Canadian Icebreaker/Offshore Patrol Vessel Procurement

The Canadians are currently contemplating new ship procurements that include icebreakers and off shore patrol vessels (OPVs) not unlike the choices facing the USCG. Here is one unofficial view.

Related posts:

Arctic Patrol Vessel

WMEC 270 to OPC

Guns for the Offshore Patrol Cutters

“Design” and Offshore Patrol Cutter Today

25 thoughts on “Canadian Icebreaker/Offshore Patrol Vessel Procurement

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  2. Shades of FDR,
    “AOPS Project Management Office looks to spend $3.1B for 6-to-8 6000+ ton, limited-duty, military icebreakers. As class 5 icebreakers, the AOPS’ Arctic duties will be limited to summer and to the beginning and the end of ice season in the Northwest Passage. ”

    In April 1941, Treasury Secretary Morgenthau held a meeting with his staffers about the Navy’s take over of the Coast Guard when war was declared. The matter was not in question and they waited for it to begin. Admiral Waesche had been a previous meetings. One of the topics was ice-breaking.

    Morgenthau reported his conversation with FDR on ice-breaking. FDR said, “Well, Coast Guard knows more about ice breaking than any other organization,” continuing, “we ought to have at least one or maybe two of these very big ones like the Russians have got.” FDR then authorized Morgenthau to begin designing them.

    At the meeting of his staff, Morgenthau noted, “he [FDR] would like two of those [ice-breakers] and five of the other kind, the two hundred fifty footers.” There was some misunderstanding of just what the latter would involve. One member, asked if the 250-footers were to have ice-breaking bows and Morgenthau answered in the affirmative. However, rather than build ice-breakers on the order of the Russians, Morgenthau asked if a shoe could be fitted but his staffer reminded him that this was not very efficient for the work because of the the ride up and crack down on ice procedure. Plus, the vessel pushing the shoe would not have an ice skeg to keep it from “docking itself” on the ice.

    The same staffer suggested building ten 250-footers but Morgenthau kept the number at five because the larger ice breakers would cost about five million dollars or more. Besides Morgenthau said, “Waesche has one [large ice-breaker] designed and he has the designs of the one the Russians used.” It would seem that there had been some intensive pre-war planning with design work. Waesche, like Morgenthau, knew a war would free up funding. Besides, Morgenthau relayed FDR’s attitude. “Well, this is something that [the] Coast Guard is going to do when the war is over anyway.”

    And so the Wind Class were begun, however, it would be a couple decades got the ice-breakers designed by Waesche and his staff. See the Wikipedia

    You have to hand it to Morgenthau and Waesche. They knew their stuff.

  3. I just edited the post to add links to previous posts on the topic of arctic patrol vessels and offshore patrol cutters.

    For arctic patrol we could do worse than build some Wind Class updated with new technology and lessons learned since the 40s.

    Actually the CG got to use several of the Wind Class during WWII. Eastwind and Southwind were both Coast Guard when they captured the German trawler Externsteine. Apparently two, the second Northwind, WAGB 282, and the Eastwind, WAGB 279, stayed with the CG from commissioning, while some of the others were first assigned to the CG, then lend leased to the Soviets, operated by the Navy after being returned in the 50s and finally handed backed to the CG in the 60s. I had not been aware of the Canadian Wind Class Breaker, Labrador.

    As to the OPC, I’m hoping for something more than the PV85, (279 ft, 1900 tons, 22 knots, hanger for a single helo, and a 25 mm autocannon).
    I’m hoping for something around 300ft, 2500 tons full load, 25 knots, and a hanger for two H65s or one H-60 and UAVs, as well as a medium caliber gun and space and weight-moment margins to add systems in the future.

  4. As for the Royal New Zealand Navy’s The Protector class offshore patrol vessel, wouldn’t you want to have the ice capabilities and lengthen the hull so you can accommodate the same gun that is being used on the National security cutter.

  5. As the article noted. There is a penalty for ice strengthening in terms of fuel economy and speed, if you have it when you don’t need it, so I doubt we want to ice strengthen all the OPCs, but we do need some ice capable ships. 225s could probably do some of what we want, but they don’t have any helicopter facilities. We will probably have a small sub-class of OPCs that are ice strengthened. In addition we going to need true icebreakers both to replace the Polar Class and for expanded missions. At least a couple should be as capable as the Polar Class but others might be smaller. We are going to need to keep at least one breaker in the Arctic during the summer months to extract ships that get in trouble in the ice (including our own).

