Putting Torpedoes on the Webber Class WPC

USCGC Kathleen Moore (WPC-1109)

What is the Problem?:

For a good while, I have been pointing out that the Coast Guard really does not have a means of forcibly stopping a medium to large ship, if its crew is willing to risk death. Even the largest guns the Coast Guard has (76 and 57mm) are unlikely to be able to reliably stop such a ship, and those larger cutters that carry the 76 and 57mm guns are unlikely to be available when needed anyway. They are more likely to be either deployed far from the ports or in maintenance status, unable to respond in a timely manner. There are also no other US military forces positioned and ready to respond to this type threat.

This means, the assets most likely to be available to stop a terrorist attack are Webber class WPCs and smaller vessels. They are armed, at best, with the 25mm M240 chain gun in a Mk38 mount and .50 caliber machine guns. These are even more unlikely to be able to forcibly stop a vessel. In addition there is a good possibility, a hostile vessel used for such a mission could be equipped with weapons that can out gun and out range the cutter. The Mk38 has a reported effective range of 2700 yards. I estimate the maximum effective range of improvised weapons on a terrorist vessel might be as much as 4000 yards. (I have never seen any indication anyone is attempting to train to use anything approaching the 25mm’s maximum range of 7,450 yards.)

Photo: This is a Chinese experiment with improvised armament for civilian ships. Likely useful systems include anti-tank guided missiles, recoilless rifles, heavy machine guns, man portable anti-aircraft missiles, and anti-aircraft and anti-tank guns which are designed to follow fast moving targets allowing them to compensate for movement of the ship. Terrorists would probably make more of an effort to hide the weapons, but you get the idea. 

What is available?:

I believe light weight torpedoes are the lightest, cheapest way to provide the missing capability.

Until recently, I had assumed, we would have to at least reprogram some of our existing light weight torpedoes. Recently I saw a report that the Mk46 mod5 has an anti-surface capability, so it may not be necessary to create or modify a torpedo for the role.

The Mk46 torpedo is not exactly new tech, the original design is over 50 years old and the mod5 version was introduced over 30 years ago. Two newer light weight torpedoes have been developed since introduction of the Mk46, the Mk50 in 1981 and the Mk54 (which uses the propulsion system of the Mk46) in 2004. Because the replacements are more expensive, there are still a large number of Mk46 torpedoes in the inventory. The national fleet (Navy and Coast Guard) has far fewer light weight torpedo armed surface combatants now (85) they did, 30 years ago (229). (At one time, the Coast Guard had quite a few Mk46 torpedoes on the 378s.)

Despite its age, the Mk46 appears adequate to stop most ships. It has an unclassified reported speed 45 knots and a range variously reported as at least 8,000 yards. Its warhead wight is only 98 pounds, about 15% that of the Mk48 heavy weight torpedo’s 650 pound warhead, but the effects of underwater explosions are not proportional to the weight of explosive. The effect, assuming the same explosive is use, is proportional to the cube root of the weight of explosive. This means that the shock experienced as a result of a 98 pounds of explosive underwater is more than half that experienced as a result of the explosion of 650 pounds at the same distance.

We might convince the Navy that putting torpedoes on Coast Guard cutters, is just another place to store them until needed. We are not likely to expend many of them, and if we use one or two, I think they will forgive us.

Why the Webber class WPCs?:

If there is a terrorist attempt using a medium to large ship, a Webber class WPC is likely to be the most capable Coast Guard unit available to attempt to stop the attempt. Larger ships are likely to be either far away or unable to get underway in time.

Perhaps in the future we could also equip the larger cutters and the 87 foot WPB replacement with these weapons, but the WPCs should be the highest priority.

What does an installation look like?: 

American light weight torpedo launchers are all designated Mk32, but they are available in three configurations, triple, stacked twin, and single. The single tube fixed Mod11 is the lightest and probably most appropriate for the WPCs. Two torpedo tubes and two torpedoes are probably sufficient. Support equipment can mostly be left at a support facility ashore.

Surface Vessel Torpedo Tube, Mk32 mod11

These systems are relatively small, 11’4″ in length and less than two feet wide. Loaded with a Mk46 torpedo, each tube weighs 1160 pounds. They do require 9’6″ of open space behind the breech for the tray used to load the 8’6″ long torpedo.

Where to put install?:

In regard to putting torpedoes on Webber Class cutters, one question I have gotten is, “where would you put them?”

I see three likely locations. All three would require some minor modifications to the ship.

  1. On the stern aimed aft to fire over the transom.
  2. On the O-1 deck behind the bridge firing forward and slightly to the sides.
  3. On the O-1 deck forward of the bridge firing forward and slightly to the sides.

The first would require some rearrangement of deck outfit.

The second and third options would likely require about a three foot wide and 12 foot long extension to the O-1 deck on both sides essentially covering the walkway between the main deck superstructure and the side of the hull. This would allow mounting and access to the tubes which would be pointed at a shallow angle outboard placing the muzzle just inside and above the ship’s side. The breech would be angled in so that it is accessible for loading from the clear space behind it.

Personally I prefer the second or third options.

If there is ever a question “Are cutters are large enough to launch a light weight torpedo?” this should dispel any doubts. Below is a photo of a 12 meter (40 foot) Unmanned Surface Vessel with two torpedo tubes. It also has a dipping sonar (presumably the type used by helicopters).

My Unfunded Priority List

An earlier post reported a plea by Representative Duncan Hunter, Chair of the Transportation Subcommittee on Coast Guard and Maritime Transportation, for the Coast Guard to provide an unfunded priority list to include six icebreakers and unmanned Air System.

Thought perhaps I would list my own “unfunded priorities.” These are not in any particular order.

PLATFORM SHORTFALLS

Icebreakers: We have a documented requirement for three heavy and three medium icebreakers, certainly they should be on the list. Additionally they should be designed with the ability to be upgraded to wartime role. Specifically they should have provision for adding defensive systems similar to those on the LPD–a pair of SeaRAM and a pair of gun systems, either Mk46 mounts or Mk38 mod 2/3s. We might want the guns permanently installed on at least on the medium icebreakers for the law enforcement mission. Additionally they should have provision for supporting containerized mission modules like those developed for the LCS and lab/storage space identified that might be converted to magazine space to support armed helicopters.

