NS Military Realism Consultancy Thread Mk X Purps Safe Space

[Desena]

How big of a difference can a suspension system make in combat for AFVs? I don't know much about automotive design. I see that most tanks seem to use torsion bar suspension, while others like the Leclerc and Challenger 2 use hydropneumatic suspension. Do they have any advantages over the other, or is it just different means of accomplishing the same thing? Are there any other suspension systems for heavy military vehicles, or is that it?

[The Akasha Colony]

How big of a difference can a suspension system make in combat for AFVs? I don't know much about automotive design.

A lot. It's one of the most important factors in determining a tank's safe offroad speed and mobility, alongside power to weight ratio and ground pressure.

I see that most tanks seem to use torsion bar suspension, while others like the Leclerc and Challenger 2 use hydropneumatic suspension. Do they have any advantages over the other, or is it just different means of accomplishing the same thing?

Torsion bars are by far dominant because they provide good performance while also being quite cheap. During WWII there were a whole host of different suspension types in use ranging from the volute springs used in the M4 Sherman and other American tanks to the leaf springs used in the Panzer IV, the Horstmann suspension used in British AFVs, the Christie suspension used by a number of Soviet tanks, and the torsion bar system which was just coming into use (there were other types in use too, these are just a few). Torsion bars are good because they can handle very heavy weights, are quite durable, are relatively compact, and are rather inexpensive. In particular, their ability to handle very heavy vehicles and their simplicity made them displace most other suspension types after WWII. But their disadvantages are that they eat up vertical space in the vehicle because they need to be installed in the hull and this also makes them potentially difficult to replace when damaged. At the time they were introduced, tanks also often had floor escape hatches and the run of torsion bars beneath the fighting compartment meant that these had to be eliminated, but nowadays this isn't much of a problem because such hatches would be a big liability to mines and IEDs anyway.

Hydropneumatic systems are better than torsion bars because as an active suspension, their spring rate, travel distance, and other parameters can be changed on the move. A torsion bar is a fixed spring and thus cannot have its spring rate changed (although its position can be adjusted manually), but a hydropneumatic system allows things like ride height to be changed at the push of a button by the driver without ever leaving the vehicle. Modern hydropneumatic systems allow the vehicle to adjust its suspension to "lean" forward, backward, or even side to side if desired, allowing a tank to increase its gun elevation and depression. They also provide superior ride quality and do not take up any space in the vehicle; they can be bolted to the exterior without any need for the sort of hull penetration torsion bars require. But because they're active, they require hydraulic pumps and a hydraulic system, which makes them much more expensive and more maintenance intensive.

Are there any other suspension systems for heavy military vehicles, or is that it?

There are, but torsion bars and hydropneumatic are the most relevant for modern AFVs. The Israeli Merkava still uses a helical spring suspension which by all accounts works fine but doesn't have any strong advantages over a torsion bar system.

There are some tanks out there that have mixed torsion bar and hydropneumatic suspensions, usually to get some of the advantages of both. The South Korean K1 88 has hydropneumatic units on the front and rear wheel arms and torsion bars on the middle arms, allowing it to lean forward and backward but not reduce its ride height. This is advantageous because Korea is very mountainous and good elevation and depression are important for mountain fighting. The Japanese Type 90 has a similar system for similar reasons. Both though are expected to be at least partially replaced by new tanks with all-hydrpneumatic systems.

[Dostanuot Loj]

There's only one hyperbar engine in the world, so it's not like there are a lot of examples floating around out there. Hyperbar is a specialized system so it hasn't seen any applications outside of the one it is presently used for. It's not good for fuel efficiency which is why it's of little commercial interest. It's of interest to the French because it helped them create a 1,500 horsepower V-8 diesel rather than a bigger V-12 engine, but this came at the cost of fuel efficiency.

