OPC, Design for Wartime, Build for Peacetime

As noted in the post “GAO Responds to Fleet Mix Studies, Part 1, The Report,” the Department of Homeland Security “Cutter Study” raised the possibility of an austerely equipped Offshore Patrol Cutter (OPC) possibly deleting some equipment or capabilities of the ship as currently planned including:

  • Sensitive Compartmentalized Information Facility (now referred to as the Ship’s Signals Exploitation Space or SSES)
  • Air Search and Fire Control Radars
  • Electronic Warfare Support Measures
  • Berthing space (114 instead of 122)
  • Weapons suite (e.g., 25mm gun instead of 57mm)

This got me to thinking. What do these ships really need, both for their peacetime functions and for possible wartime roles? I hope the Department’s suggestion presages a return to CNA (Center for Naval Analysis) to do a more formal evaluation of the effects of these changes. Until then, I’ll venture some comments on these proposed deletions, then go on to talk about how the ships might be equipped first for war, then for peace.

  • Ship’s Signals Exploitation Space (SSES): This seems to be mostly for drug enforcement, but with obvious Defense Operations implications. It’s possibly useful for fisheries and SAR as well. While we never used to have a formal SSES, cutters did frequently feel compelled to generate their own. Intel is a great force multiplier, so I would not cast aside the capability casually. Still we are hearing there is already far more intel available for drug enforcement than there are units to act on it, so it’s loss might not be that significant.
  • Air Search and Fire Control Radars: While the CG has managed to live without these on the 210s, the air-search and/or fire-control radars seems likely to be needed to exploit the Unmanned Air Systems (UAS) the CG hopes to use, because they can provide a substitute for the eyes in the cockpit required to “see and avoid” other traffic. They may also be necessary to fully exploit the range of the embarked helicopter.
  • Electronic Warfare Support Measures: The ships probably could do without the ESM (and associated decoys) in peacetime, unless it is feeding info into the SSES.
  • Berthing space (114 instead of 122): I would not expect simply reducing berthing (but not crew size) to save much money, and it would unnecessarily reduce future flexibility. If these ships are used for cadet cruises, they are likely to need all the berthing that might be available.
  • Weapons suite (e.g., 25mm gun instead of 57mm): This might be doable, but there is still a concern for the peacetime requirement inherent in the Ports, Waterways, and Coastal Security mission of being able to stop a ship being used for a terrorist act, as illustrated in the Concept of Operations, section 3.3.4 (pdf, accessible here). I’m unconvinced that the 57 mm is much of an improvement over the 25 mm, while other systems with a smaller footprint, might be more effective and, if adopted, might extend this capability to more numerous and more readily available vessels than the few cutters mounting 57 or 76 mm guns.

Designed for Peace or War?:

I’ve always felt Cutters built since World War II have been neither fish nor fowl. They have been much more expensive to build than ships built to commercial standards because they are in many ways warships. In other ways, not a lot of consideration seemed to have been given to their war time roles, which meant that they had only limited potential as warships.

It is probably be counter-productive to equip cutters as fully armed warships. Not only does it significantly raise their operating costs, it would make them less welcome in many areas where cutters are accepted, but US Navy ships are viewed with suspicion.

My own feeling is that the large patrol cutters should be adaptable as warships. Ships take a long time to build. Cutters constitute a naval reserve that can be brought on line much quicker that new ships can be built. But they would need to be upgraded significantly before they would be “battle-worthy” in the more demanding scenarios. That is probably as it should be, but making that transition not only possible, but as quick and effective as possible is a worthwhile objective. Additionally extra weight moment margins mean the ships will also be more adaptable to changes in peacetime Coast Guard missions over the long term.

The Offshore Patrol Cutter Concept of Operations (which can be accessed here) actually seems to agree at least to some degree, but does not include the proposed capabilities of the fully armed version of the cutter other than some non-specific references to upgrades in section 3.3.5.2.

The WMSM will have the ability to install additional equipment to augment its capabilities if it is required to conduct operations in higher threat environments in support of national security objectives.“–Executive Summary, Concept of Operations.

Later, in defining Defense Operations there is this statement, “The WMSM will operate in a low, multi-threat environment as defined below. The cutter shall be designed for, but not delivered with, the equipment and configuration to allow for operations in higher threat environments.

(This may mean little more than that the ships are equipped for, but not with Phalanx.)

Planning for additional weapons in case of a potential major naval conflict was done in the past, to some degree, with the 210s and 270 WMECs. Space and weight was identified for additional weapons. Fortunately it was never necessary to see if those plans were realistic. I would like to see this concept taken further, beginning by designing a true warship, at least through the preliminary design stage, but then choosing to equip it only with those weapons that either serve a peacetime purpose, or are so complex that they could not be added in a yard period of some reasonable period. This would have the additional advantage of making the design potentially attractive to both the Navy and foreign governments seeking to purchase similar vessels for their navies under foreign military sales. It is likely the shipyard might see this as an advantage as well.

