Novel Gun Mount

 

NavalToday has a short piece on the new German F-125 frigate. It is primarily to show the video above, of the frigate firing its 27mm guns and 5″/64 Otobreda.

The unusual aspect of the video is the way the mounts for the 27mm guns lean out (see 1:25). I’m not sure it is worth the complication, but it does permit the gun to fire at targets close alongside near the waterline. It probably means it can be fired on bearings closer to the bow and stern too.

Thanks to Mike R. for bringing this to my attention. 

New 40 mm Gun

Thales RAPIDSeaGuardian CIWS Euronaval 2016 newsThales RAPIDSeaGuardian Naval Gun System

Navy recognition is reporting the announcement of a new 40mm naval gun system, based on an existing land based system (pdf). It is claimed to be “a new generation CIWS effective against super sonic seaskimming missile thanks to the airburst ammunition, as well as against asymmetric threats…” while having about the same “footprint and weight as a 25mm system.”

The system is interesting, but the star of the show is the gun and its innovative ammunition. The ammunition is “Case Telescoped” meaning that the shell is embedded in the casing and surrounded by the propellent. The gun and its ammunition are products of CTA International, an equal-shares joint venture company between defence companies Nexter (France) and BAE Systems. The resulting round is very short and shaped like a cylinder rather than the typical double tapered shape of most fixed (one piece) ammunition.

cta-40mm-ammo

The short length of the ammunition means that the portion of the gun inside the mount can be very compact. In the illustration below, the 25mm M242 Bushmaster used in the Mk38 mount is at top right and the Case Telescoped (CT) 40mm is at the bottom right. It’s very compact breech mechanism is apparent.

40mm-ctas-gun

Image source: thinkdefence.co.uk

If this gun could replace our 25mm guns on the Webber class WPCs and the Offshore Patrol Cutters, either by replacing the mount or perhaps by replacing the gun in the Mk38 mod2/3 mounts (also a BAE product), it would give us improvements in range, accuracy, impact, and particularly penetration. Rates of fire for the two systems are the same.

Range: 

The effective range of the Mk38 has been variously reported as 2500 or 3000 yards. This has been a matter of concern to me because when approaching a suspicious vessel that might be being used to make a terrorist attack, I believe a cutter should remain at a distance such that improvised armaments cannot target specific critical equipment on the cutter (like its one gun mount). Improvised armaments might include heavy machine guns, anti-tank guided missiles, or Soviet era anti-aircraft or anti-tank guns of up to 130mm. From my observations and research, in order to preclude targeting critical systems, the cutter should initially approach no closer than 4,000 yards while its boarding party investigates. .

The NavyRecognition post reports a claim of 4,000 meters (4,373 yards) for CTA’s 40mm. While I have not been able to find a claimed max range for the CTA 40mm, the maximum range for the ballistically similar Bofors 40mm/70 is 13,675 yards (12,500 m). The M242 25mm used in the current Mk38 mod2 has a max range of 7,450 yards (6,800 m). Assuming the effective range is proportional to the maximum range, the CTA 40mm should be able to effectively engage from beyond 4000 yards (3,659m).

Penetration: 

The image below, from thinkdefence, shows a comparison of effectiveness against armor using armor piercing fin stabilized fin stabilized discarding sabot (APFSDS) rounds. 

40mm-ctas-armour-piercing-fin-stabilised-discarding-sabot-tracer-apfsds-t

To me, greater armor penetration translates into being able to penetrate the hull and go on to wreck a larger diesel engine than the smaller round.

As far as I can tell, while there is an armor piercing fin stabilized discarding sabot (APFSDS) round for the 25mm, the Mk110 57mm has no round comparable to the APFSDS round offered for the CT 40mm, which has a muzzle velocity of 1,640 meters/second or approximately 5,379 feet/second. The 57mm round would explode shortly after penetrating the skin of the ship, likely before it reached the engine.

Impact: 

Because the 40mm round is about twice as big as the 25mm round, its effective radius is considerably larger.

The image below (also from Thinkdefence) shows a fragmentation comparison between a 30mm airburst round (left) and the 40mm GPR-AB (40mm airburst). The lethal area for the airburst nature at 1,500m is 125m2. Apparently there is no airburst projectile for the 25mm because it is considered to small to be effective. 

