Category Archives: Capability Analysis

Analyzing Specific Naval and Maritime Platforms

Corvettes Do Not Support Global Seapower

There is a growing belief in U.S. naval circles that aircraft carriers and higher-end U.S. surface combatants are becoming vulnerable to attacks by improved cruise missiles and targetable ballistic missiles such as the DF-21D. Proponents of this belief argue that corvette-sized vessels grouped in flotillas cost less, are more survivable than larger vessels and (somewhat darkly) suggest that U.S. national command authority would be less adverse to losing a few corvettes in combat than they would to the loss of a “capital ship” Arleigh Burke class destroyer. In reality, smaller ships have their own set of weaknesses that makes them no more effective than larger combatants. The littoral combatant ship (LCS) is capable of all of the peacetime and most of the wartime abilities of the corvette. Most importantly, the geography of 21st century seapower does not lend itself to low endurance vessels dependent upon isolated fixed bases for support. It may be useful to build and test a small flotilla of such craft as a proof of concept operation, but the U.S. should not build a large number of corvettes (and repeat the mistakes of the LCS program), until a full program of test and evaluation is complete. Even then, the U.S. should be wary of putting so much of its at-sea striking power in such a short-ranged, vulnerable class of ship.

DN-ST-93-05725Corvettes have their own “laundry list” of shortcomings that make them undesirable as a replacement for a large part of the current surface fleet. Past missile corvettes have been employed by less powerful navies as low-cost, short range coastal defense units. These craft enjoy interior lines of communication and supply, and are an ideal component to a coastal nation’s anti-access/area denial (A2AD) capability. U.S. corvette advocates however desire to use them in an offensive role on the high seas. Such an flotilla would be dependent on network information for both offensive and defensive operations. In the years since the First Gulf War in 1991, the U.S. has made it very clear to any of its potential opponents that it is very reliant on military networks to achieve its desired military objectives. No peer or near-peer opponent is likely to allow the U.S. unimpeded use of its military networks and will likely targets those systems in its own first attacks. Without network connectivity, corvette forces would be dependent on their own short-range sensors for targeting data and would need to move dangerously close to prospective targets in order to attack. The U.S. is still dependent on the 1970’s vintage Harpoon subsonic anti-ship cruise missile (ASCM) as the likely armament of a missile corvette. Longer range supersonic weapons would need to be developed and fielded in order to make the ship a “battle-worthy” opponent. Failure to do so would create another fiasco like the LCS where key mission components significantly lag behind the construction of the actual ship. Unlike higher-end U.S. combatants, corvettes do not have area defense weapons nor are their weapon systems self supporting. If attacked, rather than a networked defense, each corvette must individually engage incoming threats. Such actions, if uncoordinated and done in close proximity to other ships can have disastrous results. In the 1982 Falklands war, there were cases of ASCM’s decoyed away from one ship that suddenly engaged another without time for response. A corvette is also much more likely to be destroyed with all hands than a larger U.S. surface combatant if hit by even one medium-sized cruise missile. Each such corvette has a crew of between 35 and 40 highly trained personnel who would likely be lost. If the U.S. Navy really does value its well-trained personnel more highly than individual ships, it will not assign them to corvettes likely to be sunk. “They Were Expendable” makes for a good movie title, but U.S. naval personnel in the 21st century are not such a disposable commodity.

Supporters of the corvette claim that the ships can fulfill many peacetime duties including presence functions and training with allied naval forces. The LCS, which is already under construction and in the process of fleet introduction, is already capable of such activities. LCS is also a fully deployable warship capable of sustained operations at sea for at least 21 days. A force of corvettes however has only an 8-day sustainability at sea and would require a significant advanced base from which to resupply and refuel. If the recent behavior of even a close U.S. ally as Japan is any example, few nations would desire a large U.S. military presence necessary to support a large number of corvettes. The LCS can be supported through refueling and resupply at sea via underway replenishment. Since the LCS is already planned for procurement in large numbers, why duplicate its capability with another class of ship?

