Monthly Archives: October 2015

Steel Rain: The Greatest Rocket Artillery

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With a fantastic gun artillery system like the PzH 2000, one might wonder why we’d need anything else. Gun artillery is great at providing sustained striking power. To increase the destruction, you need more howitzers and more time, especially considering the cost of modern self-propelled howitzers. Sometimes you need a lot of destruction all at once. Sometimes, you catch the enemy with his guard down, and you really want to hit with a big haymaker and frontload your striking power all at once. For that, you want rocket artillery.

The first big users of (modern) rocket artillery were the Soviets, who used it to great effect against the Germans on the Eastern front. Rocket artillery hit really hard and was pretty cheap, since all you needed were rails on the back of a Studebaker truck. The rockets themselves were pretty simple too. Say what you like about the Russians, but they learn from their successes, and they continue to be a world leader in rocket artillery systems, with their flagship being the BM-30 Smerch. Being blatant copycats of the Russians, the Chinese are also big rocket artillery producers and they currently produce the biggest rocket artillery system available in the 400 mm WS-2. But we’re not talking about either of those systems. No, the best rocket artillery system is the American M270.

The M270 was designed in 1977, when the US Army remembered that the M4 Sherman Calliope rocket artillery was actually kinda helpful, and gee, if those Soviets had so many stupid rocket artillery systems, maybe we should get some too. It’s built on a Bradley chassis that’s been so heavily modified as to be almost unrecognizable. It’s more like the bastard spawn of a Bradley and a flatbed truck. The M270 has a crew of 3, a 500 hp diesel engine, and an operational range of 640 km. It carries twelve 227mm rockets, and can launch them all in under 40 seconds.

Big rockets like the 227mm units on the M270 are designed with cluster munitions in mind. The standard loadout is 644 Dual Purpose Improved Conventional Munitions (DPICM) per rocket. These are basically shaped charge submunitions with a fragmentation shell. The basic rocket has a range of 32 km. Variant rocket types are available with improved range at the cost of fewer submunitions (518 DPICMs and a range of 45 km). Other options include GPS guidance, a big unitary warhead variant, and a variant equipped with the high-end guided SADARM (Sense and Destroy ARMor) submuntion.

SADARM can be fired from rockets or 155mm artillery shells. It works by using a system of parachutes to slow its fall while it scans the area below it with both millimeter wave radar and an infrared optical system. If it detects an armored vehicle, it can be steered toward the target by altering its rate of spin. Once over the target vehicle, it deploys an explosively formed penetrator. It’s pretty lethal, sort of a “quality” alternative to the “quantity” attack option of DPICM.

The big DPICM attack option is pretty formidable. In the first Persian Gulf War, the British found that a single M270 could basically kill everything in a 1 km by 1 km grid square on a general’s map. This is pretty cool, but none of this is really unique to the M270. For those that are cool with cluster munitions still (yes, this includes Russia and China, and Borgundy too), the Russians and Chinese offer rockets of equal size or larger that can carry all kinds of submunition payloads. Satellite guidance is also something they can do, as is fancy guided antitank submuntions.

It should be noted that the big 300mm rockets of the BM-30 and the 400mm rockets of the WS-2 can both carry more submunitions, since they’re bigger. The big advantage of the M270 is that it can also launch the MGM-140 ATACMS short range ballistic missile. It can carry a pair of these instead of the dozen 227 mm rockets. Again, ATACMS can be equipped with submunitions or a unitary warhead, and GPS guidance is available. Not that we’ve tried, but you could put a small nuclear warhead1 in without too much trouble. Range is basically constrained only by the pesky MTCR. So the M270 provides both a standard rocket artillery capability and an SRBM capability in the same vehicle. It’s more or less equivalent to both the Russian BM-27 and Iskander systems, if you could combine those.

Production of the M270 ended in 2003. If there was one unit I’d like to restart the production lines for, it’d be the M270. Maybe we can make a deal, Fishbreath?

