Video: Northrop Grumman Showcases Very Light Weight Torpedo At Sea Air Space 2021″ –Naval News

Our friends at Naval News have an update on the Very Light Weight Torpedo program. It seems to be progressing rapidly. Apparently this is seen as an urgent requirement.

The discussion in the video talked about the anti-torpedo and anti-submarine capabilities, but no discussion of use against surface targets. I suspect this is because those capabilities are the primary selling points for the Navy. It may not be that it is incapable of attacking surface vessels, which should be easier targets.

We talked about this weapon earlier, in greater depth, including potential Coast Guard use.

Full scale production should drive to price down to a point, it might even find its way into the Coast Guard.

(There does seem to be an error in the written portion of the Naval News post in that it says the diameter of the weapon is 121 mm while the video discussion indicates 171 mm. The figures I had seen earlier were:  6.75″ in diameter (171.45mm), about 85″ in length, and weighs about 220 pounds or about 100 kilos).


“Euronaval 2020: Black Scorpion small-size torpedo from Leonardo” –Navy Recognition

Black Scorpion small-size torpedo from Leonardo (Picture source Leonardo)

We saw this earlier but Navy recognition has another report on the Leonardo Black Scorpio, a truly very small torpedo, 127mm (5″) in diameter and 1.1 meters (43.3″) in length. The report provides a bit more insight into how it is expected to be used.

Much as I see the need for the Coast Guard to have a light weight torpedo, this may be too small to have anything more than very limited utility. A 21″ (533mm) heavy weight torpedo is 80-100 times heavier. A 12.75″ (324mm) light weight torpedo is 11 to 12 times larger. Even Grumman’s “Common Very Light Weight Torpedo” is five times as large.

But I am still curious. Range? Speed? Sensor range? Usable against surface ships? Midget submarines? Moored mines?

Graphic from Leonardo



SAAB’s Light Weight Torpedo

Dmitry Shulgin reports the successful testing of a new light weight torpedo from SAAB that offers some unique feature un-available on US Navy light weight torpedoes.

While American light weight torpedoes are explicitly anti-submarine weapons that at least, in the case of the Mk46 mod5, might have an incidental anti-surface capability, these are expressly identified as being for both anti-submarine and anti-surface use. Unlike USN light weight torpedoes, it has the option of wire guidance. It is designed specifically for operation in  difficult littoral environments while also being usable in deeper water.

This new torpedo is designated the Torped 47, it replaces an earlier type with similar characteristics, the Torped 45. Compared to the US Navy’s Mk54, they are longer (2.85 m (9.35′) vs (2.72m (8.91′), heavier (340 kg (750 lb) vs 276 kg (608 lb)), and of greater diameter (400mm (15.75″) vs 324mm (12.75″)).


Finnish Navy conducted its first torpedo firing from FNS Tornio Hamina-class fast-attack craft in the Archipelago Sea with a TP45 torpedo. (Picture source Finnish Navy)

They use a LiFPO4 battery which is rechargeable, so it is likely practice torpedoes can be used numerous times and quickly returned to service. Believe this is more difficult with the Otto fueled USN torpedoes.


New Multi-Mission Very Light Weight Torpedo

Very Light Weight Torpedo

In 2013, when I first heard that the Navy was developing an Anti-Torpedo Torpedo, I had hopes it might be the basis for a ship stopping system for the Coast Guard. In 2019, we learned that the systems which had been deployed on five of the Navy’s aircraft carriers were being removed. It seemed the program was dead. In fact, it appears very much alive, and apparently the Navy has targets other that adversary torpedoes in mind. If the Coast Guard is ever to have this weapon it may be important to understand what the Navy might see in the system.

Northrop-Grumman press release quoted in part:

Northrop Grumman has successfully manufactured and tested the first industry-built Very Lightweight Torpedo (VLWT) for the U.S. Navy. The prototype torpedo is based on the Pennsylvania State University Applied Research Laboratory’s (PSU-ARL) design that was distributed to defense industrial manufacturers in 2016. Northrop Grumman, which independently funded the research and development, will offer the design-for-affordability improvements to this VLWT as Northrop Grumman’s response for the Navy’s Compact Rapid Attack Weapon program.

Applying its engineering and manufacturing expertise, Northrop Grumman improved upon the VLWT baseline design to replace high-cost components and drive overall affordability, reproducibility and reliability. Those altered sections were built and tested using PSU-ARL’s own test equipment for confidence.