Wartime Outfit:

Here I am referring to a full conversion to a dedicated fighting ship. It is unlikely to be necessary unless there is a protracted conventional conflict with a near peer adversary. As unlikely as that may seem, it is the sole justification for much of the Defense Department, where many times the Coast Guard’s entire budget is invested annually. In lower level conflicts it may be sufficient to “come as you are” or make selected upgrades.

In considering the OPC, the exact size has not been decided, but it seems likely it will be 2,500 to 3,500 tons. If so, it should not be asking too much to expect a design capable of carrying a weight of weapons and aircraft at least equal to the weight of weapons carried by the much smaller 255 foot cutters, when they were first built during WWII. This included two twin 5″/38s (85.4 tons), two quad 40mm mounts (20.7 tons), hedgehog (12.8 tons), six K-Guns, depth charges, and racks (approx. 25 tons), and four 20mm guns. All together, roughly 140 to 150 tons. This is intended to be a conservative approach because there are certainly additional weights not included below, but these ships really ought to be able to carry considerably more weapons than the 255s.

How could we equip a cutter with a similar load of modern weapons and aircraft? Here one possibility.

  • H-60           11 tons
  • UAS  (weight unknown, but estimate an estimate probably on the high side)
    4   tons
  • Mk 38 mod 2 25 mm guns (x2) (estimate on the high side)                                                             3   tons
  • AN/SQR-20 Multi-Function Towed Array (MFTA)(Thales CAPTAS 4)                                              20.6 tons
  • Mk 32 Surface Vessel Torpedo Tubes (SVTT) (two triple and 12 torpedoes)                                    5.2 tons
  • CIWS (2) (Phalanx, SeaRAM, or Mk 49 RAM launcher, probably Mk 49 fwd, SeaRAM aft)                     14   tons
  • 5″/62 Mk45                                                                                                                                   33   tons
  • Mk 57 or Strike length Mk 41 Guided Missile Vertical Launch Systems (8 cells)                             33.6 tons

Total                  124.4 tons

The helicopter and UAS are expected already. In wartime the helicopter would probably be a Navy variant. The UAS might also be armed. The ship would need space for storage of weapons and sono-buoys. These spaces could have other uses in peacetime, like locker rooms for boarding parties or meeting/rec rooms.

The Mk38 mod 2 is very versatile and given the right projectile it might be an effective ship stopper.

A submarine threat is reemerging. The multi-function towed array is the essential ASW sensor. It can operate in both active and passive modes. In the passive mode, it is an over the horizon sensor that can be used in full EMCON Alpha against an enemy vessel also exercising EMCON.  OPCs equipped with towed arrays and MH-60R helicopters, operated in groups, could be deadly hunter-killers.

The torpedo tubes provide an urgent attack capability against a sub that is unexpectedly detected at close range.

Providing a Mk 49 RAM launcher forward and a SeaRAM aft would provide immediate launch facilities for up to 32 missiles that could engage either air or surface threats and counter a saturation anti-ship cruise missile attack. The Mk 49 would integrate with the ships firecontrol and air-search radars, while the SeaRAM would provide automatic autonomous engagement and cover any gaps in radar coverage of the primary systems.

The 5″ Mk45 matches nicely the Concept of Operations direction that the OPC may be included in Expeditionary Strike Groups. These groups’ reason for existence is amphibious assault both by air and over the beach. The 5″ is still the primary Naval Surface Fire Support (NSFS) weapon and even after the 155mm Advanced Gun System is deployed on the DDG-1000, there will still be a place for the 5″ to take out the probably numerous targets close to the landing area, allowing the very limited number of Zumwalt DDGs (three) to conserve its limited ammunition for more difficult targets. A 5″Mk 45, even without advanced ammunition, positioned 10,000 yard off the beach, can hit targets on the beach (assuming it is a straight line) over a more than 19 mile wide front. That is as large as any of the five beaches at Normandy. Additionally Mk48 Gun Weapons System planned for the OPC already works with the 5″.

It might be assumed that the guided missile vertical launch system tubes are out of place here, but they have become the Swiss army knife of naval weapons, being useful for anti-submarine, anti-surface, and land attack missions as well as air defense. Four Evolved Sea Sparrow Missiles (RIM-162 ESSM) can be launched from each tube so that eight tubes can launch up to 32 missiles. Strike length VLS like the Mk 41 (and here) and Mk 57 can also launch Vertical Launch ASROC, Harpoon, and Tomahawk. If equipped for cooperative engagement, missiles launched from a cutter could be controlled by Aegis equipped ships. The Mk41 VLS would normally be mounted between the gun and the bridge, but the Mk 57 launchers can be added to the side of superstructure or the hangar in groups of four. There are also lighter VLS systems such as the Mk48 and Mk 56 (lots of pictures here) that are US made but not currently in US service.