Finally, the geography of seapower as understood by maritime nations with global interests such as the United States does not support the use of such short-ranged vessels as corvettes. Such a nation must be ready to transfer large parts of its armed forces seamlessly over great distances. Relatively high-speed, long range naval units capable of global deployment are the best solution to the problem of geography. Corvettes can be moved from one part of the globe to another but neither with the speed nor cost effectiveness of larger platforms with better endurance. The fleet of a global power must be able to depart from one location, sail thousands of miles if necessary, arrive in theater and attain sea control without reliance on forward land bases which may be vulnerable or unavailable for use.

A small force of corvettes as a proof of concept test may be useful, but in the current constrained fiscal environment, the first priority of the Navy must remain high-endurance vessels capable of extended combat operations at sea without forward base support. A large force of corvettes cannot meet this requirement. If required in a wartime scenario, corvettes can be procured and rapidly fielded in large numbers. The U.S. is a maritime nation with an interest in protecting and securing what political scientist Barry Posen called the “global commons” of oceanic trade routes. Global power projection requires globally deployable naval units rather than regionally dependent corvettes.

Steve Wills is a retired surface warfare officer and a PhD student in military history at Ohio University. His focus areas are modern U.S. naval and military reorganization efforts and British naval strategy and policy from 1889-1941. He posts here at CIMSEC, and at under the pen name of “Lazarus”.

Philippine Navy Frigate Program: An OPV by Any Other Name?

By Armando J. Heredia

The Philippine Navy has unveiled bidding specifications to purchase it’s first new major surface combatant in several decades. Titled “Frigate Acquisition Program,” this key milestone of the Capability Upgrade Program will reorient the nation’s military from decades of COIN operations and enable a credible defense against conventionally-armed opponents.

090906-N-0120R-068A closer look at the program’s bid specifications along with missions that are likely to be met by the platform, reflects the balancing act between cost and capability that all naval forces must perform when seeking mid-to-low assets. Is it really a frigate that they’re looking for? Or is it more of a corvette? Or even an Offshore Patrol Vessel (OPV)?

It’s worth noting that at a functional view, the distinctions today between frigates, corvettes and OPVs are subtle; and in most cases, the label used is more about political expediency than clear-cut delineations about capabilities. For purposes of this article, an OPV leans towards enforcement or constabulary duties as opposed to being a dedicated combatant vessel, with a minimal weapons fit necessary to fulfill it’s function.

A Philippine Navy Desired Force Mix paper published in 2012 identified gaps in several operational specialties including Anti-Air Warfare (AAW) and Anti-Submarine Warfare (ASW); roles traditionally filled by frigates and corvettes. The bid specifications at a high level paint a picture of a multi-role combatant with embarked helicopter that meets both those capabilities, plus a moderate surface warfare punch.

However, a closer look at the requirements calls into question if the program is really seeking a frigate:

  • Perform Economic Zone Protection Roles
  • Operate up to Sea State 6
  • Operational Range of 4,500 nautical miles @ 15 knots
  • 30 Days Endurance
  • Minimum upper speed of 25 knots

Starting at the top, the Exclusive Economic Zone (EEZ) specification combined with high endurance and rough sea-state handling gives signals that we’re looking more at a patrol vessel for primary use. The contemporary history of spats with China over the resource-rich Shoals and the Spratlys is a stark reminder that asserting claims in the maritime space is one of the Philippine’s political drivers for modernization. Currently, the Navy has only two vessels capable of sustained operations to the edges of the EEZ; namely the newly acquired High-Endurance Cutters (WHEC) from the U.S. Coast Guard. It’s logical that follow-on ships would enhance those same patrol and presence operations.

