P-15 Termit Anti-ship cruise missile

Zarvan · Apr 23, 2017

Known by the West as the SS-N-2 Styx, the P-15 Termit is the longest-lived and most successful cruise missile in the world, and the first missile to sink a warship in battle

Country of origin Soviet Union
Entered service 1960
Missile length 5.8 m
Missile diameter 0.76 m
Wing span 2.4 m
Speed Mach 0.9
Missile weight 2 300 kg
Warhead weight 454 kg
Warhead type HEDP
Range of fire 40 km (80 km, later versions)
Guidance Active radar and internal navigation system
Launch platform Surface ships and coastal batteries

The revolutionary Raduga P-15 Termit (Western code-name, SS-N-2 "Styx") was the first successful anti-ship cruise missile to achieve operational service. It was not the first such weapon, but previous missiles of this type such as the P-1 Strelka (SS-N-1 "Scrubber") were short-lived in service.

This missile had an unlikely origin as an attempt to produce a compact fighter aircraft, in the form of the Yakovlev Yak-1000, which first flew in 1951. This aircraft was characterized by a cropped delta wing, an all-flying tail with both vertical and horizontal stabilizers that were also of a cropped delta shape, and a cigar-like fuselage. Though it was quite fast (attaining an airspeed of Mach 1.7 for the first time in a manned flight), its fragile undercarriage design was ultimately its undoing, and the sole example was written-off after a mere taxiing mishap.

In the late 1950s, the design of the Yak-1000 later caught the attention of the MKB Raduga design bureau, who were tasked with developing an anti-ship missile of similar in size and performance, in order to defeat the numerous large warships then operated throughout the Western Bloc. A team under Alexander Yakovlevich Bereznyak (a co-designer of the Bereznyak-Isayev BI-1 rocket interceptor during World War 2) adapted to the design of the Yak-1000 into a radar guided missile with a different air inlet system and stabilizers, and an active radar homing guidance system (i.e., the seeker head emits its own radio waves, and homes-in on a reflection consistent with a proper target).

In testing, the P-15 demonstrated the ability to virtually demolish small warships, but it proved less effective than anticipated against the larger vessels it was mainly intended to defeat. For example, the incomplete Stalingrad battlecruiser herself was one of the target ships used for the P-15, and had the unique advantage of being indefinitely reusable; much to the surprise of the Soviet government, the Stalingrad was never significantly damaged, despite being pounded by over 100 direct hits from missiles of all types (including many P-15s) from 1956 to 1960.

Development was complete by 1960, at which time the P-15 Termit entered operational service with the Soviet Navy. It was originally intended as armament for mid-sized Soviet warships such as the Kynda class missile cruisers, as substitutes for the aforementioned canceled Stalingrad class, and the half-completed Sverdlov class light cruisers (i.e., only about half that were laid-down were completed). However, as the P-15 was recoilless upon launch, and relatively small, light, and inexpensive for its mission, its potential to arm much smaller warships was soon realized, and numerous corvettes, frigates, and even fast attack craft ended up being armed with them, giving small warships an equalizer against larger enemies.

The appearance of the P-15 is defined by its long cylindrical fuselage with a rounded nose and a tapered tail, steeply-swept trapezoidal wings and fins, and a small cylindrical booster on the aft underside. The wings are mid-mounted and located slightly aft of the midsection, while the stabilizers consist of a single vertical fin on top of the aft end, and two similar horizontal fins with a steep dihedral pitch. A slightly bulged spine is located on the forward underside of the missile, while several square-shaped access panels are located on top. The thrust nozzle on the tail is tiny compared to the rest of the missile, and thus easily overlooked. A rocket booster bottle is fitted to the underside of the tail, which is cylindrical in shape with a flat nose and a downward-curved conical thrust nozzle. As the booster bottle is fitted to the tapered underside of the tail, it is not parallel with the fuselage.

The fuselage and wings of the P-15 are primarily composed of simple sheet steel, while the radome is composed of radio-transparent fiberglass. The fuselage has an all-monocoque construction, with a mixture of cast and riveted sections. The liquid fuel that powers the motor is acidic and highly corrosive over time, and due to the relatively loose mechanical tolerances of the missile's overall assembly, the fuel often seeps into and sometimes out of the missile, causing corrosion on the underside. Several attempts were made to eliminate these fuel leaks throughout the P-15's production run, but the problem was never entirely resolved. Unfortunately, the fuel is also dangerously volatile and toxic, and must be handled with care.