1.) The W84 seems like a good choice for a “physics package.” If you wanted destabilizing, anyway.

Resurrected Weapons: ASP-30

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And now another casualty of the end of the Cold War and the “Peace Dividend”. To understand it though, we first need to look at the state of emplacement weapons circa 1980 (or now–they haven’t changed much). By ‘Emplacement Weapon’, I mean something large, movable by a group of men, that’s mounted on a tripod in a more or less fixed position, on a pintle in helicopters and light vehicles, or mounted in a remote weapons station. More specifically, I’m interested in the Browning M2 HMG and the Mk. 19 automatic grenade launcher, and replacing both.

The Browning M2 was designed in 1918, and has seen a long and storied use as an antiaircraft gun, as the armament of the vast majority of fighters in the Second World War, as a pintle weapon, as a weapon for remote weapon stations, as a gunpod gun, and even as an impromptu sniper rifle. It does many things well, like penetrate light armor, and reach out to about 1,800 meters. There are even some pretty fancy armor piercing incendiary rounds available. All wonderful things, but it can’t throw small but useful quantities of high explosive very well. The rounds are too small for that.

On the explosive-throwing front, we have the Mark 19, which was born out of the need for explosives-throwing on the Mekong Delta in 1966. It shoots 40x53mm grenades, which have more velocity than the standard 40x46mm grenades used in underbarrel grenade launchers like the M203. Even so, the grenades fly an arcing trajectory, and aren’t very easy to aim at longer ranges, despite the site having overly optimistic markings out to 1,500 meters. It’s another super useful support weapon, since throwing lots of explosives is always helpful. But wouldn’t it be nice if we could combine the advantages of both? Explosives, armor penetration, flat trajectory, and good range, all in a single weapon.

The ASP-30 promised to do just that. It fired the 30x113mm B round, getting a flat trajectory and effective range out to 4,000 meters on an energy basis. Even when tested on a simple pintle mount, the ASP-30 can match the range of the M2. Due to the relative volumes of the shells, the 30x113mm high explosive dual purpose rounds have about the same amount of explosives as the 40x53mm HE grenades of the Mk. 19. Those M789 HEDP rounds are also capable of defeating the armor of BMP-1s and BMP-2s, which is quite a bit more armor penetration than the .50 BMG. As a bonus, the 30x113mm B rounds are already in the NATO inventory, being used in the M230 autocannon on the AH-64 Apache.

So what do we give up? In a word: weight. The ASP-30 weighs in at 52 kg, which is 14 kilos more than the Mk. 19 or the Browning M2. This hurts mostly on the manpacking front. While more weight is something that needs to be dealt with, the ASP-30 has been tested on vehicles as light as HMMWVs, and as weight-concious as helicopter door gun mounts. It’s a big gun, but it’s workable in vehicular applications. Infantry will have to wrestle with it quite a bit more, probably with a multiple people lugging the big ASP. That said, it’s a really big capability gain, giving a two-for-one deal for light vehicles and as a RWS mounted system for light and heavy vehicles. More firepower, more range, plus it would mean reducing the number of sets of spares that have to be stocked. With savings like that, Fishbreath might even be interested.

Verdict: Approved by Borgundy War Department Procurement Board.

Fishbreath Plays: MechWarrior Online

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The Battletech Kickstarter kicked me back into playing some MechWarrior Online. I ought to note that, on the whole, I like it. I don’t think it quite hits the heights that previous MechWarrior games hit, but it’s a perfectly serviceable stompy robots game in terms of gameplay. That isn’t what this post is about, though.

No, this post is a rant.

Let’s talk about the grind. Oh, the grind. That necessary evil in free-to-play games, right? Yes, but this one is particularly egregious. Fans of the game may try and tell you it’s less grindy than World of Tanks, say, or World of Warships. They are lying to you. Let us be perfectly clear. There is precisely one type of player for whom MechWarrior Online is less grindy than the Wargaming.net games: high-level competitive players. World of [insert vehicle] does indeed require more out of you than MechWarrior Online does if you want to experience what counts as the endgame. I would posit that these players, though, make up such a tiny proportion of the playerbase that their opinions are basically meaningless. Let’s get down to brass tacks with a comparison.

