The feature allows Russian super rockets to fly around the Earth

General Sergey Karakayev, commander of Russia’s strategic missile forces, announced on May 13 that the test of the heavy intercontinental ballistic missile (ICBM), using liquid fuel RS-28 Sarmat, took place successfully, completing all set tasks.

The rocket launched from the Plesetsk spaceport in Arkhangelsk province at noon on May 12, hitting the designated target at the Kura training ground on the Kamchatka peninsula in the Far East. Russian President Vladimir Putin called this “an important event and an absolute success”.

The Russian Strategic Missile Forces said in 2019 that the RS-28 Sarmat has a range of 18,000 km. For comparison, the ICBM model with the longest range in US service today is the Minuteman III, which can reach targets at a distance of 14,000 km, while this figure for the Chinese DF-41 line is 12,000-15,000 km.

However, President Putin confirmed on May 12 that the Sarmat missile could reach much farther if launched by a special method. “The missile can not only fly on a conventional ballistic trajectory but also on a low trajectory, helping to reach a range of more than 35,000 km, doubling accuracy and capable of penetrating all current and future air defense systems,” he said.

The Russian leader appeared to be referring to a launch method similar to the Low Orbital Strike Weapon System (FOBS), which the Soviet Union developed and deployed in limited numbers during the Cold War.

Conventional ICBMs will fly on a fixed trajectory, with a maximum altitude of 1,200 km and plunge into the target at nearly 30 times the speed of sound. Meanwhile, FOBS uses an ICBM-like missile to put a reentry vehicle containing a nuclear warhead into low Earth orbit, only about 150 km above the ground.

It is unclear why President Putin said the Sarmat missile could only reach a range of more than 35,000 km if using a FOBS trajectory. In theory, this type of weapon can fly many times around the Earth and reach almost infinite range. The warhead will be present in space for a long time and will only descend on the target when required.

The Soviet Union’s purpose in developing FOBS was to bypass the US’s surveillance and air defense network, which was focused towards the North Pole to detect ICBMs flying from their opponents. The large flight range of FOBS will allow the Soviet Union to launch them in other directions, including around Antarctica, to reach North American territory.

A much lower flight altitude than traditional ICBMs also helps FOBS hide better from surveillance radar, even when launched in the direction of coverage of the enemy’s defense network.

“FOBS can attack from directions that radar cannot track, reducing the ability to predict where and when a strike will occur, let alone deploy countermeasures,” Tyler Rogoway, editor of the US military website War Zone, comment.

Each Sarmat shell is 35.5 m long, 3 m in diameter, carrying 10-15 independent re-entry nuclear warheads (MIRV) with a total power equivalent to 50 million tons of TNT explosives, accompanied by many types of decoys to deceive the enemy defense system. Sarmat can also mount three Avangard hypersonic glide vehicles or similar warheads in the future.

“The highlight of hypersonic glide vehicles (HGVs) like Avangard is the flight trajectory. Unlike traditional ballistic missiles, they fly on a relatively low and flat trajectory at hypersonic speeds, while also possessing the ability to maneuver throughout the entire journey. HGVs are much more difficult to detect and intercept than conventional retrosphere warheads,” said Russian military expert Dmitry Kornev, founder of the Military Russia project.

Rogoway also believes that HGVs can attack targets that deviate greatly from the fixed ballistic trajectory and are “almost impossible to intercept”.

However, the magazine’s writer Michael Pecks Forbes claim that FOBS are less accurate than traditional ICBMs. Once it bypasses Antarctica, it will still be detected by a network of warning satellites equipped with infrared sensors that detect engine exhaust. This flight direction also makes it take nearly an hour for the warhead to reach its destination, instead of 30 minutes like when flying over the North Pole.

“Perhaps a single FOBS launch would not cause alarm, but a mass launch is exactly what the US missile warning system is designed to detect,” Pecks said.

This also seems to be one of the problems that manufacturer Sarmat seeks to overcome. The Russian Ministry of Defense said the rocket’s propulsion stage operates for a relatively short time, significantly limiting the risk of being detected by satellites equipped with infrared sensors.

The FOBS program was canceled by the Soviet Union in the 1980s. The US Air Force said in 2021 that China is developing and testing similar weapons with HGV warheads, but the actual progress is unclear.

The RS-28 Sarmat is one of the six “super weapons” first introduced by President Putin in 2018. Russia initially planned to commission the Sarmat in 2020, but had to postpone the deadline due to the program’s slow progress. The first successful launch of a complete Sarmat missile took place in April 2022, followed by failed tests in February 2023 and September 2024.

“Its testing history has been quite erratic so far. Completing the Sarmat line will pave the way for Russia to deploy more strategic missiles in the future, potentially triggering a new arms race,” Thomas Newdick, editor of War Zone, warned.