Monthly Archives: July 2018

AU-220M, a New 57mm turret

At IDEX-2015, Russia unveiled the AU-220M, a turret for a 57mm gun, designed for IFV mounting. Let’s take a look:


It’s unmanned, holds 200 rounds of 57mm, and has a coax 7.62mm gun with 2,000 rounds of ammunition. It’s been mounted on a couple BMP-3 prototypes, and demoed at some Russian trade shows.

I don’t like it and neither does Fishbreath. Congratulations, you’ve built an IFV-destroyer. It’s like an old tank destroyer, but the gun is too small to threaten a tank from the front. It can threaten an MBT from the side, but 30mm is generally enough to do that as well, especially since supplemental armor packages are focused on shaped-charge threats. The Russians are also usually very good about adding modern ATGMs to their IFVs.

On the BMP-3 in particular, this is both an annoying design challenge and a firepower lateral move. I’m not convinced that this is an appreciable firepower improvement over the 100mm low velocity gun and 30mm autocannon that’s already mounted. The 100mm gun can already fire missiles that will be problematic for IFVs but will have trouble killing tanks, and that’s a bigger HE option.

The AU-220M is also problematic from a vehicle engineering perspective. It has a large turret basket that eats internal volume, just like a manned turret. But it’s unmanned. You have to relocate the vehicle commander and gunner somewhere else in the crew compartment. As if it wasn’t cramped in there already.

So there you have it folks. We’re not a fan. And I haven’t seen it on any production vehicles either. I’m certainly not going to lose any sleep over it.

Fitting Out a Fantastic Burke

The Arleigh Burke class guided missile destroyers are the best exemplar of the type currently at sea. They are among the few truly multirole ship classes, able to perform any duty one might reasonably ask of them. Despite the design approaching its thirtieth birthday, the US Navy is continuing to build them, and they’re reasonably popular on the export market. With such a long life comes plenty of upgrades and options, so let’s see how we’d fit one out. DDGs, nicely equipped. One small note before we dig into this: I’m going to limit myself to features proposed or actually fitted to Arleigh Burkes, not hypotheticals like putting the SPY-3 radar on one.

Hull Variations
First, we have some decisions to make about the hull form. We’re going to take what I’ll term the “large form” hull, which was originally designed in the early 90s as the “Flight III” variation.1 This version was cancelled, but the design got used in the South Korean variation of the Arleigh Burke, the Sejong the Great class. This means an increase in length of 32 feet 4 inches, an increase in beam of 4 feet 3 inches, and 32 additional VLS tubes, for a total of 128.

Radar Systems
The radar is a critical system on a DDG. A long range radar allows for the tracking and engagement of multiple targets, which is important for the survival of the ship, plus any others she’s escorting. Radar is key, so we’re going to get the best and latest: AN/SPY-6. SPY-6 is an actively scanned phased array, unlike the passively-scanned SPY-1D fitted to most Burkes. The SPY-6 is more sensitive, can track many more targets, is more resistant to ECM, and might have the possibility of being a jammer in its own right. Super cool. It also provides solid ballistic missile defense capabilities.

But that’s not enough. While the big SPY-1/SPY-6 radar is the most prominent, there are other radars that complement it to provide better capabilities for the Aegis Combat System. A new and fancy radar is in the pipeline to compliment the SPY-6, but development hasn’t been completed yet, and the initial Flight III ships will start with integrating only the new SPY-6. Currently, the standard companion radar is the AN/SPQ-9B. It’s an X-Band suite optimized for tracking ships and low flying aircraft2 in littoral regions. It can also provide terminal guidance. I would like to see a more advanced system replace the SPQ-9B, but I’m very happy the US Navy is upgrading one system at a time.

Burkes have been fitted with most western CIWS. Phalanx, Goalkeeper, RAM, and SeaRAM. We’re going to focus on the missile-based systems, since I’m a huge fan of the RIM-116. The choice comes down to launcher. The Mk. 49 GMLS has a 21-tube system, but requires external fire control information for cueing. The SeaRAM system has a capacity of 11 missiles, but comes with the radar and IR sensors used in Phalanx Block 1B, so it’s completely autonomous. Personally, I think I prefer the Mk 49, given that we already have an excellent radar suite. However, I could be swayed if the data exists showing that a separate radar on the CIWS is the better bet.