“The successful testing of the torpedo nose on the first try is a testament to Northrop Grumman’s design-for-affordability approach, which will significantly reduce cost without sacrificing operational performance,” said David Portner, lead torpedo program manager, undersea systems, Northrop Grumman.

TheDrive dug into this a bit further and found the supporting FY2021 budget line items  and justification under the name Compact Rapid Attack Weapon (CRAW), significantly it is a program of record.

The thing I find interesting is, this is touted a multi-platform, multi-mission weapon. The primary capability being talked about is as a hard kill anti-torpedo weapon, but apparently it is a modular weapon that may be reconfigured for different missions.

There is more information in an earlier TheDrive article.

These weapons could offer added offensive firepower, as well as an all-new anti-torpedo defense interceptor capability. The mini-torpedoes use a common body and future variants might also arm unmanned ships or submarines, as well as flying drones, act as naval mines, and more.

A Navy briefing slide showing the internal components and describing the various features of the PSU_ARL Common Very Light Weight Torpedo (CVLWT) design

The Common Very Light Weight Torpedo design that the weapon is based upon is reportedly 6.75″ in diameter, about 85″ in length, and weighs about 220 pounds (100 kilos). If it is truly modular its length and weight may vary somewhat. It might be possible to make a version with an enlarged warhead.

The familiar Mk46 light weight torpedo is more than twice as large. The newer Mk 50 and Mk54 torpedoes are similarly sized.

  • Length: 8 ft 6 in (2.59 m), 102 in
  • Weight: 508 lb (230 kg) (warshot configuration)
  • Diameter: 12.75 in (323.8 mm)
  • Range: 12,000 yd (10,973 m)
  • Warhead: 96.8 lb (43.9 kg)

The Navy’s standard heavy weight torpedo, the Mk48, is 16 times larger than the Common Very Light Weight Torpedo design.

  • Length: 19 feet (5.8 meter) or 228 in
  • Weight: 3,695 lb (1,676 kg) (ADCAP)
  • Diameter: 21 in

Advantages of small size: Small size can convey several advantages.

  • More weapons
  • Smaller cross section
  • Lower noise
  • Use by smaller platforms

A smaller weapon allows a greater number of weapons in a given magazine space. Space for torpedoes on submarines is limited and the Mk48 costs $10M each, so there are good reasons not use too many on one target or to use them on small targets . The VLWT could be used to swarm larger targets or individually against small craft including unmanned surface and subsurface vessels. As a rough estimate it looks like about 14 of these smaller weapons could fit in the space currently required for one Mk48 torpedo.

A helicopter could probably carry at least twice as many VLWT compared to the current light weight torpedoes. 

The frontal area of a 6.75″ torpedo is only 10.3% that of a 21″ torpedo meaning that it would be harder to detect using active sonar.

The power required to propel such a small torpedo is significantly less that that of a 21″ torpedo. Consequently it should put much less noise in the water, making it harder to detect by passive means

Being harder to detect means these weapons could probably get closer to a target before it becomes aware it is under attack.

Light weight and small size also means these weapons might be deployed from platforms that currently cannot support heavier weapons. These might include the Common Unmanned Surface Vehicle (CUSV) or the MQ-8C Fire Scout drone helicopter. It might also arm the MQ-4C Triton.

Textron Systems’ CUSV with Surface Warfare payload at SAS 2019

Parallels from above water missiles: What we are seeing here has parallels to what has already happened in the field of guided missiles above water.

  • Smaller but more numerous missiles
  • Simultaneous or closely sequenced attack
  • Multi-Packed missiles
  • Anti-Radiation missiles

The Russian Navy is putting smaller missile on their ships but in greater numbers. We see them moving from four very large missiles to 16 smaller missile. It is perhaps less obvious, in the US Navy, but they are using the smaller Naval Strike Missile in applications where they would previously used the larger Harpoon missile, and it appears the new frigate will be equipped to carry 16 of these. The reasoning is understandable. With increasingly robust anti-missile defenses, there is a need to swam the defenses with numerous missiles arriving simultaneously or in closely sequenced attacks. As torpedo countermeasures become more effective there may be a similar move to launch a swarm of smaller torpedoes.