Technically speaking there are about a dozen different existent hyperbar engines, but the V8X is by far the most numerous. The rest are testbed engines to develop it, and a few commercial engines which have seen extremely limited applications. I saw one two years ago at a local shipyard that was using it in a private speed boat. I'm pretty sure they are all built by Wärtsilä though.

The hyperbar actually decreases engine fuel consumption for general use, and this is a large reason the French went with it. The diesel engine can be run without the gas turbine running to provide adequate power for normal operations while the gas turbine can spool up quickly to provide appropriate manifold pressure for relatively instantaneous power. It acts much more like a conventional supercharger in how the engine responds without the downside of reduced high RPM drop in efficiency, or the loss of direct power to run the supercharger. It's a great way to beat both turbo lag and supercharger drop almost completely. The only other system which has ever come close to this has been a proper twincharging system, which retains the power sap of the supercharger and is not as good as hyperbar at what it does. The downside of course is that once that turbine kicks in the fuel consumption goes up.

An interesting thing to note is that the Japanese have done exactly the same thing as the French, but gone the mechanical route with a twincharger setup instead.

Opposed-piston engines for tank use in general though haven't been a smashing success. Their compact size has made them attractive but the high operating pressures needed to squeeze the maximum power from their displacement has often negatively affected reliability. The Leyland L60 in the Chieftain is a particularly good example, and the 5TDF and 6TD engines used in the Soviet T-64 series and its successors have had problems as well. A hyperbar would only exacerbate this situation by increasing the pressure even further; I can't find any reference to the 5TDF or 6TD being turbocharged at all (compared to the competing V-2-series diesel in the D-72 which has turbocharged variants).

5TDF, and I presume 6TD (I can look it up) is a turbocharged two-stroke engine. It actually runs two mechanical hybrid style turbos that are connected to the crankshafts like a supercharger in reverse. The turbo compressors are smaller than the turbines allowing for faster spool up and intake pressure maintenance. Excess energy from the turbine (or rather, exhaust gasses) can be shunted into the crankshafts to give a boost directly to the engine from its own exhaust gasses. This is, of course, less than you would get with a larger compressor simply pushing more air into the engine, but does allow the engine to have a quicker response time and reduce maintenance or development issues associated with more air. It's quite the interesting little system.

there aren't any

but that doesn't mean it can't be done

L Y R A N A R M S

You mean:
G U A R I T A

Hyperbar vs opposing piston diesel

you choose

How about a Crower 6-cycle, opposed piston hyperbar multifuel with an exhaust energy kinetic recovery system tied to the crankshafts?

[Prosorusiya]

Fairbanks-Morse used to make OP Diesel engines, which were used in submarines successfully and in railroad locomotives less so. Although the latter was mostly because they were not standard and well maintained examples still run in some parts of the world.

[The Akasha Colony]

Fairbanks-Morse used to make OP Diesel engines, which were used in submarines successfully and in railroad locomotives less so. Although the latter was mostly because they were not standard and well maintained examples still run in some parts of the world.

The Fairbanks Morse engines stuck around because EMD's pancake engines had huge reliability problems whereas the Fairbanks Morse 38 8-1/8 was reasonably reliable, readily available, and had an extensive supply chain and pool of skilled mechanics in service. By that time, nuclear propulsion was taking over and the 38 8-1/8 was good enough to work as a backup.

[Prosorusiya]

One of Sprey's arguments is that smaller aircraft have a lower RCS, and this outweighs the beefier radars available to heavy fighters. Does this argument have any stock?

Not enough to matter. RCS is only loosely correlated with size. It's usually more a factor of whether any real attention was paid to RCS and how much effort was put into reducing it. F-22 is much bigger than F-35 but has an RCS that's estimated to be ~10 times smaller. Super Hornet has a smaller RCS than Hornet despite being larger.