The propulsion system consists of the aforementioned rocket booster bottle, and an internal sustainer rocket. The booster is used to propel the missile into the air up to a suitable speed for the sustainer to start and produce sufficient thrust to sustain the missile's flight. The booster burns-out and is jettisoned from the missile as soon as sufficient inertia is achieved. The launch of the P-15 Termit is a decidedly spectacular event, and it extremely loud and fiery (especially before the booster burns-out); as a result, the P-15 has a very strong launch signature that is easily spotted. Due to the properties of the aforementioned acid-based fuel, the P-15 can only be safely launched at temperature of between -15ºC to +38ºC. Between the very bright launch signature and the fuel's intolerance of low temperatures, Soviet regulations generally forbade launching the P-15 on warm days and cold nights.

The propulsion system is sufficient to allow the P-15 to attain a high subsonic speed within a minute of being launched, and retain that speed throughout the duration of its flight. The P-15 flies at an altitude of 100 m to 300 m above sea level (depending on the setting, and the variant), so its hardly a "sea-skimming" missile by modern standards.

Guidance is provided by the MS-2 seeker head, and I-band active homing radar system. The seeker contains both transmitters and receivers for radio waves, allowing the missile to find and illuminate its own target, and home-in autonomously. The MS-2 has a range of only 11 km at the P-15's flight altitude, so an Inertial Navigation System (INS) is also integrated into the guidance system, in order to keep the missile on-course until it finds a target. Upon achieving a lock at this range, the missile enters a shallow descent (1-2°) into the target. However, this guidance method is only effective against targets some 27 km away or further.

It is also possible to engage targets with the P-15 as close as 5.5 km, but due to the limitations of the on-board guidance system, it must employ semi-active radar homing guidance at short ranges. The target must be illuminated by a separate radar system at these ranges, such as the Harpun series of fire control radars.

The P-15 Termit employs a High Explosive Dual Purpose (HEDP) warhead, allowing it to penetrate relatively thick hulls and still cause extensive damage. This munition consists of 454 kg of RDX explosives and a copper charge liner (the mass ratio of which is unclear). As the missile is expected to retain a significant amount of fuel upon impact, the warhead was mounted behind the fuel cells, so that the resulting detonation would have a substantial incendiary effect inside the target.

It should be noted that the P-15's HEDP warhead frequently misidentified as a High Explosive Anti-Tank (HEAT) warhead. HEAT is another type of shaped charge munition, whose construction forcibly directs its blast energy into transforming the charge liner into as small and fast a penetrator as possible, resulting in a relatively small blast, but immense armor penetration. HEDP is essentially the antithesis of HEAT, as while it is shaped to allow greatly increased penetration (relative to an unshaped HE warhead), its design creates a more dispersed blast that causes damage over a much greater area on the interior and exterior of a warship.

While the P-15 Termit has frequently been cited in the West as having an alternate nuclear warhead, no operational variants appear to have actually been fitted with one. It is nevertheless plausible that such a feat could be accomplished however, due to the missile's large size; it is similar in dimensions and performance to the P-1 Strelka, which was definitely armed with nuclear warheads.

The first combat deployment of the P-15 Termit was in Operation "Anadyr" during the Cuban Missile Crisis, in which the Soviet Navy deployed 8 Komar class missile boats to escort arms shipments to Cuba. Though ultimately, no fire was exchanged between US and Soviet warships during this operation, and the Cuban Missile Crisis was resolved diplomatically.

It was in 1967 during the early days of the War of Attrition that the P-15 Termit first gained great fame (or infamy, depending on who you ask), when it earned the coveted distinction of being first missile to sink a ship in combat. This transpired on October 21st, when two Egyptian Komar class missile boats opened fire on the Israel Defense Forces (IDF) destroyer Eilat. The crew spotted the missiles and opened fire, not only mistaking them for aircraft, but also not having any training for engaging incoming missiles. Three of the four missiles launched hit the Eilat, causing catastrophic damage; she sank within hours, suffering 47 crew dead and a father 100 seriously injured, out of the crew of 199. This incident sparked a global arms race of anti-ship missiles and defenses against them which still rages to this day.