    If we are going to be building big ships, and icebreakers generally are big ships, at least by Coast Guard standards, I would like to see them have aviation facilities that go beyond simply ice recon. The ability to embark up to three Navy MH-60R/S and magazine space for their weapons and sonobuoys would be a good investment. We should also anticipate that they will embark significant numbers of people over and above the crew and aviation detachment.

    As for the OPCs, I’m hoping for something better than the Protector Class. Realistically I don’t think we will build anything like the 357 ft ships that were at one time described in some detail on the Acquisition Directorate website, That description has been deleted, but I am hoping for something around 300ft and 2,500 tons, with a speed of at least 25 knots, at least two boats including at least one long range interceptor, a flight deck and hanger for two HH=65s or one H-60 and UAVs, magazine space for arming the helos, and a medium caliber gun, CIWS, and two of the 25 mms as used on the Webber class.

  6. I smell a joint program. Decreased costs (for each country by sharing development costs as well as a larger class-size allowing economies of scale by the builder), very similar needs, inter-operability/support with our northern neighbors — all looks like a win-win to me. Build them at Marienette Marine with modules/components from Canadian sourcing and all the politicians should be happy while maintaining price efficiency.

    We don’t need and shouldn’t want more 240′ WLBBs. The Arctic Patrol Cutter mission is neither an icebreaker mission, nor an ATON mission, and this is what the new Mackinaw was built for (and it’s ideal for the Great Lakes, but not the Bering Sea). The Acushnet, Alex Haley, Storis, & WHECs are for heavy seas and did not have the design compromises the WLBB does. (Granted the Storis was based on a WLB design enlarged and with ice strengthening, but it was built as a supply vessel, not a patrol ship.)

    Built like I describe in the Arctic Patrol Vessel thread, and it would do all these different jobs very well.

  7. There are several countries that are allies that are interested in arctic patrol vessels. Probably worth exploring. I think US law prevents us having ships built outside the US, but since its now common to have major assemblies built in one country and final assembly in another, is it a US built ship if the “content” is 51% made in the USA. Damen would probably be happy to have hull sections built for us in Eastern Europe and barged to the Great Lakes.

    Bill, I would have thought that one of the types of SAR cases we would see is that of vessels trapped in shifting ice. Since the vessels themselves are likely to be ice strengthened, I would have thought the vessel going to their aid would need to be a bit more capable–designed for first year ice perhaps.

    Do you really think the X-Bow is appropriate for a ship that expects to encounter ice?

  8. Hi Chuck. I agree completely with you. Without getting into why, it’s clear the polar ice is shrinking, and that means increased traffic farther North, which exposes the possibility for just the scenario you are describing, so yes, I agree with your thoughts completely.

    First off, I was originally thinking about a double-ended ship, with the icebreaking capability being via a stern-first passage. It’s been shown Z-drives (or any kind of azimoth thruster) improve icebreaking action when the ship is driven stern-first through the ice, and quite frankly, I thought as you did that the X-Bow would be quite inappropriate as an icebreaker. (I mainly feel the X-Bow is such an asset because of the rough seas so prevalent in the Bering Sea, which improves ride which helps operations and reduces transit times.) For information about double-acting ships check these links:

    Click to access MombXDat.pdf

    Then, while I was perusing the Ulstein website, I ran across a press release about some X-bow ships that have been built to break ice. They are seismic exploration ships built for Polarcus and they have DNV’s Ice 1A classification, which means it can press on through first-year 1.2m-thick ice. Links:

    Click to access ULSTEIN%20SX134%20product%20sheet.pdf

    So now I’m second-guessing my own design… 🙂 May not need a double-acting ship hull with X-Bow ahead and an icebreaking transom. That means I could include a transom boat ramp after all. I guess it would really come down to what saves the most weight – a dual-acting hull with ice strengthening all-around and breaking stern and X-bow, or an X-bow reinforced for icebreaking ahead with a standard transom with boat-ramp…

    I originally liked an amidships, large bridge, because the double-acting hull requires equal affinity of control operating ahead or astern, but it’s also great for helo ops, rescue ops — heck, just about every kind of op I can think of… Imagine the Icelandic CG vessel Por with an Ulstein X-Bow, and that’s REALLY close to what I had in mind:

  9. You realize the Mackinaw has trainable electric propulsion pods they call Azipods, and that it can break 32″ of ice continuously either ahead or astern?