110225-N-RC734-011 PACIFIC OCEAN (Feb. 25, 2011) Guy Mcallister, from Insitu Group, performs maintenance on the Scan Eagle unmanned aerial vehicle (UAV) aboard the amphibious dock landing ship USS Comstock (LSD 45). Scan Eagle is a runway independent, long-endurance, UAV system designed to provide multiple surveillance, reconnaissance data, and battlefield damage assessment missions. Comstock is part of the Boxer Amphibious Ready Group, which is underway in the U.S. 7th Fleet area of responsibility during a western Pacific deployment. (U.S. Navy photo by Mass Communication Specialist 2nd Class Joseph M. Buliavac/Released)

110225-N-RC734-011
PACIFIC OCEAN (Feb. 25, 2011) Guy Mcallister, from Insitu Group, performs maintenance on the Scan Eagle unmanned aerial vehicle (UAV) aboard the amphibious dock landing ship USS Comstock (LSD 45). Scan Eagle is a runway independent, long-endurance, UAV system designed to provide multiple surveillance, reconnaissance data, and battlefield damage assessment missions. Comstock is part of the Boxer Amphibious Ready Group, which is underway in the U.S. 7th Fleet area of responsibility during a western Pacific deployment. (U.S. Navy photo by Mass Communication Specialist 2nd Class Joseph M. Buliavac/Released)

Unmanned Air Systems (UAS): We seem to be making progress on deploying UAS for the Bertholf class NSCs which will logically be extended to the Offshore Patrol Cutters. So far we see very little progress on land based UAS. This may be because use of the Navy’s BAMS system is anticipated. At any rate, we will need a land based UAS or access to the information from one to provide Maritime Domain Awareness. We also need to start looking at putting UAS on the Webber class. They should be capable of handling ScanEagle sized UAS.

File:USCGC Bluebell - 2015 Rose Festival Portland, OR.jpg

Photo: The Coast Guard Cutter Bluebell sits moored along the Willamette River waterfront in Portland, Ore., June 4, 2015. The Bluebell, which celebrated its 70th anniversary this year, is one of many ships participating in the 100th year of the Portland Rose Festival. (U.S. Coast Guard photo by Chief Petty Officer David Mosley.)

Recapitalize the Inland Tender Fleet: This is long overdue. The program was supposed to begin in 2009, but so far, no tangible results. It seems to have been hanging fire for way too long.

Expand the Program of Record to the FMA-1 level: The Fleet Mix Study identified additional assets required to meet the Coast Guard’s statutory obligations identifying four asset levels above those planned in the program of record. Lets move at least to first increment.

Alternative Fleet Mix Asset Quantities

————–POR       FMA-1      FMA-2      FMA-3       FMA-4
NSC                8             9                 9                 9                  9
OPC              25           32               43                50               57
FRC              58           63               75                80               91
HC-130         22            32               35                44               44
HC-144A       36            37               38                40               65
H-60              42            80               86                99             106
H-65             102         140             159              188            223
UAS-LB           4            19                21                21              22
UAS-CB        42            15                19               19               19

At the very least, looks like we need to add some medium range search aircraft (C-27J or HC-144).

Increase Endurance of Webber Class Cutters: The Webber class could be more useful if the endurance were extended beyond five days (currently the same as the 87 cutters, which have only one-third the range). We needed to look into changes that would allow an endurance of ten days to two weeks. They already have the fuel for it.

MISSION EQUIPMENT SHORTFALLS

Seagull_torpedo_trial_1

Ship Stopper (Light Weight Homing Torpedo): Develop a system to forcibly stop even the largest merchant ships by disabling their propulsion, that can be mounted on our patrol boats. A torpedo seems the most likely solution. Without such a system, there is a huge hole in our Ports, Waterways, and Coastal Security mission.

121211-N-HW977-692

Photo: SeaGriffin Launcher

Counter to Small High Speed Craft (Small Guided Weapon): Identify and fit weapons to WPB and larger vessels that are capable of reliably stopping or destroying small fast boats that may be used as fast inshore attack craft and suicide or remote-controlled unmanned explosive motor boats. These weapons must also limit the possibility of collateral damage. Small missiles like SeaGriffin or Hellfire appear likely solutions.

40 mm case telescoped gun (bottom) compared to conventional guns.

40 mm case telescoped gun (bottom) compared to conventional guns.

Improved Gun–Penetration, Range, and Accuracy: The .50 cal. and 25mm guns we have on our WPBs and WPCs have serious limitations in their ability to reach their targets from outside the range of weapons terrorist adversaries might improvise for use against the cutters. They have limited ability to reach the vitals of medium to large merchant vessels, and their accuracy increases the possibility of collateral damage and decreases their probability of success. 30, 35, and 40 mm replacements for the 25 mm in our Mk38 mod2 mounts are readily available.

Laser Designator: Provide each station, WPB, and WPC with a hand-held laser designator to allow them to designate targets for our DOD partners.

CONTINGENCY PLANNING SHORTFALLS

Vessel Wartime Upgrades: Develop plans for a range of options to upgrade Coast Guard assets for an extended conflict against a near peer.

 

30mm “Swimmer” Round

30x173mm ammunition for Mk44 Bushmaster II

30x173mm ammunition for Mk44 Bushmaster II

Ran across an interesting new type of ammunition, the 30 mm Mk 258 mod 1 APFSDS-T, which appears to be designed specifically to counter Fast Inshore Attack Craft (FIAC). It uses a unique configuration to allow it to maintain high velocity after entering the water. Being an armor-piercing, fin stabilized, discarding sabot, tracer round, I suspect it might help us attack the engine rooms of larger ships. if we upgrade our Mk38 gun mounts to use the 30mm. Might be able to disable propellers and rudders as well.

In a test “…it destroyed a representative FIAC target travelling at 30kts at a range of 4.8km with the first shot.”

It would probably be good against radio controlled boats like the one in the recent attack off Yemen. General Dynamics is advertising that this “swimmer version” is currently available. This might explain why the Navy replaced the 57mm on the DDG-1000 class will 30mm guns. 