40mm-ctas-general-purpose-round-airburst-tracer

Is this gun really ready for “primetime?”

Our friend at thinkdefence.co.uk has done an extensive examination of the development of this weapon.

The gun has been adopted by the British Army for installation on two types of armored vehicles and the French are also planning on using it in one of their armored vehicles.

Apparently the gun is a success and will probably find additional application, including, hopefully, a version of the Mk38.

 

 

“AUGMENT NAVAL FORCE STRUCTURE BY UPGUNNING THE COAST GUARD”–CIMSEC

USCGC_Mellon_(WHEC-717)_launching_Harpoon_missile_in_1990

This is a post I wrote for CIMSEC for their “Distributed Lethality Week,” but their editor thought it would fit better in their “Naval Force Structure Week.” Had I known the topic, I might have spent more time on ASW. 

The Navy has been talking a lot about distributed lethality lately, and “if it floats, it fights.” There is even talk of mounting cruise missiles on Military Sealift Command (MSC) ships, even though it might compromise their primary mission. But so far there has been little or no discussion of extending this initiative to include the Coast Guard. The Navy should consider investing high-end warfighting capability in the Coast Guard to augment existing force structure and provide a force multiplier in times of conflict. A more capable Coast Guard will also be better able to defend the nation from asymmetrical threats.

Why Include the Coast Guard?

A future conflict may not be limited to a single adversary. We may be fighting another world war, against a coalition, perhaps both China and Russia, with possible side shows in Africa, the Near East, South Asia, and/or Latin America. If so, we are going to need numbers. The Navy has quality, but it does not have numbers. Count all the Navy CGs, DDGs, LCSs, PCs and PBs and other patrol boats and it totals a little over a hundred. The Coast Guard currently has over 40 patrol ships over 1,000 tons and over 110 patrol craft. The current modernization program of record will provide at least 33 large cutters, and 58 patrol craft of 353 tons, in addition to 73 patrol boats of 91 tons currently in the fleet, a total of 164 units. Very few of our allies have a fleet of similar size.

point-league-market-time
Coast Guard 82 foot patrol boats interdicted coastal traffic off South Vietnam. (USCG Photo)

Coast Guard vessels routinely operate with U.S. Navy vessels. The ships have common equipment and their crews share common training. The U.S. Navy has no closer ally. Because of their extremely long range, cutters can operate for extended periods in remote theaters where there are few or even no underway replenishment assets. The Coast Guard also operates in places the USN does not. For example, how often do Navy surface ships go into the Arctic? The Coast Guard operates there routinely. Virtually all the U.S. vessels operating with the Fourth Fleet are Coast Guard. There are also no U.S. Navy surface warships home based north of the Chesapeake Bay in the Atlantic, none between San Diego and Puget Sound in the Pacific, and none in the Gulf of Mexico with the exception of mine warfare ships.

In the initial phase of a conflict, there will be need to round-up all the adversaries’ merchant ships and keep them from doing mischief. Otherwise they might lay mines, scout for or resupply submarines, put agents ashore, or even launch cruise missiles from containers. This is not the kind of work we want DDGs doing. It is exactly the type of work appropriate for Coast Guard cutters. Coast Guard ships enjoy a relatively low profile. Unlike a Carrier Strike Group or Navy SAG, they are less likely to be tracked by an adversary.

If we fight China in ten to twenty years, the conflict will likely open with China enjoying  local superiority in the Western Pacific and perhaps in the Pacific in general. If we fight both China and Russia it may be too close to call.

Platforms

The National Security Cutter (NSC)

This class of at least nine and possibly ten, 418 foot long, CODAG powered, 28 knot ships, at 4,500 tons full load, are slightly larger than Perry-class frigates. Additionally they have a 12,000 nautical mile cruising range. As built they are already equipped with:

  • Navy certified helicopter facilities and hangar space to support two H-60 helicopters,
  • A 57 mm Mk110 gun,
  • SPQ-9B Fire Control Radar
  • Phalanx 20mm Close in Weapon System (CIWS)
  • SRBOC/ 2 x NULKA countermeasures chaff/rapid decoy launcher,
  • AN/SLQ-32 Electronic Warfare System,
  • EADS 3D TRS-16 AN/SPS-75 Air Search Radar,
  • A combat system that uses Aegis Baseline 9 software,
  • A Sensitive Compartmented Intelligence Facility (SCIF)

In short, they are already equipped with virtually everything needed for a missile armed combatant except the specific missile related equipment. They are in many respects superior to the Littoral Combat Ships. Adding Cooperative Engagement Capability might even allow a Mk41 equipped cutter to effectively launch Standard missiles targeted by a third party.

