The Build-It-Yourself Bombs

The camera wobbles and the image pixelates as the cameraman tilts upward to catch the Syrian military helicopter drop its payload. The video, which has been viewed more than 76,000 times, follows the barrel bombs’ tumbling descent, the roar of their fall growing louder. The bombs hit their targets in a closely-packed urban area with an enormous crash, sending a huge plume of dark gray and white smoke, dust, and debris rising up as the building gives way. The video, reportedly from the Damascus suburb of Daraya, was uploaded by anti-government media activists from Syria in February. The accompanying video description refers to the weapons as barrel bombs — and ordnance tumbling from a Russian Hip helicopter, with visible fins, is likely just that. Similar to many of the videos available online of these bombings, the precise details of the attack in question, like the number of dead and wounded, are not known.

The Syrian air force’s indiscriminate use of barrel bombs against rebel-held targets across the country have caused widespread terror and helped fuel Syria’s growing humanitarian crisis. At least 240,000 Syrians are living under siege, and, as recently reported in Foreign Policy, barrel bombings are playing their part in preventing food shipments and medical supplies from reaching the neediest civilian populations of the war-battered countries. United Nations Secretary General Ban Ki-moon recently told the U.N. Security Council that Syria has seen "an intensified use of barrel bombs by government forces against civilian populations," with the attacks inflicting heavy damage to infrastructure and causing large number of civilian casualties.

Videos of these bomb drops and soot clouds populate YouTube — sometimes in disturbing mega-compilations. The videos from Syria are most often shot and disseminated by Syrian citizens documenting attacks on them, although one appears to have been shot from inside a Syrian military helicopter. Many mirror the one described above, training the camera first on the helicopter, then on the falling bomb, and then zooming in on the gray, brown and white soot cloud of another destroyed building and another group of dead Syrian civilians, their exact numbers unknown and unknowable.

Most Americans didn’t know barrel bombs existed until news of their widespread use in Syria began to emerge from the shattered country earlier this year. But the weapon — cheap and easy to manufacture — has long been used in both Iraq and Sudan as well. In Iraq, where the government has used barrel bombs against Sunni insurgent groups, including the Islamic State of Iraq and al-Sham, citizen journalists and media collaboratives have filmed and uploaded a handful of videos showing not the explosions themselves, but the remains of the weapons — dusty plates and barrels in craters and rubble — as evidence of the use of barrel bombs. The bombs haven’t just been used in the Middle East. In Sudan, government forces have used them against rebels and civilians in Darfur, South Kordofan and Blue Nile, causing widespread carnage. In contrast to the vast array of online footage from Syria, and even the few recent uploads from Iraq, no videos whatsoever seem to be available from the Sudan bombings.

The sheer number of videos is a godsend for scholars of the Syrian war, like Richard Lloyd, to pore over.* Lloyd has contributed to the detailed information made available by British investigative blogger Eliot Higgins, whose Brown Moses blog has become a trove of data on the Syrian conflict, including barrel-bomb technology. A 53-year-old from Spokane, Washington, Lloyd is a warhead technology expert at Tesla Laboratories and has spent the past year watching these videos and analyzing them for an understanding of the design and construction of Syria’s barrel bombs. Over the phone, he explains the time he spends trying to understand the way the weapon — increasingly a mainstay of Syrian strongman Bashar al-Assad’s war against his own people — has evolved. As a result of the amount of evidence available and Lloyd’s interpretation of it, a great deal more is known about the evolution of the barrel bombs and the impact of their use than had been available from the weapons’ earlier deployments in Iraq and Sudan. "I search all the videos every day," he says. "I watch the barrel bomb drop and analyze that. Analyze the helicopter. Watch it hit the ground. See if there’s an explosion."