There was a case to be made of light fighters when Pierre Sprey was pushing them hard in the 1970s and early 1980s. At the time, rules of engagement required positive visual identification of targets before engagement and thus severely hampered the effectiveness of any BVR missiles available at the time, which also tended to have a relatively high failure rate. Thus, you had scenarios like the ACEVAL/AIMVAL trials in the 1970s where light F-5s were able to regularly close in to IR SRAAM range with heavy F-14s and F-15s, who were not able to get reliable positive VID at ranges beyond 8 miles or so. Thus, a light fighter like F-5 had a decent chance of getting into close range, firing off their AIM-9s at the heavy fighters, and then retreating. Or getting shot down but taking several very expensive heavy fighters with it. It still didn't solve the range issues, but it made the F-5 a surprisingly deadly adversary (oddly enough, the F-14 and F-15 supposedly had better performance in gunfights than the F-5, but this only mattered if they could get through the wave of Sidewinders fired by the F-5s).

But with the development of more advanced and more reliable NCTR techniques, the need for VID was eventually phased out. In Desert Storm, coalition aircraft did not require VIDs despite operating in perhaps the most complicated environment (most of the aircraft in the area were friendly coalition aircraft so the risk of friendly fire was high and the Iraqis were flying some of the same aircraft as the French). New BVR weapons like AIM-120 replaced the less capable AIM-7 and BVR went from being something of an infrequent occurrence to being fairly common. In this method of combat, radar range, flight range, payload capacity, stealth, and speed are king. Coincidentally, this is what all fifth generation fighters (the first generation designed with these advances) have been focused on: extremely powerful engines, long-range sensors (radar, IRST, passive detection), aerodynamically efficient airframes, and stealth. Weapons capacity sort of got the shaft in favor of the stealth and aerodynamic benefits of internal carriage, but that was unavoidable.

What's with the boners for "carriers are obsolete because of crappy ballistic missiles" thing these days... *sigh*

It's not just blogs and publications that are talking about it. There's real concern on the part of the US Navy about long-range anti-ship weaponry, especially ballistic missiles. While to some extent I think the "A2/AD" meme has been overplayed (most of the elements of the "A2/AD threat" are not new), it cannot be simply brushed aside and ignored. It's a challenge the USN hasn't had to seriously face in nearly 30 years: the prospect of a near-peer opponent employing technologically sophisticated weapons in large numbers.

AShBMs might not be the magical wonder-weapon that some claim them to be, but even if not, they're a weapon the US Navy currently doesn't have a good answer to. And that's a concern.

Or the concept of interdicting the kill chain. Or general countermeasures. Or that shooting ballistic missiles in a major war is asking for massive trouble when there's people who have to wary of potential nuclear weapon use.

They're not totally wrong though. Carriers aren't necessarily obsolete but anti-ship ballistic missiles and by extension the general category of long-range (1,000+ km) stand-off anti-ship weapons is a cause for concern. Mostly because while interdicting the kill chain is cool and all, you are at best just buying time and hoping the enemy doesn't manage to sneak a ship or drone or MPA close enough to guide a strike in. All the enemy needs is a single successful strike to put that carrier out of action. And it means the carrier will have to devote so much of its air wing and escort group to protecting itself that it may not have enough resources left over to launch offensive strikes, meaning that it's essentially neutralized anyway.

The preferred option of course is to outright destroy the launchers, but the problem with long-range anti-ship weapons is that they can be based well inland, protected by air bases stocked with fighters and a robust air defense network. The range alone poses a formidable challenge.

So basically, ballistic AshMs work a lot like old costal forts & fleets in being: they are just enough of a threat to force the enemy to take countermeasures, or withdraw beyond their effective range, and thereby hamper their operational effectiveness?

On the topic of light fighters, I've been personally interested in this myself, as I run a small Soviet style nation and have been working lately to copy their military a little more historically accurately, which means reducing my air defenses somewhat... and I am mulling replacing my MiG-23P interceptors with L-39ZA's, as this would reduce the maintenance and training costs resulting from operating two types, one more much more complex than the other, and be closer to the historical Chechen AF which operated L-39C's. Idk how much interceptions my AF would really need to do, compared to ground attack against ISIS and other terrorist groups in the region, and any A2A work they do on a practical level would be mainly air policing work. I am mulling going back to operating Sa-2's as well, the only reason I dropped the batteries from my ORBAT were there was shaky evidence they were still in place In the 1990's. Thoughts?