There is a bit more in the 2014 NAMMO Bulletin, on page 8 (5/13 on the pdf), under the title “The Navy’s Best Ammunition”;

The nose-shaped configuration was originally patented by the U.S. Navy and NSWC Dahlgren, but was never turned into functional ammunition. Nammo, NSWC Dahlgren and FFI (Norwegian Defense Research Establishment) carried out a comprehensive study that resulted in the final design configuration of the penetrator nose. Today, Nammo’s Mk258 mod 1 ammunition is used on board the LPD-17 and LCS class of U.S. Navy ships. This has significantly increased the fleet’s capability to defeat aerial and surface threats, as well as submerged threats like torpedoes and mines.

At the very least the 110s in Bahrain (or their Webber class replacements–whenever?) probably should have these. I’d like to see them on all the Webber Class WPCs.

Worried about the Size of the U.S. Navy? Rearm the Coast Guard–The National Interest

Navy photo. MH-60R “Knighthawk” helicopters conducts an airborne low frequency sonar (ALFS) operation during testing and evaluation

Navy photo. MH-60R “Knighthawk” helicopters conducts an airborne low frequency sonar (ALFS) operation during testing and evaluation

The National Interest has a post subtitled, “A new challenge for Trump: redefine the U.S. Coast Guard’s defense roles” you might find interesting.

The author, a Coast Guard Officer and Cutterman, wants to see our larger cutters better armed. He recommends specifically, provision for support of the Navy’s MH-60R

“The U.S. Coast Guard should explore adding the ability to embark, operate with, maintain and rearm these aircraft from both the National Security Cutter and Offshore Patrol Cutter. Only complete solutions that see cutters equipped with ordnance handling facilities, surge berthing for a full-maintenance detachment and sensor integration through data links should be considered.”

and the 5″ Mk45 for the National Security Cutter.

“The addition of a true major caliber-deck gun offers immediate utility, but the system’s real potential will be unlocked if efforts to develop hypervelocity projectiles bear fruit. If so, the National Security Cutter would emerge as a true utility warship capable of providing fires to forces ashore at substantial range and meaningfully contributing to air defense.”

070111-N-4515N-509 Atlantic Ocean (Jan. 9 2007) - Guided missile destroyer USS Forest Sherman (DDG 98) test fires its five-inch gun on the bow of the ship during training. The Sherman is currently conducting training exercises in the Atlantic Ocean. U.S. Navy photo by Mass Communication Specialist Seaman Apprentice Joshua Adam Nuzzo (RELEASED)

Atlantic Ocean (Jan. 9 2007) – USS Forest Sherman (DDG 98) test fires its five-inch Mk 45 mod4 gun during training.U.S. Navy photo 070111-N-4515N-509 by Mass Communication Specialist Seaman Apprentice Joshua Adam Nuzzo

He does, however, see the services culture as an impediment.

“The lesson of the twenty-five years following the Hamilton experience is that a challenge to maintaining the U.S. Coast Guard’s warfighting capability lies in managing the service’s perception of its character…

He also notes that previous concepts of the Coast Guards wartime environment may be unrealistic.

“Attempts to define the U.S. Coast Guard’s defense roles following the Cold War have been challenging. Published in 1998, Coast Guard 2020 proclaimed that the “Coast Guard will be prepared to operate in low-threat conflict environments, and to provide specialized functions at all levels of operation.” The notions of low-threat operations and service-unique specialization are obstacles to interoperability. While U.S. Coast Guard buoy tenders and icebreakers absolutely provide specialized capability, the major cutter fleet’s warfighting role was never—nor should it have ever been—unique to the U.S. Coast Guard. Rather, the major cutter fleet provided an active augmentation force trained and equipped to provide service in any theater of war. This should be the target for the fleet’s future employment as the community of nations returns to its more normal mode of great power competition. As for the limitation of a low-threat environment, U.S. Coast Guard cutters have deployed recently to Southeast Asia, the Black Sea, the Arctic and the Arabian Gulf. Saber rattling among great powers and the HSV-2Swift incident demand that we ask: which of these locations will qualify as a low-threat environment on the first day of a global or major regional war?

Generally I agree with the thrust,

“The immediate challenges are acquiring and integrating combat systems and training crews in their employment. These are not trivial tasks and will necessarily consume time and resources. Better to act with dark clouds forming on the horizon, however, than in the midst of the storm.”

It is a two page post. The first page is mostly history lesson on the Coast Guard’s participation in past conflicts, but if he gives the impression the Coast Guard was historically ready for these roles on day 1, that would be a mistake. The Coast Guard entered WWII terribly unprepared. The cutters had no sonar or radar and no depth charge racks. There is nothing new about our current lack of readiness for war, it is not the exception, it is the norm.

Trouble is, we tend to have a binary approach. Either we are at peace and could care less about war-time roles, or we are all in after an attack. We need a more measured approach that responds to changing circumstance.

We really need to do better at preparing for a transition from peace to war. 

I don’t necessarily think removing the ASW systems from the 378s following the collapse of the Soviet threat was a mistake. It was a rational response to rapidly changing circumstance. Since then, we have had a quarter century without a substantial ASW threat, and the 378s are now on their way out. We probably should have removed the CIWS too, unfortunately it did mean we lost all the Coast Guard’s accumulated expertise in ASW. Hopefully we can rebuild it with the Navy’s help if needed.

But circumstances have changed again.

To me, a major conflict now appears more likely in the next ten to twenty years than at any time since I entered the Academy in 1965. We have a true peer challenger, with a chip on its shoulder and a belief in its inherent right to rule, in China. If that was not enough, Russia is rearming and acting increasingly obnoxious. Iran and North Korea may be annoying, but they are really not in the same league, at least in terms of a naval threat. Dealing with them would not stress our Navy, so would not really require Coast Guard assistance. China is the real threat, and if Russia sides with them, things could get dicey. Even without the Russians, the Chinese are building credible surface combattants at least as fast as the US. They already have a local superiority in the Western Pacific. We have to spread our fleet out, while they can concentrate their forces. To concentrate our forces in the Western Pacific, the US will be fighting at arm’s length with long vulnerable supply lines.

I don’t necessarily think war with China inevitable, but we need to recognize the possibility and plan for it.

Theoretically the process should start with an agreement between the Navy and the Coast Guard about what the Coast Guard, particularly its vessels and aircraft, will do in a general war. I see few indications that is happening. Certainly the OPC Concept of Operations did not include anything beyond a simple contingency operation.