We have begun to see more than one missile housed in a single VLS. The Evolved Sea Sparrow Missile (ESSM) is commonly packed four to a canister in Mk41 VLS and the larger launch tubes like the Virginia Payload Module may house even more missile in a single tube. Similarly, it appears that it might be possible to use a canister to launch as many as seven of the VLWT from a single torpedo tube without the need to reload.

The concept of the Virginia Payload Module

Since at least the Vietnam war, we have seen anti-radiation missiles used to attack sensors controlling countermeasures systems including missile control radars. We may see the use of VLWT to attack active sonar systems that might cue torpedo countermeasures prior to arrival of a larger torpedo.

Submarine Attack on Surface Ship Scenario:

VLWT might be used as follows to attack a surface combatant.

The enemy vessel is, for the scenario, a Project 22350 Admiral Gorshkov class frigate with both hull mounted and towed active/passive sonars, a towed torpedo decoy system, and a PAKET-NK hard-kill anti-torpedo defense system.

The US submarine launches seven VLWT and a single Mk48 torpedo in a sequenced attack. The VLWT are launched first to arrive earlier than the Mk48. The first VLWT sacrificially destroys the towed decoy. The remaining six target first the active sonar sources and then the ship itself. With six targets inbound, the PAKET-NK hard kill system has only four ready rounds. If it works perfectly, it will destroy four of the six remaining VLWT, but the other two will destroy the two active sonars including the one in the bow. When the Mk48 arrives it will have no distractions to deal with and will detonate under the frigate, breaking its back.

For the Coast Guard:

It appears these Very Light Weight Torpedoes may be adequate for what I see as the Coast Guard’s requirement to be able to forcibly stop any vessel regardless of its size. It would need to be able to target the ships propellers, but this has been possible since WWII. Given their size and weight, and apparently relatively low cost, even WPCs and WPBs should be able to carry more than one or two to provide redundancy.

Coast Guard manned Destroyer Escort USS Menges, victim of a German Navy Acoustic Torpedo, 3 May, 1944

Webber class Could be the Navy’s Light Duty Pickup Truck

Coast Guard Cutter John F. McCormick (WPC 1121) crew transits through the San Francisco Bay, Saturday, March 4, 2017, during their voyage to homeport in Ketchikan, Alaska.  Coast Guard photo by Petty Officer 2nd Class Loumania Stewart

In 2012 the US Naval Institute published an important article by then CNO Admiral Johnathan Greenert, “Payloads over platforms: Charting a new course.” It starts off, 
“We need to move from ‘luxury-car’ platforms—with their built-in capabilities—toward dependable ‘trucks’ that can handle a changing payload selection. “
He suggested that the Navy needs F150 pickups rather than Ferraris. Metaphorically the Webber class could be the Navy’s small Toyota pickup–cheap, reliable, versatile, and economical to operate. 
A strong point for the Webber class is that it is probably the smallest and cheapest combatant, being currently manufactured, that can self deploy anywhere in the world (other than the polar regions) with minimal support en route as demonstrated by their self deployment to Hawaii and Alaska and USCGC Olivier F. Berry (WPC-1124)’s successful patrol to the Marshall Islands, 2200 miles from her homeport in Honolulu.
As currently equipped there is not a lot of free space apparent on the Webber class, but removing the eight meter “over the horizon boat” would free up a large area where mission modules could be placed. We can think of it as the bed of the pickup.

U.S. 5TH FLEET AREA OF OPERATIONS (Feb. 1, 2018) Island-class patrol boats USCGC Wrangell (WPB 1332), left, USCGC Aquidneck (WPB 1309), middle, and coastal patrol ship USS Firebolt (PC 10) patrol the open seas. Wrangell, Aquidneck and Firebolt are forward deployed to the U.S. 5th Fleet area of operations in support of maritime security operations to reassure allies and partners and preserve the freedom of navigation and the free flow of commerce in the region. (U.S. Navy photo by Mass Communication Specialist 2nd Class Kevin J. Steinberg/Released)

Potential Missions
Countering the Swarm: 
The Navy’s most likely first use of a Webber class could be as replacements for the Cyclone class in South West Asia. Countering the large number of Iranian fast inshore attack craft (FIAC) is a mission the Cyclone class is expected to do now, protecting both larger Navy vessels and the tanker traffic that must pass through the Straits of Hormuz. 