I’m a fairly casual player in World of Warships, and a fairly casual player in MechWarrior Online. As such, my goal in the former is to have a couple of historical Second World War vessels, which occupy (generally) the top half of the tech trees. I need to get to about tiers 4-6. I average about a thousand experience per game, or more if I’m playing primarily for first-win-of-the-day. To go from tier 5 to tier 6 costs about 30,000 experience, which comes to about 30 games. (Going from tier 1 to tier 5 is about that difficult too, if I recall correctly.) It takes me about 60 games—certainly, no more than 75 on a bad streak, and no more than 100 on a horrid streak. So far, I’ve never had to grind for money; in the course of getting through my 60-100 games to hit the next tier, I’ve made enough to buy my way up.

In MechWarrior Online, as a fairly casual player, my goal is to build up a stable of mechs of various sizes and roles I can switch between as the mood strikes me. There are two obstacles here. First, earnings: I make about 80,000-100,000 c-bills per match in MechWarrior Online. A single light mech chassis costs about 2,000,000 c-bills. (A little less for 20-ton mechs, a little more for 35-ton mechs, a whole lot more for mechs which can mount ECM—note that ECM capability usually makes a given mech variant the most desirable of its chassis.) A medium mech costs about 3,750,000 c-bills. You’ll spend between 5,000,000 and 6,000,000 for a heavy, and 7,500,000 to 10,000,000 for an assault.

You begin to see the magnitude of the problem. Buying a light, a medium, a heavy, and an assault chassis takes nearly 20 million c-bills and a shade under 200 games. Outfitting a mech can sometimes double that cost, especially if you don’t have a bunch of weapons and equipment sitting around your mech lab, if you’re a new player. We’re already up to about a 400-game grind to buy and outfit four individual mechs. That’s a big time sink.

It also isn’t the end of it. When you buy a mech, you unlock skill trees for that mech. Consider this: I earn about 800xp per match. If I don’t sink about 30,000 experience into each variant, that variant is between 10% and 50% worse in a variety of extremely important performance measures (speed, heat capacity, turn rate, and more) than someone else’s copy of that variant who has done the grind. That’s a 40-game grind in each mech after you’ve acquired it. I’ll grant you, that comes out to less than you need to acquire the mechs (a mere 160 games), but that isn’t the whole story.

You see, the mech skill trees come in three tiers. To unlock each tier, you need to finish the tier beneath it… on three separate variants of a given chassis. So, you don’t need 400 games and 40,000,000 c-bills to buy and outfit four mechs. You need 120,000,000 c-bills and 1200 games to grind out the requisite twelve variants to avoid being a gigantic drag on your team. More than 400 of those games will be played in mechs that are arbitrarily handicapped in an attempt to get you to buy premium time.

So no, Wargaming.net’s games are not more grindy than MechWarrior Online for the average player. Basically, if you don’t get summers off, you’re going to have to spend money if you want to fill out your mech stable, and a lot of money, at that. I leave gawking at the prices as a trivial exercise for the reader.

Some anti-patterns

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Another college pal, a fellow traveler in the world of the computer sciences, wrote up this list for me. Call him Shenmage, and encourage him to set up the contributor’s account I made him here, the lazy bum. -Fish

As a software engineer, I tend to come across code bases of various levels of quality. To make light of some of the oddities we encountered, myself and some of my co-workers started writing up the logical conclusions of the code structures. Each of these was encountered to some degree or another (though not necessarily as anything beyond a single method). Enjoy, and feel free to add your own to the comments section.