Funnel Structure
No option is too small for us to consider. There are a few different funnel designs on the various Burke flights. We’re going to go with the newer design that extends the external funnel structure up to the level of the exhaust tops. This reduces signature a little, and every little bit helps. This particular design element was first introduced on USS Mustin (DDG-89).

The AN/WLD-1 Remote Minehunting System (RMS) is an unmanned underwater vehicle that allows minesweeping operations without putting the mothership at risk. Mines are a huge and underappreciated threat, and this is a welcome addition. Fitting the RMS requires some amidships structural changes to accommodate the launching, recovery, and storage of the UUV. Part of these are moving the triple 325mm torpedo tubes from the main deck amidships to the missile deck aft. These modifications can be seen on some of the US Navy’s newer Burkes including USS Momsen (DDG-92).

Unsurprisingly, we’re selecting the aft helicopter hangars. Helicopters are good. I’m really not sure why early Burkes didn’t come with actual aviation facilities, but that was the decision someone in the Navy made. This puts in hangars with space for a pair of Blackhawks aft.

Sonar Systems
For our towed array, we’ll opt for the SQR-20 MFTA. It has both active and passive sonar systems, and offers improved reliability, coverage, and detection capability over the previous standard SQR-19. Bow sonar will be the SQS-53C.

I really don’t care much about the naval gun. It is not a key capability of the ship. My choices are all 5″ guns, given my constraint that I can only select from existing options. If I could put a 76mm up front to save cost and space, I would. But I can’t. So we’ll take the Mk 45 Mod 4 gun. Good enough.

That covers our standard options for our Burke. They should do well.

  1. I’m not sure if this will be used on the upcoming-production flight III ships or not. 
  2. Aircraft meant in the loosest possible sense of the word, so airplanes, helicopters, uavs cruise missiles, antiship missiles, et cetera. 

2018 IFV Roundup

In the spirit of my revisiting of MBTs in 2018, let’s also take another look at IFVs. Happily, this field is a little more saturated, and has some interesting options available.

Of course, I’m also not about to throw away perfectly good data. The Czechs looked at ASCOD 2, Lynx, Puma and two versions of CV9030 (one with a manned turret, one with an unmanned turret). That’s most of the in-production contenders from the West. So let’s see which won what and go from there, shall we?

And then the Puma swept the competition. It had better reliability than all other test vehicles, being the only one not to have to repeat a test due to a breakdown. It has better protection than its rivals. It has better mobility than its rivals too. And, while all vehicles were armed with a 30mm gun, the Puma was significantly more accurate. The Puma had 37 hits out of 40 shots fired, and the next-best competitor did about half as well.

That’s pretty good. However, the Puma is the most expensive of the lot, and the Czechs might like to look at some other variants besides a pure IFV. They may end up buying Puma IFVs and something else for the more utility-type roles.

Of course, I wouldn’t just write a new roundup to simply say, “I agree with the Czechs.” Even though I totally do. Of the vehicles tested, the Puma has proven to be tops. Best by test. However, the Israeli Namer IFV was not in the test (certainly its present form wasn’t ready yet), and that’s worth a look. And, as always, we’re assuming both are available and marketed.

First, a brief run down of Puma. The Puma weighs 43 tonnes with all armor modules installed. Some modules can be removed to permit the Puma to make weight for transport in an A400M. It has a 30mm autocannon with 200 rounds of ready ammo, a 5.56mm1 machine gun with 1,000 rounds of ready ammo, and a two-tube launcher2 for Spike ATGMs. It has a crew of three and carries six dismounts. It has an MTU 890 V10 engine that makes about 1,100 hp. It exceeds STANAG level 6 protection on the front, meets level 6 on the sides (the highest level for KE threats), and makes STANAG 4 on the bottom against mines (confusingly, level 4 is the highest for mines). It also has an integrated soft-kill active protection system (i.e. a DIRCM). Annoyingly the STANAG levels for KE protection make no mention of what sort of shaped charge threats they can counter, and there’s no separate scale for that either.