The Fletcher laser guided rocket launcher fires BAE’s 2.75 inch laser guided rockets known as the Advanced Precision Kill Weapon System. (Shawn Snow/Defense News Staff)

An earlier post, “Modifying Webber Class Cutters for Duty in SW Asia,” was aimed at this threat as applied to the Coast Guard Webber class that will be going to Southwest Asia. As a minimum the Navy will likely want some form of guided weapon, Perhaps the APKWS would suffice, if provided in sufficient numbers.

Spike LR Missile launched from a Typhoon weapon station on an Israel Navy Super Dvora Mk 2. A similar configuration was recently tested by the US Navy, from an unmanned surface vessel (USV-PEM). Photo: RAFAEL

The 25mm Mk38 Mod2/3 that are currently mounted on the Webber class might be up-gunned (30, 35, and 40mm guns are all possible) and the mount might also be modified to also launch APKWS. Alternately the Mk38 might be replaced by BAE’s 40mm/70 MK4 and the Toplite gun director c(urrently mounted on the Mk38) could be mounted on the mast to control the 40mm, as the Israelis have done with some of their installations of the system, assuming the 40mm Mk 4 does not weigh too much.  

BAE Bofors 40mm/70 mk4

Optimally, the outfit should include Longbow Hellfire. It could probably be mounted as single tube launchers affixed along the sides of the superstructure. I have seen a mockup of such a launcher. The missile itself is only about seven inches in diameter. If willing to replace the boat with missiles, its likely Lockheed could produce a 12 round launcher based on half the launcher being installed on the LCS. 

ATLANTIC OCEAN—A Longbow Hellfire Missile is fired from Littoral Combat Ship USS Detroit (LCS 7) on Feb. 28 2017 as part of a structural test firing of the Surface to Surface Missile Module (SSMM). The test marked the first vertical missile launched from an LCS and the first launch of a missile from the SSMM from an LCS. (Photo by U.S. Navy)

In other theaters there is likely a desire to have a larger anti-ship missile. 
The Navy has been talking a great deal about “Distributed Lethality.” The concept has its origin in a January 2015 US Naval Institute article by then-Director of Surface Warfare Requirements (OPNAV N96) Rear Admiral Tom Rowden, RAdm. Peter Gumataotao, and RAdm. Peter Fanta. 
Rowden’s co-author and successor at N96, Rear Admiral Pete Fanta, continued the drum beat with the memorable phrase, “if it floats, it fights,” suggesting that anti-ship missiles should be put on virtually all units. 
On the Webber class, this would most likely the Naval Strike Missile (NSM), recently chosen by the Navy to arm its LCSs and frigates. A four cell launcher could probably replace the boat. The missile is only 13 feet long. 

A Kongsberg Naval Strike Missile (NSM) is launched from the U.S. Navy littoral combat ship USS Coronado (LCS-4) during missile testing operations off the coast of Southern California (USA). The missile scored a direct hit on a mobile ship target. 23 September 2014.
U.S. Navy photo by Mass Communication Specialist 2nd Class Zachary D. Bell

Missile Truck
The Army and Marines have tracked and truck mounted missile launchers. 
A new missile, “Deepstrike,” is being developed for these launchers. “The missile will be able to strike targets up to 309 miles away with precision, including moving targets both on land at sea.” (see also)
A Webber class equipped with these could function in the same way as the Army and Marine vehicles operating in the littorals and many river systems. Targeting would be provided by offboard sensors through networking. 
Anti-Submarine Warfare (ASW)
This is probably unlikely, but there might be a place for craft that could perform ASW patrols off ports and amphibious objective areas or around choke points. 
The Canadians have a small containerized towed array sensor that looks like it would fit.

TRAPS containerized active/passive towed array from GeoSpectrum Technologies.

 I have looked at how we might add torpedo tubes to the Webber class that could launch ASW torpedoes, but it is more likely aircraft, most likely helicopters, would be called in to make the actual attack. The ship would be primarily a sensor node, minimizing the requirement to keep ASW Helicopters airborne.
120mm Mortar for Naval Surface Fire Support:
Another truck like use would be to add this containerized large mortar as a way to provide naval fire support. This weapon is not currently in the US inventory but it does look promising. Guided projectiles are being developed for the 120 mm mortar.
Security for MSC’s PrePositioned Afloat Fleet

I am not sure what precautions the Navy has made to protect the ships of the MSC’s PrePositioned Afloat Fleet, but if I were an enemy there are might be strong incentive to destroy these ships that transport the most ready reinforcements of heavy equipment.

