vehicles (UAVs) are a new concept but they have actually been around for decades. 

One of the first times UAVs were used was by the Austrian Army in 1869 when two hundred pilotless balloons were attached with bombs against the city of Venice. R. Naughton, ‘Remote Piloted Aerial Vehicles: An Anthology’, Monash University, 2010.  UAVs have come a long way since then and are only becoming more complex and more lethal.

The founding father of unmanned vehicles was Nikola Tesla. On 8 November 1898, Tesla was the first to patent a remote control for unmanned vehicles. This patent became one of the primary reasons drones exist today. R. Naughton, ‘Remote Piloted Aerial Vehicles: An Anthology’, Monash University, 2010.

Modern Drones emerged shortly after WW1 with the 'the US Navy’s flying bomb, a propeller-driven Curtis biplane.' G. Alley-Young, 'Drone (Unmanned Aerial Vehicle)', Salem Press Encyclopaedia, 2015. During WW2, the US Navy started using UAVs although they weren’t completely effective. 'In World War II, the US Navy’s Operation Anvil used remote-controlled B-24 bombers to bomb German and French targets, though many crashed or prematurely exploded.' G. Alley-Young, Drone (Unmanned Aerial Vehicle), Salem Press Encyclopaedia, 2015.

After the Vietnam War the US military allocated a great deal of money to be spent on UAVs. It started when the Air Force used 'small experimental drones called Fireflies' A. Callam, ‘Drone Wars: Armed Unmanned Aerial Vehicles’,  XVIII International Affairs Review 3 (2010). used for reconnaissance over Southeast Asia. When the experimental drone budget was more expensive than the Pentagon originally planned for, the program was suspended.

When the Israeli Air Force used a weaponized drone, 'the Pioneer', in the 1982 war in Lebanon, the US once again became interested in drones. 'Impressed with the Pioneer, the Navy purchased several and the Reagan Administration began increasing procurement and research in 1987'. A. Callam, ‘Drone Wars: Armed Unmanned Aerial Vehicles’,  XVIII International Affairs Review 3 (2010).

The terrorist attacks on 11 September 2001 changed and accelerated the use of drones in a historic way. The terrorist attacks that day suddenly created a new demand for Hellfire-equipped Predators to hunt down terrorists in remote areas of Afghanistan and Pakistan. During the first year of use the US Air Force hit approximately 115 targets in Afghanistan. These drones continued to be used to target al-Qaeda operatives in other remote parts of the Mideast including Yemen.

'On February 4, 2002, the CIA first used an unmanned Predator Drone in Paktia, Afghanistan, in an attempt to assassinate Osama Bin Laden. When the United States first went into Afghanistan in 2003, it had a few unarmed drones (none on the ground), but by 2013 it had 8,000 aloft and more than 12,000 on the ground.' A. Callam, ‘Drone Wars: Armed Unmanned Aerial Vehicles’,  XVIII International Affairs Review 3 (2010).

At first, drones were mainly used for surveillance but they have now become a critical player in the war on terror and the United States is not the only nation using them. 

According to the LA Times, 'The United States and Britain fly U.S.-made armed MQ-1 Predators or MQ-9 Reapers, and Israel builds its own. But the three newcomers — Nigeria, Pakistan and Iraq — all took advantage of China's growing exports of the unmanned aircraft systems that are reshaping modern warfare.' W.J. Hennigan, ‘A Fast Growing Club: Countries That Use Drones for Killing by Remote Control’, Los Angeles Times, 22 February 2016.  Almost 80 countries deploy surveillance drones and of those 80, more than 20 either have or are developing armed drones. The use of drones by so many nations is becoming a huge challenge for those involved with international law and the rules of engagement.

Drones and International Law

Not only did the 9/11 terrorist attacks change the way the US military targeted and attacked its enemies, it also changed the way international law defined its enemy. 'This is why drones and the employment of drones as launch vehicles for missiles present such a challenge for lawyers and human rights advocates.' R. Brooks, ‘Drones and the International Rule of Law’, 28 Ethics and International Affairs 1 (2014), 83-104.  It is not that US drone strikes actually violate international law. Ironically, US drone strikes challenge international law because they don’t conform to a straightforward legal categorization used in international law prior to 11 September 2001.

Along with the rise of the use of drones came new legal theories to justify the use of these weapons. Also words like 'armed attack', 'civilian', 'self-defence', and 'proportionality' gained new meanings, as war zones had no defined boundaries. R. Brooks, ‘Drones and the International Rule of Law’, 28 Ethics and International Affairs 1 (2014), 83-104.