    The things I don’t like about the Mackinaw are the speed (only 15 knots), the low freeboard at the buoy deck (although I think it is at least as high as the Storis), and the lack of either a flight deck or hanger (Looks like at least a flight deck could be fitted, with more changes maybe a hanger. Looks like the boat handling facilities could be better too.

    Still I think they could be useful ships. They might replace buoy tenders that are already there, while providing seasonal icebreaking and they would also be useful for logistics. They are a good size; have the range; and sea keeping has to be pretty good. The lakes can also get nasty (worst roll I ever experienced was on the old Mackinaw during the summer).

    At least at one point the announced intention was to base the Canadian Arctic patrol ship on the Norwegian Svalbard:

  10. Yeah, the new Mackinaw has very good icebreaking, but it is a compromise vessel, and in my opinion, Dist. 17 MECs have been compromises for far too long. The only vessel ever made for the job was the Storis (kind-of – Greenland Support was close enough to make it darn good in the Bering Sea). All the rest were conversions of something elses. (For that matter, so was the Storis, but it was the most idealized Arctic cutter so far.) The new Mackinaw is great for what it is. It does ATON in the Summer and Icebreaking in the Winter, but it is not a patrol vessel. It has no real flight deck, and (unqualified opinion – I’ll have to look closer at some pictures / diagrams) I can’t imagine there being one without redesigning the whole superstructure. I think the Mackinaw’s low speed has to do with adding a lot of hull plating (not to mention the weight of the longer hull anyway), which necessarily slows down a ship unless the horsepower is significantly increased.

    In my opinion the most important aspect of an arctic patrol cutter is the flight deck and having an H-60-size (or greater) capability. Having such a platform in the Bering Sea would extend the range of H-60s flying out of Kodiak far and wide, which means faster rescues and/or the ability to do repeat flights to the same rescue allowing greater numbers of people to be recovered.

    I don’t think the low freeboard is necessarily a bad thing. It can make direct-rescue ops from sea to deck easier.

    I hadn’t seen many pics of the Svalbard before. She’s a very ideal ship for this type of mission, although I think she’s a bit big for what the CG needs for the Bering Sea.

    What did you think of the Por? (It’s based on the Norwegian Tromso, so it’s also similar to the Svalbard, again, being larger than I think is necessary/prudent.

  11. Just compared the Juniper to the Mackinaw, and yes, the speed problem does have to do with the power-to-weight ratio (mainly). Juniper is 2000 tons with 6200 hp, and the new Mackinaw is 3500 tons with 9100 hp. By my calculations thats approximately a 40% increase in weight with only a 30% increase in power. Of course, there’s effects of length-to-width ratio and differences with the azipod propulsion on Mackinaw vs. traditional shafts and props on the Juniper-class.

    After re-reading my above post, I wanted to interject one correction to my generalized statement that the H-60 capable flight deck is most important. As far as the lay-out of the ship itself, if we’re making a purpose-designed Arctic cutter, it’s hullform and superstructure should be idealized for that mission, and the flight deck is one of two or three factors of primary importance (the others being ice-stengthening and high-performance operation in the heaviest seas). It’s not the only possibility, but clearly, the X-bow has some really attractive qualities that (in my opinion) make it the world leader in rough seas transit and ops capability, so that’s why I picked it. Another design which could perform better would supplant that design, if such were available.

  12. Since Juniper and Mackinaw are nearly the same length and nearly the same speed, it would make sense that horse power requirements (hp/ton) would be closely related to displacement, but as you start going faster, for conventional displacement hulls, speed to length ratio becomes dominant with horsepower requirements rising geometrically as speed approaches two times the square root of the water line length in feet.

