Attacks Using Unmanned Aerial Systems (UAS)

On 10 October 2018, FBI Director Christopher Wray testified before the Senate Homeland Security and Governmental Affairs Committee on “Threats to the Homeland”.  The following is an edited extract from the testimony concerning UAS:

“The threat from UAS in the US is steadily escalating.”  “The FBI assesses that…UAS will be used to facilitate an attack in the US against a vulnerable target, such as a mass-gathering.  This risk has only increased in light of the publicity associated with the apparent attempted assassination of Venezuelan President Maduro using explosives-laden UAS.” 

Some of the subsequent media reporting of this testimony assumes that such attacks are reasonably easy.  This may stem from the number of UAS in commercial use (package deliveries, event filming, geospatial surveillance, pipeline integrity etc) is rapidly expanding.  However, there are many factors that need to be accounted for before UAS can be used in a successful attack.

·         The example of an attack against a mass-gathering would need to take into account such factors as: the weather, environmental conditions, the payload in relation to the density of people at the target, whether navigational line-of-sight is required or is the mass-gathering defined in time and space.  It should also be noted that most media reporting considered a mass-gathering as an event (sporting event etc), but the daily rush-hour at a transit-hub or a regular meeting of a large number of people are also mass-gatherings.  In the case of a mass-gathering, a single UAS may not achieve the required effect for targeting or payload.

·         Discussion has also focussed on chemical or biological attack against a mass-gathering.  In addition to the factors previously mentioned, effective dispersion of the payload is a challenge.  Indeed, creating the desired effect from aerosol dispersal of many agents, not in a enclosed space, would be a challenge.

·         The use of UAS for assassination (eg the alleged attempt on Venezuelan President Nicolas Maduro at a military parade on 04 August 2018) also face problems.  Not only is some understanding of the event required in advance, navigational line-of-sight is required to guide the UAS to the target.  The other problems of weather, environmental conditions, and payload also exist.  The growing use of Counter UAS technology will also reduce the likelihood of an effective attack.

While the commentary above relate to the use of single or low-multiple UAS, the use of a swarm of UAS may overcome some attack limitations but also raise a different scale of challenge.  Indeed, the attacker would have to purchase, modify and store x number of UAS, train for the attack, synchronise the swarm during execution and accept a loss of surprise (even though the precise target may not be known).

While terrorist (or criminal) use of UAS for an attack is a growing concern, the mounting of a successful attack faces considerable issues.