Webber class PCs might have a role in protecting these.

 Large Unmanned Surface Vessel. 

The Navy is seeking to procure a medium unmanned surface vessel (MUSV), 12 to 50 meters in length. The Webber class might be the basis for such a vessel. The modular systems described above might also be used on the MUSV. 

Visit, Search, Board, and Seizure: 

This is the mission these little ships are built for and, consequently, no change may be necessary. The mission might be stopping and boarding hundreds of small craft as was done off Vietnam as part of Operation Market Time, or it might be enforcing a blockade against Chinese shipping at the Straits providing access to the South China Sea. If resistance is expected there are a number of ways the vessels’ armament could be augmented, including missiles or torpedoes, but in most cases its likely air or backup could be called in. The real advantage is that the Navy would not need to tie down DDGs doing this work, and potentially risk it being damaged by improvised weapons on a vessel being boarded. For more challenging assignments two or three could be teamed with one or two providing boats and boarding teams and the other as a weapons carrier.

USRC/USCGC McCulloch Wreck located

n 1914, USRC Cutter McCulloch was ordered to Mare Island Navy Shipyard where the cutter’s boilers were replaced, the mainmast was removed and the bowsprit shortened. In 1915, McCulloch became a US Coast Guard Cutter when the US Revenue Cutter Service and US Life-Saving Service were combined to create the United States Coast Guard. (Credit: Gary Fabian Collection)

You may have heard the wreck of the Cutter McCulloch, a participant in the Battle of Manila Bay, has been found of Pt. Conception.

The best coverage I have found is on the NOAA website.

There does seem to be an error in that it refers to the guns on the McCulloch as four 6-pounder, 3-inch rapid firing guns. 6-pounders were 57mm weapons (sound familiar?) while 3-inch guns typically fired a projectile of 13 pounds. Those figures are very close to projectile weights of the modern 76mm Mk75 and 57mm Mk110. The confusion may have originated from the fact that while the McCulloch, as built, was armed with 6-pounders, before the Battle of Manila Bay, she was up-gunned.

There is an interesting footnote on the McCulloch’s Spanish American War service.

Dewey presented USRC McCulloch with four of the six 1-pounder revolving Hotchkiss guns taken from the Spanish flagship, Reina Cristina. Each of these Hotchkiss cannons had five, revolving 37mm barrels. These four guns are displayed in pairs to either side of the front of Hamilton Hall facing the parade ground at the United States Coast Guard Academy.

As an advocate of torpedoes on cutters, I liked seeing the McCulloch had a torpedo tube, see, there is precedence.


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.


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)

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.



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.


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.


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


Coast Guard and CG Manned Vessels Lost in World War II


Coast Guard manned destroyer escort USS Menges (DE-320) showing the effects of an acoustic homing torpedo hit on the stern.

It is entirely appropriate for Veteran’s Day weekend reading, but this post was prompted by a recent update of the list of “Top Ten Posts.” I found that the 2011 post “What Does It Take to Sink a Ship?” was not only the top post since I started writing, it is also the top post of 2016. That looked at Navy major surface combatant losses in WWII, but I realized I have never surveyed the Coast Guard’s WWII losses.

This began as another shameless attempt to get the Coast Guard to recognize that they need torpedoes to stop medium to large ships, but it grew into a more comprehensive look at CG losses in WII. I did find that six (or seven, Escanaba?) Coast Guard or CG manned vessels were hit by torpedoes and in every case the ship was either sunk (four or five?) or immobilized (two).

