Worldwide Frigates and Corvettes

Corvettes and frigates are multi-purpose guided-missile warships, the former operate in coastal and maritime areas and the latter on the oceans. Modern surface combatants - which include cruisers, destroyers, frigates and corvettes - are the workhorses of the fleet. Corvettes and frigates play a dominant role in most navies. The term "Frigate" may be applied to ships with over 3,000 tons of displacement to as much as 7,500 tons. (By comparison, an Oliver Hazard Perry frigate displaces about 4,000 tons.) Corvettes are smaller, maneuverable, lightly armed warships (between the size of a patrol boat and a frigate) that various countries use for coastal duty.

Corvettes typically provide nearly all the striking and sensor power of a frigate in a smaller platform. The corvette is generally defined as a heavily-armed small surface combatant measuring 55 to 100 meters in length and displacing up to 500 to 2,500 tons. A distinguishing feature of the corvette is her capability for limited independent deployment, typically between 10 to 20 days, and usually equipped with self-defence capability against air and submarine threats. It is often also helicopter-capable - sometimes even affording her own hangar. Such craft can take on at least an ASM-armed helicopter at standoff ranges up to 13km.

It is difficult to establish a clear and fast distinction between frigates and corvettes, inasmuch as even the displacement cannot be used as a basis of classification. Ships which would be designated in one navy corvettes, are called frigates in another. A ship the size of a small frigate or large corvette, on the order of 2,500-3,000 tons, provides a good balance between payload and endurance. It can deploy reliably overseas while having enough room for acceptable crew facilities, and it is the smallest ship deemed capable of supporting a single medium-sized helicopter.

AMI forecast that between 2010 and 2030 the US market will make up 63% of the world's future spending on aircraft carriers and large expeditionary ships, 39% of the world's investment in cruisers and destroyers, 37% of world submarine spending, and 23% of the global market for frigates and corvettes. The US naval and maritime security market is expected to remain the largest in the world over the 20 years 2010-2030. A Coast Guard study in 2002 estimated that the projected global market for frigates, corvettes and off-shore patrol vessels over the 15 years 2002-2017 was $57 billion. The Another 2010 estimate of the market for corvettes over the ten years 2010-2020 pegged the value at up to $4.5 billion based on an average vessel unit price of around $215 million. The size of this potential market indicates that the corvette is still a vessel in high demand and the sheer versatility of these vessels is the secret of their appeal.

Optimum design is a relative subject because the issues of sustainment and cost play a significant role in the decision. In one analysis, LCS was shown to be the most combat-effective performer, but its cost detracted from its operational advantages. MILGEM is a medium size ship with high performance and lower cost, making her the most cost-effective candidate. Visby, on the other hand, has the lowest cost and because of its stealth can be as effective as others, but it was not nearly as sustainable.

There are at least 15 ship manufacturers globally providing a light frigate option of between 2,000 and 4,000 tons as of 2018. That is an awful lot of competition when the customers are ill defined. Let us look at some of those competitors for the Type 31 frigate: there is the French and Italian FREMM class; the Spanish Navantia F-105; the Danish StanFlex; the F-125 Baden-Württemberg class; and South Korea’s Incheon class, let alone the myriad cheaper platforms built by China and other far-eastern nations. Britain last exported a frigate over 40 years ago.