The lower speed range (most combatants top out at 30+ knots), large operating radius, modest cruise rate and long endurance time reinforce the idea of patrol rather than dedicated offensive operations. While a specific propulsion type is not mentioned, one of the reasons the Philippines did not leverage wide availability of gas-turbine ships in the used defense market is a concern for their high fuel consumption rates. That may be explained in some part by the doubling of the Navy’s Petroleum, Oil & Lubricants (POL) expenditure; seeming to coincide with the initial operating year of the gas-powered Hamilton WHECs. While the cutters by themselves cannot be the sole cause, it’s a reminder that with new acquisitions comes a increased overhead – there are no free lunches. Gas-turbine plants are also a novelty, having been introduced to the Fleet only on the WHECs – and an older model to boot. Given all that, it’s likely that the winning bid will be diesel-based. This is also a characteristic of patrol vessels, prioritizing fuel efficiency and a greater operating range while trading off reduced speeds for sprints, evasive maneuvers and transits.

Other aspects to consider:

  • Embarked helicopter and rigid hull inflatable boat (RHIB) facilities, including full hangar space for the aviation asset
  • Accommodations for special warfare or other occupants
  • Selection of a 2D air search radar and Electro-Optical (EO) sensors
  • A quadruple Surface-to-Air (SAM) launcher with infrared or semi-active homing missiles (5km minimum range)
  • Two dual-box Surface-to-Surface Missile (SSM) Launchers (total of four missiles, 50 km minimum range)
  • 76mm main gun
  • One (1) secondary stabilized gun

Again, some subtle differences delineate this vessel’s requirements from a pure combat craft. Helos and RHIBs are common to both ship types – force multipliers that enable presence, intelligence-gathering and and if needed, kinetic reach well beyond the ship’s limits. Conversely, they can also be used for search-and-rescue (SAR) and law enforcement. A possible supporting indicator is whether the winning bid uses ramps versus davits. The latter method is more versatile and enables SAR operations in rougher seas that would swamp a ramp-equipped ship. The additional accommodations, while noted for special warfare detachments, can also double as holding areas for refugees, survivors or detainees.

When selecting a sensor suite for a frigate, there are no advantages to having a 2D radar versus a more capable 3D radar that facilitates, among other things, effective anti-air warfare. Coupled with the minimal SAM armament that is purely defensive in capability, this cannot be one of the ships meeting the AAW role. The under specification of the SSMs (eight missiles are nominally found on most warships) is another indicator of the balance between versatility and weapons fit, potentially indicating that deckspace is either at a premium or needs to be freed for other purposes. The 76mm main gun leverages operational and maintenance commonality, as the Oto-Melara is present on other ships in the fleet. It is also just about the largest caliber that can be found on patrol vessels. No explicit Close-In Weapons System, a staple in modern warfare against missile-equipped opponents, is another tell. Very rarely are OPVs armed with last-ditch defense systems, and their secondary gun is usually a slower-firing weapon in the 20-35mm range rather than high-speed multi-barrelled Phalanxes or GoalKeepers.

Of the eleven prospective bidders, what are some of the offerings that might fit? The tight budget requirement really drives baselines to be a small hull, likely accompanied by a custom sensor/weapons fit that may not tick all the boxes.

Navatia’s Avante 1800 is an excellent candidate, ticking and in most cases, exceeding the requirement checkboxes. South Korea could be sitting pretty, as the pending sale of FA-50 fighters could put them at the top of the list to leverage same-source efficiencies. But it will take a lot of corner-cutting to get Hyundai’s Incheon-class frigate down-specified to fit the bill. While not in the prospective bidders list, other close alternatives are BAE’s Amazonas-class OPV, and ST Marine’s Fearless baseline platform. Other alternatives may be immediately disqualified on the basis that they must be “proven vessels,” – i.e., previous successful sales of the platform in the past ten years.

Given the short period that has passed since publication of the technical specifications, it’s not surprising that the bidding deadline moved to the end of November, granting interested parties more time to build competitive proposals. Of all the hurdles they face, the one that may be most daunting is the projected total budget of roughly USD400 Million for both units plus integrated logistics support. The situation is further complicated by the notorious 2-Stage Bid Process that has derailed previous acquisition programs.

A term that will likely puzzle and frustrate the bid analysis is “Fitted for but not with” – meaning, “yes, we’d like to have Feature X, but if your bid doesn’t have it, it might still be okay and we might actually have the money for it but we can’t tell you right now.” It’s a very big symptom of the program’s tone of uncertainty. If no changes are issued to the technical specifications, then only pre-bid Q&A will enable prospective companies to tailor their offerings.