USCG National Security Cutter BERTHOLF (USCG Photo)
USCG National Security Cutter BERTHOLF (USCG Photo)

The ships were designed to accept 12 Mk56 VLS which launch only the Evolved Sea Sparrow missiles (ESSM). Additionally, the builder, Huntington Ingalls, has shown versions of the class equipped with eight Mk41 VLS (located between the gun and superstructure) plus eight Harpoon, and Mk32 torpedo tubes (located on the stern). Adding missiles to the existing hulls should not be too difficult.

LRASM_TSL_Concept_Lockheed_Martin
LRASM topside launcher concept. The size and weight are comparable to launchers for Harpoon. (Lockheed Martin photo)

The Mk41 VLS are more flexible in that they can accommodate cruise missiles, rocket boosted antisubmarine torpedoes (ASROC), Standard missiles, or Evolved Sea Sparrow missiles (ESSM). Using the Mk41 VLS would allow a mix of cruise missiles and ESSM with four ESSMs replacing each cruise missile, for example eight cells could contain four cruise missiles and 16 ESSM, since ESSM can be “quad packed” by placing four missiles in each cell. Development of an active homing ESSM is expected to obviate the need for illuminating radars that are required for the semi-active homing missiles. Still, simpler deck mounted launchers might actually offer some advantages, in addition to their lower installation cost, at least in peacetime.

Cutters often visit ports where the population is sensitive to a history of U.S. interference in their internal affairs. In some cases, Coast Guard cutters are welcome, while U.S. Navy ships are not. For this reason, we might want to make it easy for even a casual observer to know that the cutter is not armed with powerful offensive weapons. Deck mounted launchers can provide this assurance, in that it is immediately obvious if missile canisters are, or are not, mounted. The pictures below show potential VLS to be considered.

The relatively small footprint of the Mk56 VLS system (pdf) can be seen here on a Danish Absalon-class command and support ship (beam 64 feet, by comparison the National Security Cutters’ beam is 54 feet). Two sets are visible in the foreground, one set of twelve with missile canisters with red tops in place to the right, on the ship’s centerline, and a second set of twelve without canisters to the left. The Absalon-class has three twelve-missile sets, with the third set off camera to the right. (Royal Danish Navy)
VLSLauncher_korvet
12 earlier Mk48 mod3 VLS for ESSM seen here mounted on the stern of a 450 ton 177 foot Danish StanFlex300 Flyvefisken-class patrol boat. The Mk56 launchers replace the Mk48s with an approximate 20% weight savings.
The Offshore Patrol Cutter (OPC)

The OPC  program of record for provides 25 of these ships. A contract has been awarded to Eastern Shipbuilding Group for detail design and construction of the first ship, with options for eight more. The notional design is 360 feet long, with a beam of 54 feet and a draft of 17 feet. The OPCs will have a sustained speed of 22.5 knots, a range of 10,200 nautical miles (at 14 knots), and an endurance of 60-days. It’s hangar will accommodate one MH-60 or an MH-65 and an Unmanned Air System (UAS).

opcplacemat

Notional design characteristics and performance of the OPC. (USCG Image)

It will have a space for a SCIF but it is not expected to be initially installed. As built, it will have a Mk38 stabilized 25 mm gun in lieu of the Phalanx carried by the NSC. Otherwise, the Offshore Patrol Cutter will be equipped similarly to the National Security Cutter. It will likely have the same Lockheed Martin COMBATSS-21 combat management system as the LCS derived frigates. It is likely they could be fitted with cruise missiles and possibly Mk56 VLS for ESSM as well. Additionally these ships will be ice strengthened, allowing the possibility of taking surface launched cruise missiles into the Arctic

The Fast Response Cutter (FRC)

The FRC program of record is to build 58 of these 158 foot, 28 knot, 365 ton vessels. 19 have been delivered and they are being built at a rate of four to six per year. All 58 are now either built, building, contracted, or optioned. They are essentially the same displacement as the Cyclone class PCs albeit a little slower, but with better seakeeping and a longer range. Even these small ships have a range of 2,950 nm. They are armed with Mk 38 mod2 25 mm guns and four .50 caliber M2 machine guns.