Walmart Pattern

  • Has everything you could ever want
  • You can’t find anything
  • Sometimes have to get multiple of something when you only want one

Sam’s Club Pattern

  • See Walmart Pattern
  • Can only get things in bulk (no single entities)

Titanic Pattern

  • Everything is well structured and coded to the dot
  • Only has a manual process for recovering the system (with potentially catastrophic consequences)

Power of Attorney Pattern

  • Pass SQL commands directly to a web service to get executed

Lottery Pattern

  • Retrievals are randomly generated
  • Only occasionally get what you want

Tardis Pattern

  • Alters history of an object
  • Does more actions than requested
  • Doesn’t do anything exactly as you request

Leaning Tower of Pisa Pattern

  • Perfectly structured but tightly coupled to outdated tech

Starbucks Pattern

  • More identical web services than you need
  • Expensive computationally

Monopoly Pattern

  • Multithreaded, but one thread eventually eats up all available resources

Glass House Pattern

  • Security on a system was completely ignored on critical components

Magic 8 Ball Pattern

  • Calls return only boolean values
  • ‘Maybe’ is included as a boolean value
  • Multiple ways to say each value

Speakeasy Pattern

  • Webservice is completely undocumented, so have to know precisely what to send where to use it

Narcissus Pattern

  • Class depends upon itself and uses itself to accomplish tasks

Lazy Inspector Pattern

  • Methods that should do tasks instead return true

Scorched Earth Pattern

  • Update method drops and recreates table

“What’s in the box?!” Pattern

  • Large, untyped, container objects are the only objects passed around the system

OCD ORM Pattern

  • Verifies all retrievals by retrieving again

M2 Bradley Part 3: Modern Competition

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Okay. I’ve talked about the Bradley’s massive firepower, and the many proposed variants that never actually entered production. I’ve mentioned that it compares pretty favorably to modern competition, but let’s actually give that a go. Let’s compare the Bradley to a modern IFV; specifically the CV9035 IFV. We’re going to try to keep this to a head to head between the two vehicles; we’re not going to try to compare the variants-that-might-be. For clarity, note that we’re looking at the M2A3 Bradley.

The Bradley wins the firepower shootout pretty clearly. The Bradley has significantly more ammunition available for its coax machine gun (both feature a 7.62x51mm GPMG coax), and features a twin-tube TOW missile launcher in addition to the 25mm autocannon, giving it an antitank punch (albeit an outmoded one). Let’s take a look at the autocannon though. This is as good an excuse as any to compare the two autocannons. The M2A3 carries 300 rounds of 25x137mm ammunition in it’s ready stowage magazines. One is for 67 rounds, one is for 133 rounds. The CV9035 carries 70 rounds of 35x228mm ammunition in it’s two 35 round ready magazines. Clearly the Bradley wins the “who can shoot longer without reloading” game, and the combat persistence of the Bradley has proven useful in Iraq. On the other hand, the 35mm gun is much better at penetrating armor. The best unclassified1 penetration data I have gives the 25mm M919 DU APFSDS round the ability to penetrate up to 100 mm of rolled homogeneous steel armor (RHA) or equivalent stuff. The 35mm can penetrate up to 130mm of RHA, and this is without using depleted uranium in the penetrator round. So the 35mm is going to be significantly more useful against more heavily armored vehicles, including other Western-made IFVs as well as the rumored BMP-3s with heavier armor. Not using depleted uranium yet means that 35mm has some growth potential left to help keep pace with future threats.

Let’s look at high explosive next. This is the more generally useful capability for an IFV. The 25mm HE shell has a weight of 180 g. The 35mm HE shell has a weight of 550 g, or about 3 times the mass. However (presuming the larger of the two magazines on the Bradley is loaded with HE), the Bradley carries about 3.8 times as many HE rounds as the CV9035. So, there’s a net HE weight advantage for the Bradley, and one might consider that the question comes down to the simple matter of whether one prefers more rounds or big rounds. But, being larger as well as used in many air defense applications, there are some wonderfully fancy fusing options available for the 35mm. These include the “3P” (Programmable, Proximity-fused, Prefragmented) as well as a hybrid KE/HE round called NR468 KETF (Kinetic Energy Time Fused), which sprays tungsten pellets. The bigger shell size gives designers more to work with, and more options are available.