Peacetime Outfit:

For its actual construction the ship will need much less. It might have only the following:

  • H-60
  • UAS
  • Mk 38mod2 25 mm guns

The type of guns the ship is equipped with in peacetime is still an open question. The Ports, Waterways, and Coastal Security (PWCS) scenario,  3.3.4.2, requires the OPC to protect a “Maritime Critical Infrastructure/Key Resources (MCI/KR)” by “neutralizing” a ship. The size of the ship is not clear, nor is what constitutes effectively neutralizing it, but we know it may not be easy to stop or sink a vessel. If the 25 mm can be proven to effectively stop a ship, the service may choose to risk limiting weapons to these heavy machine guns. But if they do so, the cutter will have to come inside the range of likely improvise armaments that might equip such a terrorist ship, with attendant risk that the cutter’s weapons might be knocked out and the cutter might be still be unable to stop the ship. The 57 mm offers greater range, but may still lack the power to stop a larger vessel. All gun options present the problem of collateral damage from shots that miss or pass through the target. Light weight torpedoes modified to hit a surface ship’s propellers might be an option. There are also missile options that might be considered, that are lighter and less maintenance intensive that a medium caliber gun and its associated supporting equipment.

Really this mission should not depend on the presence of a WMSL or WMSM, that is unlikely to be available when the need arises. These ships are usually either far from the port or in “Charlie” status. We need another way of addressing this mission.

File:US Navy 101027-N-8913A-252 Rounds from a Mk-15 Phalanx Close-in Weapon System (CIWS) from the guided-missile destroyer USS Mitscher (DDG 57) impact.jpg

Phalanx might still have a place in the peacetime outfit, if it is found to be an effective ship stopper. (Oct. 27, 2010) Rounds from a Mk-15 Phalanx Close-in Weapon System (CIWS) from the guided-missile destroyer USS Mitscher (DDG 57) impact the ex-USNS Saturn during a sinking exercise. Mitscher and other ships assigned to the George H.W. Bush Carrier Strike Group fired live ammunition at Saturn. (U.S. Navy photo by Mass Communication Specialist Seaman Leonard Adams/Released) More photos here. (It took quite a bit to sink this ship.)

Trade-offs, Options, and Alternatives:

In choosing equipment for the cutters, it might be desirable to include selective upgrades for limited number of ships, rather than building them all the same–AN/SQR-20 Multi-Function Towed Array (MFTA)(Thales CAPTAS 4)–Ships expected to do drug enforcement, looking for self propelled semi-submersibles, might have towed array sonars for drug enforcement while those expected to do fisheries in the Pacific might not.

In the paper exercise of designing both a warship and a peacetime cutter, there are some tradeoffs available that might make it easier.

  • Berthing–In designing the fully armed version, it should be acceptable that wartime berthing will be more crowded than the peacetime standard. During WWII crew complements sometimes doubled compared to those planned in peacetime. The crews will be willing to make sacrifices.
  • AMIO–The current OPC specs call for the ability to shelter and feed 500 additional people on the weather decks. That is about 40 tons of addition topside weight. The fully armed version would likely have to trade this capability for the weapons outlined above.
  • Range/Endurance–The minimum range requirement for the OPC is 7,500 nautical miles. Up to 9,500 is desired. As long as the ship retained a range of about 4,500 miles–typical for American surface warships–trading some fuel space for magazine space on the fully armed version might be an option.

There is also the possibility of including plans for alternative combinations of systems on the fully armed cutter, so that when a need arises the decision maker can pick and choose from a portfolio of possibilities to match the need. Additional missile launch tubes might replace the gun. Littoral Combat Ship mission modules or Mk141 Harpoon launchers might replace the VLS.

46 thoughts on “OPC, Design for Wartime, Build for Peacetime

  1. The stripped down version still needs the ROSAM’s. Otherwise it won’t have the close-in capability to operate in an FPCON-C/D environment. The reality of optimal crewing is that you don’t have the bodies to man the machine gun crews. WMSL (6 mounts) requires 19 people – 3 per gun plus control officer. A ROSAM replacement would only require 9 – 6 operators, a reload crew of 2, and a control officer. Probably more importantly, with the ability to swap mount control between consoles, you could likely run a GQ3 with 3 members – 2 operators and a control officer. The WMSM would realize the same manning savings.

    Ships are most at risk in a harbor transit as they don’t have sea room to maneuver and target are engaged closely. Also, the ROSAM’s smaller caliber mitigate the risk of collateral damage.

    Also, if we are looking at a peace time deck gun, I’d prefer the Bushmaster MK 46. It comes at 30MM but can be upgraded quickly to 40mm until a full war time conversion can be completed.