I may be wrong about this, since I am way out of the loop, but if the service had an established general war mission focus to prepare for, it should be generally known. It should be reflected in our procurements. Perhaps the Navy thinks it would be presumptuous of them to assign the Coast Guard missions, and the Coast Guard does not want to push itself into Navy planning, but this is too important for delicate feelings to get in the way. Right now the Coast Guard is probably proportionately larger compared to the Navy than at any time in the last 100 years. When I entered the service, the Navy was 22 times larger than the Coast Guard in terms of personnel. Now it is only eight times larger. A combat ready Coast Guard may be the difference between victory and defeat.

Plans:

The Coast Guard has potentially important roles to fill in any general conflict. If the Navy cannot envision these roles, perhaps the Coast Guard should think for itself. Plans should include our aircraft as well as our vessels, but I will stick to the vessels for now.

What we need is not an overall strategy to defeat China, but a well developed range of options for employment and a good idea of what upgrades would be required.

In a major war, I see a major shortfall in open ocean escorts. Thirty years ago, when the threat was the Soviet Navy and the problem was projecting American power across the shorter distances of the Atlantic, the US had 36 cruisers, 69 destroyers, and 115 frigates (plus 12 WHEC 378s). Now they have 22 cruisers, 63 destroyers, and 8 LCS.

Then we had the advantage, that the Soviet Fleet was split into four parts and their egress to our supply lines was limited by the presence of powerful European Allied navies that restricted their access to our supply lines.

In a Pacific War with China, the distances are much greater, our allies fewer, and, with the exception of Japan and S. Korea, much weaker. Our Navy’s fleet, currently 274 ships, with ambitions of 355, is scattered across three oceans while China’s fleet, likely soon to be 500 ships, is geographically concentrated.

If we needed over a hundred frigates to cross the Atlantic, we probably need at least that many to push across the Pacific. As it is, the Navy cannot meet their current peacetime commitments, and replenishment ships cross the oceans unescorted and unarmed.

The Navy seems to have belatedly recognized this with moves toward a new frigate to be based on one of the LCS designs, but even if they complete all 52 small surface combattants currently planned, less than half will be completed as frigates, and if based on the LCS designs, they will have limited range, survivability, and crew size. The Independence class LCS will likely be permanently employed as mine countermeasures (MCM) vessels (There were 22 of those in 1987). The Freedom class will likely be employed in enforcing a blockade (perhaps with help from Webber class WPCs). Even with some backfitting of LCS  25-32, that leaves at most 28 frigates in the current plan. 35 ASW equipped cutters could make a huge difference.

The Cutters:

Cutters should be designed with wartime roles in mind, even if they will not be initially fully equipped with combat systems.

In the Bertholf class and Offshore Patrol Cutters, we will have most of the elements of modern warships. To not be prepared to add the few systems necessary to make them effective warships, if the nation were engaged in combat, would be criminal. If we do not already have plans to upgrade the Bertholf class National Security Cutters and the Offshore Patrol Cutters to give them significantly improved ASW, AAW, and ASuW capability we should start those plans.

At some point perhaps we should prototype an installation of these capabilities on at least one NSC and one OPC. Then we need to wring them out by deploying with the Navy and getting feedback on their performance, and periodically update plans for mobilizing their war-time potential.

The People: 

Just as we have marine inspection, fisheries, and drug enforcement specialist, the Coast Guard needs a cadre of officers in the Office of Counter Terrorism and Defense Operations Policy (CG-ODO) who have a deep understanding of the needs of modern naval warfare, who will advocate for naval capabilities consistent with both wartime missions and the Ports, Waterways, and Coastal Security (PWCS) mission. Likely this means revival or strengthening of officer exchange programs, Tactical Action Officer training, and War College education.

Perhaps the longest lead time item in mobilizing the Coast Guard for war would be the senior enlisted we would need for rating not currently found in the peacetime Coast Guard. It might be possible for the Navy to identify some reservist to augment the crews of Coast Guard cutters upon mobilization, but even a small cadre within the Coast Guard, founded on prototyping systems on at least a couple of cutters would provide valuable continuity and advice in defining required capabilities.

Bottom Line–When we get in trouble, we cannot make it up as we go along. Sweat now, saves blood later.

Thanks to Lyle for bringing this to my attention.

The Mk38 and Ballistics and Weapons Effectiveness Lessons from Pursuit of the Graf Spee, Part 2

 

Part one recounted an engagement in 1939 between the “pocket battleship” (heavy cruiser) Admiral Graf Spee and three smaller British cruisers. This part will discuss the implications.

So what does a 77 year old Naval battle have to do with the Coast Guard’s ability to stop a terrorist attack using a medium to large ship?

As I said in part one (in a different order), I think it shows:

  • It is very difficult to sink a ship by gunfire alone.
  • Ships’ structure provide a degree of protection that makes it difficult to comprehensively target the crew of a ship without sinking the ship.
  • It is difficult to forcibly stop a ship with gunfire alone.
  • In comparing guns, at any given range, the longer ranged weapon generally enjoys an advantage in accuracy.
  • You can run out of ammunition before you accomplish your mission. The depth of your magazine may be important.

What do we have to oppose this type of attack?:

We don’t really have a lot of options.

If we have enough warning, say 24 hours, we can ask for help, but as far as I can tell there is no system of rapid response to surface threats. (When 9/11 occurred, we had no system for rapid response to air threat.) Unless we have absolute proof that the vessel in question is hostile, the Coast Guard would almost certainly have to intercept the vessel to determine hostile intent before it could be attacked. If the threat is a 20 knot ship detected 200 miles from its target we will have only ten hours to deal with the threat, and we are likely to be considerably less.

We have one Maritime Security Response Team (MSRT) on each coast, but to mobilize them, brief, organize, transport, and then get them to where we want them to act may take considerable time. Additionally while they might be effective in retaking a hijacked merchant ship, where there are relatively few hostiles who also have to control the crew, attempting an opposed boarding of a ship crewed by armed terrorist as a first step toward stopping an attack may be suicidal. If we have time to get them into place then perhaps we would also have time to get help from other services.

