Well, optimizing the gun for BLOS fires and maximum penetration LOS fires is different so the design have to figure out what to do. Propellant and sabot length are important factors for KE penetration, while BLOS fire favors sheer payload, more modest acceleration, variable charges, high gun elevation and so on. The maintenance of reliable non-Sabot anti-tank ammo means sabot performance is not that important unless one faces minimum range engagements.
From the perspective of upgrading existing tanks, adding sensor masts to tanks for organic turret down capability, combined with good GLATGM option does make some outdated vehicles semi-competitive, on the defense, for cheap.
The talk about LOS is describing what it is exactly I don't think is necessary to preempt counterarguments like:
Omg the APFSDS pen is terrible, this tank is a useless waste of money as "electronics thingys" are all junk if you "insert jamming/emp/lasers/smoke" and swarms of 50+ 152mm armed Armata will start 500meters from you and Zerg you do death. We need liquid propellant 183mm to provide suitable overmatch against Russian swarms across Poland!
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If one starts leaning on indirect fire anti-tank, the role gets mixed up with dedicated howitzers. The question becomes "why not just get more howitzers" and all the arguments about force structure explodes.
The thing to think about is probably whether BLOS gun tubes as a important constraint. If battle network targeting capacity constraints is smaller than fleet weapon rate of fire than adding tubes don't do much, while if the former is plentiful than adding tubes can be helpful. If we are talking about effective high volume targeting by both sides (peer-ish conflict) however, the battle evolves to a artillery duel so the tilt probably falls to more howitzers for the range.
The development of deep battles will also provoke greater defensive capability on part of artillery as they are threatened by recon-fire networks more so than before. Networked early warning, soft kill, armor and some hard kill (against loitering munition/ISR at least: formation based yes, integrated: depends) We can see convergence here.
I guess the end game differentiator will be responsiveness in close combat (things like gun stabilization/handling, organic sensors, etc) and frontal armor trading off improved gun range.
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Some ideas I'm working on:
I.
Then there is autonomous loitering munitions: just fire a swarm of them and not worry about communications as much. I guess the combine arms in this domain, is that the bandwidth and "fast, high performance weapons" get reallocated to reliable defeat of high value targets like AD radars and effective area C-RAM that can neutralize a swarm, while cheap swarms help maintain situation awareness and take out unprotected targets.
One thing that have not fully developed is aerial counter mini-UAV capability: what would it look like and how efficient and how the offense-defense co-evolution work? Prelim thinking is high performance (say fighter) aircraft packing area sensors to direct narrow sensor anti-air drones, with directed energy armed aircraft sweeping the air in more permissive environments. The question is the operating ranges and scale, the size of aircraft deem recovery worthy, and sustainment constraints. how far forward the basing, with what terrain constraints and cycle/pack up time? The answer to these questions will shape the availability of swarm to influence battle on land, and published analysis is limited.
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Some ideas I'm working on:
II.
In any case, for me what is interesting to think about is the future of maneuver as opposed to the vehicle that have a turreted gun.
Having thought about the future deep threat environment, what does the survivability onion say about threat to the "leading" land vehicle?. Note of course you'd send cheap UAV or use long range sensors to scout first.
So what would the leading vehicle face? Well anything standoff sensors can not reliably spot and clear by ranged fire must be dealt with.
1. Stealthy, underground, indoor threats from sensors, mines, tunneled forces, infantry.
2. Fast threats, approaching from outside sensing network range. Enemy ranged fire.
3. Resilient threats: hard to kill at standoff despite detection -> used to be the classical tank, What would this look like today?.
As I see it, the really stealthy threat is volume constrained and it is possible to defend via armor. Fast threats have no hard constraint but is expensive, the question is whether to go expensive and defeat them, or cheap and take attrition.
If we go by mine warfare logic, there is no detecting the threat first, only taking hits and carrying on. Perhaps trying getting the first shot against stealthy platforms is wrong. Perhaps the equation of trying to defeat missile trying to hit slow land vehicle by using projectiles capable of hitting another missile (aka hard target) is a losing proposition.
Perhaps:
1. Really cheap but armored UGVs, demand either hit to kill and/or sizeable warhead (armor can be cheap)
2, with rather poor ranged sensors (sensor arms race gets expensive) as the enemy spots you first always, just have enough (or off board support) to pick up the firing signature to shoot back. Must be able to detect stealthy threats at very short range though, if the opponent tries to hide and fight follow on forces.
3, and not very good firepower (low organic ammo/weapons performance to cut cost/internal volume/weight, provision for but generally not with, higher performance missiles). Off board things can shoot instead.
4. not sure how much mobility do I want this, maybe look at costs first
5. while operating on autonomy, poor behavior reliability means investing much into the platform is a waste anyways.
It is practically a decoy but real enough to force a real response, ranged interdiction fires have lowest effect relative effect compared to different vehicle designs.