It’s Corvette Week at CIMSEC

And Chuck Hill has a nice piece to start us off with, asking (and answering) the most basic question- just what is a corvette?

Classification of surface warships as cruisers, destroyers, frigates, or corvettes, has become like pornography. There are no generally accepted definitions, but “I know it when I see it”–except that everyone sees it a little differently.

Since this is “Corvette Week” what are we really talking about?

(Note: unless otherwise specified, lengths are over all and displacements are full load)

My Combat Fleets of the World, 16th Edition, which I have used here extensively for reference, defines Corvettes as, “Surface Combatants of less than 1,500 tons but more than 1,000 full load displacement–essentially, fourth rate surface combatants.”  but goes on to note that “…the designation as used here essentially refers to smaller frigates and does not correspond to the European concept of corvettes as any warship larger than a patrol craft but smaller than a frigate.” I feel to confine the definition within a 500 ton range is too restrictive. in fact it would have excluded the Castle class corvettes of WWII as too large, and other corvettes as too small.

I’ll just note that in our Navy, typically the smallest surface combatant we’ve built in peacetime is the Frigate or (as designated prior to 1975) the Destroyer Escort.

Our Navy currently is pretty well stocked with Destroyers, with some 62 of the excellent DDG-51 class in service. But our Frigates of the FFG-7 class are nearing the ends of their service lives. The LCS is being built, but since day one, Big Navy has denied the LCS is a replacement for the Frigate.

And to a great extent, that’s true. Our Frigates, while always general purpose warships, have been optimized for the open ocean Anti-Submarine Warfare (ASW)  role.

With the collapse of the Soviet Union, the blue water ASW mission has declined greatly. But there is still a pressing need for a numerous class of warships to fulfill missions that don’t require the capability of a multi-billion dollar DDG-51.

Is there a place for a low-end corvette combatant in our Navy? What roles and missions would it perform? Where is it likely to serve? How should it be armed?

Hopefully, the Corvette Week series at CIMSEC will provide answers to those questions.

Musings on Frigates

So, CDR Salamander had a post on shipbuilding estimates  for the DoN going forward. Of course, you can’t have a post like that and not have frigates come up in the conversation. So I thought I’d muse on frigates for a bit.

The term “frigate” has been around navies for a long, long time. But the meaning of frigate has tended to drift a bit.

Back in the age of sail, or Nelsonian navy times, if you said a ship was a frigate, it tended to have a very precise meaning. First, it was  a ship. That is, it was a vessel with three masts (not two, not four, ONLY three), and each was square rigged. Further, the ship had at least 20 guns. Finally, the guns were installed on a single gun deck, not multiple gun decks like ships of the line, or on the main deck like smaller vessels. Frigates were used for a wide variety of missions. They conducted convoy escort, they raided enemy commerce, conducted reconnaissance as the eyes of a fleet, and supported the line of battle, usually by repeating signals to those ships that couldn’t see the flagship. They were strong enough to defeat anything smaller than them, and fast enough to outrun anyone stronger than them.  They were the “utility infielders” of the sailing navies. Indeed, the first warships built specifically for our fledgling US Navy were Six Frigates.

But as wooden ships and iron men came to be replaced by steel hulled ships in the age of steam, traditional ship classifications tended to fall into disuse.  While ships of the line (of battle) eventually became battleships, the term cruiser tended to be used for those ships that operated well away from the fleet, either for scouting, or for commerce raiding.  In our own navy, the term frigate pretty much disappeared for the first half of the 20th century.

During World War II, the British named escort ships bigger than corvettes, but smaller than destroyers “frigates.” In our own Navy, for the most part, we called them “Destroyer Escorts” but a small class of ships was built (by the Maritime Administration, not the Navy) to commercial standards, and called frigates.

After World War II, the Navy built a series of fast carrier task force escorts as replacements for the World War II era fleet destroyers. The need for speed, endurance, large sensor suites and seakeeping drove the size of these ships up greatly from their WWII forebears. The increase in size and cost stunned a lot of people, and rather than calling them destroyers, they were at first called “destroyer leaders*” but eventually, the term frigate for a fast carrier task force escort came into being. These ships were still numbered in the “DL/DLG” category, even if the name was changed.  But unlike frigates of old, these ships were not intended to operate independently. Rather, they were tied into the carrier task force, both by their sensors, and (eventually) by an early electronic network, the Navy Tactical Data System (which, we’ll get around to writing that post eventually).

On the lower end of the combatant scale, the Navy continued building destroyer escorts, but over the years, changed the name to “Ocean Escorts” even while still numbering their hulls in the “DE” category.  These ships were tailored to providing anti-submarine escort to convoys and shipping in the open ocean, and were not suitable for inclusion in the fast carrier task force.

For reasons known but to the SecNav and CNO at the time, in 1975, the Navy changed the naming conventions. Ocean Escorts/Destroyer Escorts were now to be called “Frigates.”  All the ships formerly numbered in the “DE” series suddenly were numbered in the “FF” series. Their hull numbers didn’t change.

The fast task force escorts suddenly needed to be redesignated, as it was silly for an 11,000 ton nuclear powered guided missile escort to share the same category as a 3000 ton anti-sub ship. Accordingly, those ships in the DL/DLG classes were redesignated either cruisers or destroyers, based rather arbitrarily on their displacement.

*Ironically, Destroyer Leaders of the inter-war period were numbered in the DD series, not their own.