One other thing is worth noting here. Most tracers on 25mm rounds burn out by the time the round gets about 2 km downrange, which makes it difficult to observe the fall of shot and score hits on further targets. The 35mm round does not have this problem, and Danish CV9035s have scored hits from beyond 3 km in Afghanistan. So, while the Bradley has the edge in firepower, there are a number of advantages to the 35mm gun on the CV9035.

Protection and survivability go hand in hand, and are both won by the CV9035. It has significantly better armor, using modern MEXAS composites that provide it with superior protection against both shaped charges and long-rod penetrators. The CV9035 underbody is designed to provide some measure of protection against mines, whereas the Bradley has a rather thin underbelly. In terms of supplemental protection, kits are available for both vehicles. The CV9035 should be better able to handle the extra weight in this area, since it’s a newer vehicle with a less heavily loaded suspension.

Survivability is more or less the flip side of the Bradley’s advantages in firepower; it’s packed with five TOW missiles, three AT4 rocket launchers, and 600 rounds of 25mm ammunition. The Bradley also lacks spall liners, and ammunition isn’t separated from the crew compartment. As such, it burns notoriously well. The CV9035 stores its smaller amount of ammunition in a safer fashion, and as a result it’s much less vulnerable to secondary effects. So the big2 Swedish vehicle is a safer vehicle for its crew and passengers.

Capacity on the CV9035 is a little vague, because different internal configurations. Ad copy from BAE-Hagglunds gives a capacity of 7, though I have some other sources3 that say 8. The M2A3 holds 7, though that last seat behind the driver is somewhat cramped. Possible slight advantage to the CV9035, but I’m about as willing to call this a wash due to uncertain sources.

Electronics fit is also a wash. Both the M2A3 and the CV9035 have fancy modern battle management systems, thermal imaging sights for the gunner, independent commander’s thermal imaging sights to provide a hunter-killer capability, and backup cameras to aid in administrative driving. There is, of course, the usual encrypted radio fit.

Despite similar weights, the CV9035 has significantly better mobility. It’s got a more powerful engine (755 hp as opposed to the 600 hp of the A3 Bradley), and the CV9035’s suspension is designed to handle soft ground (or snow) well. In Norwegian tests, the CV90 proved to have the best mobility of any IFV tested, beating out the Warrior 2000, the Bradley, and the Puma.

So where does this leave us? Well, despite the superior firepower of the Bradley, the CV9035 is as good or better in every other area. Once again, the CV9035 beats out a flashier opponent as the better buy. It does more things better, has more growth room left in its design, and is reasonably priced. I would also add that the CV9035 is probably not better enough to justify an upgrade if one already had Bradleys. But this is a showroom comparison, not a ‘should we upgrade’ article.

Interestingly, despite all of the many Bradley variant proposals, the CV90 series gives more options of things actually in production now (compared to the Bradley production line as it was when it was stopped). There’s the CV90 Armadillo, which is a turretless APC variant. There’s also the CV90120, which is a modern take on the Tank Destroyer/Assault Gun concept, being well armed but lightly armored. Finally, there’s the CV90+AMOS which features a turret with a pair of automatically loaded 120mm mortars for a very powerful short range indirect punch. The most interesting Bradley variants never made it to full rate production.

1.) While these are almost certainly not correct, I expect them to be reasonably close. Also, for most mature systems, I figure they’re all going to be off for similarly classified reasons, i.e. I figure they should be off by about the same amount and so make good comparison metrics.
2.) Seriously, this thing is bigger than a Leopard 1 tank. Ask me if I care.
3.) Including my copy of Jane’s Armour and Artillery, 2008-2009. It’s old because those books are damned expensive. I wouldn’t be opposed to someone gifting me a more recent copy though.