From footage of a bomb’s aftermath, he analyzes the exploded ordnance for its design, its diameter, and the type of explosive used. When he watches footage of an explosion itself, Lloyd scrutinizes it to figure out the blast radius and estimate the damage, using the height of the soot cloud to determine the amount of explosive material in the bomb. Over the course of his analysis, he has managed to illustrate something of a timeline of Syria’s technological development of barrel bombs and to note some of the most important shifts in their design, ones that have affected their destructive force. The design shifts he has been able to observe range from a dramatic size increase to changes in the fuses and external attempts to keep the barrel bombs from tumbling around while they descend– evidence of the Syrian army’s investment in the use of these munitions.

Barrel bombs are about as far from a precision weapon as you can find. A U.S. drone can fire a missile into a moving car from tens of thousands of feet away; a barrel bomb is a crude device that is basically just tossed out of a helicopter or plane without any regard for where it lands. However hit-or-miss they may be, though, barrel bombs are an easily constructed way of creating fear. They’re typically built from oil drums, scrap metal, or rebar, and explosives, and they can cost as little as $200 to $300, Lloyd estimates. You get what you pay for: The bombs are often duds that fail to explode on impact or that destroy themselves in midair explosions. When they do hit, however, these bombs have the capacity to inflict extraordinary harm and steep casualties. In an especially bloody nine-day barrel-bomb offensive on the northern Syrian city of Aleppo in December 2013, barrel bombs are thought to have killed more than 300 people, 87 of them children. In one attack on the Masaken Hanano market, an activist reported to Al Jazeera that medics were "removing people in parts."

In many ways, barrel bombs are a kind of airborne version of the improvised explosive devices (IEDs) that were used to devastating effect in Iraq and Afghanistan. IEDs in the two war zones often functioned like land mines, with insurgents burying raw explosive or artillery shells underground and using garage-door openers or cell phones to detonate them when U.S. troops or vehicles passed by. The bombs were the leading killers of U.S. troops in both countries, leaving more than 3,000 dead while wounding more than 33,000 more. Do-it-yourself weapons like IEDs are a hallmark of insurgency and rebellion, of desperation and limited resources. Barrel bombs can be used by insurgents, but they are usually dropped from helicopters and aircraft belonging to state militaries. Either way, they serve the same purpose as a traditional IED: killing and wounding enemies cheaply and easily.

They’re also becoming increasingly popular. Barrel bombs have been in the news lately because of Syria, but an earlier incarnation was first seen on the battlefields of Iraq in 2007. This older version of the weapon consisted of "lob bombs," which functioned as crude mortars for the insurgents battling U.S. forces in the later years of the Iraq war. A predecessor of sorts to the barrel bombs seen in Syria and Sudan, they were built the same way: Emptied-out propane tanks were packed with explosives, scrap metal, and ball bearings. Rather than dropped from the sky, they were launched in an arc trajectory from ground level, usually from truck beds. Ordnance of the current heft and design of a barrel bomb requires helicopters, and helicopters virtually always mean a state army.

That was the case in Sudan in 2011, when government forces rolled barrel bombs and other unguided munitions out of the backs of Russian-made Antonov cargo planes against rebel and civilian targets in the South Kordofan and Blue Nile regions. The barrel bombs were among the bombs used in Sudanese forces’ indiscriminate aerial bombardments when conflict broke out in 2011 with the southern rebel group the Sudan People’s Liberation Army. One woman told Human Rights Watch investigators about the impact of a barrel bomb hitting her and a group of 25 other civilians as they made their way toward South Sudan in late 2011, saying "When [the bomb] hit, there was just smoke and dust and I couldn’t see anything. Moments later I saw my daughter and I called to her to see if she was injured. And then I saw the blood of my daughter. Within minutes the Antonov dropped a second bomb." These bombs were similarly used by Khartoum over the past decade in its campaign in Darfur, according to eyewitness accounts that were given to Amnesty International. Smith College professor Eric Reeves reported in 2012 that the Sudanese bombs "explode not with a large blast capability (and often do not explode at all), but have enough force to generate a hail of deadly shrapnel in all directions." He added, "They are not by nature a military weapon, but a tool for civilian destruction and terror." Sudan appears to have continued using the weapon. A recent Amnesty International report found that barrel bombs were among the ordnance dropped on South Kordofan in May.

