Project 205 Moskit/Osa I-class guided missile boats: Deadly Mosquito, Punch-Packing Wasp

[Sweepdown 146]

Hello and welcome. This suggestion thread covers the Project 205 Moskit (mosquito), or as NATO calls them, the Osa-class (Osa=wasp). This particular thread focuses on the Osa-I variant (the earlier one).

 

BRIEF DESCRIPTION

Not to be confused with (god forbid) the 9K33 Osa anti-air missile system, the Project 205 Moskit class, known to NATO as the Osa-class (Osa-I and Osa-II) are the archetypical Soviet missile boat- fast and heavily armed for their size, but also fragile and only of moderate seaworthiness. With over 400+ completed across all variants over a time period of 1960-1973, they are the most numerous missile boat class ever built. 

 

HISTORY AND DESCRIPTION

The predecessor of the Osa-I class was the Komar-class missile boats, which were designated Project 183R in the Soviet Navy. While they were good at what they are supposed to do- which is to be cheap, efficient platforms for anti-ship missiles- and even managed the very first anti-ship missile kill when a bunch of Egyptian-operated ones sank INS Eliat (formerly Z-class HMS Zealous), they had many problems.

Among them, they still had a wooden hull, their radar set not having FCS whatsoever, laughable defensive armament of only two 25mm manually-operated anti-air guns aimed with only a simple optical sight, they cannot be equipped with the newer P-15U missile (80km range compared to the 40km of the original) without dangerously compromising their seaworthiness, their crew-only 17 men- was not enough to optimally use all systems onboard, their endurance, seaworthiness and habitability were at best modest, and their missile box was vulnerable to wave damage. As a result, the Soviets decided to build a new missile boat class to remedy these problems.

The result of their endeavor was the Project 205 Moskit/Osa-I class. These ships had 4x the mass of the previous Komar-class, and a 28-men complement. The hull was made of steel, while the superstructure was made of lighter AMG alloy. The deck was continuous (flush), with smooth and rounded edges to ease washing off in case of nuclear contamination (as the Soviets were expecting to fight in a nuclear war).

Power was provided by three Zvezda M503 7-bank 42-cylinder maritime diesel radial engines providing 4000hp each (for a combined total of 12000hp). These allowed the Osa-I to sail up to 38,5 knots, and sail up to 1800 nautical miles (3300km) at a speed of 14 knots (or 800 nautical miles (1500km) at 30 knots and 500 nautical miles (930km) at 35 knots). There was also three diesel generators to power the ship's electrics- two engines and one generator were placed in the forward engine room while the third engine shared the aft engine room with the other two generators. Between the two engine rooms was a control room.

 

The Osa-I class had two AK-230 turrets that served as their CIWS/defensive armament; one was placed fore while the other was placed aft, behind the missile boxes (yes, the same ones on the Mikhail Kutuzov in game). These fired at 2000rpm (1000rpm/barrel) and had an effective range of 2.5km. These were intended for air defense; while they can be used against surface targets, the Osa-I is intended to fire its missiles then GTFO instead of sticking around. The turrets were controlled by an MR-104 Rys (Drum Tilt) radar mounted on a high platform aft of the superstructure.

The main offensive armament of the Osa-I class were four P-15 Termit/SS-N-2 Styx anti-ship missiles, carried in four enclosed armored boxes to prevent weather damage. Since this thread focuses on the earlier Osa-I and not the Osa-II, the P-15s equipped on these are the earlier 40km version. The guidance for these missiles were provided by a MR-331 Rangout (Top Bow) radar and a Nikhro-RRM (Square Tie) ESM/IFF that even allowed the Osa to fire at targets over the horizon that were stupid/forgetful/foolhardy enough to turn on their radar.

 

These missile boats were popular items on the export market, and were bought by anyone who were buying weapons from the Soviets- China, Egypt, Syria, India, Poland, Finland, Vietnam, Yugoslavia, and many others. In particular, China licence-built around 120 boats as the Type 021-class missile boat, which has its own variants and are armed with different weapons including C-704 missiles later on.

Of note are the Osa-I class boats in service with the Syrian, Egyptian and Indian service. The Syrian and Egyptian Osa-I class (accompanied by their direct predecessor, the Komar-class) boats duelled with four Israeli Sa'ar 3 boats (along with one Sa'ar 4), in the very first duel of missile boats ever seen anywhere. While the P-15s on the Komar and Osa-I had twice the range of the Gabriel Mk.2 missiles on the Sa'ar boats, Israel was able to reduce their effectiveness by using chaff and jamming (ECM) to the point that none of the Israeli boats were hit, and the Syrian/Egyptian boats were sometimes unable to escape when their engines malfunctioned. Closing in was not a good idea either, as the 76mm Otobreda cannons on the Israeli missile boats were more than capable of making mincemeat out of the Osa-I boats- as one Syrian Osa-I discovered the hard way when it pulled a Notser (aka beaching itself) on shallow waters and was sunk by cannon fire.

 

India, however, got far more success out of the Osa's than the two Arab states. They were first offered by the Soviets in 1964, but the Indians were not interested at the time. However, after the 1965 Indo-Pakistani War, Britain (who at the time had been the Indian Navy's largest supplier) refused to transfer more modern equipment to India, and as a result the Indians turned to the Soviet Union. In 1968, Pakistan was also offered the boats with associated infrastructure, but they wanted larger vessels and so turned the offer down. After India examined the performance of Egyptian missile boats during the 6-Day War, India finally agreed to sign an agreement purchasing 8 boats from the USSR in 1969, commissioning them into its navy in 1971 as the Vidyut-class, just a few months before the outbreak of the 1971 Indo-Pakistani War.

