| P-70 Ametist (NATO reporting name: SS-N-7 'Starbright') | |
|---|---|
 | |
| Type | Anti-ship missile |
| Place of origin | Soviet Union |
| Service history | |
| In service | 1967-1992 |
| Used by | Soviet Union,Russia,India,North Korea (unconfirmed) |
| Production history | |
| Designer | Vladimir Chelomey |
| Designed | 1958 - 1968 |
| Manufacturer | NPO Mashinostroyeniye |
| Produced | 1966 - 1987 |
| No. built | 631 |
| Specifications | |
| Mass | 3,500 kg (7,700 lb) |
| Length | 7 m (23 ft) |
| Warhead | 4G66 HEAT Warhead or 200 kt nuclear |
| Warhead weight | 1,000 kg (2,200 lb) |
| Propellant | Solid fuel |
Operational range | 65 km (35 nmi) |
| Boost time | 7 seconds (tube exit to main stage) |
| Maximum depth | 30 m (98 ft) |
| Maximum speed | Mach 1.0 |
Guidance system | Inertial guidance, terminalactive radar homing |
Launch platform | Charlie-I &Papa classSSGNs |
TheP-70Ametist (NATO reporting name:SS-N-7 Starbright,GRAU designation4K66;Russian:П-70 «Аметист» 'Amethyst') was ananti-ship missile carried by Soviet and IndianProject 670 submarines, as well as the SovietProject 661 Anchar. It was soon succeeded by theP-120 Malakhit(SS-N-9 'Siren').
Fielded on June 3 1968, it was the first anti-ship missile system in the world to be launched from a submerged submarine. From 1968 to 1987, a total of 631 missiles were built.
TheP-5 Pyatyorka(SS-N-3 Shaddock) missile required theProject 659 submarines carrying them to stay surfaced after firing to send mid-flight guidance updates. This made submarines very vulnerable to enemy attack, so in the 1960s the Soviets started working on a new missile that could be fired whilst submerged, and a submarine would carry it. These became theP-120 Malakhit andProject 670 submarine.
However, problems with the engines of the P-120 Malakhit forced the Soviets to design a sub-launched missile based on theP-15M Termit(SS-N-2C 'Styx') as a stopgap measure for the first batch of Charlie submarines. This became the P-20L, later renamed the P-70 Ametist.
The P-15M was fitted with anL bandactive radar homing sensor and a newradar altimeter both developed for the P-120, but there was no room for a datalink in the smaller P-15M. Folding wings were added to reduce the size of the missile, and the missile could be launched at a maximum depth of 30 m (98 ft).
The short range of the P-70 meant it could rely on inertial navigation and radar-homing, and as such did not need mid-course updates from a radar on the submarine. Consequently, along with the addition of the radar-altimeter (which allowed for a much lower cruise altitude than previous missiles), the novel sub-surface launch capability meant that reaction time for surface targets was minimal.
As a result, the ability to deploy in littoral and close-range combat scenarios without necessitating exposure of the launching submarine more than made up for its lack of range compared to the P-5.
The P-70 went into service with the Soviet Navy on the first Project 670, on June 3, 1968.[1] About 200 were produced.
India leased the"Chakra" Project 670 submarine from January 1988 to 1992, to gain experience of operating a nuclear submarine.