I found a couple of good sources. “The Coast Guard at War” is a series of monographs completed shortly after WWII (between 1045 and 1950) and most of the apparently 25 volumes are available in pdf format here, along with a lot of other WWII references. In particular I used The Coast Guard At War: Lost Cutters (Official History Series, Volume VIII, 1947). It lists the loss of 16 Coast Guard vessels and the loss of 12 Coast Guard manned Navy vessels, but two of these (one Navy and one CG) were actually after the war was over. My other source was “U. S. Coast Guard Ship Losses” by Jim Gill, on the US Coast Guard Light Ship Sailors Association International web site. This source identifies 40 losses beginning with the Tahoma in 1914 up to USCGC Mesquite (WLB-305), grounded in 1989. It included three losses not listed in the official history, all by torpedoes:

  • (FS-255), a small Army freighter, 560 tons, torpedoed and sunk by a Japanese submarine while anchored, 11 May 1945, with the loss of four men.
  • USS Menges (DE-320), 1,590 tons, torpedoed while on convoy duty, 4 May, 1944, the ship survived severe damage to her stern, but there were 31 dead.
  • USS Etamin (AK-93), 7,176 tons, which was hit by a hit by an air launched torpedo and damaged badly enough that it was decommissioned and was used subsequently as an unpowered floating warehouse. One dead.

Coast Guard Vessels Lost:

The Coast Guard lost 15 vessels during the course of WWII. Of those, three are believed to be the result of enemy action. Of the remaining 12, eight were a result of adverse weather. 214 Coast Guardsmen were killed in these 15 incidents.

The three ships presumed loss to enemy action included the three largest Coast Guard vessels lost during the war:

CG 85006, 67 tons, was destroyed by an explosion, probably gasoline vapors, 27 Mar.’43, four dead.

CG 58012, 30 tons, was destroyed by fire, 2 May ’43, no fatalities.

CG 83421, 44 tons, was sunk in a collision, 30 June ’43, no fatalities.

USCGC Bodega (WYP-342), 588 tons, went aground attempting to assist another vessel, 20 Dec. ’43, no fatalities.

The eight vessels lost to foul weather were:


LV 73 on the Vineyard Sound station where she served from 1924 through 1944.  On 14 September 1944 she was carried off station during a hurricane and sank with the loss of all hands.

It might be assumed that the non-combat casualties were not war related, but that might not be the case. The urgency of the missions, the diversion of more capable ships to escort duty, the influx of inexperienced personnel placed in responsible positions, and the use of vessels pressed into service for which they may have been ill-suited, were all a result of the war, and it led to crews being placed in more danger than would have been the case in peacetime.

Coast Guard Manned Navy Vessels Lost:

Of the eleven Coast Guard manned US Navy ships lost during WWII, seven were lost to enemy action, the others were:

  • LST 203, 2,366 tons, was stranded after an intentional beaching, 1 Oct. ’43, no fatalities.
  • LST-69, 2,366 tons, destroyed in the West Loch disaster, 21 May ’44, no fatalities.
  • USS Serpens (AK-97), 14,250 tons, destroyed as a result of an apparent internal explosion of its cargo, 29 Jan. ’45, 196 CG fatalities. (Largest single loss of CG personnel)
  • USS Sheepscot (AOG-24), 2,270 tons, driven ashore by adverse weather, 6 June ’45, no fatalities.


USS Serpens (AK-97)  US Navy photo #NH 89186, from the collections of the US Naval Historical Center, courtesy William H Davis, 1997


USS Sheepscot (AOG-24) underway, August 1944, US Navy photo

Those lost to enemy action were:


Photo: USCGC Muskeget, seen here before conversion to a weather ship.


“LST discharges supplies. . .”; no date (November, 1943?); Photo No. 3237; photographer unknown. The Coast Guard-manned LST-69 disembarks equipment during the Tarawa invasion.


USS Leopold (DE-319) being launched. 


Normandy Invasion, June 1944 A convoy of Landing Craft Infantry (Large) sails across the English Channel toward the Normandy Invasion beaches on “D-Day”, 6 June 1944. Each of these landing craft is towing a barrage balloon for protection against low-flying German aircraft. Photograph from the U.S. Coast Guard Collection in the U.S. National Archives. Photo #: 26-G-2333


“SHE FELT THE NAZIS’ WRATH:” A U.S. Coast Guard infantry landing craft still flies its flag, though knocked out of the invasion, ripped and wounded on the beaches of France. Moving in for a landing, the LCI ran afoul of an underwater obstruction, which tore a gaping hole in her bow. Then as its cargo of troops piled ashore, Nazi shells battered her out of further action.”; no date; Photo No. 2395; photographer unknown.


It may be surprising that it appears the Coast Guard lost two and half to three times as many men in Coast Guard manned Navy vessels, as in Coast Guard vessels.