    • My thinking was that if you have Mk38s arranged so that at least two bear in virtually every direction, you don’t really need .50 cal. I would also think you would want to load them with armor piercing, discarding sabot rounds which are non-explosive and .50 cal in size but might penetrate both the hull of a ship and an engine block.

      My understanding is that the Mk38 mod2 can also be upgraded to 30 and 40 mm.

      • I’d still want a crew-served .50 cal or two just in case something goes wrong with the Mk38.

      • The fact that we can mount four .50 cals doesn’t necessarily mean we would want to man all four even at GQ, particularly if it meant that we would have to increase the size of the crew.

        Crew served .50s are pretty nearly useless as anti-aircraft weapons so that is not really a consideration.

        For surface targets, short of being surrounded by an Iranian swarm, we are unlikely to have more than one target at a time. If we mount all four guns, two crews will normally be able to shift from side to side as necessary.

  2. We should think twice before deleting any comms capability. I was on a ship that could not be involved in certain operating areas because of lack of secure comms. No one at HQ would sponser (pay for) the retrofit.

  3. Just think how much more effective the Coast Guard would be as a Coast Guard if its cruising cutters did not have to double as reserve frigates! If this additional cutter capability is really, really, necessary, then the Navy should pay for it. But what conceivable wartime scenario requires it, especially now that the Navy is building a huge fleet of Littoral Combat Ships?

    • I think we are going to have to disagree on that one, because my feeling is that it is better to have one vessel serving in the Coast Guard that is available for war time contingencies than it is to have two ships, one Navy and one less capable Coast Guard Cutter.

      Don’t think you can call a planned 55 LCS a huge fleet, since even after they are built, total numbers of Navy vessels will be down near historic lows.

      over 230 Navy ships were involved in the Cuban missile crisis:
      http://www.history.navy.mil/faqs/faq90-3.htm
      Plus Coast Guard and allies.

    • “especially now that the Navy is building a huge fleet of Littoral Combat Ships?”

      Really?? So far none of the planned mission modules even work! Without them the LCS is a big overpriced under armed patrol boat, not to mention all the corrosion problems these new ships are already experiencing. I predict short service lives for both LCS types and I would be surprised if they build the total number planned. JMO

    • The problem is that the USCG cutters are already considered part of the National Fleet and therefore WILL be used as adjunct warships now and in wartime.

      Not my idea but Undersecretary Work’s

      And YES the USN should pay for additional warfighting capabilities in USCGC, now try to find how small that is in current budgets?~~

      IMHO a full LCS program will NOT happen, then what next?

      • After the first 24 LCS are built, the USN may be in the market for an LCS 2.0. That could be a joint program with the USCG OPC.

        The timing is perfect.

    • Tim, Title 14 of US Code also comes into play in this situation:
      “and shall maintain a state of readiness to function as a specialized service in the Navy in time of war, including the fulfillment of Maritime Defense Zone command responsibilities..”

      There is plenty more within the Code that dictates the US Coast Guard as a National Defense force and if people disagree with the USCG as a full military force, they should petition to have Congress re-write the Code, until that point we need National Defense Capacities. And yes, I liked ADM Yost, haha

  4. “WMSL (6 mounts) requires 19 people – 3 per gun plus control officer.”

    Only if you are fighting all the gun mounts a the same time and not even then. The 82s in Vietnam had five mounted .50 caliber machine guns with a crew of eleven or twelve. In reality, the single gun requires only 1.5 people. During one fire mission, I was my own loader and gunner for about 800 rounds which was only eight boxes and all the ammunition available forward. It isn’t that hard.

    The after four mounts had one passer/loader. That made 1.25 people per gun mount.

    • 19 wasn’t a guess, it was what ATG required. We got them down to 13 by splitting the loader and mount captain between the mounts.

      Why would you crew a ship from the beginning to not be able to properly man all of the mounts?

      An OPC isn’t a vietnam-era patrol boat and a standard naval gun crew is 3 people. The most realistic threat an OPC will ever face is a small fast moving attack craft and the emerging tactic is to swarm. Small caliber is important, proper gun crews are important, and the ROSAM is a much lighter/easier to maintain/cheaper option. Its also can accept a large variety of mounts other than the M-2.

      Bill, you were all made of tougher stuff back then

      • “Why would you crew a ship from the beginning to not be able to properly man all of the mounts?”

        The Coast Guard has always under crewed its gun mounts. The 5″/38 consumed about fifteen people in the mount and the upper handling room and not to include weapons control. There was no one assigned to the magazines to send up more if it were needed.

        “An OPC isn’t a vietnam-era patrol boat and a standard naval gun crew is 3 people.”

