Frigates
A frigate is any of several types of warship, the term having been used for ships of various sizes and roles over the last few centuries.
Modern frigates are related to earlier frigates only by name. The term "frigate" was readopted during World War II by the Royal Navy to describe a new type of anti-submarine escort vessel that was larger than a corvette, but smaller than a destroyer. The frigate was introduced to remedy some of the shortcomings inherent in the corvette design: limited armament, a hull form not suited to open-ocean work, a single shaft which limited speed and maneuverability, and a lack of range.
The frigate was designed and built to the same mercantile construction standards as the corvette, allowing manufacture by yards unused to warship construction. The first frigates of the River class (1941) were essentially two sets of corvette machinery in one larger hull, armed with the latest Hedgehog anti-submarine weapon.
The frigate possessed less offensive firepower and speed than a destroyer, but such qualities were not required for anti-submarine warfare. Submarines were slow, and ASDIC sets did not operate effectively at speeds of over 20 knots. Rather, the frigate was an austere and weatherly vessel suitable for mass-construction and fitted with the latest innovations in anti-submarine warfare. As the frigate was intended purely for convoy duties, and not to deploy with the fleet, it had limited range and speed.
The contemporaneous German Flottenbegleiter ("fleet escorts"), also known as "F-Boats" were essentially frigates.They were based on a pre-war Oberkommando der Marine concept of vessels which could fill roles such as fast minesweeper, minelayer, merchant escort and anti-submarine vessel. Because of the Treaty of Versailles their displacement was officially limited to 600 tons, although in reality they exceeded this by about 100 tons. F-boats had two stacks and two 105 mm gun turrets. The design was flawed because of its narrow beam, sharp bow and unreliable high pressure steam turbines. F-boats were succeeded in operational duties by Type 35 and Elbing-class torpedo boats.
It was not until the Royal Navy's Bay class of 1944 that a British design bearing the name of frigate was produced for fleet use, although it still suffered from limited speed. These anti-aircraft frigates, built on incomplete Loch-class frigate hulls, were similar to the United States Navy's destroyer escorts (DE), although the latter had greater speed and offensive armament to better suit them to fleet deployments. American DEs serving in the British Royal Navy were rated as frigates, and British-influenced Tacoma-class frigates serving in the USN were classed as patrol frigates (PF).
The introduction of the surface-to-air missile after the Second World War made relatively small ships effective for anti-aircraft warfare: the "guided missile frigate." In the USN, these vessels were called "ocean escorts" and designated "DE" or "DEG" until 1975 - a holdover from the World War II destroyer escort or "DE". The British Royal Navy maintained the use of the term "frigate"; likewise, the French Navy refers to missile-equipped ship, up to cruiser-sized ships, by the name of "frigate", while smaller units are named aviso. Soviet Navy used the term "guard-ship".
From the 1950s to the 1970s, the USN commissioned ships classed as guided missile frigates which were actually anti-aircraft warfare cruisers built on destroyer-style hulls. Some of these ships—the Bainbridge-, Truxtun-, California- and Virginia- classes—were nuclear-powered. These were larger than any previous frigates and the use of the term '"frigate"' here is much more analogous to its original use. All such ships were reclassified as guided missile cruisers (CG/CGN) or, in the case of the smaller Farragut class, as guided missile destroyers (DDG) in 1975. The last of these particular frigates were struck from the Naval Vessel Register in the 1990s.
One of the most successful post-1945 designs was the British Leander-class frigate, which was used by several navies. Laid down in 1959, the Leanders were based on the previous Type 12 anti-submarine frigate but equipped for anti-aircraft use as well. They were used by the UK into the 1990s, at which point some were sold onto other navies. The Leander design, or improved versions of it, were licence-built for other navies.
Nearly all modern frigates are equipped with some form of offensive or defensive missiles, and as such are rated as guided-missile frigates (FFG). Improvements in surface-to-air missiles allow modern guided-missile frigates to form the core of many modern navies and to be used as a fleet defence platform, without the need for specialised anti-air warfare frigates.
