Frigates vs. Corvettes: What’s the Difference?
In the navies of the world, regardless of size or firepower, every warship plays a specific role on the battlefield. Frigates and corvettes, though smaller in size, are equally important and widely used by navies worldwide, highlighting the delicate balance between specialized vessels within naval forces.
Each warship is unique in its design features and specific role on the battlefield, performing multiple functions within its capabilities. As an essential component of modern naval fleets, these ships play a vital role in ensuring maritime security, projecting power, and protecting strategic interests. Understanding the similarities and differences between these vessels is crucial for comprehending the specific strategies of naval forces.
Origins and History
The term “frigate” has a long history. It was initially associated with 16th-century Spanish galleys, 17th-century Dunkirk privateers, and Dutch naval warships armed with fewer than 40 cannons. It wasn’t until after the Seven Years’ War that the term began to refer to a small, heavily armed warship.
During World War II, Britain named its small escort vessels “frigates” to protect convoys from submarine threats. In contrast, the US Navy took thirty years to adopt the term “frigate” to refer to escort vessels larger than destroyers, and only unified its use with most other navies after 1975. Currently, “frigate” is a common term for small and medium-sized warships in navies worldwide, encompassing anti-submarine warfare, air defense, aircraft guidance, and other general missions.
In the age of sailing ships, the “corvette” was one of several single-deck warships closely associated with sailing ships. The French Navy first used the term “frigate” in the 1670s, and over the following decades, frigates steadily increased in size, eventually evolving into vessels capable of carrying 20 cannons.
The US Navy initially referred to frigates as sailing ships, while the British Navy adopted the term in the 1830s to describe a small, sixth-class vessel, slightly larger than a sailing ship. With the rise of steam power in the mid-19th century, frigates gradually faded from the battlefield, with some being converted to support gunboats during colonial expeditions. However, during World War II, frigates regained their vitality as small anti-submarine vessels escorting ships in the Atlantic, eventually evolving into the modern surface warships we know today.
Design Features
While classic sailing frigates, renowned for their important role in the Napoleonic Wars, were characterized by their boxy hull structure, modern frigates have evolved to be larger and incorporate more complex design features.
The German Navy’s “Baden-Württemberg” frigate is a prime example; it is currently the world’s largest frigate. This powerful vessel boasts a concealed hull and superstructure design, measuring 149.6 meters in length, 18.8 meters in beam, and displacing 7,200 tons. The Russian Navy’s “Admiral Gorshkov” class frigates are also among the most powerful frigates. These corvettes are 130 meters long, 16 meters wide, and have a draft of 16 meters. They are massive in size and possess excellent performance. These ships boast an impressive range of over 4,000 nautical miles and a displacement of 4,500 tons, giving them a powerful deterrent presence on the high seas.
Classic Sailing Corvette
Light corvettes are vessels of a lower class than corvettes, and their size far exceeds that of patrol boats. Modern light corvettes employ aerodynamic hull designs to increase speed, and their displacement typically ranges from 500 to 2,000 tons. The Köln is one of the newest members of this class, scheduled to enter service in 2025, and is the sixth Braunschweig-class light corvette in the German Navy. The Köln is 89.12 meters long, 3.28 meters wide, has a draft of 3.4 meters, and a displacement of 1,840 tons.
The Role of Corvettes as Warships
Initially, corvettes served as reconnaissance ships for the fleet, participating in mercenary raids, patrols, and transporting information and important figures. However, with the development of these warships, their roles have also changed. Modern frigates now perform patrol missions, protecting not only other fleet vessels but also merchant ships and amphibious expeditionary forces.
The emergence of missile frigates and anti-submarine frigates has further enhanced the importance of these warships on the battlefield. Modern frigates now play a broader role, actively participating in a variety of missions, especially in anti-submarine warfare.
Corvettes play a crucial role in modern naval warfare, demonstrating their versatility and effectiveness, particularly in intelligence, surveillance, and reconnaissance (ISR) missions. Beyond their vital role as reserve vessels in key operational scenarios, Corvettes excel in numerous other missions.
They play a vital role in escort missions, ensuring the security of critical assets; participating in coastal patrols to maintain coastal security; and actively engaging in humanitarian assistance and disaster relief efforts. Corvettess have also proven their value in smaller-scale conflicts, showcasing their flexibility and adaptability. Furthermore, they play a key role in flag-raising ceremonies, projecting naval presence, and conducting diplomatic activities in strategic areas.