Another controversial issue is what constitutes hostile territory and what constitutes a battlefield. 'While much of drone use is shrouded in secrecy, it is widely known that the U.S. has attacked targets by drone in Pakistan, Yemen and Somalia. All of these places are outside of what is considered by international law to be a “hot battlefield”. In Pakistan alone the number of suspected strikes rose from 4 in 2007 to a peak of 122 in 2010.' R. Brooks, ‘Drones and the International Rule of Law’, 28 Ethics and International Affairs 1 (2014), 83-104.

Finally, most important for the future use of drones is the question of what constitutes self-defence. Is there a danger that different interpretations of those words can lead to greater conflicts as the use of unarmed drones expands internationally? This is the challenge for diplomats, military leaders and human rights advocates in the 21st century. 

Countries with Armed Drones: China, Iran, Iraq, Nigeria, Pakistan, Somalia, South Africa, United Arab Emirates, United Kingdom, United States. P. Bergen, D. Sterman, A. Sims, A. Ford, C. Mellon, ‘World of Drones 3: Who Has What: Countries With Armed Drones’, New America.

Countries with Drones Used in Combat:  Iran, Iraq, Israel, Nigeria, Pakistan, Turkey, the United Kingdom and the United States. P. Bergen, D. Sterman, A. Sims, A. Ford, C. Mellon, ‘World of Drones 2: Who Has What: Countries With Drones Used in Combat’, New America.

Non State Actors with Drones Used in Combat: Hamas, Hezbollah, ISIS and Libyan Rebels. P. Bergen, D. Sterman, A. Sims, A. Ford, C. Mellon, ‘World of Drones 5: Non-State Actors With Drone Capabilities’, New America.

Countries Developing Armed Drones: France, Greece, India, Italy, Pakistan, Russia, Spain, Sweden, Switzerland, Taiwan, and Turkey. P. Bergen, D. Sterman, A. Sims, A. Ford, C. Mellon, ‘World of Drones 4: Who Has What: Countries Developing Armed Drones’, New America.

Countries Producing Drones Domestically: Algeria, Argentina, Armenia, Australia, Austria, Azerbaijan, Belgium, Brazil, Bulgaria, Canada, Chile, China, Columbia, Czech Republic, Denmark, Egypt, Estonia, Ethiopia, Finland, France, Georgia, Germany, Greece, Hungary, India, Indonesia, Iran, Israel, Italy, Japan, Jordan, Latvia, Malaysia, Mexico , the Netherlands, New Zealand, Nigeria, Norway, Pakistan, Peru, Philippines,Poland, Portugal,  Republic of Serbia, Russia , Singapore,South Africa, South Korea, Slovakia, Slovenia, Spain, Sweden, Switzerland, Taiwan, Tunisia, Turkey, Ukraine, United Arab Emirates, United Kingdom, United States, Uruguay, Venezuela, Vietnam.  P. Bergen, D. Sterman, A. Sims, A. Ford, C. Mellon, ‘World of Drones 4: Who Has What: Countries Developing Armed Drones’, New America.

Last updated on: 03 August 2017

Unmanned Combat Aerial Vehicles (UCAVs) can have severe humanitarian, environmental and societal consequences.

An armed drone is an Unmanned Combat Aerial Vehicle (UCAV). It is an aircraft piloted by a military drone pilot sometimes thousands of miles away. It is a UAV delivery system outfitted with offensive munitions. Armed drone is a delivery system of offensive weapons and munitions. G.Udeanu, A. Dobrescu, M. Oltean, ‘Unmanned Aerial Vehicle in Armed Operations’, Proceedings of the Scientific Conference AFASES 1 (2016), 199-205. Typically it is armed with Air to Surface (ASM) or Air to Air missiles (AAM). The most commonly used armed drones are the MQ-9 Reaper and Predator variants flown by the US Air Force. Armed Drones have become so prevalent that the US had 167 drones in 2001 and more than 7000 in 2012. International Human Rights And Conflict Resolution Clinic (Stanford Law School) And Global Justice Clinic (NYU School Of Law), 'Living Under Drones: Death, Injury, And Trauma To Civilians From US Drone Practices In Pakistan', September 2012.

To seek more information on the impact of the weapons/munitions used by armed drones, refer to Air to Surface or Air to Air missile systems.

Tactical Uses

The Reaper and Predators are used often against time-critical High Value Targets (HVTs). This target is one which is considered valuable and offers a limited time window to strike. A limited time window is also referred to as 'dynamic'. The drones are used against HVTs regularly because of their stealth capabilities that allow them to get close and observe from medium altitude without risk of life. The Reapers and Predators can also circle above and wait for hours, until an opening appears, to strike. 33 Armada International 4 (2009), 20-47.