[Prosorusiya]

Fairbanks-Morse used to make OP Diesel engines, which were used in submarines successfully and in railroad locomotives less so. Although the latter was mostly because they were not standard and well maintained examples still run in some parts of the world.

The Fairbanks Morse engines stuck around because EMD's pancake engines had huge reliability problems whereas the Fairbanks Morse 38 8-1/8 was reasonably reliable, readily available, and had an extensive supply chain and pool of skilled mechanics in service. By that time, nuclear propulsion was taking over and the 38 8-1/8 was good enough to work as a backup.

Good to know... in the railroad end of applications the EMD locomotives were standard though and one out mainly because of this and not as I understand any defect in either companies design. In fact FM's Trainmaster diesels were the one most powerful of their day. And the EMD 567 is renowned for its reliability. One of the users of FM locos, the Southern Pacific is rumored to have done well with them because they had a lot of ex-Navy men in their maintenance department, an artifact of being near San Francisco.

It was the same story with ALCO's, though to a lesser extent as their 244 engine had a lot of bugs to be worked out but was rushed into production to compete with EMD. Their 251 is a great engine though, I think the Navy still uses some in their ships?

[The Akasha Colony]

So basically, ballistic AshMs work a lot like old costal forts & fleets in being: they are just enough of a threat to force the enemy to take countermeasures, or withdraw beyond their effective range, and thereby hamper their operational effectiveness?

Existing land-mobile truck-mounted AShMs like Exocet already did this. The British certainly learned this in the Falklands when Glamorgan was struck by a truck-launched Exocet that had been modified for land-based launch. But this threat has already largely been answered in the form of EW suites, decoy/chaff/flare launchers, CIWS, and conventional tiered air defenses.

China's AShBMs are the next step because while there are nowadays lots of countermeasures to regular AShMs, there are far fewer countermeasures against ballistic missiles. A ballistic missile bypasses all of the previous defense mechanisms against cruise missile strikes and requires a whole new suite of defenses to counter.

On the topic of light fighters, I've been personally interested in this myself, as I run a small Soviet style nation and have been working lately to copy their military a little more historically accurately, which means reducing my air defenses somewhat... and I am mulling replacing my MiG-23P interceptors with L-39ZA's, as this would reduce the maintenance and training costs resulting from operating two types, one more much more complex than the other, and be closer to the historical Chechen AF which operated L-39C's. Idk how much interceptions my AF would really need to do, compared to ground attack against ISIS and other terrorist groups in the region, and any A2A work they do on a practical level would be mainly air policing work. I am mulling going back to operating Sa-2's as well, the only reason I dropped the batteries from my ORBAT were there was shaky evidence they were still in place In the 1990's. Thoughts?

If you're confident you won't need any real air-to-air combat capability, L-39 is fine. L-39's air-to-air capability though is probably in the same general class as other ground attack aircraft like A-10 though. Which again is probably fine if you don't expect to ever be seriously challenging "real" fighters.

[North Arkana]

So how much of a counter AShBMs would systems like https://en.wikipedia.org/wiki/RATTLRS in a deployable form be?

[Austrasien]

So how much of a counter AShBMs would systems like https://en.wikipedia.org/wiki/RATTLRS in a deployable form be?

None at all. Missiles on the shore (ballistic or cruise) probably will not be found until they fire.

This:

(It would be somewhat larger than the Polaris missile)

And something like this:


Are what you want. It is not impossible to create a defence. But it cannot be done in the constraints of what the USN has now, a true BMD fleet defense ship simply does not exist even in concept form (though it would be surprising if someone, sometime studied the possibility on paper).

