Osa-class

Summary

Description

The Project 205 "Moskit" missile boats, also known by their NATO reporting name "Osa," were a significant class of missile boats developed by the Soviet Navy in the late 1950s. These vessels served as a successor to the earlier Komar-class boats. Initially regarded as large torpedo boats until 1962, the Osa class became the most numerous class of missile boats ever built, with over 400 units produced between 1960 and 1973, including those built for export to Soviet allies.

The need for the Osa-class originated from the limitations of the Komar class, specifically their modest endurance, poor sea keeping, habitability constraints, and vulnerable wooden hulls. The Komar's armaments consisted of two P-15 Termit missiles and manually operated 25 mm guns, which proved inadequate for operational needs. To address these issues, the Osa class was designed as a larger, steel-hulled boat capable of mounting more sophisticated equipment and accommodating a larger crew. The boats featured a wide, low superstructure made of AMG alloys and a rounded and smooth deck designed for decontamination in nuclear scenarios.

Powered by three Zvezda M503 radial diesel engines, which delivered up to 15,000 horsepower in later variants, the Osa boats could reach speeds of about 40 knots. The ships were divided into two compartments housing a combination of main engines and generators and were outfitted with a control compartment in between. The arsenal included improved anti-aircraft capabilities with two AK-230 turrets equipped with 30 mm guns. Additionally, the offensive armament doubled from the Komars, featuring four P-15 Termit missiles in enclosed box-shaped launchers, improving effectiveness and over-the-horizon targeting.

Variants of the Osa-class included the original Project 205 ('Osa I') with box-shaped launcher for P-15 missiles, the Project 205U ('Osa II') with tube-shaped launchers, and the Project 205M with longer tubes for P-15M missiles among others. The Project 205's hull design also served as a basis for other Soviet fast attack and patrol boats.

In combat, the Osa-class saw action in the War of Attrition, Yom Kippur War, and Indo-Pakistani War of 1971. It proved effective for the Indian Navy during Operation Trident but faced losses in other conflicts, such as the Iran-Iraq War. Its shortcomings included limited effectiveness of missiles against ECM-equipped targets and the lack of medium-caliber guns for defense.

The Osa-class was succeeded by the Project 1241 Tarantul class corvette, which featured better electronics and armaments. Despite the advent of the Tarantul class, Osas remained widely in service until the turn of the 21st century.

Operators included the Soviet Navy and several international navies. Post-Soviet, one Osa boat remains in Azerbaijan, and two serve with the Latvian Navy. Other operators included numerous countries ranging from Algeria to Vietnam, some of which have undergone upgrades or utilize the boats for different roles, such as the Egyptian Navy's conversion of Finnish Tuima class ships for minelaying.

Technical specifications

Photo of Osa class