The P-15 made history once again in the 1971 Indo-Pakistani War, in which 11 were launched by the Indian Navy in two daring raids. The first of these was Operation Trident on December 5th, in which Indian Osa class missile boats sank the Pakistani destroyer Khaibar, the cargo ship Venus Challenger, and the minesweeper Muhafiz, as well as damaging the destroyer Shahjahan so badly that she was later written-off. The second raid was Operation Python, in which Indian missile boats used modified P-15s to bombard an oil refinery (the P-15 was not originally intended for attacking land targets) in Karachi, during which several tankers and cargo ships were also sunk. These raids were accomplished with no Indian casualties or ship losses, and with only one of 11 launched missiles malfunctioning.

The seemingly unstoppable winning streak of the P-15 Termit finally came to a halt in the 1973 Yom Kippur War, in which the Israelis turned the tables on Arab missile boat crews anticipating another easy victory. This time the IDF struck with a fleet of their own missile boats (the Sa'ar 2 class) armed with the Gabriel anti-ship missiles. Though the Gabriel was a smaller and shorter-range weapon than the P-15, its accuracy and maneuverability made it well-suited for attacking small watercraft; the same could not be said of the girthy P-15, which had been designed with engaging aircraft carriers and cruisers in mind. The IDF crews had also trained extensively for combat with and against missiles, and their vessels boasted chaff, jammers, and radar warning receivers. In the resulting Battle of Latakia, a numerically superior Arab missile boat force was virtually wiped-out, without a single vessel lost by the Israelis. This time, it was the limitations of anti-ship missiles that were demonstrated by the P-15.

There was also extensive usage of the P-15 Termit and its derivatives by both sides during the Iran-Iraq War. Both sides used them in their numerous attacks on each others warships, and upon civilian tankers steaming through the Persian Gulf. Iran also based coastal P-15 variants at the infamously narrow Strait of Hormuz, resulting in worldwide concern that these missiles could close the entire region to merchant traffic. The Iraqi Air Force was also able to adapt P-15 variants for use from aircraft during this conflict.

Numerous nations have operated the P-15 Termit over the years, to include Algeria, Angola, Azerbaijan, Bulgaria, Cameroon, China, Croatia, Cuba, Egypt, Ethiopia, Finland, India, Indonesia, Iran, Iraq, Libya, Morocco, North Korea, Poland, Romania, Russia, Somalia, Sri Lanka, Syria, Vietnam, Yemen, and Yugoslavia. Note that this does not include nations that have operated Chinese variants of the P-15 (rather than Russian variants).

Several operators have since retired the P-15 from service, including Finland, Germany (who inherited them from East Germany after unification), Poland, and South Yemen. Bangladesh is presently in the process of retiring their P-15 stocks. It is also likely that most other operators will retire their own P-15 stocks in the near future, as most of the remaining missiles are no doubt quite old and worn.

The P-15 Termit is no longer in production or development, although it is unclear exactly when production ended. The unit cost has not been published, although it would be presumably much lower than for contemporary missiles like the RGM-84 Harpoon. Though if one includes the cost of refurbishing and maintaining large stocks of missiles designed in the 1950s and mostly built in the 1960s, and considers the greater performance of most modern anti-ship missiles, the P-15 begins to lose its luster quickly.

Variants

Yak-1000: An experimental and ultimately unsuccessful fighter aircraft, the Yak-1000's design was re-purposed as a guided missile, resulting in the P-15 Termit. Did not enter production or service.

P-15: Basic production model, as described above. It was adopted in 1960. This missile has a maximum range of 35-40 km.

P-15M: Upgraded extended range model, with improved guidance and several incremental improvements. It was adopted in 1972. The P-15M has a maximum range of 80 km. Missile weight increased to 2 500 kg. Warhead weights 513 kg. This missile can be fitted with conventional or nuclear warhead.

P-15MC: Bulgarian-made P-15M, with an added electronic counter measures system.