The program could quickly run out of steam if winning bids don’t emerge. If that happens, the bid process resets with accompanying waiting periods. Several factors are lining up that would make such delays to a successful signed contract fatal. For starters, the monies allocated will need to eventually be reset if not spent, requiring passage again through an already lengthy and onerous legislative process. President Benigno Aquino III’s term will end in 2016, and there is no guarantee that the following administration will be as supportive of military modernization. Finally, there is growing call for a rejection of purchases that are not addressing immediate security needs such as the Sabah and Zamboanga crises. Assuming a bid makes it past, they will still have to reckon with Stage 2, where potentially something as small as a documentation omission or error could force a reset back to the beginning as well.

To succeed, the Frigate Acquisition Program needs to move away from a minimums-only approach on technical specifications. A Request-for-Proposal that states minimums exclusively will beget minimums – driving the bidders to a cost-sensitive solution. By emphasizing what this platform really should excel at (i.e., surface warfare or AAW), this gives maneuvering room for the suppliers to build in additional selling points under the bottom line. This gives the Philippine Navy a solution that should satisfy cost limitations and deliver the most value.

Armando J. Heredia is a civilian observer of naval affairs. He is an IT Risk and Information Security practitioner, with a background in the defense and financial services industries. The views and opinions expressed in this article are those of the author, and do not necessarily represent the views of, and should not be attributed to, any particular nation’s government or related agency.

Offshore Patrol Vessel Missions in Wartime

clydeThe Offshore Patrol Vessel (OPV) is a contemporary ship category not easily understood; it is mostly lost in the larger debate to distinguish similar vessel types such as frigates and corvettes. For our purposes, the OPV is a ship leaning towards enforcement or constabulary duties as opposed to being a dedicated combatant vessel, with a minimal weapons fit necessary to fulfill it’s function.

What then to make of it’s functions in wartime operations? What kind of value can nations gain from OPVs in a conventional, non-nuclear shooting war? OPVs can deliver good value in such a crisis, even though they are not dedicated surface combatants. Much like any other application of platforms, the vessel’s capabilities must be matched up to the assigned mission.

These applications are more suitable for larger navies, where OPVs exist as a distinct ship type usually assigned to coast guard function, either as combatants or as law-enforcement/search-and-rescue assets. For smaller navies, the OPV might be considered a major combatant type equivalent to a guided missile destroyer or other capital fleet unit, thus relegating these missions to even smaller and lighter vessels such as patrol craft.

In general, use of OPVs frees up a navy’s dedicated surface combatants to conduct the tactical operations necessary to fulfill whatever strategic goals needing to be met. In addition, OPVs can supplement some of those combatant roles if properly equipped to do so.

Constabulary Duties and Coastal Patrol – under wartime conditions, the requirement to provide security for stretches of coastlines or critical areas is more valid than ever. Hostile Special Forces, Non-State Actors and a host of other threats can benefit from an unsecured shoreline. And as history points out, life doesn’t stop because of war. There will still be commercial and private traffic (albeit at reduced levels) requiring monitoring and law-enforcement/safety-at-sea activities. OPVs will excel at this function with their long endurance, excellent fuel-economy (thanks to the ubiquitous use of diesels) and if confronted by significant enemy forces, can call upon air support and shore batteries thanks to coastline proximity.

Search-and-Rescue (SAR) – as part of a conventional war, there will inevitably be fleet casualties. While immediate SAR upon conclusion of an engagement is both efficient and humanitarian, surviving fleet units may need to egress immediately in response to a current threat, or to transit elsewhere for another mission. OPVs with their excellent seakeeping, and equipped with small boats and rescue helicopters are perfectly suited to follow-up SAR missions.