I think it more likely we will have at best a few hours to deal with the threat and we will have to use forces already in the area. I’ve made suggestions about additional equipment we might use to address this threat (here and here), but this time I will discuss tactics using what we have, or plan to have, and limit equipment suggestions to minimal upgrades and choice of ammunition.

While I doubt we will have cutters armed with 57mm Mk110s or 76mm Mk75s, on scene when required, we will discuss their utility and limitations. The Mk38 seems to be the key system, widely available and potentially capable, if the right ammunition is available. Other systems, .50 caliber and smaller, appear ineffective in stopping medium to large ships, but they may have their uses.

It is very difficult to sink a ship by gunfire alone:

Each of the Graf Spee’s 11.1″ projectile weighed 125 times the weight of a 57mm shell or roughly the weight of all the projectiles in a 57mm Mk110 gun mount’s 120 round automatic feed system.

Graf Spee was hit 20 times, three times by 8″ and 17 times by 6″ for a total of 2,672 pounds of projectiles. That is roughly the equivalent of being hit 500 times by a 57mm. From a distance, other than the burned out scout plane she carried, it would have been difficult to tell that she had been hurt.

Exeter was hit at least seven times excluding damaging near misses. That was 4,627 pounds of projectiles, a weight, I believe, almost equal to the total weight of all the 57mm projectiles allowed on a National Security Cutter (about 5,300 pounds assuming 1,000 rounds). While heavily damaged, Exeter was still capable of making 18 knots and completing the approximately 1,000 nautical mile journey to the Falklands.

Neither of these ships would be considered large by current standards. We can conclude, we are unlikely to sink a medium to large merchant ship with any weapon in the Coast Guard inventory.

Ships’ structure can provide a degree of protection that makes it difficult to comprehensively target the crew of a ship without sinking the ship.

Personnel Casualties were relatively light. Out of the approximately 3,000 men on the four ships, there were only 108 killed and 88 wounded.

  • Commonwealth: 72 dead (Achilles 4, Ajax 7, Exeter 61), 28 wounded
  • Germans: 36 dead, 60 wounded

As severely damaged as Exeter was, less than one in ten of the crew was killed. Unless terrorists choose to expose themselves, gunfire, from either cutters or airborne use of force equipped helicopters, is unlikely to allow us kill enough terrorists to stop an attempt to use a medium or large ship to make an attack.

Can We Immobilize the Target?: 

None of the four ships were immobilized.

Of the approximately 30 hits, only one hit a main machinery space and it appears this was not because armor kept rounds out. It was simply that the amount of machinery space above the water line is a very small percentage of the total exposed area.

The single projectile that entered a machinery space was an armor-piercing 8″ round, and it wrecked the Graf Spee’s fuel oil purifier.  That made it virtually impossible for the ship to make it back to Germany without having work done in port over an extended period. That would have allowed Britain to guarantee that Graf Spee would never escape, but it did not stop her from transiting at full speed for about 14 hours.

A modern merchant vessel diesel engine. 

The task of stopping a ship by gunfire actually may have become more difficult because of the size and toughness of modern large diesel power plants, and because the large size of modern vessels puts more of the engine below the waterline and provides more space between the ships sides and the propulsion machinery.

The ship featured in the video above is no longer particularly large. The new Panama Canal locks needed to be wider and deeper than the old ones to accommodate the larger ships that have now become common. The locks are now 180 feet (vs 110 feet) wide and 60 feet (vs. 42 feet) deep. Many ships now have sufficient draft such that the 40 foot tall engine in video could be entirely below the water line.

Fuel consumption for the engine in the video above was reported twice, first as 328 tons per day and later as 400 tons per day. If we assume only 300 tons per day, that is 12.5 tons per hour or 417 pounds /minute or about 7 pounds per second.

The explosions going off in this type of engine every second are more powerful than the explosion of a 57mm shell. 

There is less than a pound of explosive in a 57mm projectile. 1 pound of TNT has 13.4 megajoules of energy. We may assume a more powerful explosive in the Mk110 projectiles, perhaps 20 megajoules. One gallon (about 7.1 pounds) of diesel (the amount consumed in one second) equals 146.5 megajoules.

The 57mm gun does not have a true armor-piercing round. The current 3P fuse has a semi-armor piercing function which I presume is similar to the previous semi-armor piercing (SAP) round, “The SAP round had a delayed action fuze which allowed the round to penetrate about 2 cm (0.8 inches) of armor and then explode after traveling a further 2 m (6 feet).” If that is the case, first it is uncertain that the round will penetrate, since the plating on large ships can considerably exceed 2 cm, but assuming it did, an explosion two meters inside the hull would still be a long way from a very tough engine.

The 76mm Mk75 is the most powerful gun in the Coast Guard inventory, but we have fewer of them every year, although it looks like we will not see the last of those on the 270s until 2034. It is still a relatively small projectile at about 14 pounds. Like the 57mm there is no true armor-piercing round for this weapon. Like the 57mm its projectile would likely explode shortly after penetrating the hull, rather than on or in the engine. The 57 and 76 mm guns might have more success against the steering gear, but that will also be very robustly built on any large ship, and hitting it will require great accuracy, suggesting a close approach.

The Mk38 25 mm, with a maximum shell weight of 1.1 pound or less, might be assumed to be even less likely to do damage, but they do have an option for an armor-piercing fin stabilized discarding sabot round (APFSDS) (pdf). It is intended for use against lightly armored vehicles like Armored Personnel Carriers. It may not be commonly available for the Mk38 (the Navy thinks of the Mk38 exclusively as a counter to small craft), but the APFSDS round is in the Navy system for use by Marine LAV-25 Light Armored Vehicle. It fires a 98 gram (3.5 oz) Solid Tungsten Penetrator at a very high velocity, 1390 m/sec (4560 ft/sec).

25MM TUNGSTEN APFSDS-T Armor Piercing Fin Stabilized Discarding Sabot-Trace

25MM TUNGSTEN APFSDS-T
Armor Piercing Fin Stabilized Discarding Sabot-Trace

The .50 caliber, 7.62 and 5.56 mm weapons are simply too light to make much impression on a medium or large ship. The only other CG gun with a possibility of forcibly stopping one of these vessels is the Phalanx 20mm Close In Weapons System (CIWS). This system uses a discarding sabot round 12.7mm in diameter Solid Tungsten Penetrator with a 3,650 fps (1,113 mps) muzzle velocity. The Phalanx is only found only on WHECs and NSCs, so they will soon be home ported only in Charleston, Alameda, and Honolulu and it is unlikely these ships will be available to respond.