[Gallia-]

CG(X) :^)

[Seryu]

Not sure if this is the right place but I'm doing an II RP very soon and looking for some last few things to read...
1: Anyone have resources on how an asymmetrical rebel force would typically be organized?
2: Any tips on RPing a very large but low tech military that's behind everyone else on the technological level?

[Kouralia]

Not sure if this is the right place but I'm doing an II RP very soon and looking for some last few things to read...
1: Anyone have resources on how an asymmetrical rebel force would typically be organized?
2: Any tips on RPing a very large but low tech military that's behind everyone else on the technological level?

I have nothing for No.2, but for No.1, here's Allanea's Guerrilla Warfare - A Primer for Nationstates Players.

[Seryu]

Not sure if this is the right place but I'm doing an II RP very soon and looking for some last few things to read...
1: Anyone have resources on how an asymmetrical rebel force would typically be organized?
2: Any tips on RPing a very large but low tech military that's behind everyone else on the technological level?

I have nothing for No.2, but for No.1, here's Allanea's Guerrilla Warfare - A Primer for Nationstates Players.

Thanks! That's pretty much exactly what I'm looking for since I haven't ran that type of army before.

[Prosorusiya]

So basically, ballistic AshMs work a lot like old costal forts & fleets in being: they are just enough of a threat to force the enemy to take countermeasures, or withdraw beyond their effective range, and thereby hamper their operational effectiveness?

Existing land-mobile truck-mounted AShMs like Exocet already did this. The British certainly learned this in the Falklands when Glamorgan was struck by a truck-launched Exocet that had been modified for land-based launch. But this threat has already largely been answered in the form of EW suites, decoy/chaff/flare launchers, CIWS, and conventional tiered air defenses.

China's AShBMs are the next step because while there are nowadays lots of countermeasures to regular AShMs, there are far fewer countermeasures against ballistic missiles. A ballistic missile bypasses all of the previous defense mechanisms against cruise missile strikes and requires a whole new suite of defenses to counter.

On the topic of light fighters, I've been personally interested in this myself, as I run a small Soviet style nation and have been working lately to copy their military a little more historically accurately, which means reducing my air defenses somewhat... and I am mulling replacing my MiG-23P interceptors with L-39ZA's, as this would reduce the maintenance and training costs resulting from operating two types, one more much more complex than the other, and be closer to the historical Chechen AF which operated L-39C's. Idk how much interceptions my AF would really need to do, compared to ground attack against ISIS and other terrorist groups in the region, and any A2A work they do on a practical level would be mainly air policing work. I am mulling going back to operating Sa-2's as well, the only reason I dropped the batteries from my ORBAT were there was shaky evidence they were still in place In the 1990's. Thoughts?

If you're confident you won't need any real air-to-air combat capability, L-39 is fine. L-39's air-to-air capability though is probably in the same general class as other ground attack aircraft like A-10 though. Which again is probably fine if you don't expect to ever be seriously challenging "real" fighters.

Not 100% confident I wont need air to air combat, it depend on how likely one thinks that an air war with Turkey is, and how likely allied nations/other Soviet units are likely to help me. Personally I think the greatest threat might be from cruise missiles, I was hoping conventional AA and heavy mountain terrain could work in concert to reduce that threat though. Equally, I am hoping that maybe the SA-2s can take over some of the medium-high altitude defense roles... could an L-39ZA do something like intercept a commercial jet? A high jacked airline is probably a more likely threat in their air policing role than Turks in F-16s...

Also, is the airbase at Mozdok big enough to turn into a combined aircraft storage & museum facility? I am thinking of mothballing my MiGs so that if I ever did really need them again I could break them out of storage...

[Laywenrania]

could an L-39ZA do something like intercept a commercial jet? A high jacked airline is probably a more likely threat in their air policing role than Turks in F-16s...

The L-39s maximum speed is lower then the cruise speed of most commercial jets.

[Prosorusiya]

Damn it's that slow? Huh... maybe I'll rethink getting rid of the MiGs then.