        Yep, fully aware of this. Just because the navy does something, does not necessarily make it right. I’ve seen these mount at GQ aboard navy vessels. They are so crowded in some stations they are tripping over each other. Why is a “mount captain” needed for a machine gun? Why all the loaders when the real solution would be to expand the size of the ammunition box, as the navy did in Vietnam and much later.

        Not tougher, just fewer people to pick up the load.

      • I would challenge the assertion that “The most realistic threat an OPC will ever face is a small fast moving attack craft and the emerging tactic is to swarm,” that .50 cal and similar light weapons are critical to its survival, and the implied assertion that the ship would be better off with ROSAM than Mk38 mod 2. (Not to say ROSAM could not be a useful replacement for crew served .50 cal. machine guns on the NSCs–I think we agree on that. I also believe they are planning to mount ROSAM on the OPC in addition to the Mk38 mod 2 and crew served .50 cal., but apparently they are referring to them as SSAM now.)

        A note to those unfamiliar with these mounts: Both the ROSAM (new name SSAM?) and the Mk38 mod2 are stabilized mounts for weapons. Both originated in Israel where the Mk38 mod2 is called the Typhoon and the smaller ROSAM is called the mini-Typhoon. http://en.wikipedia.org/wiki/Typhoon_Weapon_Station

        In normal peacetime environment the ship is unlikely to be challenged, particularly by a small boats with weapons of comparable effective range, like small arms, machine guns to 14.5 mm, and rocket propelled grenades.

        In law enforcement cases, the adversary is very unlikely to put up a fight, knowing he has a much better chance in court.

        In the case of a suicidal terrorist attack, using a vessel, if a ROSAM would work, heavier weapons would work better. If the terrorist vessel is of any size, then the cutter would need heavier weapons than can be mounted on the ROSAM.

        The only case where we would be likely to encounter a swarm is vs. Iran in the Persian Gulf. (1) The OPCs are unlikely to go there, but if they do, hopefully their crew and their armament would be augment. And (2) the swarm of small boats with their short ranged machine guns and 107mm rockets are really just screen and distraction for the more formidable threats that include torpedoes and cruise missiles that out-range the ROSAM’s weapons. Even in dealing with the small boats the Mk38 mod2 would be superior. Being capable of using an explosive round, each hit is much more destructive.

      • Chuck, its weight, space, and cost. The SSAM will do the job and can be operated in a port environment with less collateral damage. These shouldn’t be the main mount MK48 or higher is needed for stopping power. The SSAM/ROSAM is suppressing fire and knocking out personnel.

        I saw the deck space compromises made on the WMSL and I’m not a big fan of dropping MK38’s all over the place in a peace time role. They just get in the way. The SSAM is relatively small. Lets account for the space, weight, and power of the MK38 but install SSAM’s and leave the space clear so the OPC can do its 99% mission. It accomplishes the ATFP needs for port transits.

        Bill, in a war time environment where the gunner can shoot at will, you could likely reduce the persons per mount.

  5. For a reality check on my proposed design armament. I looked for vessels of approximately the expected size of the OPC that were similarly equipped and had found a couple:

    a Thai frigate: http://en.wikipedia.org/wiki/HTMS_Naresuan
    and the Meko 200 series (25 ships in five navies) best exemplified by the modernized ANZAC frigate HMAS Perth:
    http://en.wikipedia.org/wiki/Anzac_class_frigate#Royal_Australian_Navy

    but another, a new Korean frigate, has just come to my attention that is probably even closer:
    http://www.defenseindustrydaily.com/FFX-Koreas-New-Frigates-05239/
    and here: http://en.wikipedia.org/wiki/Incheon_class_frigate

    All of these do have combined diesel or gas turbine power plants and are faster than required for the OPC.

  6. I think the Navy should be talking to Korea about a real LCS…as opposed to the water ski platforms they currently are touting.

  7. I think in this situation, DHS has to deal with the fact that these cutters are going to cost them money, and there is no way they can be as mission effective as needed if they start gutting them of capabilities. There is nothing in these designs that is extravagant, they are simply requesting for a solidly capable cutter, one that will be as effective on its first day in the fleet to its last day 40 to 50 years after commissioning.

    I know I am sounding like broken record with the SIGMA Class Corvettes, but they meet so much of the USCG’s OPC needs. They are currently in operation with the Indonesian and Moroccan Navies, with future use with the navies of Oman and Vietnam. I know I am just a humble enlistedman, but I think the smartest decision the USCG made in Deepwater purchasing of surface asset was the FRCs. We looked at was currently being used effectively, purchased the hull design and built it for our missions.

    • Those with stars and eagles would do well to heed the advice of those with pewter pins, chevrons and anchors. You are taught as a JO to humble yourself and look to you enlisted for guidance, knowledge, and experience. At some point, some officers just start thinking they are the only person with a valid perspective. I think you are spot on.