Signature Strike: The US often will target 'individuals that match a pre-identified "signature" of behaviour that the US links to militant activity or association.'

Personality Strike: Strike intended for an identified individual. HVTs fall under this category.

The drones are most often used against low-level militants. Since 2008, of the 500 militants that the CIA has believed to have killed 25 were mid-to-high level organizers, 14 were top-tier militant targets, the rest were low-level militants. International Human Rights And Conflict Resolution Clinic (Stanford Law School) And Global Justice Clinic (NYU School Of Law), 'Living Under Drones: Death, Injury, And Trauma To Civilians From US Drone Practices In Pakistan', September 2012.

Armed drones weapon systems are being created to 'conduct pre-emptive and reactive suppression of enemy air defence missions effectively and affordably.'  Armed drones can also strike armoured targets or structures depending on the payload. Armed drones are almost a one-size-fits-all because the target can be anything depending on what weapons systems can be outfitted. They can handle many different operations: fire suppression, psychological warfare, anti-aircraft, anti-armour, anti-personnel, shock and awe, general bombing.  


Armed drones are designed to be efficient and precise to minimise collateral damage. Armed drones originally were not that precise but over time the technology and research has improved to minimise error. International Human Rights And Conflict Resolution Clinic (Stanford Law School) And Global Justice Clinic (NYU School Of Law), 'Living Under Drones: Death, Injury, And Trauma To Civilians From US Drone Practices In Pakistan', September 2012.

The MQ-9 Reaper is generally equipped with four (ASM) Hellfire Missiles and two GBU-49 Enhanced Paveway II bombs. The Hellfire Missiles are meant to strike fast and with great accuracy to ensure destruction of target. The Hellfire Missile is fast and accurate enough to strike a moving vehicle. The missile was designed for long-range supersonic precision attacks on heavily armoured cars. The bombs are for larger targets like a strategic building or bunker. Some experimental drones are being developed to dogfight and deliver Air to Air missiles. 33 Armada International 4 (2009), 20-47. (For more information refer to 'Aerial Warfare' below).


Armed drones are dual-use, they have anti-personnel and anti-material uses. Armed drones are designed to carry a variety of payloads. The payload is specific to the mission objectives. Common weapon systems railed on an armed drone are air-to-surface/air-to-air missiles or laser guided bombs.

They are continually developed to allow new weapons systems and payloads.

For example, directed energy weapons such as high-powered microwave (HPM) may be on armed drones in the future to 'suppress enemy air defences, and disable command-and-control nodes and other electronic equipment.' Weapon/munition developments will only increase the effectiveness of armed drones.

Armed drones are designed to mitigate the penalties of having a human pilot: weight, size, cockpit, armour, flight controls, ejection seat, and environmental concerns like oxygen and pressure. This leads to less maintenance required which is a logistical advantage.

Drone technology allows some armed drones the ability to fly for 40 hours straight. Many can refuel mid flight. This allows combat drones to stake out a location for hours waiting for the ideal moment to strike. 'Drones' 40 Military Technology 5 (2016) 73.

Aerial Warfare

Armed drones are currently in research and development in many companies and states to engage in aerial warfare. Systems are being developed to replace manned aircraft with AI pilots that have greater dogfighting abilities.

For example, since 11 July 2016, Kratos Defence & Security Solutions. Inc has a contract with the US government of $40.8 million, with a potential of an additional $100 million, to create armed drones with aerial warfare capabilities. Kratos Receives Low-Cost Attritable Strike Unmanned Aerial System Demonstration Contract Award’, KRATOS, 11 July 2016.

Armed drones humanitarian impact is addressed in the entries dealing with Air to Surface and Air to Air Missiles (health impact of explosives). Material damage and environmental damage in relation to missiles are also addressed in the above mentioned entries.

The US has very low civilian casualty numbers and it is attributed to their definition of a civilian, presuming that, unless proven otherwise, individuals killed in strikes are militants.


Information on casualties from armed drones are widely disputed. The information is laid out to show who reports what information.

Casualty Estimates:

New America Foundation’s Year of Drone reports that in Pakistan since 2004, there has been an estimate of 1,584 to 2,716 'militants', between 152 to 191 'civilians', and 130-268 'unknowns' killed. 'Unknowns' are those whose remains are far past recognition or whose past as either civilian or militant was unknown. P. Bergen, D. Sterman, A. Sims, A. Ford, 'Drone Strikes: Pakistan', New America.