Sudan has made wide use of barrel bombs, as has the Syrian government, and they have begun to return to Iraq as well. In May, an Iraqi army desperate to beat back insurgents from the Islamic State of Iraq and al-Sham (ISIS, and recently renamed the Islamic State) dropped the bombs on ISIS targets in the rebel-controlled city of Fallujah. Residents there described helicopters dropping barrel bombs on residential neighborhoods, coming across unexploded barrel bombs, and the sounds of large explosions and the wide areas of destruction that Human Rights Watch calls consistent with barrel-bomb attacks. An anonymous official in Anbar province confirmed the use of barrel bombs to Reuters, calling the bombings a "scorched-earth policy — the destruction of a whole area." The official said the Iraqi Army was using the barrel bombs because it lacked experience "in house-to-house fighting, which the rebels have mastered. That’s why they’ve resorted to this."

Syria, though, is where barrel bombs are increasingly a government’s weapon of choice, with catastrophic results for the rebels on the ground and the civilians caught in the crossfire. The insurgents’ acquisition of anti-aircraft weaponry has forced Assad’s helicopters to fly higher, which means the bombs are even less precise once they make their long way down to the ground. Assad’s growing use of the weapon, which has been confirmed and condemned by the United Nations, has helped Syrian engineers sharply increase the bombs’ power. In the early stages of their use, barrel bombs weighed between 100 and 300 pounds. Now their weight has multiplied; individual bombs range from 1,000 pounds to a full ton.

The lighter-weight bombs had been ignited with simple fuse wicks lit with cigars and had been pushed from Russian Hip helicopters. As the bombs changed in size, they evolved, with wicks giving way to impact fuses designed to explode on contact when they hit the ground. Barrel bombs have also been given crude fins to prevent them from tumbling around while they descend and to increase the likelihood that the bombs will land on the impact fuse. They have also been adapted to be carried by Russian Hind helicopters, which formerly could only transport and drop conventional bombs.

Packing chlorine-gas canisters inside the barrel bombs is another deadly addition. In May, Human Rights Watch said that there was strong evidence that Syrian government helicopters dropped the weapons on three towns in northern Syria in mid-April. Local doctors told the human rights group that the attacks killed at least 11 people and left 500 more with symptoms consistent with exposure to the toxic substance. Although it does not have the lethality of sarin, chlorine gas can still inflict harm, particularly on a population weakened by siege and already terrified by the prospect of chemical weapons. "Syria’s apparent use of chlorine gas as a weapon — not to mention targeting of civilians — is a plain violation of international law," Nadim Houry, the deputy Middle East and North Africa director at Human Rights Watch, said in a statement at the time. "This is one more reason for the U.N. Security Council to refer the situation in Syria to the International Criminal Court."

Barrel bombs are far from a perfect weapon, but however hit-or-miss they may be, they are a cheap way of creating fear. They often miss their targets, and design flaws lead to duds and midair explosions. When they do hit, however, these bombs have the capacity to inflict extraordinary harm and steep casualties. In some ways, however new these weapons may seem, they are a very old-school piece of technology: inelegant, blunt-force combinations of metal and high explosives, deployed with a heavy hand. Barrel bombs stand out in contrast with modern warfare’s vast array of skillfully engineered smart bombs and guided weaponry, all designed with precision in mind. Nevertheless, their continued use seems as much a part of future conflicts as the sleeker, higher-tech ordnance. Turns out that the future of the war may come from its past.

Correction, July 7, 2014: Richard Lloyd is an expert on weapons technology. An earlier version of this article incorrectly described him as an amateur scholar. (Return to reading.)