The crowning moment of the Indian boats, and arguably of the Osa-I class as a whole, is Operation Trident, which happened on December 4 1971, a day after the hostilities broke out. Three Vidyut-class missile boats, supported by two Indian Arnala-class ships (Petyan III-class anti-submarine corvettes/frigates), and a fleet tanker, closed to 250nmi (460km) Karachi under the command of Babru Bhan Yadav, staying there during the day to evade Pakistani Air Force surveillance during daytime. As the PAF didn't have night-bombing capabilities, they attacked at nighttime. The Indian missile boats achieved total surprise on the attack, managing to sink PNS Khaibar (HMS Cadiz, Battle-class, which is already in the game), MV Venus Challenger (at the time carrying ammo for the Pakistani Navy- the ship exploded), and PNS Muhafiz (Adjutant-class minesweeper). The attack also damaged PNS Shah Jahan (HMS Charity, C-Class) so badly that the vessel was deemed irreparable and was scrapped after the war. In addition, the Karachi fuel tanks were hit by a missile and burned, completely destroying them and causing a fuel shortage. This, and the follow up Operation Python three days later, caused the Indians to secure a de facto naval blockade on Karachi and severely demoralized the Pakistani Navy. India celebrates Operation Trident annually on 4th December as the Navy Day.

 

The successor of the Osa-class boats are the Tarantul-class corvettes, or Project 1241. The earliest versions of these had the same armament of four P-15s (though these were the 80km variant instead of the 40km variant used on the Osa-I), but had far better defensive armament- with a single AK-176 76mm automatic gun turret, in addition to two AK-630 six-barreled Gatling guns, Fasta-N SA-N-5/Strela-2 missile launcher and two PK-16 decoy launchers. However, there were fewer Tarantuls built so the Osa continued service in several nations through the 21st century.

 

IN WAR THUNDER

A pretty-much-mandatory addition for the Soviet coastal naval tree once we hit missiles; it would be a travesty to not have one of the most iconic missile boat classes in history for them. The Osa-I class can be foldered with the Osa-II class, with the latter obviously having a higher BR because its missiles have better range.

The AK-230 systems already exist onboard the Mikhail Kutuzov, and as a result that part shouldn't be too hard- only the radar system is different. The big enigma is the P-15 missiles; these are among the first successful missiles on the market, and while the Nettuno missile on the Saetta boat in the Italian tree is already in the game, the Nettuno is beam-riding and thus must be locked on until impact, which the Styx doesn't have to (the guidance variants being IR-homing, active-radar-homing, and autopilot (inertia-guidance), none of which involve keeping the missile lock on target).

 

SPECIFICATIONS

Type	Fast attack craft
Displacement	Osa I 171.5 (with M-504B – 184) tons standard 209 (with M-504B – 226) tons full load
Length	38.6 m (127 ft)
Beam	7.64 m (25.1 ft)
Draught	1.73 m (5.7 ft) (with M-504B – 1.84 m (6.0 ft))
Installed power	3 × 4,000 hp (3.0 MW) M-503G diesel engines (205)
Propulsion	3 shafts
Speed	38.5 knots (71.3 km/h) (M-503G)
Range	1,800 nmi (3,300 km) at 14 knots (26 km/h), 800 nmi (1,500 km) at 30 knots (56 km/h), 500 nmi (930 km) at 35 knots (65 km/h)
Endurance	5 days
Complement	28 (4 officers) (Osa I)
Sensors and processing systems	MR-331 Rangout (Square Tie) radar Klyon fire-control system for P-15 Termit Nickel IFF MR-104 Rys (Drum Tilt) fire-control radar for AK-230 ARP-58SV radio direction finder
Electronic warfare & decoys	Nikhrom-RRM IFF/ESM
Armament	2 × AK-230 twin 30 mm CIWS (2,000 rounds) 4 × P-15 Termit (SS-N-2 Styx) anti-ship missiles

 

(Note that this is copy-pasted from Wikipedia, with the Osa-II data removed since it isn't the variant discussed in this thread).

This one is from weaponsystems.net

 

 

PICTURES

A drawing of the Osa I-class. To differentiate them from the Osa-II, look for the missile tubes- the Osa-II's missile tubes are more tubular in shape.

An Osa-I class underway. The SS-N-2's fire-control radar is visible here, but not the rear AK-230 mount.

Another drawing for the Osa-II class

A front-view of the Osa-I class. Note the AK-230 CIWS and box-shaped SS-N-2 missile containers.

 

SOURCES

https://en.wikipedia.org/wiki/Osa-class_missile_boat
http://russianships.info/eng/warfareboats/project_205.htm

https://weaponsystems.net/system/982-Project+205+Moskit+class

https://www.globalsecurity.org/military/world/russia/205-specs.htm

 

 

[Miki_Hoshii 2,449]

Open for discussion.

[Milocat 4,848]

+1, would be a good addition to see.

[Kingtiez@live 606]

+1, since the US and Italy has smaller boats with missiles, this would be a great addition.

[CommissarDmitry 1]

Yeah… we really needs heavy anti ship missiles. Now the boats are almost useless when against destroyers.

[D4RKO_ 1]

totalmente necesaria e impresindible seria esta lancha lanza misiles...tenemos en los equipos rivales EE.UU la Douglas, y en italia a la saetta....y los que usamos la flota sovietica????como podemos contrarrestar si estamos de desigualdad????....por favor la nesecitamos U.R.G.E.N.T.E !!!!!!!!!

[D4RKO_ 1]

perdon soy nuevo por aqui......desconozco la trascendencia de los temas de los foros .....le llegan a los creadores de warthunder los pedidos de la comunidad????por ejemplo este tema lo ven ellos???

[csla1972 849]

+1

I remember them from movie The detached mission where these boats was used in role of enemies in final battle scene.

 

Edited January 30, 2023 by csla1972