    Some examples; fl=”full load”; wl=”water line length”; oa=”over all length”:
    Iowa Class Battleship, 57,540 tons (fl), 860 ft (wl), 212,000 HP, 32.5 knots—3.6 HP/ton
    Essex Class Carrier, 34881 tons (fl), 820 ft (wl), 150,000 HP, 32.5 knots——4.8 HP/ton
    Cleveland Class Cruiser, 14,131 tons (fl), 600 ft (wl), 100,000 HP, 32.7 knots–7.1 HP/ton
    Gearing Class Destroyer, 3460 tons (fl), 383 ft (wl), 60,000 HP, 36.8 knots–17.3 HP/ton
    National Security Cutter, 4,500 tons (fl), 418 ft (oa), 49,875 HP, 28 knots–11.1 HP/ton
    Fast Response Cutter, 353 tons (fl), 154 ft (oa), 11,600 HP, 28 knots———–32.9HP/ton

    To drive the NSC, with its relatively broad beam at 33 knots, we would probably have to at least match the Gearing’s HP/ton.
    To drive the FRC at 33 knots, we would probably have to double the horsepower, about 66 HP/ton, and it is probably a semi-planing rather than a true displacement hull.

    Since the X-bow would not lift nearly as much as a conventionally flared bow-reduced pitching, looks like the foc’sle would need to be a deck higher, to keep green water from coming over the bow, but that would be compensated by the fact that the foc’sle is shorter for a ship with the same waterline length. I’m still unconvinced that it is a good choice for an Icebreaker. If the most forward point were a few feet underwater, instead of at the water line, I might say it makes as much sense to push the ice up and to the sides, as to push it down and to the side, but the bow form for the Polar Class or the Mackinaw just seems to make a lot more sense than ramming directly into the ice with a broad round bow. For ice free areas it has always been a mystery to me why submarine and torpedo hydrodynamics are better with a round bulbous bow, while ships have gone with narrow knife blade type bows, exception being the bulbous forefoot under some designs, but they are optimized for a particular speed.

    In the Norwegian Coast Guard the Tromso has been replaced by the Barentshav, which has a very unique propulsion setup,

    Bill, I don’t understand your affection for the Islandic “Por” class design since I see no indication that it is even ice strengthened, much less an icebreaker, it has no flight deck, and its speed is less than 20 knots. The “Harstad” which it was based on was “…optimised for emergency towing of large oil tankers (up to 200,000 metric tons deadweight (DWT)), oil spill clean-up and fire fighting.”( Towing large tankers and firefighting have not been high priorities for the Coast Guard; do you think they should be?

    If we wanted to design a ship from scratch, we could probably create a light icebreaker with a speed over 20 knots, a helo deck and hanger, good boat handling facilities, weapons fit similar to the NSC, and still keep it under 4,000 tons.

    • Thinking about my question of why sub/torpedo choice of bow is different from surface vessel choices, I now recall, subs and torpedoes are hydro-dynamically deep, meaning they don’t make waves. You would get the same kind of solutions if the ship is not going fast enough that wave making is a significant consideration. Suspect the X-bow may be a good solution primarily where sea keeping is a primary concern and speed/length ratio is relatively low.

      So, Bill, are you proposing a double acting arctic patrol vessel with axipod propulsion (breaking ice by going astern)? In that case I can understand why you would not need an icebreaker bow on the ship.

  13. “[i]So, Bill, are you proposing a double acting arctic patrol vessel with axipod propulsion (breaking ice by going astern)? In that case I can understand why you would not need an icebreaker bow on the ship.[/i]”

    That is exactly what I was thinking. However, as I noted above, there has been successful light icebreaking designs with the X-bow in typical forward propulsion (with the limitation of first-year ice less than 1.4m thick), therefore, I’m back to wondering if the double-acting design with majority ice reinforcement at the stern is more effecient, or if the reinforced X-bow for ahead-icebreaking is better…

    You brought up some doubts about x-bow’s icebreaking, and I agree with them in premise; however, you and I agreed earlier that the ice operations would be limited to first-year ice of about 1m or so at most, and the X-bow using the pushing and displacing underneath and to the sides is apparently fully capable of that.

    The lack of a spoon-bow to ride up and over and crush down on heavier ice is probably why we will never see any heavier ice-breaking capability out of an X-bow design. If that level of icebreaking is desired, I’d stick with the double-acting hull and use the spoon-shaped stern to do the heavy breaking.

