Don Shift Sends: What Northern Ireland Can Tell Us About The Threat Of Airborne IEDs

Don Shift is the author of Poor Man’s Air Force: A guide to how small drones might be used in domestic unrest or low intensity conflicts.

In Northern Ireland during The Troubles, the hardening of police stations (barracks) against car bombs and snipers resulted in PIRA attack methods changing. Many were modified or constructed over the years to incorporate greater protection. As the barracks were fortified, vertical attacks became necessary to get over the perimeter fencing and walls. Thrown Molotov cocktails and grenades gave way to mortars. In addition to changing the geometry of the attack vector, mortars provided standoff capabilities, allowing greater chance of anonymity and escape for the PIRA team.

Mortars were effective early on because while the barracks may have been protected laterally, their roofs could not be shielded. Fortification measures included reinforcing roofs. As physical hardening was expensive, it was cheaper to empty top floors to absorb blast, shrapnel, and debris without risk to personnel. More cost-effective measures included identification and surveillance of known and likely firing points while bases were equipped with mortar alarms and safety drills.

Highly maneuverable explosive-laden UA can defeat layered protection and target weak points. In the future, a terrorist with a killer drone could use its ability to fly in a non-ballistic trajectory to circumvent these outmoded defenses. Whereas a mortar might be harmlessly deflected by a hardened roof, a “kamikaze” drone may crash right through the glass of an office window and detonate in the offices of an anti-terrorist investigation unit.

Drones offer new attack geometry to defeat unidirectionally oriented defenses. The non-ballistic flightpath, maneuverability, and remote operation of UAS all offer far greater advantages to terrorists and insurgents than a mortar while adding greater precision. For groups who are challenged with obtaining military equipment like a mortar tube and bombs, a drone with a homemade explosive circumvents this disadvantage.

While the PIRA had to source its heavy weaponry internationally, often with the help of illegal arms dealers or foreign intelligence agencies, drone technology eliminates that problem for the modern insurgent. A modicum of chemistry knowledge is needed to create explosives and a hobbyist can modify a COTS airframe to carry out the mission. Though modified consumer-grade UAVs can never supplant military-grade weaponry, the ability and danger is there nonetheless.

Lethal raids aren’t the only offerings that would have been a helpful addition to the nationalist terrorists. UAS reconnaissance and surveillance could have gone a long way as they were meticulous planners who learned from their mistakes. Since PIRA couldn’t do BDA first-hand, they needed to gather any information by observation from beyond the police lines and by word of mouth. A second drone filming the attack would not only gather valuable propaganda video but also take care of the BDA aspect.

In addition to BDA, human intelligence was critical to terrorist operations. A large network of observers and informers were used to conduct clandestine activities including espionage, counter-surveillance, and attacks. Manpower needs could have been reduced, increasing the level of security with fewer potential leaks. More thorough and remote observation may have helped defeat shadowing by Special Branch investigators.

Though it should go without saying, had the PIRA had UAVs during The Troubles reconnaissance would have been much easier and attacks far more deadly.