Supplementary Naval Forces – some maritime nations have experimented with up-arming their coastal guard forces with front-line equivalent equipment – notably the US Coast Guard’s baseline of the Hamilton-class cutters during the Cold War to have Harpoon missiles, close-in defenses and the ability to operate anti-sub helicopters. While modern OPVs have less deck and internal volume margin to become a true multi-role combatant; it’s not a far stretch to equip them with basic Anti-Surface Missiles, defensive Anti-Air mounts, and potentially towed array sonar. Their speed-of-advance would not make them suitable assets for front-line strikes, but OPVs could supplement fleet units by taking on secondary but vital missions that could free up a guided missile frigate or corvette – for example, providing close escort for a secondary supply line convoy or troop transports. Other creative ways would be to use OPVs as pickets – with a decent sonar suite, the ships could “trawl” across likely areas of enemy sub activity, passing back contact information to Command-and-Control for possible investigation. Conversely, many OPVs have a helicopter pad and some ability to carry “mission packages” such as relief equipment. Instead of humanitarian supplies, place an ELINT module aboard and load up on aerial drones to gather ISR and expand a fleet’s MDA.

It is important to keep in mind that such investments, including any necessary upgrades to bring OPVs to fleet-unit status, is extremely capital-intensive. However, in a wartime setting, it is assumed that cost is secondary to achieving whatever military and political goals required to end the conflict on favorable terms. Using OPVs in such roles will also require some proof-of-concept during peacetime, where there is opportunity to experiment and discover what does work in the field.

Fleet commanders should remain aware of the limitations of this concept. For starters, OPVs are not fast enough, nor are they capable of sufficient self-defense such that they can be committed to a heavily contested battlespace. Skills such as anti-sub warfare are extremely perishable. Specialist detachments will need to be embarked to supplement regular crews depending upon mission and equipment assigned. Integrating OPV forces into annual fleet training exercises is a good step to ensure operational readiness. Where possible, OPVs will do best in missions that are in close proximity to friendly forces. Despite all these limitations, the value proposition to utilize OPVs in conventional war is compelling, and should be considered seriously should force structure and budget allow.

Juramentado is the pseudonym for Armando J. Heredia, a civilian observer of naval affairs. He is an IT Risk and Information Security practitioner, with a background in the defense and financial services industries. The views and opinions expressed in this article are those of the author, and do not necessarily represent the views of, and should not be attributed to, any particular nation’s government or related agency.

Corvette: What Is It And Why Does It Exist?

The question posed in the title is trivial but without an obvious answer. The term corvette originally appeared in 17th-century French Navy documents. It defined corvettes as simply ships smaller than frigates, a definition that has survived until today. This class of ship is defined only by size.
flower_class_corvetteDuring interwar periods in different countries similar ships were called sloops, gunboats, or avisos. At the outbreak of WWII, the name corvette was revived by the British Royal Navy for a class designed to meet a pressing need for cheap and mass produced ASW escorts. As a result, a design based on a whale catcher became probably the most famous corvette type, the Flower class, the hero of Nicholas Monserrat’s novel Cruel Sea.
In 2004, a team of NATO naval specialist worked on a paper entitled, Small Ship Design.  This document brought additional distinctions in ship classification and made an important difference between Offshore Patrol Vessels and Small Littoral Combatanst. The first optimizes its weight and volume for endurance, presence and low-cost, the latter for combat-related payload and survivability. It is important, however, to note that we observe many designs that we can call “hybrid”, either up-armed OPVs with some naval standards implemented to enhance survivability or lightly armed combatants sometimes classified as patrol corvettes or patrol frigates. The resulting designs can be better understood after a reading of D.K. Brown’s discussion of ship’s design philosophy in his book The Future British Surface Fleet: Options for Medium-sized Navies. The author describes the story of Type 23 Duke frigates, initially intended to be relatively small ships that could tow a sonar array:

“The ship envisaged was too expensive to be expendable, and yet was unable to defend itself. The whole concept was therefore philosophically “unstable,” and had to shrink to a cost level at which its loss could be accepted, or grow to a cost of over 100 million pounds in order to allow for some defensive armament.”