If we do detect a terrorist attack, the only likely Coast Guard counter to it, is likely to be equipped with a Mk38 mount. We are not going to sink a medium or large ship with the Mk38, but we might be able to disable it, if we can accurately penetrate both the ship’s hull and the ship’s engines or disable the steering.

In comparing guns, at any given range, the longer ranged weapon generally enjoys an advantage in accuracy.

I started thinking about the results of the Battle of River Plate after reading this pdf, Offshore Patrol Cutter (OPC) SUW Self-Protection Secondary Battery Study (which compared one and two-gun solutions using .50 cal., 25mm, and 30mm) and writing a post about a possible 40mm alternative for the Mk38 gun mount currently used on the Webber class WPCs and planned for the Offshore Patrol Cutter. It occurred to me that everyone may not understand my strong preference, when considering guns, for the longest ranged weapon available, even if I don’t expect it to be used at extreme ranges.

It is not just the potential of longer range, or the fact that the projectile is probably larger and more effective. It is also the fact that, all other factors being equal, the longer ranged weapon is also almost always more accurate.

Comparing any two weapons, fired at a target at the same range, the longer range weapon will generally fly a flatter trajectory (a more direct path) and have a shorter time of flight, meaning it will be effected less by uncertainties of environment and the actions of the target between firing and impact.

In the battle we see three gun with different ranges and can compare their accuracy. If we look at the British 6″ guns as a base line, how did the weapons compare?

The British 6″ gun had a maximum range of  24,500 yards (22,400 m). They got hits 0.82% of the time.

The British 8″ gun had a maximum range of 30,650 yards (28,030 m), 25% greater range, got hits 1.55% of the time, making them 89% more accurate than the contemporary 6″ guns.

The German 11.1″ had a maximum range of 39,890 yards (36,475 m), with 63% greater range than the 6″ guns, got hits 2.4% of the time, making them almost three times as accurate as the 6″ guns at the ranges the battle was fought (193% more accurate).

While it might be argued that the Graf Spee benefitted from superior fire control, the same cannot be said for the Exeter’s 8″ guns, that for most of the engagement were fired under local control. Additionally it appears that the light cruisers’ director controls were at least as sophisticated as that on Exeter. It appears the greater accuracy is due to the flatter trajectory and shorter time of flight of the longer ranged guns.

40 mm case telescoped gun (bottom) compared to conventional guns.

40 mm case telescoped gun (bottom) compared to conventional guns.

There are at least four different gun calibers that can be mounted on the Mk38 gun mount, 25, 30, 35, and 40mm. If we have the opportunity to upgrade the Mk38s to higher caliber weapons, we should take it, not just for the greater effectiveness of the projectile but also for the likely greater accuracy and effective range.

 

 

 

Case Telescoped 40 mm ammunition

Case Telescoped 40 mm ammunition

Making the Best of the Mk38

“No captain can do very wrong if he places his ship alongside that of the enemy.”–Horatio Nelson

When I looked at this problem earlier, I suggested that we should have systems that could disable a ship at ranges greater than 4,000 yards, so that weapons on the terrorist controlled vessel could not target specific systems on the defending cutter. With what we have now, we don’t really have that option. We are going to need to get a lot closer.

Not only is the effective range of the Mk38 less than 4,000 yards, we will need to get closer to increase accuracy to target specific parts of the terrorist vessel, and close the range to maximize the kinetic energy of the rounds.

If we are to have any chance of stopping a medium to large ship making a terrorist attack, we need to do what the British did. We need a team approach. We need to gang up on it.

The only ships we have that might have a chance are those with 25mm and larger weapons. There are relatively few of those. They would be the primary shooters. Hopefully you would have more than one to respond, but in many cases, perhaps most, there would be only one.

We can still use less capable units to take pressure off the primary shooter. These supporting units equipped only with .50 caliber and smaller weapons might be used to target the bridge, but their primary function should be to target any weapons that might endanger the more capable cutter(s). 

Targeting the bridge is relatively simple, but if the terrorists plan properly they will not need to navigate from the bridge. They can use an autopilot or steer from after steering.

As we approach we will want to establish hostile intent as early as possible, preferably without putting a boarding party aboard that might become hostages.

We can demand that the vessel stop or change course away from the endangered potential target. The quickest way to do that might be with an Airborne Use of Force helicopter. Other supporting units might also be sent ahead of the primary shooter to attempt to stop or turn the suspect vessel.

After establishing hostile intent, supporting units should, if possible, precede the primary shooter and engage the threat with the idea of suppressing any weapons the vessel might employ against the cutters.

As it approached its target, before attempting to disable it, the primary shooter should probably put a few rounds into the bow of the target, in case it has been loaded with explosives.

Because the supporting units will need to stay out of the line of fire between the primary shooter and terrorists’ vessel, and because projectile will lose the minimum amount of kinetic energy if it strike normal to the target’s side, the primary shooter should move to a position on beam of the threatening vessel, while supporting units should be both forward and aft of the primary shooter’s line of fire, ready to engage any attempt to return fire.

If the supporting units include a unit with only one machine gun on the bow, like a Response Boat, Medium (RB-M) and a unit with machine guns both fore and aft, like an 87 foot WPB, the WPB should be positioned toward the bow of the target, so that it can parallel the target and still have weapons on target while the unit (RB-M) with only gun on the bow, can keep its weapon on target.

An airborne use of force helicopter could also be very useful as a supporting unit, taking out any terrorist who appeared on deck and keeping an eye out for their activities on the disengaged side of the vessel.

At some point the primary shooter is going to have to close alongside, so that it can shoot through the hull near the waterline, down and into the engine room below the waterline. The supporting units should get there first, shoot up the bridge, attempt to draw fire and suppress any return fire.

When the primary shooter comes alongside ready to attempt to disable the terrorist vessel it will need a lot of ammunition so it will need to exercise fire discipline during the approach.

