Analysis: How Houthi Forces Are Piercing Saudi Air Defenses

Yemen’s Houthi movement, also known as Ansar Allah, has intensified its offensive against Saudi Arabia, employing a combination of ballistic missiles, cruise missiles, and drones to strike deep within the kingdom. The escalation culminated on Saturday with an attack on King Khalid International Airport in Riyadh that killed 12 people and wounded 309, marking the deadliest incident in the country in over a decade.

In the wake of the assault, Saudi Arabia’s civil aviation authority suspended operations and diverted flights, while the United States and United Kingdom issued new travel advisories. The Houthis have claimed responsibility for previous attacks on the airport earlier in the week and have warned residents to avoid Saudi aviation hubs.

Saudi Arabia maintains one of the most heavily armed militaries globally, featuring sophisticated multi-layered air defense networks. Despite this, the Iran-backed group has significantly expanded its arsenal since seizing Sanaa in 2014. Their weapons have previously reached Israel, and recent displays of accuracy have allowed them to target specific high-value sites such as airports and oil facilities.

The Houthi Arsenal

While the specific weapon used in the Riyadh airport attack remains unidentified, the Houthis have launched hundreds of drones and missiles at Saudi targets since 2015. They have also targeted Israel and vessels linked to Israeli interests since October 2023, often mixing drones and missiles of varying speeds to overwhelm defensive systems.

Key assets in their inventory include the Palestine-2, a two-stage solid-fuel medium-range ballistic missile with an estimated range of 2,000 kilometers and hypersonic capabilities. They also utilize the Toufan, believed to be a variant of the Iranian Ghadr missile, with a range between 1,350km and 1,950km. These weapons, some equipped with cluster warheads, have successfully breached Israeli air defenses.

Shorter-range systems, such as the Burkan and Badr series, are also employed for cross-border strikes. Experts note that the Houthi missile inventory is predominantly derived from Iranian technology with some Chinese influence. Nawaf Obaid, a senior fellow at King’s College London’s War Studies Department, stated that the group shows little evidence of significant indigenous innovation, focusing instead on producing lower-end drones and missiles.

Challenges for Saudi Defenses

Saudi authorities report shooting down multiple projectiles recently, including ballistic missiles aimed at the capital on Thursday. However, they failed to intercept the projectile that struck Riyadh on Saturday. Obaid noted that given the kingdom’s vast size and border with Yemen, some penetration of air defenses is inevitable, emphasizing that dozens of attempts are thwarted for every successful strike.

Wolfgang Pusztai, a security analyst, explained that Saudi ballistic missile defenses were primarily designed to counter Iranian threats. However, rising Houthi attacks may force a reorientation of these systems toward Yemen. Additionally, interceptor stockpiles for Patriot and THAAD systems have been strained, having been rapidly depleted during earlier conflicts involving US allies.

Strategic Limitations

Despite their ability to disrupt civilian infrastructure, the Houthis face significant constraints, including a UN arms embargo, a prolonged Saudi blockade, and multi-front combat within Yemen. Obaid observed that while the Saudi-led coalition holds military superiority, the Houthis can still dominate global headlines through sporadic strikes on a nation with immense economic visibility as the world’s top crude oil exporter.

The exact size of the Houthi missile stockpile remains unknown, raising questions about their capacity to sustain attacks while fighting a ground war. Saudi air campaigns have focused on destroying Houthi missile depots and drone production facilities, inflicting substantial damage. Pusztai suggested that the Houthis may possess only a limited number of short-range ballistic missiles, making saturation attacks unlikely. Instead, they may opt for single missile strikes on less-defended civilian targets to maximize strategic impact, such as disrupting air traffic.