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The first Sentinel-class Fast Response Cutter (FRC), USCGC Bernard C. Webber. (USCG photo)

They are already better equipped than the Coast Guard 82 foot patrol boats that were used for interdiction of covert coastal traffic during the Vietnam war. If they were to be used to enforce a blockade against larger vessels, they would need weapons that could forcibly stop medium to large vessels.

The Marine Protector Class

There are 73 of these 87 foot, 91 ton, 26 knot patrol boats. Four were funded by the Navy and provide force protectionservices for Submarines transiting on the surface in and out of King Bay, GA and Bangor, WA.

File:US Navy 090818-N-1325N-003 U. S. Coast Guardsmen man the rails as the U.S. Coast Guard Cutter Sea Fox (WPB 87374) is brought to life at Naval Base Kitsap.jpg
Photo: KEYPORT, Wash. (Aug. 18, 2009) U. S. Coast Guardsmen man the rails as the U.S. Coast Guard Cutter Sea Fox (WPB 87374), one of four of this class assigned to Force Protection units. (U.S. Navy photo Ray Narimatsu/Released)

If use of these vessels for force protection were to be expanded to a more hostile environment, they would likely need more than the two .50 caliber M2 machine guns currently carried.  The four currently assigned to force protection units are currently equipped with an additional stabilized remote weapon station.

Weapons

Cruise Missiles

The U.S. Navy currently has or is considering four different surface launched cruise missiles: Harpoon, Naval Strike Missile (NSM), Long Range Anti-Ship Missile (LRASM), and Tomahawk. Of these, LRASM appears most promising for Coast Guard use. Tomahawk is the largest of the four and both Harpoon and NSM would be workable, but they do not have the range of LRASM. The intelligence and range claimed for the LRASM not only makes it deadlier in wartime, it also means only a couple of these missiles on each of the Coast Guard’s largest cutters would allow  the Coast Guard’s small, but widely distributed force to rapidly and effectively respond to asymmetric threats over virtually the entire U.S. coast as well as compliment the U.S. Navy’s efforts to complicate the calculus of a near-peer adversary abroad

Small Precision Guided Weapons

It is not unlikely that Fast Response Cutters will replace the six 110 foot patrol boats currently based in Bahrain. If cutters are to be placed in an area where they face a swarming threat they will need the same types of weapons carried or planned for Navy combatants to address this threat. These might include the Sea Griffin used on Navy’s Cyclone-class PCs or Longbow Hellfires planned for the LCS.

Additionally, a small number of these missiles on Coast Guard patrol craft would enhance their ability to deal with small, fast, highly maneuverable threats along the U.S. coast and elsewhere

Light Weight Anti-Surface Torpedoes 

If Coast Guard units, particularly smaller ones, were required to forcibly stop potentially hostile merchant ships for the purposes of a blockade, quarantine, embargo, etc. they would need something more that the guns currently installed.

The U.S. does not currently have a light weight anti-surface torpedo capable of targeting a ship’s propellers, but with Elon Musk building a battery factory that will double the worlds current capacity and cars that out accelerate Farraris, building a modern electric small anti-surface torpedo should be easy and relatively inexpensive.

Assuming they have the same attributes of ASW torpedoes, at about 500 pounds these weapons take up relatively little space. Such a torpedo would also allow small Coast Guard units to remain relevant against a variety of threats.

Conclusion

Adding cruise missile to the Coast Guard National Security Cutters and Offshore Patrol Cutters would increase the number of cruise missile-equipped U.S .surface ships by about 40 percent.