      I like the Holland class from DAMEN but it doesn’t currently meet the 7.5k range (next size down from the SIGMA). The SIGMA is pretty slick, I went on the Indonesian version in San Diego a few years ago and was really impressed. What troubles me is that the range listed in the draft requirements is going to be difficult to meet without kicking the hull size up (both classes are listing ~5K). I’m worried about the cost required to meet the range, that is while still meeting the speed as well.

  8. I think this is a very interesting topic and am glad that you’re exploring it. There seems to be a reflexive instinct throughout government that new equipment (e.g. cutters, aircraft) should be an upgrade (in all respects) over their predecessors, irrespective of the changes in threat environment. This is in part why nearly every new ship/aircraft is physically larger than the craft it replaces, and why construction and operating costs go up so much greater than inflation. I think CG started doing the right thing in viewing at the fleet as a system and working through what a next generation “clean sheet” fleet would look like. Unfortunately, I think their contractor failed rather miserably at this task, and CG’s left with a mess of a shipbuilding program. (Navy didn’t appear to do much better with the LCS — I applaud their willingness to not just build FFG replacement/upgrades, though I think that they fouled up the execution pretty badly.) Here’s hoping that CG will think through the issues that you’re raising.

    LCS 2.0 is unlikely to be effective for CG. Navy doesn’t need (or want to pay for) the range/endurance that makes for an effective CG major cutter. Advances in propulsion technology aren’t going to change this tradeoff appreciably in the coming decade.

    I like the weight/buoyancy analysis, but it’s somewhat more complex than weight alone. Adding large weapons systems to the deck/superstructure will have a sizable impact on stability, and stability is probably the limiting factor for a conventional hull design.

    I don’t think that converting an OPC to an ASW platform is feasible. The most likely ASW threats (modern, quiet diesels) are almost undetectable to surface towed array systems if they are operating at normal cruise speed/depth, and the OPC’s detection ranges are inside of the sub’s weapons envelope. In other words, the likely first indication that the OPC will have of the sub’s presence in wartime is an incoming torpedo. On the extraordinarily unlikely chance that an OPC encounters a nuclear sub traveling at cruise speed and detects it first, the surface-launched lightweight torpedoes are very ineffective due to their limited speed and range. There’s also a personnel problem — maintaining a watch on a sonar system is personnel intensive. Where do the extra bodies go, how long will it take for them to become proficient with the newly installed system, etc.? (I’ll note that the exception to the above generalization is the LFA SURTASS system, but I don’t think an OPC is well-suited to be a platform for this system.)

    • I agree that adding a towed array sonar to the OPC is not a cost effective move. The better move is to make sure the flight deck can accommodate a helicopter that is ASW-equipped.

    • I’d like to address Ahab’s comments:
      “LCS 2.0 is unlikely to be effective for CG. Navy doesn’t need (or want to pay for) the range/endurance that makes for an effective CG major cutter. Advances in propulsion technology aren’t going to change this tradeoff appreciably in the coming decade.”

      The thinking was that if the cutter were a viable warship, when the Navy recognizes the mistakes they have made and start looking for a follow-on, the cutter, already in production would be an attractive alternative, complete with lobbyist and a Congressional delegation in support. And yes they would probably trade-off some range for other capabilities just as we might in the full up warship version.

      “I like the weight/buoyancy analysis, but it’s somewhat more complex than weight alone. Adding large weapons systems to the deck/superstructure will have a sizable impact on stability, and stability is probably the limiting factor for a conventional hull design.”

      True it will have an effect, but the same could be said for the changes to the smaller 255s where virtually all the weight I sited was above the main deck. The variations have to be considered, but I believe they are all feasible. If the ship is stable with the weapons on board, it will be even more stable with fewer mounted. The concern would be that the ship would become too stable, but that can be addressed by loading less segregated ballast water as the fuel is burned off.

      “I don’t think that converting an OPC to an ASW platform is feasible. The most likely ASW threats (modern, quiet diesels) are almost undetectable to surface towed array systems if they are operating at normal cruise speed/depth, and the OPC’s detection ranges are inside of the sub’s weapons envelope. In other words, the likely first indication that the OPC will have of the sub’s presence in wartime is an incoming torpedo.”

      I would expect the ships to operate in teams, three or four ships plus helicopters. The towed arrays are needed as cuing sensors. The AN/SQR-20 Multi-Function Towed Array (MFTA)(Thales CAPTAS 4) has been selected for the LCS and new construction DDGs. It has both active and passive modes, so it is effective against even the quietest submarines. It is also the longest ranged tactical sensor available for US surface ships, well outside normal torpedo range. I have not heard that they have made any special effort to make the LCSs quiet. The Coast Guard wants to make the OPC quiet for there own reasons. If the CG chooses a hybrid or integrated electric propulsion system there is a good chance it will be naturally quiet, but if the ships are going active against quiet diesel electric subs that is not the issue any more anyway.