Weaponry
Given their increasing importance on the battlefield, Corvettess solidify their advantage with a diverse arsenal designed specifically for their role. This arsenal includes advanced defensive systems such as anti-ship missiles, anti-aircraft missiles, naval guns, and torpedoes. Some frigates are also equipped with close-in weapon systems (CIWS), anti-submarine warfare (ASW) capabilities, and electronic warfare (EW) systems, enhancing their adaptability and survivability on the modern battlefield.
For example, the Italian Navy’s newest FREMM-class multipurpose frigate, the Spartaco Cergaat, is equipped with an impressive array of weaponry, including state-of-the-art anti-submarine warfare equipment such as the Thales 4110CL bow sonar and the Thales 4249 (CAPTAS 4) submarine detection system, as well as an advanced integrated electronic warfare system (IEWS).
Advanced Defense Systems
Depending on their specific missions, modern Corvettess are equipped with advanced shipborne weaponry, including small and medium-caliber naval guns, anti-submarine weapons, and ship-to-ship and ship-to-air missiles.
Furthermore, some ships are capable of carrying small or medium-sized anti-submarine attack helicopters. For example, the French Navy’s Gowin-class corvettes are equipped with a weapon system that includes anti-ship missiles, towed guns, self-defense systems, 12.7mm machine guns, 20mm naval guns, 76mm naval guns, and electronic warfare systems.
Electronic Warfare and Sensors
Corvettes significantly enhance a fleet’s battlefield combat capabilities through the integration of advanced technologies. These modern vessels are equipped with sophisticated sensor systems, such as radar, advanced communication systems, integrated command and control systems, and advanced navigation systems. The US Navy’s upcoming Constellation-class multi-purpose guided-missile frigates are a prime example of this technological advancement.
These ships are expected to be equipped with numerous advanced components, including the Aegis-10 main combat management system, the Raytheon AN/SPY-6(V)3 radar, and the Enterprise-class Air Surveillance Radar (EASR). Furthermore, these frigates will also be equipped with lightweight mobile sonar, anti-submarine warfare systems, variable-depth sonar (VDS), and other advanced systems.
Electronic warfare and sensors are key elements of the corvette’s operational framework, enhancing its situational awareness, self-defense capabilities, and overall mission effectiveness.
This complex integration of technologies includes advanced communication systems, a precise Global Positioning System (GPS), inertial navigation systems, countermeasures, advanced radar and sensors, and electronic countermeasures and support measures.
The fifth Navante 2200-class Corvette, being built for the Royal Saudi Navy, is scheduled for delivery in 2024. This ship is equipped with advanced weapon systems, including a 76mm Leonardo rapid-fire cannon, four 12.7mm machine guns, a 30mm machine gun, surface-to-air missiles and surface-to-ship missiles, torpedoes, and decoy launchers.
Stealth Performance
The integration of stealth technology significantly reduces radar cross-section, thereby enhancing the survivability and mission success rate of naval vessels. Frigates performing anti-submarine warfare, air defense, maritime patrol, surveillance, and escort missions benefit from advanced stealth technology.
The performance enhancement is attributed to the integration of a range of advanced functions, including reduced radar cross-section, radiation and signature management, reduced thermal infrared signature, and reduced acoustic signature. These features collectively enhance the effectiveness and survivability of corvettes in modern naval warfare scenarios.
Electronic Warfare and Sensors
In addition to advanced weaponry, light corvettes are equipped with advanced stealth systems, a key element ensuring their operational effectiveness in complex maritime environments.
The Russian Navy’s “Stereguru”-class light corvettes are a prime example of this capability. This class of ships employs advanced stealth design to minimize radar, acoustic, and infrared interference.
The ship is expected to be equipped with numerous advanced components, including the Aegis 10 main combat management system, Raytheon’s AN/SPY-6(V)3 radar, and Enterprise-class Air Surveillance Radar (EASR). In addition, these frigates will also be equipped with lightweight mobile sonar, anti-submarine warfare systems, variable depth sonar (VDS), and other advanced systems.
Electronic warfare and sensors are at the heart of the Corvettes’ operational framework, enhancing their situational awareness, self-defense capabilities, and overall mission effectiveness.
This complex integration of technologies encompasses advanced communication systems, precise Global Positioning System (GPS) and inertial navigation systems, countermeasures, advanced radars and sensors, and electronic countermeasures and support measures.
The fifth Navantia Avante 2200-class Corvette, being built for the Royal Saudi Navy, is scheduled for delivery in 2024. This ship is equipped with advanced weapon systems, including a 76mm Leonardo rapid-fire cannon, four 12.7mm machine guns, a 30mm machine gun, surface-to-air missiles and surface-to-ship missiles, torpedoes, and decoy launchers. Stealth Performance
The integration of stealth technology ensures a reduced radar cross-section, thereby enhancing the ship’s survivability and mission success rate. These corvettes, whose missions include anti-submarine warfare, air defense, maritime patrol, surveillance, and escort, benefit from advanced stealth technology.