The Long War Journal reports that drones have killed 2,396 leaders and operatives from Taliban, Al Qaeda, and allied extremist groups in Pakistan since 2006, as well as 138 civilians. B.Roggio, A. Mayer, 'Charting the Data for US Air Strikes in Pakistan, 2004-2012', Long War Journal, 16 September 2012; as cited by International Human Rights And Conflict Resolution Clinic (Stanford Law School) And Global Justice Clinic (NYU School Of Law), 'Living Under Drones: Death, Injury, And Trauma To Civilians From US Drone Practices In Pakistan', September 2012, p 32.

According to United States Air Force data, 963 missions with at least one weapon release were conducted, with 2,127 total weapons released.

For concrete numbers of deaths and injuries through drone strikes in Afghanistan, Pakistan, Somalia and Yemen, see 'Drone Warfare', The Bureau of Investigative Journalism.

Example of casualties:

'In one drone attack in Pakistan, instead of striking a Taliban hideout, missiles hit the house of Malik Gulistan Khan, a tribal elder and member of a local pro-government peace committee. Five members of his family were killed. “I lost my father, three brothers, and my cousin in this attack”, said Adnan, his 18 year-old son. Adnan’s uncle claimed, “We did nothing, have no connection to militants at all. Our family supported the government and in fact…was a member of a local peace committee.” The family provided the Center for Civilians in Conflict with detailed documentation of the deaths of the five family members, including a report from the Assistant Political Agent of South Waziristan and a local jirga requesting that the government pay compensation.' 'The Civilian Impact of Drones: Unexamined Costs, Unanswered Questions', Center for Civilians in Conflict and Columbia Law School, 2012, p 21.

Even with the report and facts found it is unlikely for the family to receive any compensation. Strikes like this can encourage terrorism from the close and extended family, or the situation is used as propaganda for terrorists.

Armed drones often use the Hellfire Missile against surface targets, both personnel and material. The blast radius of the Hellfire can be around 15-20 meters. The missile can injure or kill through shrapnel, pressure, or incineration. Common missile strike wounds are shrapnel, burns over body, vision/hearing loss, and limb amputation.

'They destroy human beings….There is nobody left and small pieces left behind. Pieces. Whatever is left is just little pieces of bodies and cloth.' International Human Rights And Conflict Resolution Clinic (Stanford Law School) And Global Justice Clinic (NYU School Of Law), 'Living Under Drones: Death, Injury, And Trauma To Civilians From US Drone Practices In Pakistan', September 2012, p 94.

Armed drones impact the ability of medical services to reach the victims. Many targets are struck numerous times in what is referred to as a 'double tap'. This creates an environment where the emergency health services or nearby citizens can not start to save the injured for fear of a second strike. First responders have been killed attempting to rescue the injured. Some humanitarian workers have a six hour mandatory delay when going to a strike site, to avoid a double tap. International Human Rights And Conflict Resolution Clinic (Stanford Law School) And Global Justice Clinic (NYU School Of Law), 'Living Under Drones: Death, Injury, And Trauma To Civilians From US Drone Practices In Pakistan', September 2012, pp 74ff.

Material Damage

Surface Targets:

Armed drones can destroy strategic installations: radio centres, missile launch sites, weapon caches, bunker, small-medium structures. Armed drones are a delivery system that carries a payload of missiles/bombs that can severely damage or destroy any structures listed above.

Aerial Targets:

The armed drones of aerial combat in the near future will have offensive capabilities to destroy any air threats. The weapons system will most likely be Air to Air missiles or a laser based weapon. 

Environmental Impact

The weapon systems and munitions on the armed drones do the real damage to the environment and society. Armed drones themselves only do damage against the atmosphere. Drones pollute in the same way any other aircraft does. The fuel burned in flight creates carbon monoxide. The US Navy is planning on replacing a third of its fuel use with biofuels, including for combat drones. D. Carrington, ‘US Military Combines Green and Mean to Fly Drones on Biofuels’, The Guardian, 15 March 2012. 

Drones further create noise pollution. The production of noise from military aircraft has variable impacts on wildlife, which encompass primary, secondary, and tertiary effects. These effects can occur over an acute or chronic timescale representing both sub-lethal and lethal impacts that have the potential to cause permanent damage; a factor that is influenced by acoustic duration, intensity, and the biology of the specific species. Primary effects can include eardrum rupture, shifts in hearing abilities (either temporary or permanent), and/or auditory signal masking (e.g. unability to identify noises from prey, predators, or mates). Secondary effects are related to physiological impacts, which can lead to impediments in reproduction, foraging behaviour, and natural habitat use of wildlife residing in areas where aircraft noise is prevalent. Tertiary impacts consist of a combination of primary and secondary effects that can lead to population declines, species extinction, and habitat degradation. M.J. Lawrence et al, 'The Effects of Modern War and Military Activities on Biodiversity and the Environment', 23 Environmental Reviews 4 (2015) 443, 444.