And now for Namer. Namer weighs about 60 tonnes in its APC form, and the Israelis haven’t updated the approximation for the IFV version. It has a 30mm autocannon with 400 ready rounds, a 7.62mm machine gun with 700 ready rounds, two Spike ATGMs, and a 60mm mortar. The turret also comes equipped with the Trophy hard-kill active protection system. Namer has a crew of three and carries nine dismounts. Namer is powered by a 1,200 hp AVDS-1790 engine.

For the Namer, the Israelis haven’t released information on its protection level (and STANAG only goes up to level 6, which is merely being able to stop 30mm APFSDS), so we’ll have to guesstimate. Namer weighs about as much as a Merkava, but it lacks Merkava’s big tank turret. The Israelis say they’ve put the weight into protection, which makes sense. There aren’t many other places where that weight could go. Also, the APC version of the Namer has been shot at with Kornet missiles in Lebanon. Kornet is a modern Russian ATGM, but it was not able to penetrate the frontal armor. It did penetrate the side armor, but did not harm any of the soldiers inside. This is pretty impressive, so I’ll give a win to Namer in the protection category.

Firepower is mostly a wash. The Namer has twice as many ready rounds, but I don’t have a good notion of how many we can expect to use in an engagement before resupply. So I don’t know if it actually matters. Both have a pair of Spike ATGMs. We haven’t seen a comparative test between the two, so we don’t know if one or the other has an accuracy advantage. Namer also comes with a mortar. I’ll give it a firepower edge, conditional on the lack of head-to-head shooting competition.

In terms of mobility, the Puma is the clear winner. It has only 100 less horsepower while being several tonnes lighter. There were notions of putting the 1,500 hp MTU 883 in the Namer, but that hasn’t been done yet. We would like to look into this as well. The Puma is also easier to move to the battle by far. Again, it is lighter, and armor modules can be removed to get it in an A400M. The Namer is going to have to be transported with one’s tanks. Clear win for the Puma in both strategic and tactical mobility.

Tactical mobility is always to be prized. In the case of strategic mobility, it can also be quite useful. Here, however, I am not so sure. As I have commented previously, IFVs should operate in conjunction with tanks. Deploying tanks in quantity somewhere is going to require naval transport or rail transport or both. And if you’re already doing that for the tanks, you may as well load the IFVs on there too.

For me, this is not a hard choice. I like Puma, but I like the Namer more. I like carrying nine dismounts, and I like having as much (or more) armor on my IFVs as on my tanks. Yes it’s heavy. That’s why we call them Heavy Brigades, right?

  1. Plans have been announced to replace this with a 7.62mm MG, though they’re not finalized yet. In any case, this would be easy enough to have done. 
  2. Integration and testing are in progress. We’re seeing these actually on demo vehicles now which is good. Nothing like a client to move the ball faster. 

Lewis and Clark Class Dry Cargo Resupply

Warships are cool. Warships are sexy. But if you want those warships to project power beyond your shores, you have to keep them resupplied. Let’s look at some of the ways the US Navy keeps its ships supplied. We’ll start with the Lewis and Clark class Dry Cargo Resupply ships, known by the hull code T-AKE.

The Lewis and Clark class are 689 feet long, 105.6 feet in beam, and have a design draft of 29.9 feet. They displace 41,000 tons and are designed to handle up to 6,005 tonnes or 783,000 cubic feet of dry cargo, plus 2,390 tonnes or 18,000 barrels of fuel. of the 6,005 tonnes of dry cargo, 1,557 tonnes are refrigerated storage. Dry cargo can include ammunition, frozen and dry food, consumables, and spare parts. The T-AKEs are equipped with US Navy Underway Replenishment equipment, and can resupply any US or allied vessel that is equipped with same.

The T-AKEs are all-electric ships, generating power with four diesel generators. They have one electrically-driven screw, plus a bow thruster for maneuvering in port. The electric drive system can propel the Lewis and Clark class ships at speeds of up to 20 knots. Electric power is also used to run the Automated Storage and Retrieval System (ASRS). ASRS can work with any standard container, will retrieve containers in weather up to sea state 5, and will survive undamaged in weather up to sea state 9.

The Lewis and Clark class have a crew of 124 civilians and 11 naval personnel. A mostly civilian crew is what gives the ships the “T-” prefix on the hull type classification. At present, the T-AKEs do not have any active means of self defense, but there is space and topweight available for CIWS if this is desired in the future.