      Going active probably does mean that the sub can counter-detect the escort at even greater range and may provide enough information for a missile launch. But against a team of ships and helicopters, a missile launch may be suicidal and the sub typically has other targets in mind. This has pretty much always been the case. In WWII torpedo ranges were well beyond sonar ranges, but shots from that distance were generally not effective. We still have counters to long range torpedo attacks.

      “On the extraordinarily unlikely chance that an OPC encounters a nuclear sub traveling at cruise speed and detects it first, the surface-launched lightweight torpedoes are very ineffective due to their limited speed and range.”

      Over the side light weight torpedoes are only a last ditch urgent attack weapon. Helicopter launched torpedoes are the primary weapon. On the full up warship, vertical launch ASROC could provide an intermediate range weapon.

      “There’s also a personnel problem — maintaining a watch on a sonar system is personnel intensive. Where do the extra bodies go, how long will it take for them to become proficient with the newly installed system, etc.?”

      Presumably you are talking hear about upon mobilization. True, but this is only a small part of the total mobilization problem. Fortunately we can fall back on the Navy training system for sonar expertise. A huge increase in CG sonar techs is a much smaller increase in total Navy/CG sonar tech training requirements. If some of the ships were already equipped with the system, the transition would be easier.

      • Chuck, as much as I think the 255s were an ideal size for a WMEC/WMSM/OPC, they had HUGE stability problems: “Memorandum about 255′ Cutters Excessive rolling; recommendation for installation gyro stabilizers – ‘The undersigned officer agrees with practically all remarks, believing that these ships are the most inhuman ever utilized by the Coast Guard.’ – E. A. Coffin, Jr. Commanding Officer USCGC Sebago (WPG-42)”. Note that this dates back to when they were still designated WPGs, and later, when their designation changed to WHEC, they had most of the ordinance you are advocating removed. (Most likely to reduce top-weight to address the rolling issue??) I do not know for certain that the rolling issue was ONLY due to top-weight, as it is noted that for ice-capability they were designed with flair at the waterline and my suspicion is that the combination of flair with all the top weight from the weapons was the culprit.

        Even if they rode poorly, they were some awesome-looking ships, and really heavily armed for their size!

      • Actually it might have been because they did not add back in top weight after removing the ordnance and that made the ship “too stable.”

        When was the report? The weapons were reduced right after WWII, but the WPG designation persisted until the mid 60s. The change to WHEC did not reflect any change to equipment. All the large cutters, 327s, 311s (when we got them), and 255s, reduced their weapons fit after WWII presumably to minimize maintenance and manning requirements. The 255s were known to ride badly even when I was commissioned in 1969, long after the weapons had been reduced.

        It may seem counter intuitive, but if the ships were too stable, because they had been designed to have a lot of weight topside and it was removed, the ship would have excessive metacentric height, and would right itself so fiercely that it would be very uncomfortable.
        http://en.wikipedia.org/wiki/Metacentric_height

        On a modern ship, stabilizers could mitigate this.

  9. The July 2012 US Naval Institute Proceedings has an excellent article by the CNO that can be accessed here: http://www.usni.org/magazines/proceedings/2012-07/payloads-over-platforms-charting-new-course

    He is advocating decoupling development of platforms (ships and aircraft) from payloads (weapon systems and sensors), by providing standard interfaces and investing in reserves of space, electrical power, and cooling capacity.

    Looks like a lot of it is applicable to the OPC.

    • Interesting article, all of the sacrifices for stealth may no longer be worth it. Great points made, thanks for passing it along.

  10. Chuck after reading CNO’s lates comments of Payloads vs.Platforms, I would suggest that the OPC design needs to be modifiid in order to accept Modules. Can that be done within the existing design parameters? Or does one need to go up to an NCS to gain adaptibilty? It is kind of the essence of your argument.

  11. I have been hoping the specs would a requirement that the ships be ccapable of using the OPC modules, but so far that has not been included. Going to an NSC would not help. It is not designed to accept modules either, but at least the Commandant is talking about specifying extra weight moment for the OPC.