The Royal Navy Type 61 Salisbury class were "air direction" frigates equipped to track aircraft. To this end they had reduced armament compared to the Type 41 Leopard-class air-defence frigates built on the same hull.
Multi-role frigates like MEKO 200, Anzac class frigate and Halifax class frigate are designed for navies needing warships deployed in a variety of situations that a general frigate class would not be able to fulfill and not requiring the need for deploying Destroyers.
At the opposite end of the spectrum, some frigates are specialised for anti-submarine warfare. Increasing submarine speeds towards the end of the Second World War greatly reduced the margin of speed superiority of frigate over submarine. The frigate could no longer be slow and powered by mercantile machinery and consequently postwar frigates, such as the Whitby class, were faster.
Such ships carry improved sonar equipment, such as the variable depth sonar or towed array, and specialised weapons such as torpedoes, forward-throwing weapons such as Limbo and missile-carried anti-submarine torpedoes such as ASROC or Ikara. Surface-to-air missiles such as Sea Sparrow and surface-to-surface missiles such as Exocet give them defensive and offensive capabilities. The Royal Navy's original Type 22 frigate is an example of a specialised anti-submarine warfare frigate.
Especially for anti-submarine warfare, most modern frigates have a landing deck and hangar aft to operate helicopters, eliminating the need for the frigate to close with unknown sub-surface threats, and using fast helicopters to attack nuclear submarines which may be faster than surface warships. For this task the helicopter is equipped with sensors such as sonobuoys, wire-mounted dipping sonar and magnetic anomaly detectors to identify possible threats, and torpedoes or depth-charges to attack them.
With their onboard radar helicopters can also be used to reconnoitre over-the-horizon targets and, if equipped with anti-ship missiles such as Penguin or Sea Skua, to attack them. The helicopter is also invaluable for search and rescue operation and has largely replaced the use of small boats or the jackstay rig for such duties as transferring personnel, mail and cargo between ships or to shore. With helicopters these tasks can be accomplished faster and less dangerously, and without the need for the frigate to slow down or change course.
Modern frigates are related to earlier frigates only by name. The term "frigate" was readopted during World War II by the Royal Navy to describe a new type of anti-submarine escort vessel that was larger than a corvette, but smaller than a destroyer. The frigate was introduced to remedy some of the shortcomings inherent in the corvette design: limited armament, a hull form not suited to open-ocean work, a single shaft which limited speed and maneuverability, and a lack of range.
The frigate was designed and built to the same mercantile construction standards as the corvette, allowing manufacture by yards unused to warship construction. The first frigates of the River class (1941) were essentially two sets of corvette machinery in one larger hull, armed with the latest Hedgehog anti-submarine weapon.
The frigate possessed less offensive firepower and speed than a destroyer, but such qualities were not required for anti-submarine warfare. Submarines were slow, and ASDIC sets did not operate effectively at speeds of over 20 knots. Rather, the frigate was an austere and weatherly vessel suitable for mass-construction and fitted with the latest innovations in anti-submarine warfare. As the frigate was intended purely for convoy duties, and not to deploy with the fleet, it had limited range and speed.
The contemporaneous German Flottenbegleiter ("fleet escorts"), also known as "F-Boats" were essentially frigates.They were based on a pre-war Oberkommando der Marine concept of vessels which could fill roles such as fast minesweeper, minelayer, merchant escort and anti-submarine vessel. Because of the Treaty of Versailles their displacement was officially limited to 600 tons, although in reality they exceeded this by about 100 tons. F-boats had two stacks and two 105 mm gun turrets. The design was flawed because of its narrow beam, sharp bow and unreliable high pressure steam turbines. F-boats were succeeded in operational duties by Type 35 and Elbing-class torpedo boats.
It was not until the Royal Navy's Bay class of 1944 that a British design bearing the name of frigate was produced for fleet use, although it still suffered from limited speed. These anti-aircraft frigates, built on incomplete Loch-class frigate hulls, were similar to the United States Navy's destroyer escorts (DE), although the latter had greater speed and offensive armament to better suit them to fleet deployments. American DEs serving in the British Royal Navy were rated as frigates, and British-influenced Tacoma-class frigates serving in the USN were classed as patrol frigates (PF).