Also of note is that the T-AKEs are generally built to civilian standards, with some additions for increased survivability. This was to reduce costs, bypass any potential bottlenecks, and to produce a design that would also have a lot of marketability to the civilian merchant marine.

NSWC Crane Likes Midlength Gas Systems

These days the US miltary favors M4s with 14.5″ barrels and carbine-length gas systems, which is to say, a gas port located approximately 7.8″ in front of the bolt face. It works. On the civilian market, lots of companies are offering (usually pinned) 14.5″ barrels with the midlength gas system, i.e. gas port about 9.8″ ahead of the bolt face. Civilian shooters will tell you the midlength gas system is a softer shooting system. But is it more reliable? We could make arguments about it, but NSWC Crane decided to put it to the test.

Barrel Wear: Accuracy Degradation
In a normal, carbine-length gas system, a degradation of accuracy can be seen after about 6,000 rounds. Crane’s testing found that after 12,000 rounds, the midlength barrels did not suffer appreciable accuracy degradation.

Muzzle Velocity
Does the midlength gas system cause any loss in velocity? In the unsuppressed case, the carbine had a mean muzzle velocity of 2,905.4 feet per second, and the midlength had a muzzle velocity of 2,906.4 feet per second. The difference in means is -1.0 feet per second, or 0.04%.

In the suppressed case, average muzzle velocity was 2,989.7 feet per second for the carbine system and 2,983.0 feet per second for the midelength. Here the difference is 6.7 feet per second, or 0.23%. In either case, muzzle velocity is negligible.

Terminal Velocity (100 yards)
Given the negligible difference in velocity at the muzzle between the carbine length and midlength gas systems, we would expect the difference at 100 yards to be similarly negligible. And it is. In the unsuppressed case, carbine-length gas system yields a terminal velocity of 2,635.9 feet per second and the midlength gives 2,677.6 feet per second for a difference of 41.6 feet per second or 1.57%.

The suppressed case is similar, with the carbine-length gas system providing 2,654.1 fps and the midlength providing 2,686.7 fps, for a difference of 32.6 fps or 1.22%. Overall, there’s not much of a performance difference. Midlength is actually slightly better. Of course, we wouldn’t expect much of a difference in velocities from changing the gas system length.

Cyclic Rate
We might expect a change in cyclic rate from altering the gas system length (and hence the gas pressure in the system). Also, small reductions in cyclic rate tend to be good from a parts-life standpoint as well as a controllability standpoint. So what do we get? Again, we have the suppressed and unsuppressed cases. In the unsuppressed case, we see a reduction of 127.2 rounds per minute or 15.9% going from a carbine-length 864.8 rpm to a midlength 737.6 rpm. The suppressed case gives us a reduction of 62.7 rounds per minute or 6.9% when we go from a carbine-length 944.2 rpm to a midlength 881.5 rpm.

Given the reduced cyclic rate for the midlength, does this translate into more reliability? The tests showed that it did. The carbine length gas system had 65 stoppages, and the midlength gas system had 30. The high temperature (160 F) testing phase accounted for 5/65 stoppages in the carbine-length gas systems and 1/30 stoppages in the midlength gas systems. Low temperature testing (-60 F) accounted for 27/65 stoppages in the carbine-length gas systems and 15/30 stoppages in the midlength gas systems. All other stoppages occurred in ambient-temperature testing.

So now we have some hard data proving that midlength gas systems are better on 14.5″ barreled weapons. Great! This gets more interesting because the USAF is looking at buying 50,000 improved M4s for security forces, battlefield airmen and OSI. That’s the kind of significant buy that can have an impact on what kind of weapons the rest of the US armed forces use. Remember, the Air Force were the first to embrace the M16.

The Crossbox Podcast: Episode 27 – Armed Services Salute

In a summertime edition of The Crossbox Podcast, we find an excuse to play some of our favorite military music: talking about procurement challenges service branch by service branch.