    My affection for the X-bow is that the Bering Sea has some of the nastiest sea states on a regular basis. Combine that with the fact that ice operations would be limited pretty much to Winter, and the compromise design of putting an ice-breaking spoon-bow on the Arctic Patrol Cutter really hampers it for 70% of the year. And, I bet of the remaining 30% of the year, actual ice-breaking would occur 5% or less of that time. I still agree that it’s a critically important capability, but not enough so to compromise the design for the rest of it’s operations. Also, one must worry that if the APC is made too good of an ice-breaker, it might hurt funding for replacement of real icebreaker platforms.

    “[i]Bill, I don’t understand your affection for the Islandic “Por” class design since I see no indication that it is even ice strengthened, much less an icebreaker, it has no flight deck, and its speed is less than 20 knots.[/i]”

    My affection for it is simply in it’s general lay-out. I’d change the bow to an X-Bow, and I’d completely change all the superstructure aft of the bridge. It’s general size is slightly larger than what I have in mind, but it’s bridge forecastle (aft of the breakwater) are just what I had in mind. The foc’sle ahead of the breakwater would not exist (or would be vastly changed in size and shape) by switching to an X-bow. Looking at the picture in the link I posted, everything from the crane aft would be changed. About where the crane is would be the hanger, and a flight deck would extend aft from there to almost the transom at what I would estimate to be 1-1/2 decks higher than the quarterdeck show in the photo (which does look like it’s a work-deck designed for towing, as you note). So, it’s really a starting point. So far I haven’t seen any OTS design that could be bought or slightly modified which would do everything well.

    “[i]If we wanted to design a ship from scratch, we could probably create a light icebreaker with a speed over 20 knots, a helo deck and hanger, good boat handling facilities, weapons fit similar to the NSC, and still keep it under 4,000 tons.[/i]”

    That is exactly what my design is. Length: 278′, Beam: 47.5′, Draught: 19.5′, Weight: 3750 tons; H-60 size flight deck & compact hanger; Mk.110 on forecastle, Mk 38 atop hanger, M-2HB on each side at rear of bridge; electronics identical to NSC; extensive medical suite; & flexible/expansion area for palletized cargo, emergency housing of survivors, etc.; a new arctic cutter boat (which is a cross between the LRI & ASB); X-bow for high seakeeping ability and speed in weather; Double-acting hull with reinforced stern for light icebreaking while running astern; Bridge with 360-degree visability (due to ice-breaking astern as well as improved all-around capability).

    You got me thinking about the CODAD systems in an earlier post (I think on the OPV discussion). With the design I outlined above and azipods (diesel-electric), how much horsepower do you think would be needed for around 25 knots?

    • “how much horsepower do you think would be needed for around 25 knots?”

      Bill, I would suspect 24,000 to 30,000 would be adequate. My rule of thumb is for every additional four knots you need to double the HP.

      Generally, I like where you are going, and tests would confirm or deny the desirability of the X-Bow for this application. I didn’t see any applications of the X-Bow where the length to speed ration was this high.

      The dimensions look a bit too compact for the displacement. Additional length would help the speed. Both the “Por” which is slightly larger (4000 tons) and the “Barentshav” which is smaller (3251 tons) have greater length and beam.

      • “[i]I didn’t see any applications of the X-Bow where the length to speed ration was this high.

        Here is Ulstein’s OTS design for a CG vessel:

        Click to access ULSTEIN%20SX116.pdf

        Note the design is 80m x 16m and has a design speed of 18 knots (length to width ration of 5:1). My design is 85m x 14.5m (length to width ratio of 5.86:1). I figure that difference alone could add a knot to a knot and a half, maybe more. (I still think my design is very “beamy” compared to most of the slender naval vessels – the ratio is beamier than any white-hulled cutter I’m aware of. Only the WAGBs and Buoy tenders are wider. The 210s have a length to beam ratio of 6.17:1.) The Por has an identical length to beam ratio to my design.

        I also found a dandy 290′ Ulstein design that could be modified (by replacing the water canons with .50-cals and installing the Mk 110 on the foc’sle) to an OTS OPV:$file/ULSTEIN_SX119.pdf
        For our discussion about the Arctic Patrol Cutter, it points out that the X-bow can make more than 18 knots (which is what is listed in 99% of Ulstein’s literature), as it makes 21 knots. (It’s length to beam ratio is 5.21:1, and it’s only 3m longer, by the way.)

