The world’s fleets of corvettes and frigates attract significant operational and market interest — an interest that exceeds their relative importance as naval ships types when measured by hull numbers or weights in today’s global fleets. This article provides a short review of international frigate and corvette programmes—future and present.
Frigate and Corvette Functions
Corvettes and frigates remain a focus of effort and investment for several reasons. First, the two types are the most numerous types of multi-mission surface combatants. That is, in contrast to patrol vessels, attack craft or other ship types optimised for a single primary mission, corvettes and frigates are typically designed to carry out missions in several naval domains – notably, surface warfare (ASuW), anti-air (AAW) and anti-missile warfare and anti-submarine warfare (ASW). Secondly, corvettes and more so frigates represent the largest and most capable surface platform – the “capital ships” – in many navies around the world. Lastly, as ships designed to operate either singly or in naval formations of many ship types, corvettes and frigates offer naval leaders wide options for employment, and in doing so challenge their commanders and crews to master the many facets of the naval art like almost no other type of naval ship.
This article provides a short review of international frigate and corvette programmes, drawing on naval market forecasts and other data from AMI International, a naval market consultancy that has served the industry globally for over 30 years. The article begins with overviews of new construction corvettes and frigates projected to enter service over the next 20 years, highlighting some trends and regional developments for each type. The article concludes with a brief look at the numbers of corvettes and frigates now in service, with some observations about regional patterns, ship design specifics (displacement) and average ages of the types.
Corvettes-Future and Present
The corvette fills an interesting space in the surface combatant market, as these types of ships share characteristics of both their smaller fast attack and patrol craft counterparts (size and hull features) and larger frigates (weapons and sensors). Corvettes and Offshore Patrol Vessels also have many design features in common.
AMI defines the corvette as fast (25 knots or better), well-armed ships that displace between 700 and 2000 tons. A corvette is generally not intended for extended ocean-going operations but have higher speed and therefore less endurance and range than OPV.
AMI forecasts the corvette market over the next 20 years as comprising 57 new hulls with a total acquisition value of US$12.9Bn. This makes the corvette one of the smaller subsegments of the global naval market, representing about one per cent of the 20-year future market for naval ships by value, and about two percent of the 20-year market by number of hulls.
The average value of new corvettes forecast to be acquired is about US$225M, with an average displacement of just over 1,500 tons full-load displacement (FLD). Countries acquiring new corvettes are generally mid-tier or smaller navies, where the affordability of the corvette compared to the frigate is an attractive aspect of the vessel type.
Corvettes by Country
Of the 15 countries projected to add new construction corvettes to their fleet by 2040, three are countries that were part of the former Soviet Union (Ukraine, Turkmenistan, Azerbaijan), while two others (Poland and Bulgaria) operate in seas on the flanks of the former USSR. Russia and Germany are the most prominent among “Tier I” navies with corvette programmes. Of note, AMI does not identify any new corvette programmes in China’s naval future, although as detailed below, the PRC is forecast to acquire 50 new frigates over two programmes in the next two decades.
Turkey stands out as country that has enjoyed some corvette export success with its indigenous MILGEM corvette design. AMI classifies Turkey’s 3000 ton modified MILGEM G design as a frigate, but MILGEM exports to Ukraine and Pakistan are based on the smaller (2,000 ton) original MILGEM corvette.
Corvettes historically have been primarily intended for ASW, tracing operational and design lineage back to convoy escort ships of World War II. However, in the post-Cold War era, corvettes have become more multi-mission platforms – “junior partners” to frigates in combined fleet operations, and capable of at least limited independent operations across the mission spectrum of ASW, AAW and ASUW. Of the 57 new corvettes in AMI’s market forecast, almost all are equipped with anti-surface missiles and guns as well as gun or missile based anti-air capabilities. Corvettes generally retain some ASW capability with sonars and ASW rockets or torpedoes.
The Global Inventory
AMI tracks a total of 332 operational corvettes in its inventory of serving naval ships – the Existing Ships Data Base. With only 57 new corvettes forecasted to be built in the coming 20 years, the existing corvette inventory can only get smaller between now and 2040. This will increase the incentives for navies to invest in modernisation to keep their corvettes in service and capable of meeting mission requirements, since they will not be replaced on a one-for-one basis by new build programmes now in place or projected.
Among the 332 corvettes, in service, the age distribution breaks down as follows. Notably, over half the world’s fleet of corvettes are 15 years or older, further signalling that the corvette segment will get smaller through 2040, when most of those older hulls will have been retired.
Frigates: Future and Present
AMI defines the frigate as a medium-sized surface combatant (between 2,000 and 5,000 tons) that is either optimised for one specific role (ASW or AAW) or is a general purpose combatant that has fewer systems and capabilities than a destroyer. A frigate is generally the smallest surface combatant that can conduct extended blue-water missions in a high-threat environment.
AMI forecasts the frigate market over the next 20 years as made up of 368 new hulls with a total acquisition value of US$183.2Bn. While larger than the corvette market by a factor of 15, the frigate segments still represents only 15 per cent of the world’s future naval ships by aggregate market value, and roughly the same percentage by hull numbers.
By comparison, the future submarine market of fewer hulls (300) makes up about one third of the total naval market (about US$400Bn) over 20 years by aggregate value. Looking at future frigate procurements by region, the Asia-Pacific leads, with 15 countries accounting for 20 of 57 programmes (35 per cent) and 167 of 368 new hulls (45 per cent). Next is the NATO (excluding the US) and Non NATO Europe (Finland and Sweden) region with 11 countries and 15 programmes projected to build 73 new frigates (20 per cent).
Frigate Numbers
AMI global forecasts for future frigate acquisitions are US$495M per ship in average cost, and just over 3,800 tons FLD in average displacement. Regional averages for the Asia- Pacific and Euro regions are shown here, reflecting slightly larger frigates in the AP region (4,100 tons compared to the Euro zone (3,900) and a lower average acquisition cost in the Asia-Pacific region (about US$400M per hull compared to just over US$500M per hull in Europe). The later difference reflects the heavy weight of Chinese ships in the A-P region (50 of the 167), for which actual acquisition costs, while unknown, are estimated to be lower than for frigates built in Europe.
As for frigates currently operating around the world, AMI tracks 575 hulls now in service. Of those, 298 (just over 50 per cent). Using an estimated average service life of 30 years, about 200 frigate hulls are expected to be retired by 2040. With 368 new hulls under construction, this indicated many nations are growing their frigate fleets and are building at above replacement rate. This trend is especially true in the Asia Pacific region, where China is projected to build 50 new 4,500 ton frigates over the coming two decades. Japan’s frigate program will see 22 new hulls of the MOGAMI class join the JMSDF over the same period, while three different Indian frigate programs account for 17 new ships of the type.
Conclusion
The corvette and frigate as types in the naval market appear to be on different courses. Corvettes in service are aging at a rate far beyond what new programmes will replace, indicating that the type, while still present, will shrink further in importance as a component on most fleet structures over the coming two decades. In contrast, frigate construction is robust and growing, both among navies that have long relied on the type as the most numerous surface combatant in their fleets (in Europe and some navies in the Asia-Pacific region such as Japan and Australia), and among navies whose force structures overall are growing in number and capability. China is the foremost example of the later type of “frigate growth” market, but others in the region include India, Indonesia and Malaysia.