Six years after Saudi Arabia intervened in Yemen, booby-trapped drones have made the Houthi rebels a potent threat, enabling them to target distant Saudi cities and heavily guarded oil facilities.
While Riyadh has been locked in a hunt for an elusive enemy, the guerrillas have made great strides in developing unmanned aerial vehicles that have become their go-to weapon after long relying on Cold War-era ballistic missiles.
The “Made in Yemen” UAVs have become a complex arsenal that the rebels, famed for their infantry skills in Yemen’s rugged mountains, are steadily turning into an air force.
Here is a look at the types of drones in Houthi hands and the threats they pose:
Homegrown?
Saudi Arabia and the United States have long accused Iran of supplying the Houthis with weapons, a charge Tehran denies.
However, the rebels possess an array of military equipment, including tanks and Scud missiles bought from the Soviet Union in the 1970s, that they acquired from Yemeni army depots after taking control of the capital Sanaa in 2014.
As for the UAVs, the rebels say they manufacture them domestically, although analysts say they contain smuggled Iranian components.
According to a report by the Missile Defense Project of the Center for Strategic and International Studies (CSIS), components are smuggled from neighboring Oman into Yemen’s nominally government-held Mahra province, and then by small boat along the coast.
A UN report in 2019 confirmed that the Houthis “retained access to the critical components, such as engines and guidance systems, from abroad.”
In September that year, Saudi energy giant Aramco’s Abqaiq processing plant and Khurais oilfield were hit by air strikes, halving the kingdom’s crude output. The rebels claimed the attack, but Riyadh and Washington accused Iran of carrying it out.
Attack, Surveillance
The most advanced Houthi drone is the Samad-3 which can be fitted with 18 kilograms of explosives and has a range of 1,500 kilometers (930 miles) and a top speed of 250 km/hour, according to rebel media sources and analysts.
Next are the Qasef-1 and Qasef-2, which have a range of 150 km and can carry a payload of 30 kg of explosives.
Other UAVs include reconnaissance drones with shorter ranges — including the Rased (35 km), Hudhhud (30 km), and Raqib (15 km).
The drones use GPS guidance and “fly autonomously along pre-programmed waypoints” towards their targets,” CSIS experts wrote in a 2020 report.
On March 11, the rebels unveiled seven new types of drone but without specifying their range and power. They included a new version of their most sophisticated drone, the Samad-4.
Long-Term Threat
The Houthis have used their drone attacks as part of a strategy to influence any future peace negotiations and put Saudi Arabia under pressure while they advance on the ground, analysts say.
Their aerial attacks intensified when they resumed a campaign last month to take control of Marib, the government’s last stronghold in the north.
Since the beginning of the year, the kingdom has acknowledged at least 45 drone attacks. Three of those hit oil facilities and airports in the south and east, but significantly the capital Riyadh, some 1,000 km from the Yemeni border, also came under attack.
“Houthi attacks on Saudi Arabia are likely to continue and are probably being adopted as a more permanent strategy, particularly while the Houthi are widening their offensive against Marib,” IHS Markit said earlier this month.
Saudi’s US-made Patriot missile defense system — which already appears to have a mixed record in intercepting launches from Yemen — is not primarily designed to repel low-flying drones, experts say.
Saudi Arabia possesses 80 standalone air defense radars, but many of these are older systems dating back several decades.
On the road to the holy city of Mecca, and from a bridge overlooking the airport in the western city of Jeddah, air defense systems are clearly visible.
But the attacks are also likely to “increase in range and target set, posing damage risks to assets in the wider Gulf,” added IHS Markit.
The rebels have also threatened to target the gleaming cities of Abu Dhabi and Dubai in the United Arab Emirates, a country which has also recently opened a nuclear power plant.