        For the record, I believe Ulstein lists 18 knots so much because that is probably the max economic speed, and to go higher causes really increased fuel consumption. That would be true with any design though. At the high end of the data charts I could find, the X-bow was still considerably more efficient than a standard bow:$file/ULSTEIN%20X-BOWlr.pdf
        (Go to page three of that document for the data charts.)

        A 327, eh? Wonder where that number came from… For what you were initially advocating, why not go with a new build of the Wind-Class?

        In all seriousness, I think an Arctic Patrol Cutter has to be medium size (250′ – 285′) to operate in the tighter areas/passages such as in the Aleutians, the Inside Passage, and some of the harbors in Alaska; built to operate in (not just survive) any sea state; have light-ice operation capability (at the level you and I agree on); have that H-60-size (or bigger) flight deck and hanger; and have an area with flexibility to do varied missions like large-numbers of survivors, medical support, light cargo handling, support to other government agencies, etc.. I’d like it to have better weapons capability than the OPC, because this area is still a front line with any issues with former adversaries, but it seems today’s CG doesn’t equip it’s ships with heavy weapons. (I actually think a 57mm and a 25mm are sufficient for this ship, gun-wise, but I’d like to see some torpedo and Sea Sparrow capability – which even the NSC doesn’t have…)

      • Strange how much these look like the “ram” bows that were on ships of the late 19th and early 20th century like the McCulloch or the Olympia ( It would be funny to think that the old guys had it right all along, even if it was for the wrong reason. The other thing I see, is the desirability of having the longest possible waterline without the requirement for the beam strength to support a lot of hull above water at a place where there is minimal hull underwater to float it. (I have to admit I find the “ram” bows more aesthetically pleasing than the X-bow.)

        The ships you have referenced all seem to reflect the Norwegian Coast Guard’s primary focus on ability to do open ocean towing of very large vessels.

        In reference to getting into restricted areas around Alaska, any new cutter would certainly have thrusters, and be much more maneuverability than our previous cutters, particularly if equipped with Azipods.

        Adding Mk 41 vertical launch tubes (VLS) to the NSC along with an associated fire control system has been suggested as a way to make them into a viable alternative to the Littoral Combat Ship. This would have allowed them to fire the Evolved Sea Sparrow Missile, which can be packed four missiles to the tube. It wasn’t that expensive for the capability. Adding the VLS is a relatively low cost way to add a lot of potential for the future since there are a lot of different types of rounds that can be fired from them.

        For additional smaller icebreakers, we could do worse than update the wind class, but the Mackinaw might be as capable–not my area.

      • Well, I’ll go you one better: I think the X-bow is downright ugly, BUT, form follows function, and it clearly is a superior design in heavy seas. Because of the nature of the climate and oceanography of the arctic areas, that capability really cries out for a good design, regardless of how it looks. If I were to suggest a new class based just on looks, I’m with you on the Secretary-class. To my mind, it is/was the most beautiful class of ship ever. When you mention the beam supporting structure above it, I take it you don’t like the high forecastle of the X-bow either? I despise it. I think you mentioned earlier that to avoid green water spilling over, the foc’sle must be a deck or so higher than normal. I think that would be acceptable, but the remaining three or so decks which usually come along on all Ulstein designs, I’d get rid of. That’s why I like the POR design – it seemed to keep enough height in the bow to allow an X-bow while keeping the foc’sle low enough to allow for weapons ahead of the superstructure (whereas Ulstein seems to pile the superstructure atop the bow as far forward as possible, which I do NOT like). One thing about avoiding an icebreaker’s spoon-bow for an arctic patrol cutter (vs. an icebreaker) is that I seem to recall the shape of the Wind-class’ hull caused them to be bad rollers.

        I’ve actually looked to the Norwegian, Icelandic, and Finnish designs because of their regular ice / arctic operational environment. As far as specific capabilities, yes, I thinking towing is important, but it’s certainly not the USCG’s primary operation in the Bering Sea. I think having a good towing capability is important, and I gladly sacrifice the transom boat ramp to retain a good towing bitt at the stern (plus, the double-acting stern profile doesn’t work well with a transom boat ramp anyway). Towing can be vital to the arctic mission. Vessels in danger of running aground and vessels who have lost steerage due to ice or mechanical casualty, are two clear needs for towing which are life/safety risks as opposed to salvage which can be common in D17. Overall, towing is a pretty low priority in my design.