Coast Guard Patrol craft (WPCs) and patrol boats (WPBs) significantly outnumber their Navy counterparts. They could significantly increase the capability to deal with interdiction of covert coastal traffic, act as a force multiplier in conventional conflict, and allow larger USN ships to focus on high-end threats provided they are properly equipped to deal with the threats. More effective, longer ranged, and particularly more precise weapons could also improve the Coast Guard’s ability to do it Homeland security mission.

Thanks to OS2 Michael A. Milburn for starting the  conversation that lead to this article.

UAE Transport, Former US High Speed Vessel Swift, Hit by Shore based ASCM

There have been numerous reports (and here) that the former US Navy High Speed Vessel Swift has been attacked and apparently destroyed by a Chinese designed but possibly Iranian built C-802 anti-ship cruise missile (ASCM) while transiting the 25 mile wide Bab-el-Mandeb Strait at the southern end of the Red Sea.

Map of Bab-el-Mandeb.png

Map of the Bab-el-Mandeb by Archer90

The missile was launched by a rebel group in Yemen. This not the first report of their use of anti-ship cruise missiles. They have claimed to have hit ships of the Saudi led coalition before. Plus the American built Israeli Corvette Hanit was hit by a Hezbollah launched C-802 in 2006. If we ever get in a situation like MarketTime again, there is a good possibility that even insurgent groups might have ASCMs.

The C-802 is similar in size and capabilities to the US build Harpoon. There is at least one report that the former Swift deployed Mk36 SRBOC.

Thanks to Peter for bringing this to my attention. 

Addendum: 

A photo of the vessel, severely damaged but still afloat here: http://www.marinelog.com/index.php?option=com_k2&view=item&id=23324:video-hsv-swift-hit-by-missile-attack&Itemid=231

They are also saying the damage was done by multiple shoulder launched missile (presumably anti-tank guided missiles) rather than a single ASCM.

Guided 57mm Round Being Developed

NSCfires57mm

Navy Recognition reports that BAE is developing a laser or image recognition guided round for the Mk110 57mm gun that equips the Bertholf Class, National Security Cutter (NSC) and is expected to equip the Offshore Patrol Cutter in addition to the two classes of Littoral Combat Ships.

It is referred to as “Ordnance for Rapid Kill of Attack Craft or ORKA (technical designation: MK295 MOD 1).” Which seems to indicate it is not an anti-aircraft round.

Guided rounds are already available for larger caliber weapons. Guess we will have to wait a while to see if it is actually any cheaper than a guide missile like Griffin or Hellfire. We already know the launcher is not cheaper.

Trade-offs in the 378 FRAM

File:USCGC Sherman WHEC-720 Vietnam War.jpg

Coast Guard photograph, PHC Ken Mather, USCGC Sherman (WHEC-720) in her original configuration with a 5″/38 and dual hedgehogs, April 1969. 

This is hardly a current topic, but it is one I have seen discussed several time, most recently in comments on a post about the new Canadian Arctic/Offshore Patrol Ship (AOPS), e.g. why the Coast Guard used the 76mm Mk75 gun on the 378 FRAMs rather than the 5″/54 Mk45.

It is true that, although about four tons heavier, the early model 5″/54 Mk45 mounts were a drop in replacement for the 5″/38 mounts we had on the 378s. It would have appeared an easy choice, but in order to accommodate the additional weight of the Harpoons and CIWS, perhaps the Coast Guard had no choice but to go with a lighter gun. That gun (and its associated firecontrol system) was certainly seen as a significant improvement over what we had had in essentially all respects including reduced manning and maintenance.

If we look at the weights as built that were removed:

one 5″/38 (20.5 tons) and two hedgehogs (14.4 tons), totalling approximately 35 tons

and compare that to some of the weights added

one 76 mm Mk75 gun (8.2 tons), two Mk141 quad harpoon launchers (11.8 tons total), eight Harpoon (6 tons), and a Mk 15 Phalanx CIWS (6.8 tons).  Total approximately 32.8 tons. Plus more weight for the addition of the hangar. Essentially the difference was a wash.

If instead, we had used the 5″/54 Mk45 mod 0 (24.5 tons) in addition to the harpoons and CIWS, the total weight would have been 16.3 tons higher or 49.1 tons.

