Overview

The Poseidon is intended to serve as response to U.S. withdrawal from the ABM treaty and to increase the Russian capability to overcome the U.S. missile defense systems,^{[1]: 25 [20][2][3]} such as anti-ballistic missiles, etc.

The Poseidon warhead can contaminate a large area with radiation. For this purpose, the Poseidon is speculated to be equipped with a cobalt bomb.^[21][22] The Poseidon could be a radiological second strike weapon.^[23][24]

Normal (not salted) thermonuclear weapons cause radioactive fallout primarily through neutron activation of material at the detonation site. Unless the detonation happens at low depths in shallow waters, an underwater detonation will have its fallout greatly reduced, except for at the surface immediately above, near the base surge. Much of the radioactivity will be deposited in the sea, and be carried by ocean currents.^[25] Water (and air) will not form radioisotopes suitable for radiological warfare when neutron activated, however the seawater-salt will, and the seabed may.

If used against an aircraft carrier battle group, the battle group would have reduced chances of defending itself against it. The drone could detonate its very large warhead at standoff range, and anti-submarine warfare units would have very little time to react because of the speed at which it travels.^[26]

Specifications

The Poseidon appears to be a torpedo-shaped robotic mini-submarine which can travel at speeds of 185 km/h (100 kn).^[23][24][27] More recent information suggests a top speed of 100 km/h (54 kn), with a range of 10,000 km (5,400 nmi; 6,200 mi) and a depth maximum of 1,000 m (3,300 ft).^[28]

Typical depth of the drone may be about 50–100 meters (160–330 ft) for increased stealth features in low-speed stealth mode. Low depth in stealth mode is preferred because sound waves move to ocean floor and reduce radius of detection. Submarines use the same strategy in silent running mode.^[29]

It is 1.6–2 metres (5–7 ft) in diameter and 24 metres (80 ft) long.^[30] The warhead shown in the leaked figure is a cylinder 1.5 metres (5 ft) in diameter by 4 metres (13 ft) in length, giving a volume of 7 cubic metres (250 cu ft). Comparing this to the volumes of other large thermonuclear bombs, the 1961 Soviet-era Tsar Bomba itself measured 8 metres (26 ft) long by 2.1 metres (6 ft 11 in) in diameter, indicating that the yield is at least several tens of megatons, generally consistent with early reports of 100 megatons.^[31]

Body

Most likely, the high-strength body of the device is made of titanium alloys.

Powerplant

The National Interest compiled several unclassified defense sources from General Electric experts about the similar 601B project^[32][33][34] and they predicted low weight and compact gas-cooled nuclear reactor in the drone.^[35] Russian submarine designers say that a low-power reactor is preferred for Poseidon because a smaller reactor is less noisy.^[29]

Stealth technology

The development includes also use of stealth technology, to elude acoustic tracking devices.^[24][29][36] Poseidon uses a silent running strategy like other submarines. Its main stealth feature is its very low speed before it reaches the target area. Its high-speed mode activates upon reaching a short finish range (2–3 kilometers), when the probability of detection of the drone is considerably higher. It could travel for weeks toward enemy port cities, reaching high-speed only in the final stage.^[35]

Russian designers estimated the radius of detection of the drone will be about 2–3 km (1.2–1.9 mi) for 55 km/h (34 mph).^[29] A second important stealth feature of the drone is the special design of the pump-jet for clearance of the drone's acoustic signature to imitate the noise of civil ships.^[29]

A U.S. intelligence officer told CNBC that the Poseidon is difficult to detect and difficult to target in stealth mode.^[37]

Supercavitation

Poseidon is a family of drones, some of which are designed only for destroying coastal cities and thus rely on "stealth" capabilities rather than on high speed,^[29] others of which are primarily designed to attack carrier battle groups^[26] and were claimed to possibly harness supercavitation, like the VA-111 Shkval torpedo, to attain extremely high speeds (>230 mph) in attack mode.^[38][39] However, supercavitation devices have not been observed on the available footage of Poseidon.^[40] The Pentagon estimates maximum speed of the Poseidon to be about 56 kn (104 km/h; 64 mph) without the supercavitation option.^[41]

Launch platforms

The two ships speculated to carry the Poseidon are the Project 09852 modified Oscar-class submarine Belgorod and the Project 09851 Khabarovsk submarines.^{[24][30][42][43]} Oscar-class submarines could carry six Poseidon torpedoes at the same time for a total yield of up to 12-600 megatons.^[44][45]

According to some reports, Poseidon may have a seabed or mobile site launch option. In this configuration, known as Skif (Скиф) and patented by designer Alexander Shalnev,^[46] Poseidon can be staged on the sea floor in a special container as long as necessary. Russian auxiliary vessels Zvezdochka (Project 20180) and Akademik Aleksandrov (Project 20183), both of which feature ice-breaking capabilities, are involved in testing of Poseidon drones, indicating that these ships may be used as platforms for deploying and retrieving such a seabed version.^[47][48]