P-20: Is an export variant. It has the P-15M's improved guidance, but not its extended range. Primarily intended for use by missile boats. It is also reportedly used by Rubezh (Western reporting name SSC-3 Styx) coastal defense missile system.

P-20K: Essentially a P-15M with a further improved guidance system.

P-20L: Submarine-launched version of the P-15U. Named the Ametist ("Amethyst") in Soviet service, and code-named SS-N-7 Starbright by the West.

P-20M: Surface-launched version of the P-20L with an MS-2A seeker.

P-21 used by Rubezh (Western reporting name SSC-3 Styx) coastal defense missile system. It is an export variant of the P-15M with an infrared-homing seeker head.

P-22 used by Rubezh coastal defense missile system: Another export variant of the P-15M with an infrared-homing seeker head.

P-27 used by Rubezh coastal defense missile system: Further development with an L-band radar.

HY-1 is a Chinese license-produced version of the P-15M. It is referred in the West as the Silkworm. The HY-1 was modernized numerous times and was supplied to a number of countries. It evolved into HY- and SY-series of missiles. Too many different versions exist to list them all here.

KN-1: North Korean missile derived from the P-15, with added technology from China's P-15 variants as well. It is sometimes designated as KN-01, or referred to as the Geum Seong-1.

FL-10 is reportedly an Iranian version, developed with China's assistance. Its production commenced in 1996.

Similar Weapons

Hs 293: German anti-ship cruise missile of World War 2, with a similar design to the P-15, but a radically different range and attack profile. Though much-celebrated as one of the first weapons of its type, the use of over 1 000 of them failed to sink more than about a dozen ships, at the cost of many bombers that launched and/or guided them. The lesson taught by the Hs 293 was that an AShM would only be viable in the open sea with a stand-off capability and a "fire-and-forget" guidance system.

MXY-7 Ohka: Japanese anti-ship cruise missile of World War 2, similar in size and performance to the P-15. However, the Ohka was rocket-powered, and manually guided by a pilot --- from *inside* the missile. Some 500 were launched in combat, but only sank 15 Allied vessels, all of which were only destroyers or auxiliary vessels.

P-1 Strelka: One of the first practical anti-ship missiles. Also called the KSShch ("Korabelny snaryad Shchuka", meaning "Pike Anti-Ship Munition"), the P-1 was similar to the P-15, but much larger, only launched from fleet warships, and armed with a nuclear warhead. All were retired between 1966 and 1977, and replaced on the ships that once used them with P-15 variants. It was code-named SS-N-1 Scrubber by the West.

P-5: Long-range ship and submarine launched cruise missile, with a conventional or nuclear warhead, and even a land attack capability. It is codenamed SS-N-3C Shaddock by the West, and though not formally named by the USSR, it was commonly called the "Pyatyorka" ("Fiver"; a reference to its stock number) in the Soviet Navy.

KS-1 Komet: Air-launched anti-ship cruise missile very similar in design and performance to the P-15 Termit. The KS-1 was launched only from the Tu-4 Bull (an unlicensed Soviet copy of the B-29 Superfortress) and the Tu-16 Badger bombers. Code-named AS-1 Kennel by the West. The KS-1 was retired in 1969.

S-2 Sopka: Land-launched version of the KS-1 Komet. Designated SSC-2b Samlet by the West. These were retired from the Soviet armed forces in 1980.

FKR-1: Nuclear-armed version of the S-2 Sopka. Code-named SSC-2a Salish by the West. They were presumably retired by 1980, along with the S-2.

K-10S: Air-launched cruise missile similar to the P-15 Termit, but with much greater speed and range, as well as a nuclear payload. Code-named AS-2 Kipper by the West. The K-10S entered service in 1960, and was withdrawn from service at an uncertain date.

MGM-1 Matador: US cruise missile similar in form and performance to the P-15 Termit, though not in function; this weapon relied on Manual Command to Line of Sight (MCLOS) guidance via radio command. It was armed with a nuclear warhead, and was launched from a trailer at a land target. The Matador was retired in 1962.

P-15 Termit
Anti-Ship Cruise Missile

P-15 Termit
Anti-Ship Cruise Missile