R-360 Neptune

R-360 Neptune (Р-360 «Нептун») is a Ukrainian subsonic cruise missile with all-weather capabilities developed by the Luch Design Bureau in Kyiv as an anti-ship missile, with a later variant for land attack. Neptune's design is based on the Soviet Kh-35 subsonic anti-ship missile, with substantially improved range, targeting and electronics equipment. It has a range of over 200 kilometres.

The system requirement was for a single missile to defeat surface warships and transport vessels with a displacement of up to 9,000 tonnes, either in convoys or moving individually. The first training missile divizion (battalion) entered service with the Ukrainian Navy in March 2021, with the first operational naval use in 2022. The land-attack variant has a new guidance system and was first fielded and used in 2023.

Development
The missile was first revealed at the 2015 Arms and Security international exhibition in Kyiv.

According to information from open sources, the first flight examples of the cruise missile were manufactured in the second quarter of 2016. Production of advanced missile systems took place in cooperation with other Ukrainian companies, including Artem Luch, Motor Sich (MS400 turbofan engine), ZhMZ Vizar Kyiv, Radionix (seeker) and Arsenal SDP SE (navigation system).

The first tests of the system were conducted on 22 March 2016, attended by Secretary of the National Security and Defense Council (NSDC) Oleksandr Turchynov. In mid-2017, Neptune missiles were tested concurrently with Vilkha launchers and missiles. The test results and capabilities of the Neptune were not made public, unlike those of the Vilkha. According to the press service of the NSDC, the first successful flight tests of the system took place on 30 January 2018. On 17 August 2018, the missile successfully hit a target at a range of 100 km during test firings in southern Odesa Oblast. On 6 April 2019, the missile was again successfully tested, hitting targets during tests near Odesa. According to President Petro Poroshenko, the Neptune system would be delivered to the Ukrainian military in December 2019.

After the withdrawal of the United States and Russia from the Intermediate-Range Nuclear Forces Treaty, Ukraine announced that it was considering developing intermediate-range cruise missiles. Ukraine signed a memorandum with Indonesia on concluding a contract for the supply of Neptune missiles, first reported in December 2020. Thus, Indonesia may become the first foreign buyer of Neptune, according to Defense Express with reference to the Ukrainian special exporter State Enterprise (SE) "Progress".

In March 2021, the Ukrainian Navy obtained the first training missile battalion of the RK-360MC Neptune.

Operational history
On 3 April 2022, during the Russian invasion of Ukraine, Ukrainian sources claimed that the RUSSIAN FRIGATE Admiral Essen had been damaged by Ukrainian forces. Later, Oleksiy Arestovych, a freelance adviser to the Office of the President of Ukraine, clarified that Admiral Essen had been hit by a Neptune missile. The Russians did not comment on the claim and the ship continued its mission as normal.

On 13 April 2022, Ukrainian sources claimed the RUSSIAN CRUISER Moskva was hit by two Neptune missiles, resulting in a fire and subsequent explosion of a shipboard ammunition store. The Russian Ministry of Defence stated, without discussing the cause, that a fire had caused munitions to explode and the crew had been fully evacuated. Russia reported the vessel as still being afloat later in the day of the fire, but Russian state media subsequently reported that she had sunk in inclement weather while being towed.

According to Thomas Shugart, a former U.S. Navy submarine commander, Slava-class cruiser s like Moskva have been typically "known for their offensive punch, not for their defensive systems or their damage control". Moskva was one of the largest warships sunk in combat since World War II. The successful use of the Neptune system to sink the warship was cited by Ukrainian Defence Minister Oleksii Reznikov as giving confidence to Ukraine's allies that more weapon supplies to Ukraine would be worth it.

A land attack variant was being designed and, as of April 2023, was close to completion. The Neptune missile was initially designed to hit ships at sea. According to a Ukrainian official: "Ukraine is working to modify Neptune missile to strike land targets... A new guiding/homing system is required, but Ukrainians are working on that... Once we get that, the Neptunes can hit targets 360 km (about 225 miles) away. We are pretty close."

On 23 August 2023, according to Ukrainian media reports, a modified R-360 missile was used to help destroy a S-400 missile system radar, deployed on Cape Tarkhankut in Crimea since 2016. On 14 September, Ukrainian forces subsequently claimed to have destroyed S-400 missile systems near Yevpatoriya using drones and Neptune missiles.

On 26 March 2024, Ukraine claimed to have struck the Konstantin Olshansky with a Neptune missile. This vessel was seized from Ukraine in 2014, when Russian forces took control of the Crimean peninsula.

On 9 April 2024, Russian forces claimed to have intercepted a Neptune missile near the Crimean coast.

On 21 April 2024, a video was released from Sukharnaya Bay, Sevastopol that allegedly shows the salvage ship Kommuna hit by a Ukrainian Neptune missile. Kommuna took part in salvage efforts after Moskva was hit in 2022.

Ukraine is working on extending the range of the missile to 1000 km while increasing production tenfold.

On 31 May 2024, Ukraine fired several Neptune missiles at an oil depot attached to Port Kavkaz, Krasnodar Krai. Russian officials claimed to have shot down the missiles. Ukrainian officials and Russian opposition reported a fire and damaging three petroleum tanks.

Design
When deployed, a Neptune coastal defence system comprises a truck-based USPU-360 mobile launcher, four missiles, a TZM-360 transport/reload vehicle, a RCP-360 command and control vehicle, and a special cargo vehicle. Czech Tatra T815-7 trucks replaced prototype KrAZ vehicles. The system is designed to operate inland up to 25 km from the coastline.

A Neptune missile including rocket motor is 5.05 m in length, with a cross-shaped hard wing. Neptune missiles are designed to be housed in transport and launch containers with dimensions 5.3 x. The system has a maximum range of about 300 km. A single missile weighs 870 kg, of which 150 kg is the warhead. It uses a Motor Sich MS400 engine which has a high thrust-to-weight ratio.