        I very much like where you’re going with the Mk41 idea. There is a slightly shorter version of the Mk41, which would make it suitable for shallower-draught vessels, such as the Arctic Patrol Cutter or the OPC. Here’s a clip from
        “The modular MK 41 is adaptable to short-length configurations to enhance ship and weapon applicability potential worldwide. Responding to continued development interest from US Navy allies, the USN is pursuing a VLS MK 41 tactical-length launcher initiative to provide for shipboard loadout and rapid firing of existing Antiaircraft Warfare (AAW) and Antisubmarine Warfare (ASW) tactical weapon types, and allow significant expansion in alternate ship mounting arrangements (such as in superstructure areas) and for reduced draft hulls. The engineering development for the tactical-length launcher has been completed. The tactical-length launcher uses the vast majority of the strike-length VLS MK 41 components and remains an eight-cell module with full VLS MK 41 system capability.”

        I think Evolved Sea Sparrow, Harpoon, and a follow-on replacement to ASROC would be an excellent round-out of capabilities, but if the Mk.41 is not to be, there’s always the Mk.48 VLS. It would only give the cutters ESSM capability, but that would be enough to make me happy. Also, it’s retro-fittable, so even if not built with it, this capability could easily be added without much work.

        Some 12″ TTs with Mk.54s and a good sonar is an even more important weapon system for the APC, in my opinion. The Bering Sea and Straights are a gateway in and out of the arctic for subs. While this isn’t as important now with the USSR gone and Russian subs not operating much, you never know about China or No. Korea.

      • Bill my reference to beam strength was because the typical design has a lot of hull above water at the bow that is supported by very limited flotation below the water line. This means that the structure has to have the additional beam strength to support that large above water bow that is not supported by flotation directly below. This would be advantage to the X-bow.

        Damen (that provided the parent craft for the fast response cutter) also has a bow designed specifically for heavy weather that they call the “Axe Bow,” looks like a vertical stem with no flare on the bow, so conceptually is a step midway between the conventional raked and flared bow and the X-Bow.

        Think the round bottom, rather than the bow shape was what made the Wind Class (and the old Mackinaw) roll so badly.

        If the Navy would come to their senses on the LCS we might have an opportunity to share development of a true Littoral Combat Ship in terms of a common platform with the OPC.

        With a bit of rearrangement the same basic systems in a bit different hull might serve as the Arctic Patrol Vessel.

  14. Well, I cheated in my layout work. I compared several vessels including the 210s, 270s, the Wind-class, the Mackinaws (old & new), and when looking at sizes and displacement, came up with the numbers above. I was trying to keep the design compact enough for operations in the Aleutians and the Inside Passage. Not to mention that some of the harbors up there are rather tight. (At my dimensions, the design might already be too big in this regard…)

    I’m by no means someone who equates length with cost, but I thought this size would (hopefully) be cheaper to operate than a larger cutter doing the same mission. (I was thinking directly of the 378s & older vessels currently operating in D17; not how it would compare to some other contemporary [new] design.)

    I hadn’t considered the beaminess of my design and whether an x-bow had been used in such a design before. More fun research.

  15. Very interesting discussion regarding the appropriate ship to patrol the arctic. You know, unless we go with something “off-the-shelf”, we run the risk of getting something of a much different than a well thought out design. I believe you called it a “compromise” ship. MACKINAW is one of those ships, and I can tell you that although she is capable, her “one-of” 3.3Mw Azipods are extremely maintenance intensive. Spare parts for the pods require the re-tooling of machinery in Finland and a long waiting period. (The excessive cost does not need to be explained). The Svalbard is equipped with the 5Mw standard “medium sized” azipods with spare parts readily available. These pods have proven to be more reliable than the unique pods in MACKINAW that are generally more difficult to access and repair the internal components. There are numerous other “nuances” associated with operating the unique azipods such as “hydraulic lock”, detent loss of electrical field, etc.

    Directional thrust icebreakers such as MACKINAW are remarkable and in many cases when operating properly, exceed the capability of the traditional diesel-electric shaft-driven breakers. – She can go stern-to and gnaw through the toughest pressure ridges, use her powerful wash to clear ice from trouble areas, and come about rapidly within her own length, for example. I would stick with the Svalbard and change very little, if anything.

  16. Pingback: Canadian Icebreaker, Arctic Offshore Patrol Ship, Shipyard “Rationalization” -

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