Further reading
* America and Wasp deck plans, compared, in which your host looks foolish for not realizing they’re the same size.
* Parvusimperator likes the F-35
* The Drive on the B-21 (see also sweet B-2 flyby GIF)
* The M14 is crap
* FFG(X) contenders

Continue reading


Despite being designed in 1960, the M113 has remained popular. It’s a big, tracked aluminum box. So it’s easy to fit stuff in. And lots of things can be put in a nice aluminum box. Lots of these, like command vehicles, mortar carriers, ambulances, and the like aren’t frontline vehicles. So the M113’s increasingly marginal protection wasn’t that much of a concern. It’s adaptable and low cost. But there’s not a lot of weight capacity for more protection if the vehicle is to be used in urban operations, and the powerplant is pretty old.

Enter FFG. FFG cut their teeth upgrading old M113s, and they finally figured they might be able to offer something better. This is the PMMC G5, seen below.


The G5 is actually somewhat larger than the M113, having a payload capacity of 14.5 cubic meters, as opposed to the M113’s 8.3 cubic meters. Where the M113 can handle 2.4 tonnes of payload, the G5 can handle up to 8.5 tonnes of payload. Gross vehicle weight of the G5 is 26.5 tonnes.

The G5 also has a semimodular design. The modules have a floor and roof, plus internal stuff, and can be switched out with a crane. It’s not quite as modular as Boxer MRAV, but it’s still a solid feature.

The G5 faces stiff competition, being somewhere in between a full-featured, turretless derivative of an IFV like the CV90 Armadillo or simpler M113 refits. The PMMC G5 has only been entered into one procurement contest, in Denmark, where it lost out to the Mowag Piranha V.

As for what I think, I am a fan of the concept. Whether or not I’d go with it for Borgundy really depends on cost compared to some other options, and the sort of boring details of proposals that never gets leaked. Specifically, how the cost of a cheap additional vehicle plus spares compares to additional variants of more expensive vehicles (plus more of the spares that you’re already ordering).

Reconsidering the LCS

Editor’s note: Fishbreath and I aren’t fans of the LCS, but he asked me to defend it and I can hardly resist such a challenge…

The LCS is a curious sort of ship. There are two classes, the Freedom-class and the Independence-class, and I’m going to group them together for the purposes of this discussion. They are both very fast, lightly armed, and carry a helicopter. They have some swappable mission modules to enable them to carry things like Hellfire missiles. Their only air defense system is a launcher for the RIM-116; a close-in weapon.

One is immediately struck by what the LCS don’t have. They don’t have a fancy towed sonar array. They don’t have a fancy bow sonar array. They don’t have a bunch of lightweight torpedo tubes. They don’t have antiship missiles. They don’t have a “proper” SAM system like SM-2/3/6, Aster, or ESSM. One might think of them as stripped down Oliver Hazard Perry-class analogues, but this might be frustrating. The Perrys are the quintessential Cold-war era multirole frigate. One might also look at all of the other ships called frigates these days and despair about the LCSes. They are underarmed!

Or are they? Let us first ask what mission we might have for the LCSes. Mission ought to drive the ship design. The Perrys were designed as escorts. Second-rate escorts: intended to protect the anticipated convoys running supplies and war materiel from North America to Europe in the event of a Cold War gone hot. As such, they have an antiaircraft armament of one Mk. 13 single-arm launcher for the SM-1. They also have a towed sonar array and some lightweight torpedo launchers, plus hangar facilities for two helicopters. On paper they’re much more capable ships.

However, one of the things we note is that from 2004 to 2005, the US Navy removed the Mark 13 launchers from the Perrys that remained in service. Why? Well, clearly removing the system reduces ongoing support and maintenance costs. Plus, it’s not really all that useful. The SM-1 missile and Mark 92 fire control system is grossly inadequate against modern threats. The CIWS is going to be able to (probably) handle a single inbound antiship missile fine, and anything serious attack is going to get past SM-1 and CIWS.

The Falklands War showed all manner of problems with the Type 42 destroyers. These were built for air defense, but they suffered badly at the hands of the Argentine air force. The Argentine air force used Exocet antiship missiles and the sort of unsophisticated, low-level, unguided bombing attacks one might see in the Korean War. There were problems with target prioritization, being sure that no target was left unengaged by the multiple firing ships, and ships fouling each other’s radar fixes. The Perrys were even less optimized for anti-air warfare than the Type 42s.