There are other weights that might be added in calculating the total weight devoted to armaments, but obviously I don’t think this was an excessive amount, there are too many examples of smaller ships with far more weapons. I previously noted, (“OPC-Design for Wartime, Build for Peacetime”) that as built the little 255s had 140 to 150 tons of weapons.

Even so, an additional 16.3 tons topside (even if that is only about 0.5% of the full load displacement) might have been too much for the 378s. I don’t know. Perhaps a former 378 engineer or DCA could enlighten the discussion.

File:USCGC Mellon WHEC-717.jpgPhoto: Navy photo, USCGC Mellon, with 76mm, Harpoon, and Phalanx CIWS

Another Weapon Option, Brimstone/Sea Spear

Thinkdefense recently reported on the test of a new application of the proven Brimstone missile. (They also have some additional video, and excellent commentary.) Three missiles were launched almost simultaneously against five boats (four stopped and one underway at about 20 knots) simulating a swarm attack. The three missiles each hit a separate target.

Targeting:

The thing that makes this missile so interesting is the range of options it provides the user to ensure that the right target is hit and there is little or no chance of collateral damage. It is equipped with an all weather millimetric radar that will show the shape of the target, and in the latest version semi-laser homing. It can be “fire and forget,” but it can also allow a “man-in-the-loop.” It can be given a laser designation and then continue to independently track the target. It has a terrain avoidance feature allowing it to hit targets on the far side of islands. A kill box can be designated so that it will ignore targets outside the box and self-destruct if it passes through the box without finding a target. Multiple rounds can be fired in a salvo, against one or more targets.

Will the US consider it?:

Clearly this weapon is being marketed to the US, including apparently for use on the Littoral Combat Ship as a competitor to an enhanced Griffin. US Special Forces have already shown an interest in the missile.

Diagram source: http://brimstonemissile.com/brimstone/

“BRIMSTONE is also being proposed as a surface-to-surface missile for deployment within the SEA SPEAR self-defence system against FIACs (fast inshore attack craft–Chuck) and other small surface threats. With a range of deck-mounted launcher options, from single to six-pack configurations, the system’s very small footprint gives it a high level of deck positioning flexibility making it suitable for small vessels such as FACs as well as much larger vessels such as auxiliary ships.”

When you have to hit a target, have to hit a budget and don’t have time to waste.

Footprint:

It is relatively small, about 107 pounds, less than six feet long, and approximately seven inches in diameter. They claim it is suitable for vessels as small as 15 meters (50 feet).

Alternatives

The nearest similar missile in US service right now is the Hellfire. Brimstone developed out of a program to improve Hellfire, so not surprisingly, Hellfire is very similar in size but has a shorter range. Hellfire has been used on the Combat Boat 90 (a 52 foot boat). It does not have the sophisticated dual mode guidance and collateral damage avoidance features of the Brimstone. Several types have been built. Most are semi-active laser homing, but there is a millimetric radar homing version also, but it does not include the man-in-the-loop feature of the Brimstone. The model that appears most useful in a naval environment is the “N” model. The Thermobaric warhead does sound interesting.

AGM-114N Hellfire II
  • Target: Enclosures, ships, urban targets, air defense units
  • Range: 8,000 m (8,749 yd)
  • Guidance: Semi-active laser homing
  • Warhead: Metal augmented charge (MAC) (Thermobaric)
  • Weight: 48 kg (105 lb)
  • Length: 163 cm (64 in)

What would we use it for?

New weapons like this are beginning to give even very small craft the punch that once came only with something like a 5″ gun, but perhaps more importantly it allows a very precise application of force. That should be very important to the Coast Guard in that their units are most likely to operating in and around the US including densely populated areas.

This may not be a ship killing, or even ship stopping weapon (although it might help), but it might be useful against a different type of difficult target. We might someday need to stop a terrorist or an enemy in wartime employing a fast highly maneuverable craft operating inshore or among a number other vessels where gunfire is likely to cause civilian casualties. This system would be much safer, and more likely to succeed, than using guns, in that circumstance.

Too good to  be true?

With the possibility of being surrounded, pushing one button, and wiping out all your enemies, I was reminded of this sequence from the movie “The Last Starfighter.”

More info here:
Brimstone Advanced Anti-Armour Missile, United Kingdom

Farnborough 2012: MBDA completes Sea Spear live firing