Furthermore, integrated advanced features further enhance the performance of these ships, including reduced radar cross-section, radiation and signature management, reduced thermal infrared signature, and reduced acoustic signature. These characteristics collectively improve the corvette’s effectiveness and survivability in modern naval warfare.
Electronic Warfare and Sensors
In addition to advanced weaponry, light corvettes are equipped with sophisticated stealth technology, which is crucial for ensuring operational effectiveness in complex maritime environments.
The Russian Navy’s “Guardian”-class corvettes are a prime example of this capability. This class of ships employs advanced stealth design to minimize radar, acoustic, infrared, and magnetic signatures. The strategic integration of this stealth technology significantly reduces the radar signature of ships while minimizing their acoustic, infrared, magnetic, and optical signatures, fully demonstrating the comprehensive considerations in the stealth design of these warships.
Speed and Maneuverability
During World War II, frigates demonstrated cruising speeds of 20 knots. Since then, frigates have continued to evolve, making significant progress in modern naval warfare and possessing more powerful performance. Thanks to advanced propulsion systems, modern frigates can achieve higher speeds and greater maneuverability, with specific speeds and maneuverability depending on the ship type and purpose.
The Indian Navy’s Shivalik-class multipurpose stealth frigates can reach a top speed of 32 knots. The three Shivalik-class frigates currently in service achieve this speed thanks to the combined power of two Pielstick 16 PA6 STC diesel engines and two General Electric LM2500+ turboprop engines, with a total output of 47,370 horsepower (35,320 kilowatts).
Corvettes are smaller and more agile, generally more maneuverable than corvettes, but their speed is affected by a variety of factors. The Royal Norwegian Navy’s Skød-class Corvettes are a prime example of high-speed Corvettes. These 47.5-meter-long frigates are powered by four gas turbines, enabling them to reach speeds of up to 60 knots in calm waters. The Skød-class is one of the fastest ships in its class, demonstrating the agility and speed of modern corvette design.
Crew and Operations
The number of crew members required to operate a frigate or Corvettes depends on the ship’s class, design, mission, and performance. Factors influencing crew size include the complexity of the ship’s systems, the diversity of missions that can be performed, and the degree of automation integrated into the design.
Unlike traditional warships, modern frigates typically have a higher degree of automation, thus reducing crew requirements. Typically, a modern frigate has a crew of approximately 120 to 200, which contributes to its efficient operation on the battlefield.
Modern Frigates
Similar to frigates, the crew size required to operate a Corvette depends on its design and operational requirements. The Adavr-class Corvettes are one of the largest Corvettes currently in service with the Algerian Navy, measuring 120 meters in length and typically requiring a crew of 120. This giant vessel, built by a Chinese shipyard, is 14.4 meters wide, has a draft of 3.87 meters, and a full-load displacement of approximately 2,880 tons.
Cost and Maintenance
Due to differences in size, technology, and functionality, frigates (which outperform Corvettes) require significantly more investment in construction and maintenance. The German Navy’s Sachsen-class frigates (the last commissioned in 2006) are among the most expensive in their class, with a total cost of $2.37 billion for the three ships. Similarly, the Japan Maritime Self-Defense Force’s (JMSDF) first Mogami-class destroyer, recently commissioned, is estimated to have cost approximately 50 billion yen (about $452.7 million).
Corvettes also require substantial investment due to their complex design, advanced technology, and weaponry, although they are generally less expensive than frigates. A prime example is the Indian Navy’s anti-submarine frigate INS Kavaratti, commissioned in 2020. This ship is one of four Kamorta-class frigates built under Project 28 (the Kamorta class), with a total cost of $263 million.
Fleet Size
Navies worldwide are expanding their frigate fleets to defend their borders. The latest Global Firepower Index shows China leading with 43 frigates, followed closely by its neighbor, Taiwan, with 22.
South Korea and Turkey rank third and fourth, respectively, with 18 and 16 frigates. It’s worth noting that this list does not include ships currently under construction, such as the US Navy’s Constellation-class multi-purpose guided-missile frigates.
On the other hand, Corvettes are not the mainstay of naval fleets worldwide. However, the presence of the Russian Navy is significant globally. According to the Global Firepower Index, the Russian surface fleet leads with 86 Corvettes.
China and the United States follow closely behind, with 72 and 22 Corvettes, respectively, ranking second and third. Indonesia and India rank fourth and fifth, respectively, with 21 and 19 Corvettes.