Anyway, the LCS-as-frigate comparison seems to be assuming implicitly that we have to have nice, simple ship types: cruisers, destroyers, and frigates, and proper navies have all three. We have Ticonderoga-class cruisers, which are built on Spruance-class destroyer hulls and are smaller than Arleigh Burke-class destroyers. Let’s unpack those a little more. There are currently 22 active Ticos, each with the Aegis combat system and 122 VLS tubes. There are 65 active Burkes with three under repair, four under construction, and five more on order. Each Burke has an Aegis combat system and 90 or 96 VLS missile tubes. Taking active hulls only, that’s a total of 87 Burkes and Ticos, which I’ll collectively (and imprecisely) refer to as “Aegis ships” for simplicity.

The Aegis ships are fantastic escorts, since they all have powerful radars, computer coordinating systems, communication networks to chat amongst themselves, and lots of missiles. Each VLS tube can hold one of the Standard family of SAMs or four ESSM SAMs. In terms of dealing with air or missile attack, they are the best ships available. They can protect themselves and something nearby. Like a carrier. We have 11 supercarriers, plus nine more straight-deck “Baby Carriers” of the USMC. So if they all were at sea at once, and all operating separately we’d have about four Aegis ships per flattop. That’s pretty good. The Royal Navy would like to be able to do that, and we’d have way more missile tubes per flattop than they would, even if they could manage four escorts per flattop.

Of course, the Mk. 41 VLS tubes on the Aegis ships can carry other missiles as well, including Tomahawk Cruise missiles and LRASMs, giving the ships a potent land attack or surface strike capability. It’s pretty easy for a task force commander to lob an awe-inspiring number of cruise missiles at some tin-plate dictator we hate while having enough SAMs to protect the fleet. For comparison, look at the positively lame ground attacks from the Russian navy deployed to Syria. They wish they had “Aegisski” ships with tons of VLS tubes to lob cruise missiles at their enemies.

In the Aegis ships, the USN has a large number of highly capable surface ships that are truly “Do-everything” ships. They can do any mission you please, and can be configured to do all of them reasonably well at once. No 4-5,000 ton frigate can do likewise. They tend to have 16-32 VLS tubes and a much less powerful radar. These ships tend to carry a mix of quadpacked ESSMs and standard missiles, or foreign equivalent systems. They can do some amount of air defense, but mostly just of themselves. It’s not clear what adding a bunch of ESSMs is going to do to the already formidable air defense umbrella in a US Navy carrier battle group.

Lets also stress that, while we could argue about the most cost-effective mix of ships, the 87 Aegis ships mentioned earlier are already purchased. We have them. They’re ours. Spending a bunch of money on redundant capabilities is silly, and that seems to be what most want to advocate for.

What the Aegis ships aren’t is cheap. They have high operating costs, and there’s plenty of flagwaving missions or antipiracy operations that could be done by a ship without all the fancy, expensive bells and whistles. Playing “Plane guard” and fishing pilots who had to eject from a botched carrier landing doesn’t require a fancy radar or lots of missiles. Hunting pirates off the horn of Africa doesn’t require any fancy systems either, just seakeeping. So the best compliment for a big fleet of highly-capable Aegis ships is a bunch of austere, cheap-to-operate corvettes with good seakeeping.

Good seakeeping is important, and is the major cost driver. Seakeeping is a function of structure, and I’m being imprecise and lumping in range as well. America, as you probably know, is separated from regions of trouble by large oceans, and anything sent to those troublesome regions has to first cross those pesky oceans. And yes, seakeeping eats up space that could be otherwise filled with weapons. If our ships could sail ten miles from our coast and find trouble, we could pack them to the gills with weapons and not care how stable they are. But that’s not the situation we find ourselves in. So no, we can’t just build a few Pegasus-class fast attack craft and call it a day.

So that is how we get to the LCS, more or less. It has a deck gun, a SeaRAM installation, and a helicopter hangar. It can accept a few other mission modules. It can handle a number of basic tasks, including to sail to not-so-hot regions flying an American flag. The one thing I don’t get is the overly high top speed of the ships. I wouldn’t have designed that in, since it drives costs up. Even so, they’re good ships for what they’re designed for: complimenting the rest of our highly-capable surface fleet.