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  13. Our current DHS Secretary doesn’t seem to view us as a military service with a national defense role. Cutting our legs out from under us on NSC’s 7 and 8 proves to me that even within DHS we are the “red headed step child”. It doesn’t even seem to me like our Commandant sees us as a true military service with a national defense role. We are a sea going armed “naval type” service, but it seems like his vision is of our service as a strictly law enforcement agency. The Commandant seems to be purging all the “naval traditions” from the Coast Guard. The newest uniform changes seem to prove that point. I hate to say it, but until this administration leaves office and we get a new DHS secretary that advocates for us rather than push the POTUS’s agenda, I don’t see the OPC having any wartime role or capabilities. I’m still skeptical that they’ll ever be built. I didn’t like the “Guardian” title, but I miss Admiral Thad Allen. It seemed like he was trying to re-enforce our military identity and partnership with the Navy, while our current Commandant seems to be doing the opposite. JMO

  14. From my point of view, the CG has a national defense role which it is executing right now – Homeland Defense. In the modern era (electronics revolution and age of terrorism/assymetric warfare), a portion of the nation’s defense must be spent on guarding the sea frontiers. Think of it as the nautical version of the Army’s “defense-in-depth.” The CG can NOT send its assets gallavanting off to a foreign theater of operations and leave the sea frontiers un- or under-defended. This does NOT mean the CG is less important than the Navy either, and it does NOT mean the cutters should be under-equipped nor poorly armed.

    So, from a national-defense-mission perspective, what threats should the CG equip its cutters to handle? Well, assuming the main theater of operations is overseas and the Navy’s assets are utilized in that high-threat environment and the CG provides the defense-in-depth around CONUS (& AK / HI), I envisage a few means of attacking the homeland by an enemy:
    1) Nuclear Submarines positioned off our major ports to conduct Anti-Shipping-Missile and torpedo attacks against our shipping. They could also mine entrances to ports.
    2) Merchant ship attack via: WMD (to include LNG tankers), “kamikaze” (purposely colliding a high-value asset dockside or doing so in a constricted harbor entrance), mining, or possibly even a modern-day version of the Q-ship equipped with missiles and guns which are used once they’ve been admitted into a port.
    3) Long-range aerial attack from the enemies homeland (bombers), which could have a maritime component in that they could attempt to mine CONUS ports.

    Dealing with these one-by-one:
    The OPC’s operational area would put it as the #1 sea-based ASW asset to protect the homeland. This should be defense mission priority ONE, in my opinion. The Sectors should have the communications and electronics in place, as well as a contingency plan to stand-up an “ASW Ops Center” to interface the OPC’s ASW capability (weapons, sensors, and embarked USN MH-60s) with USN P-8 aircraft. This would provide powerful protection of SLOCs within the MDZs. I completely agree with and support Chuck’s arguments that the OPCs should have the next-generation TAS, H-60 capability to utilize Navy Reserve SH-60s and MH-60s, and ship-based A-S weapons (probably ASROC, although there has been “discussion” in the Navy for years about equipping surface vessels with 21″ TTs for the Mk.48 ADCAPs since the lightweight torpedoes are marginal against modern submarines). I would add that to make this capability robust with shared sensor data and cooperative engagement with the Navy, a SCIF would be beneficial, if not out-right mandatory.

    To counter the merchant shipping threat, the OPCs (as well as FRCs & WPBCs) are going to need robust communications, data, and on-shore information clearing house. (See what I mean about the CG already DOING a defense mission right now?) Assuming full-blown shooting war with a major foe, AIS will probably be discontinued, at least by the combatants and possibly by everyone. This means cutters again become the primary sensors detecting and interrogating shipping along and approaching the US. Therefore a robust capability with radars, ESM, sonar, UAVs, and manned aircraft is essential. Of course to provide this info to (and receive a complete tactical picture from other sensors from the coordination center), a SCIF becomes mandatory. Additionally, to properly execute this mission cutter boats will be needed for VBSS, and a boarding team which can fast-rope (DOG) from the helo for more distant boardings would require more berthing space as well.

    As far as aerial targets, in my opinion, it would be far outside the scope of CG missions and capabilities to install a useful capability in a cutter, especially one as small as the OPC. This is a mission the USAF (probably via the ANG or AFRes) and USN (probably via an aegis-equipped, counter-TBMD Burke located to block missile threats but still retaining an anti-air capability). I still agree with Chuck that the OPC should have some sophistication to its air search and track radars for counter-smuggling, UAV-support, and SAR. This level of capability still provides defense-related capability, since it provides a network of at-sea sensors, which can provide redundancy for identifying aircraft approaching the US.

    As opposed to the anti-air mission, the other two mission areas’ equipment and capabilities greatly overlap with peace-time mission areas, such as migrant-interdiction, counter-smuggling, and SAR.

    In my above assessment of the threat, you may have noticed mining the US ports is a major threat and all three types of anticipated attacks have a mining capability. The US Navy has been running away from the mine countermeasures mission area with wreckless abandon, considering the US Navy has had two major casualties due to mines in the Persian Gulf… In my opinion it would behoove Congress to appropriate money to develop a mine countermeasures module which can be placed on the WLMs and WLBs to ensure the US domestic ports have a robust counter-mine capability at minimal cost.

    I am pleasantly surprised they are intending to make the OPCs have some ice-capability. Might negate the need for a seperate class of Arctic Patrol Cutter, although, it would depend on how “capable” they are…

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