According to the Coast Guard history web site,

Two hundred and fourteen thousand two hundred and thirty-nine persons served in the Coast Guard during World War II.  That number included 12,846 women.  The Coast Guard lost a total of 1,917 persons during the war with 574 losing their life in action, “died of wounds” received in action, or perishing as a “Prisoner of War.”

These incidents account over 40% of all lives lost and a majority of lives lost as a result of enemy action.

How About a Coast Guard Sink-Ex?

Test firing of the 57mm Bofors aboard USCGC Bertholf, photo by MMagaro

Test firing of the 57mm Bofors aboard USCGC Bertholf, photo by MMagaro

Are our weapons adequate for the Ports, Waterways, and Coastal Security Mission? Let’s find out.

The Navy Times is reporting that the Navy will have an unusually large number of ships available for “Sink-Ex” exercises in 2017.

The SINKEX fleet grew from five ships last year to seven ships available in 2017, including four frigates, the landing ship tank Racine and two attack cargo ships.

According to the source document, the Navy’s 30 year shipbuilding plan (pp 13/14), one of the stated purposes of a Sink-EX is weapons effectiveness evaluation. I think this might be a good opportunity for us to test out our weapons for the Ports, Waterways, and Coastal Security (PWCS) mission. This mission implies we must have the ability to forcibly stop a ship, regardless of its size. A Sink-Ex could be an opportunity to answer once and for all the question “Is the Coast Guard adequately armed for the mission?”  Personally I don’t think so, and what little evidence we have seems to indicate that is the case.

The two attack cargo ships are Charleston class LKAs, the ex-Durham (LKA-114) and ex-St. Louis (LKA-116), built in the late ’60s. These are medium sized auxiliary ships, 9,000 tons light and 18,500 tons fully loaded, 576 feet (176 meters) in length. Structurally they are not much different from merchant ships of the period. Unfortunately they don’t have the big diesel engines found on modern merchant ships, and the are far smaller than many current merchant ships but they are still, in most respects, representative of the target set the Coast Guard should be interested in.


Photo: USS Charleston (LKA-113)

We have four gun systems that might be tested. .50 cal., 25 mm, 57 mm, and 76 mm. The 25 mm and 57 mm are particularly important as the .50 cal is probably too small and short ranged and the 76 mm is going out of service. Still, we should still attempt to include the 76 mm because if the 57 mm proves inadequate, our next question should be, “Would the 76 mm have been successful?” Testing the 25, 57, and 76 mm guns would require use of at least two ships, a 378 for both the 76 and 25 mm, and a Bertholf class for the 57 mm. (Alternately an LCS might provide the 57 mm, a Bear class the 76 mm, and a 110 or Webber class the 25 mm.)


This could be a CG R&D project, but of course it would require Navy assistance, perhaps a joint project. Because our objective is to at least stop the target, rather than sink it, loss of power or steering would constitute a success. To determine if this is the case, we need information about what is happening inside the hull when the we get a hit. Will the round penetrate not only the hull but also critical systems, the loss of which would result in loss of power or control of the ship? Because it would probably be dangerous to go back on board the target after it has been shelled, the target would need to be instrumented with sensors and the results broadcast back. Aside from putting cameras inside the spaces, a technique might be to seal up and pressurize equipment like boilers, turbines, and steering gear and have them instrumented to detect any loss of pressure that would indicate a breach.

We would also want to conduct the exercise at a reasonable ranges. Since the real targets might be equipped with weapons that might be typically available to terrorist organizations, including anti-tank missiles and Soviet era antitank and anti-aircraft guns,that might target critical systems on the cutter, I believe the cutter should stand off at least 4000 yards, but for the 25 mm, we would probably need to close to 3,000 yards. A logical sequence might be,

  1. 378 closes to 3000 yards engages with 25 mm then withdraws
  2. NSC closes to 4,000 yards and engages, then withdraws
  3. 378 closes to 4,000 yards and engages.

We would also want to fire a reasonable number of rounds, probably about 150 rounds of 25 mm, about 100 rounds of 57 mm, and about 80 rounds of 76 mm, basically shoot enough to exhaust the ammunition normally carried on the mount.

Realistically this would have to be part of a larger Sink-Ex with more than one target, but it might be reasonable to allow the Coast Guard a day to try their systems against one of the targets before the other firing units come on scene.