If we are unable to disable the engine(s) or steering, as a last ditch effort, we can attempt to push the vessel into shoal water and run it aground. This would of course make the cutters easy targets for grenades and RPGs.

Conclusion: 

The approach outlined above implies a desperate fight, with no guarantee of success. If the terrorists manage to knock out the few (or one) weapon capable of stopping them, we might have no chance of success.

This is not the kind of fight the Coast Guard should want. It puts our people, our mission, and the people we are supposed to protect in danger. Right now there is no assurance that 25mm can even do the job.

We really ought to do better.

The Future:

I would hope the Coast Guard would do some testing to find out if we have the weapons we need to stop the full range of possible maritime terrorist attacks.

That should help us pick the right ammunition. We really need to make sure we have the right types. of ammunition. 

If tests show we cannot disable the largest ships, we need to insist that get weapons that can, and they may not be standard US Navy weapons.

Alternately, we need to establish means to have other services deploy anti-ship weapons on short notice. (Coast Defense is still officially an Army mission.)

We noted earlier that a new Mk38 mod3 mount is on the way.  It will have much more ammunition on the mount. While the mount appears designed for a 30mm gun, it appears we will be getting them equipped with 25mm guns. More ammunition is good, but a larger weapon would be better.

Guns may not be the answer, but any upgrade we can get in the caliber of the gun on the mount will permit it to be more effective against progressively larger ships and at longer range.

In the not too distant future we will need to start replacing the 87 foot Marine Protector class WPBs. The oldest are already 18 years old. As soon as the last Webber class is funded, we need to start funding 87 footer preplacements. Hopefully we will see fit to arm these vessels for this mission.

 

 

Navy Rethinks the LCS–Manning, Crew Rotation, Homeporting

800px-USS-Freedom-rear-130222-N-DR144-367

Photo: USS Freedom (LCS-1)

The US Naval Institute news service reports “Results of New LCS Review is Departure from Original Vision.”

Why should we care?:

For one thing the LCS were planned to be multi-crewed. Their plan was a bit different from our Crew Rotation Concept, but the idea was the same, multiple crews rotating among multiple ships to provide more deployed time. The Coast Guard had planned to apply the Crew Rotation Concept to the National Security Cutters, but I have also seen it referred to with regard to the Offshore Patrol Cutters.

Earlier I called the Offshore Patrol Cutter, the other LCS, and it does look like they will continue to share some systems and training. If the OPCs emerge with space for modular systems, we may see even more cross talk between the programs. The two types (LCS and OPCs) are similar in size, so comparisons are inevitable.

Hopefully we can learn from their experience.

The results: 

The Navy is abandoning their planned rotation of three crews among two ships in favor of a plan that would assign two crews to a single ship, much like the way SSBNs are manned by blue and gold crews. The significant difference is that the crews “own” the ships, they don’t expect to walk away to a different hull and never see it again.

The size of the crews is to be increased. Originally there was to have been a core crew of 40. That was increased to 50, and it is now planned to increase the core crew to 70 plus a 23 person air detachment. Maximum berthing is reportedly 98. Adding a CG LE team should max out the berthing. This pushes the crew much closer to what the Coast Guard was planning for the OPC, (pdf) a crew of 104. That means a full crew for each LCS is really 163, two core crews of 70 and 23 in the air detachment.

Instead of basing a mix of both types of LCS on each coast, the new plan would put the trimaran Independence class, with its longer range, on the West Coast (San Diego) while the shorter legged, monohull Freedom class will be based on the East Coast (Mayport, FL). That makes a lot of sense.

The ships will be organized into six four ship divisions with each division assigned a single mission (mine countermeasures, anti-surface, or antisubmarine). The four oldest ships will be single crewed, will not be assigned to a division and will instead be used for training and testing. Again this makes sense since subsequent ships are somewhat different, having incorporated lessons learned on the first ships.

That doesn’t necessarily mean there will be one division of each class assigned each of the three missions although that may the result. To me the Independence class appears better suited for ASW and the Freedom class by default better used as minecountermeasures ship.

uss_independence_lcs_2

Photo: USS Independence (LCS-2), U.S. Navy photo by Mass Communication Specialist 2nd Class Justan Williams 

Lessons: 

When the Coast Guard finally decides to abandon the Crew Rotation Concept, as currently envisioned–four crews for three ships. They can point to the LCS experience as justification.

As a means to allow increased time underway, permanently augmenting the NSCs’ crews to allow generous leave and TAD assignments is probably a better solution. After all, if we have a crew of 160 or so assigned to each NSC or OPC, we could probably keep them underway at least as much as the LCS are.

Applying a division staff organization to the NSCs and perhaps the OPCs is probably a good idea. In addition to a post command captain, that could, among other things, provide initial advice to newly arrived COs and possibly a relief CO function; it could provide personnel augmentation for those specialists positions that have little or no redundancy in the typical ship’s organization, allowing them some leave and/or TAD while the ship is underway, with the objective of keeping the crew members underway time at 185 days or less, while the ship is away from homeport for a considerably longer time.

More on the Navy’s New Design for Maintaining Maritime Superiority

Waesche Carat 2012

This is a post I wrote for CIMSEC. under the title “A Design for Maintaining Maritime Superiority”–A Coastie’s View.” It is an expanded version of an earlier post that appeared here. The rewrite really begins about half way down under the header, “What I Want to See.”

Recently the new Chief of Naval Operations issued a document “Design for Maintaining Maritime Superiority” that outlines how, hopefully, the US Navy can maintain a maritime superiority our foes will recognize and avoid confronting.

If you look for anything specifically regarding the Coast Guard here, you will not find it (other than the cutter in the formation on the cover). The Coast Guard is not mentioned even once, but it does talk about some things that are Coast Guard related. Perhaps the Coast Guard should not feel bad about this. It only mentions the Marine Corps once.

Three Forces that are Changing the Environment

  • The first global force is the traffic on the oceans, seas, and waterways, including the sea floor – the classic maritime system.
  • A second increasingly influential force is the rise of the global information system – the information that rides on the servers, undersea cables, satellites, and wireless networks that increasingly envelop and connect the globe.
  • The third interrelated force is the increasing rate of technological creation and adoption.