It seems that corvettes as opposed to OPV are dangerously close to above mentioned “unstable” zone. corvettes and other “flotilla” ships also suffer from attitudes driven by axioms of modern management. In peacetime, with only limited means available, we prioritize goals and focus on the seemingly more important “battle-force” rather than the “flotilla.” The latter falls into the “would be nice to have” category, but this changes in wartime. Vincent P. O’Hara, W. David Dickson, and Richard Worth in their book On Seas Contested illustrate wartime construction efforts during WWII made by major players by showing the number of ships built during the war, by category. This data, supplemented by a simple web search, and presented in a slightly different form makes visible how small combatants grow in number.

Why do corvettes exists at all? It seems appropriate to ask such a question if the whole class definition is based on size only. An attempt to make a generalization could be a statement that for the big navies of naval powers, corvettes fulfill some niche, specialized roles like coastal ASW, patrolling or even mine warfare, while for small navies or land powers they tend to be a capital ship. For a big navy they promise relatively low costs and hi numbers of hulls. Strict control of specifications and requirements as well as resigning from everything not related to the planned main function of the ship are essential to keep their costs within the budget. On an opposite side of spectrum, a small navy would be driven by the desire to install more powerful sensors and armament. Seakeeping and endurance could be of interest as well. The problem is that any efforts to turn these small combatants into multi-mission ships pushes them towards “unstable” zone of design.

The weakest point of corvettes seems to be their air-defense capabilit,y limited typically to self-defense. This means that at least in theory corvettes are rather easy to destroy by cruise missiles or even direct munitions dropped by aircraft. To overcome this limitation corvettes need to operate under the cover of battle-force or shore based defensive systems. They could also use tactics known from the Cold War’s “Outer Air Battle”, aiming to kill the shooter, not the arrow. Cruise missiles give corvettes disproportionate power to their size, but to use such weapons effectively, information superiority is a necessary and the best defense. Another problem that quickly emerges is the number of munitions at their disposal and how effective they are. Helicopters and/or armed UAVs are valuable assets for corvettes adding both to firepower and information superiority. Yet another road is to seek support from technology. One good example is the Swedish Visby corvette designed with the motto Invisible, not Invincible, another is the CAMM missile, which offers mid-course guidance independently from radar thus promising local area air defense for ships smaller than frigate. Or as already mentioned unmanned vehicles are another way technology can provide an edge.

The variety of tasks or functions flotilla ships like corvettes can fulfill is very large and quite often not anticipated before as shown by below excerpt from Wikipedia description of the Royal Australian Navy’s HMAS Bathurst: 

“The two main purposes the ships were intended for were minesweeping and anti-submarine escort. However, the corvettes found themselves performing a wide range of duties, including troop and supply transport, bombardment, assault landings support, survey and hydrography mapping, and providing aid to disabled ships.”

So what to do with a ship so broadly defined, surprisingly useful in wartime, and in permanent tension between value and performance? If we take a look once more again on Sir Julian Corbett typical forms of naval warfare…

“For clearness we may summarize the whole in tabulated analysis, thus:—

1. Methods of securing command:
(a) By obtaining a decision.
(b) By blockade.

2. Methods of disputing command:
(a) Principle of “the fleet in being.”
(b) Minor counter-attacks.

3. Methods of exercising command:
(a) Defence against invasion.
(b) Attack and defence of commerce.
(c) Attack, defence, and support of military expeditions.”

Corvettes can participate in all of these. It just depends on few factors like whether the navy possesses preponderance over the enemy, or is acting independently or as a part of coalition forces. A small navy facing a dominating enemy can still conduct minor counterattacks, but under the cover of an allied battle-force it can switch to attacking  or defense of commerce or a blockade. Even decisive battle is conceivable if the enemy fleet is an equally small peer navy. Although not really a homogenous class of ships, corvettes and similar small ships will most probably continue to be popular and in demand and will surprise us by their versatility.


Przemek Krajewski alias Viribus Unitis is a blogger In Poland.  His area of interest is the context, purpose, and structure of navies – and promoting discussion on these subjects in his country.