Should our current systems prove not up to the task, we would also want to know the results for possible candidate systems, so we might ask that these candidate systems be used against the target as well. These might include, APKWS, Griffin, Hellfire, the 5″ gun, and the light weight torpedo. I don’t think it has ever been tried, but with the right depth settings, is it possible to hit a deep draft surface target with our current light weight torpedoes?

Let’s at least find out if we have a chance of succeeding in this mission. 

ACERM–Another Light, Precise, Weapon to Hit Small Moving Targets


81mm mortar used by the Coast Guard during the Vietnam era

It seems technology is making hitting small, fast, maneuverable targets with precision not only easier, but also cheaper.

We have talked before about the possibility of using small guided missiles (Hellfire, Brimstone, Griffin, or 70 mm guided rockets like APKWS) to allow the Coast Guard to engage small, fast, highly maneuverable threats, while minimizing the chances of collateral damage that accompany the use of unguided rounds from machineguns or auto cannon. Now there seems to be another alternative, and it even has a history of use by the Coast Guard, the 81 mm mortar.

Popular Mechanics reports the Marines will be getting a guided 81 mm round called ACERM (Advanced Capability Extended Range Mortar) that will incorporate both a GPS, and potentially more importantly for the Coast Guard, a semi-active laser (SAL) guidance system that should provide a one meter circular error probability (CEP, that is 50% of the rounds will fall within one meter of where the laser is pointed). Additionally the round will have a range of about 18 kM, comparable to that of a 76 or 57 mm gun. Cost per round is expected to be about $10,000. That is more than the China Lake Spike, but range is much greater and the warhead is substantially larger.

The firecontrol computer/programmer is a two pound “Miniature Mission Setter,” in reality a rugged Android tablet.


In addition to the Popular Mechanics post, I also found this power point presentation (pdf) that provides more detail.

The 81 mm mortars the Coast Guard used in the Vietnam era are all gone now, but they were hardly high tech, expensive, or difficult to produce.

Maybe we at least need the laser designator anyway:

Like some of the other systems considered, in addition to the mortar and mortar rounds, to use these effectively, we would need a laser designator. Based on a recent contract award, laser designators cost about $60,000 each.

Laser designators might be a good idea anyway. If we need to call in assistance from the Navy, Marine Corp, or particularly the Air Force or Army (who tend to be clueless about marine targets), one of the issues will be identifying the target, and a laser designator would be a good way to do that. Not only to identify the target, but also to show where we want them hit.


While the potential range of the 81mm mortar round may be over 18,000 yards, for our purposes, its effective range is probably limited by the range of the laser designator which can be further limited by atmospheric conditions like fog, rain, snow, smoke or sand storms (like might be encountered in the Persian Gulf). The Power Point brief does suggest that a small unmanned air system (sUAS) equipped with a designator, might be used to complement (and extend) the system.

Because this is a high angle weapon, with the projectile designed to strike the target in a vertical dive, and because the warhead uses “High Density Pre-Formed Fragments” that would presumably spread out horizontally, it probably would not be particularly effective against medium to large ships. It seems to be intended primarily as an antipersonnel weapon. The danger radius for fragments might even be an issue in some circumstances.

It is still a crew served weapon with the crew highly visible and exposed.


Unlike some missile in a box systems, this looks like a gun. It might have some deterrent value in some circumstances.

Reportedly it makes the 50 cal. mounted piggy back more accurate.

If we were in a situation like Market Time, where patrol boats might incidentally support troops ashore, this might be a good option.

Is it the “best” alternative?:

We have an array of possible systems to address the possibility of a maritime terrorist threats. Hellfire, Brimstone, Griffin, APKWS, the China Lake Spike, this smart 81 mm mortar round. All would probably be effective against smaller targets. None are likely to be fully effective against larger targets.

For the larger threats, I have been suggesting WPCs, and probably WPBs, be equipped with light weight torpedoes or even a variant of the anti-torpedo torpedo, to use as a ship stopper that could home on the target’s propellers,

LRASM might also be an alternative. Coordinating a long range LRASM strike is more complex and probably more expensive than the torpedo alternative. On the other hand, it would bring along with it a new naval wartime capability that would support the Navy’s “Distributed Lethality Initiative.”

We really need a set of capabilities that provide a high probability against any element of a spectrum of threats, because if any one element is not addressed, that is likely the element terrorists will select.