Obviously the Coast Guard facilitates and regulates marine traffic, and is tapped into the global information system. In wartime, these contacts will become essential since they will form the basis for naval control of shipping. He also talks about new trade routes opening in the Arctic. These will only be reliable if we have new icebreakers. He also talks about illegal trafficking.

“This maritime traffic also includes mass and uncontrolled migration and illicit shipment of material and people.”

A Document That Explicitly Recognizes the Competition

“For the first time in 25 years, the United States is facing a return to great power competition. Russia and China both have advanced their military capabilities to act as global powers. Their goals are backed by a growing arsenal of high-end warfighting capabilities, many of which are focused specifically on our vulnerabilities and are increasingly designed from the ground up to leverage the maritime, technological and information systems. They continue to develop and field information-enabled weapons, both kinetic and non-kinetic, with increasing range, precision and destructive capacity. Both China and Russia are also engaging in coercion and competition below the traditional thresholds of high-end conflict, but nonetheless exploit the weakness of accepted norms in space, cyber and the electromagnetic spectrum. The Russian Navy is operating with a frequency and in areas not seen for almost two decades, and the Chinese PLA(N) is extending its reach around the world.

“…Coupled with a continued dedication to furthering its nuclear weapons and missile programs, North Korea’s provocative actions continue to threaten security in North Asia and beyond.

“…while the recent international agreement with Iran is intended to curb its nuclear ambitions, Tehran’s advanced missiles, proxy forces and other conventional capabilities continue to pose threats to which the Navy must remain prepared to respond.

“…international terrorist groups have proven their resilience and adaptability and now pose a long-term threat to stability and security around the world.”

Recognizing Budgetary Limitations

“There is also a fourth ‘force’ that shapes our security environment. Barring an unforeseen change, even as we face new challenges and an increasing pace, the Defense and Navy budgets likely will continue to be under pressure. We will not be able to “buy” our way out of the challenges that we face. The budget environment will force tough choices but must also inspire new thinking.”

Throughout there is an emphasis on understanding history and the strategic concepts of the past. There is also a recognition of the need to work with partners.

“EXPAND AND STRENGTHEN OUR NETWORK OF PARTNERS: Deepen operational relationships with other services, agencies, industry, allies and partners – who operate with the Navy to support our shared interests.”

Other than the Marine Corps, the US Navy has no closer partner than the US Coast Guard. And while only about one eighth the size of the US Navy, in terms of personnel, the US Coast Guard is larger than Britain’s Royal Navy or the French Navy. The partnership has been a long and successful one, but I would like to see the Navy be a better partner to the Coast Guard. This is how the Navy can help the Coast Guard help the Navy.

What I Want to See

If we have a “run out of money, now we have to think” situation, one thing we can do is to try to get the maximum return from the relatively small investment needed to make the Coast Guard an effective naval reserve force.

WPC Kathleen_Moore

We need explicit support from the Navy at every level, particularly within Congress and the Administration, for Coast Guard recapitalization. While the Navy’s fleet averages approximately 14 years old. The Coast Guard’s major cutters average over 40. The proposed new ships, are more capable than those they replace. They are better able to work cooperatively with the Navy. The nine unit 4,500 ton “National Security Cutter”program is nearing completion with funds for the ninth ship in the FY2016 budget. The 58 unit, 154 foot, 353 ton Webber Class  program is well underway with 32 completed, building, or funded. But the Coast Guard is about to start its largest acquisition in history, 25 LCS sized Offshore Patrol Cutters. Unfortunately, it appears that while the first ship will be funded in FY2018 the last will not be completed until at least 2035. This program really needs to be accelerated.

We need an explicit statement from the Navy that they expect the Coast Guard to defend ports against unconventional threats, so that they can keep more forces forward deployed. This is in fact the current reality. The Sea Frontiers are long gone. Navy vessels no longer patrol the US coast. The surface Navy is concentrated in only a handful of ports. No Navy surface combatants are homeported on the East Coast north of the Chesapeake Bay. If a vessel suspected of being under the control of terrorists approaches the US coast the nearest Navy surface vessel may be hundreds of miles away.

We need the Navy to supply the weapons the Coast Guard need to defend ports against unconventional attack using vessels of any size, with a probability approaching 100%. These should include small missile systems like Hellfire or Griffin to stop small, fast, highly maneuverable threats and we need a ship stopper, probably a light weight anti-ship torpedoes that target propellers to stop larger threats. We need these systems on not just the largest cutters, in fact they are needed more by the the smaller cutters that are far more likely to be in a position to make a difference. These include the Webber class and perhaps even the smaller WPBs.

We need to reactivate the Coast Guard’s ASW program and ensure that all the new large cutters (National Security Cutters and Offshore Patrol Cutters) have an ASW capability, if not installed on all of the cutters, at least planned, prototyped, tested, and practiced on a few ships (particularly in the Pacific). The National Security Cutters and the Offshore Patrol Cutters are (or will be) capable of supporting MH-60R ASW helicopters. Adding a towed array likeCAPTAS-4 (the basis for the LCS ASW module) or CAPTAS-2 would give them a useful ASW capability that could be used to escort ARGs, fleet train, or high value cargo shipments. Towed arrays might even help catch semi-submersible drug runners in peacetime.

IMG_4128

The Coast Guard is the low end of America’s Naval high-low mix. It is a source of numbers when numbers are needed. The Coast Guard has more assets for low end functions like blockade than the Navy. The Navy has about 105 cruisers, destroyers, LCS, PCs, and is not expected to have more than 125 similar assets for the forseeable future. The Coast Guard has about 165 patrol cutters  including 75 patrol boats 87 feet long, about 50 patrol craft 110 to 154 feet in length (58 Webber class WPCs are planned), and about 40 ships 210 foot or larger that can be called on, just as they were during the Vietnam War, when the Coast Guard operated as many as 33 vessels off the coast in support of Operation MarketTime, in spite of the fact that the Navy had almost three times as many surface warships as they do now. The current program of record will provide 34 new generation cutters including nine 4500 ton National Security Cutters and 25 Offshore Patrol Cutters that should be at least 2500 tons.

The Coast Guard provides peacetime maritime security, but is currently under-armed even for this mission. A small investment could make it far more useful in wartime.

(Note there is another post on this looking at the “design” from a Navy point of view.)