The introduction of the surface-to-air missile after the Second World War made relatively small ships effective for anti-aircraft warfare: the "guided missile frigate." In the USN, these vessels were called "ocean escorts" and designated "DE" or "DEG" until 1975 - a holdover from the World War II destroyer escort or "DE". The British Royal Navy maintained the use of the term "frigate"; likewise, the French Navy refers to missile-equipped ship, up to cruiser-sized ships, by the name of "frigate", while smaller units are named aviso. Soviet Navy used the term "guard-ship".
From the 1950s to the 1970s, the USN commissioned ships classed as guided missile frigates which were actually anti-aircraft warfare cruisers built on destroyer-style hulls. Some of these ships—the Bainbridge-, Truxtun-, California- and Virginia- classes—were nuclear-powered. These were larger than any previous frigates and the use of the term '"frigate"' here is much more analogous to its original use. All such ships were reclassified as guided missile cruisers (CG/CGN) or, in the case of the smaller Farragut class, as guided missile destroyers (DDG) in 1975. The last of these particular frigates were struck from the Naval Vessel Register in the 1990s.
One of the most successful post-1945 designs was the British Leander-class frigate, which was used by several navies. Laid down in 1959, the Leanders were based on the previous Type 12 anti-submarine frigate but equipped for anti-aircraft use as well. They were used by the UK into the 1990s, at which point some were sold onto other navies. The Leander design, or improved versions of it, were licence-built for other navies.
Nearly all modern frigates are equipped with some form of offensive or defensive missiles, and as such are rated as guided-missile frigates (FFG). Improvements in surface-to-air missiles allow modern guided-missile frigates to form the core of many modern navies and to be used as a fleet defence platform, without the need for specialised anti-air warfare frigates.
The Royal Navy Type 61 Salisbury class were "air direction" frigates equipped to track aircraft. To this end they had reduced armament compared to the Type 41 Leopard-class air-defence frigates built on the same hull.
Multi-role frigates like MEKO 200, Anzac class frigate and Halifax class frigate are designed for navies needing warships deployed in a variety of situations that a general frigate class would not be able to fulfill and not requiring the need for deploying Destroyers.
At the opposite end of the spectrum, some frigates are specialised for anti-submarine warfare. Increasing submarine speeds towards the end of the Second World War greatly reduced the margin of speed superiority of frigate over submarine. The frigate could no longer be slow and powered by mercantile machinery and consequently postwar frigates, such as the Whitby class, were faster.
Such ships carry improved sonar equipment, such as the variable depth sonar or towed array, and specialised weapons such as torpedoes, forward-throwing weapons such as Limbo and missile-carried anti-submarine torpedoes such as ASROC or Ikara. Surface-to-air missiles such as Sea Sparrow and surface-to-surface missiles such as Exocet give them defensive and offensive capabilities. The Royal Navy's original Type 22 frigate is an example of a specialised anti-submarine warfare frigate.
Especially for anti-submarine warfare, most modern frigates have a landing deck and hangar aft to operate helicopters, eliminating the need for the frigate to close with unknown sub-surface threats, and using fast helicopters to attack nuclear submarines which may be faster than surface warships. For this task the helicopter is equipped with sensors such as sonobuoys, wire-mounted dipping sonar and magnetic anomaly detectors to identify possible threats, and torpedoes or depth-charges to attack them.
With their onboard radar helicopters can also be used to reconnoitre over-the-horizon targets and, if equipped with anti-ship missiles such as Penguin or Sea Skua, to attack them. The helicopter is also invaluable for search and rescue operation and has largely replaced the use of small boats or the jackstay rig for such duties as transferring personnel, mail and cargo between ships or to shore. With helicopters these tasks can be accomplished faster and less dangerously, and without the need for the frigate to slow down or change course.