[Laywenrania]

Damn it's that slow? Huh... maybe I'll rethink getting rid of the MiGs then.

755 km/h at 5km

[Neo-Pontic Empire]

2: Any tips on RPing a very large but low tech military that's behind everyone else on the technological level?

How low tech and what's the county like overall? I mean are we talking second rate military equipment like T-72s or are we talking WW2 equipment, some RPG-7s, and whatever guns they can scrounge up?

[North Arkana]

2: Any tips on RPing a very large but low tech military that's behind everyone else on the technological level?

How low tech and what's the county like overall? I mean are we talking second rate military equipment like T-72s or are we talking WW2 equipment, some RPG-7s, and whatever guns they can scrounge up?

So like... Serbia level vs Central African Republic level

[Atomic Utopia]

So I was thinking of machine learning applications in warfare, and was thinking of anti missile defense systems and realized that the problem of jamming via flares, etc. is basically the same as the problem of picking out a face from a crowd. So with that in mind, would it be practical to train a neural network to conduct target recognition for a heat seeking or radar guided missile to allow it to identify the difference between flares, chaff, et cetera, and the target craft?

Also: Using ensemble learning to weed out enemy guerrillas from online searches, posts on various websites, etc. Y/Y?

[The Akasha Colony]

So I was thinking of machine learning applications in warfare, and was thinking of anti missile defense systems and realized that the problem of jamming via flares, etc. is basically the same as the problem of picking out a face from a crowd. So with that in mind, would it be practical to train a neural network to conduct target recognition for a heat seeking or radar guided missile to allow it to identify the difference between flares, chaff, et cetera, and the target craft?

Imaging infared seekers can already screen out flares and more advanced radar seekers can already screen out chaff. You don't need a neural network for that. That's why there's so much interest in directed IR countermeasures to outright blind IR sensors using lasers and expendable radar decoys like BriteCloud that can actively mimic a fighter's radar signature rather than just using a large cloud of chaff.

The other problem is that onboard processors in missiles and other guided weapons tend to be very low-power and relatively simple, by design.

[Austrasien]

The number and types of algorithms used for target recognition, counter-countermeasure, clutter suppression and the like is already very, very large. It is a field unto itself.

Guided weapons though generally do not learn. They usually have very short operating lives, and because the current paradigm is "wooden" rounds or as close to it as possible, generally do not receive any new data after being manufactured. Even if machine learning is employed it would be in R&D to develop or refine algorithms for this or that purpose that would be inserted into the weapon in a fixed form. When a missile is fired in combat it must work, there is no longer any opportunity to refine its behavior.

In other applications learning techniques can be relevant to use in the field though. Very high end ECM/ECCM systems such as those that might be found on major surface combatants can periodically survey the electromagnetic environment and adjust their own parameters according to the desired effect. A jammer might track the angle of arrival of a cruise missiles radar seeker emissions well attempting to achieve angle deception and if the missile is not being moved off course as expected adjust the parameters of jammer (within defined limits of course) until it achieves success. Or a radio network link might monitor the frequency sweeps of hostile jammers and adjust its own frequency hopping patterns to try and minimize their effects on it. But in really high value applications like warship self protection or operational/strategic C2 networks the inevitably high cost/complexity is justifiable.

[Seryu]

2: Any tips on RPing a very large but low tech military that's behind everyone else on the technological level?

How low tech and what's the county like overall? I mean are we talking second rate military equipment like T-72s or are we talking WW2 equipment, some RPG-7s, and whatever guns they can scrounge up?

I'm thinking Cold War era stuff and newer production models that have shoddy engineering, and wondering how much of a role that typically plays in tactics. ICly Seryu has a very large military but poor engineering, especially in the Navy.

[New Vaduz]

What can anyone tell me about the GAZ-50 wheeled APC? There is one sitting in Kubinka right now but scarce information is available on what exactly it was designed for or how it came to be.