Air-to-ground strikes can destroy natural habitat and also increase wildlife mortality rates. Both of those can lead to a localized population decline. The armament used can deforest an area, create craters, and destabilize and contaminate soil. M.J. Lawrence et al, 'The Effects of Modern War and Military Activities on Biodiversity and the Environment', 23 Environmental Reviews 4 (2015) 443, 444.

Societal Impact

Armed drones attempt to limit collateral damage but many civilians have been killed. The US is the main country that operates combat drones but yet rarely investigates into strikes that have occurred. The US doesn’t always recognize the strikes either. This lack of transparency and acceptance of guilt leads to much social anger and conversation on the topic of combat drones. 'The United States pays heavily for its statements denying the civilian impact of drone strikes. It loses support in affected communities who feel lied to and drives peoples into the arms of militant groups who capitalize on US silence to shape the narrative. Refusal to satisfactorily disclose accurate information about civilian deaths outrages human rights groups and compels them to assume that the numbers are too horrific to fathom.' 'Drones Reports Reveal Problems', Friends Committee on National Legislation. Terrorist organizations create propaganda videos using footage of drone strikes and killings to further their public support and gain membership. Drone operators can only estimate the number of civilians killed because they do not have eyes on the ground. Human rights groups demand that compensation be paid for innocent deaths. 'Drones Reports Reveal Problems', Friends Committee on National Legislation. Compensation is unlikely given the fact that state actors have not taken responsibility for all strikes.

'Along with the human costs, drones also destroy local infrastructure, cripple local economies, challenge local customs and increase poverty. The emotional and psychological costs of such dislocation and devastation, particularly on children, are deeply felt.' 'Drones Reports Reveal Problems', Friends Committee on National Legislation. This emotion is exploited by terrorist and rebel groups to recruit men and women into their ranks. The US has seen these effects the most from drone strikes in Pakistan. 'The ill-will spread by drone strikes in Pakistan are not reducing the threat of terrorism but increasing it. While many in Pakistan’s northwest once had positive views of the United States, new polling demonstrates the anti-American effect of drone strikes.' 'Drones Reports Reveal Problems', Friends Committee on National Legislation.

Local infrastructure can be destroyed in drone strikes. There have been reports of local schools being destroyed in Pakistan. 'The Civilian Impact of Drones: Unexamined Costs, Unanswered Questions', Center for Civilians in Conflict and Columbia Law School, 2012, p 25. If any place of business is destroyed the local economy can suffer for years after a single strike. A farmer could have property loss if a drone strike destroys his equipment or damages his crops. If homes are destroyed, people become displaced and thrown into poverty. In Yemen, drone strikes have contributed to the violence that has displaced over 100,000 individuals. 'The Civilian Impact of Drones: Unexamined Costs, Unanswered Questions', Center for Civilians in Conflict and Columbia Law School, 2012, p 25.

Drone pilots are impacted by armed drones physiologically. The pilots can have a hard time adjusting to being at work and making a decision that kills people across the globe, and then going back to a domestic home after work. 'The US Air Force conducted a survey that showed that 46% of Reaper and Predator pilots and 48% of Global Hawk sensor operators suffered from "high operational’ stress.”' E. Bumiller, 'Air Force Drone Operators Report High Levels of Stress', The New York Times, 18 December 2011.

An argument has arisen that armed drones dehumanize war. Without a person present, a robot is doing the dirty work and many feel this is wrong. Some drone pilots become desensitized to drone strikes. The morality of using armed drones continues to be debated.

Drones do not have an immense impact by themselves; but rather the weapons systems aboard the drone. Once weapons are on board the Unmanned Aerial Vehicle (UAV) becomes an Unmanned Combat Aerial Vehicle (UCAV). The armed drone weapons can cause massive physical harm to people in the blast/shrapnel/burn radius, depending on the weapon used. Armed drones are harmful to psychological health with people fearing drones, leading them to  'shy away from social gatherings, and inhibited their willingness to carry out day-to-day activities and important community functions.' International Human Rights And Conflict Resolution Clinic (Stanford Law School) And Global Justice Clinic (NYU School Of Law), 'Living Under Drones: Death, Injury, And Trauma To Civilians From US Drone Practices In Pakistan', September 2012, p 55. The weapons can destroy local economies through loss of infrastructure and primary income earner homes. Armed drone strikes can make a local economy struggle to keep up with the cost of rebuilding infrastructure.

Last updated on: 03 August 2017