photon

What I don't know is how far a NATO AD umbrella based in Poland and Romania could reach. I suppose the question is whether it's worth the escalatory risk to free up whatever Ukrainian AD is currently tied down in that backfield. Ok - Patriot is good to 70km so even Lviv would be a stretch, so probably not worth the escalatory risk. Sigh. Of course, it would be better to just give a more effective and larger AD umbrella to Ukraine and let them operate it where they see fit, but American policies is, as we've noted, totally dysfunctional right now.

Another question I don't know the answer to. The consensus of the Thread so far has been that a NATO imposed no-fly-zone poses unacceptable escalatory risks (because it would involve NATO assets shooting down Russian planes). Does that escalatory logic hold now that essentially all (all?) of the Russian incursions into Ukranian airspace are unamanned? Is there strategic room for a more nuanced ruleset - something like, "We, NATO, will shoot down all unmanned aerial objects that are within 10km of a large conurbation or civilian infrastructure target west of the Dniper?

World War II at sea was a race to understand a similar shift. In the span of a few years we went from measuring naval power projection in "weight of battle line broadside" to "size of modern air wing". Heavy surface ships survived inasmuch as they were able to be useful to the air wing projection assets, which was mediumly, and then not so much. That transition happened in less than a decade.

I'm convinced. Thanks! This has been really helpful to me.

You could maybe talk me into the main gun being useful for shore bombardment, but good gravy - if you're firing at hostile vessels, how many things have gone badly wrong by that point? I'm really curious when was the last time a ship fired its main gun at another ship in anger?

Thanks for explaining what I'm trying to do better than I could! What I'm trying to articulate (somewhat hamfistedly) is a tension between a hard requirement and a thing-you-appear-to-really-want in a weapon system. The hard requirement is that you must physically transport some physical object to your target to deliver whatever effect you're hoping to deliver. Mostly I'm thinking about kinetic effects, but maybe others too? The thing you want is to delay, as long as possible, the collapse of the weapon's time and space option space. For a thing like a rifle, that space collapses as soon as the bullet leaves the barrel. For an FPV drone, that targeting time and options space remains uncollapsed until either your battery runs out or you hit something. Because the energy isn't put into the weapon system all up front, you can use that energy to retain the targeting option space for much longer as the weapon moves from launch to target. I think when we talk about "precision", we're mostly talking about delaying the collapse of the targeting choice space as long as possible (which requires the weapon to retain energy as long as possible).

This seems true to me as well, and it's what I'm trying to make sense of with my time-energy curve musings.

I'd be really curious what fraction of tank kills in Ukraine are caused by what. Has that started emerging yet? It seems like tank-on-tank fights are very rare? And often at absolutely suicidal ranges where well thrown rocks and sticks would penetrate armor?

Really appreciate your comments. So, here I'm thinking about HEAT and APFSDS rounds. Their time-energy curves look really different. For APFSDS, the object that delivers the effect is the arrow, it receives all its kinetic energy as it leave the barrel. It gradually loses energy in flight - your note that much of that energy is waste energy is right on - until it transfers the kinetic energy to the armor of whatever you're shooting at. Compare that to HEAT. the object that delivers the effect is the copper liner of the shell that's (at the last possible moment) formed into a penetrator. At firing, the shell can have much less kinetic energy because it's carrying with it a reserve of chemical energy that, at the last second, gets converted into kinetic energy in forming the penetrator. So the energy for the same(ish) effect is distributed differently along the energy-time curve, and for the HEAT shell, much of the energy is provided to the actual penetrator when it is literally touching the target. Because of that, as you rightly note, you have much less waste energy, so less signature. And it's more controllable, so you can use fins and whatnot to steer it in the terminal phase (like the modern Javelin). Does that make sense? I might need to draw some of what I mean.

So, I'm genuinely curious why we still put naval guns on ships. I'd wager that there were individual minutes in some of the battles near Guadalcanal in which more shells were fired than have been fired in anger in the last fifty years. Am I wrong about that? I'll have to drag out Morison, but some of our radar equipped semi-auto six-inch cruisers fired a couple thousand shells per engagement (to the great annoyance of the fleet sustainment and logistics commands). A good thing to compare is high level bombers with dive bombers. Both had range, but the dive bombers could apply energy to the weapon (laterally) very late in the time-energy curve. It was easy to dodge the high level bombers, not so much the dive bombers. If you offered Jesse Oldendorf the choice between his battlewagons and a half dozen SeaBabys per enemy ship at Leyte, he's be crazy to pick the battlewagons. And if you offered that choice to the folks doing sustainment, they'd knock sense into anyone even considering the battlewagons. You're right about volume of fire ameliorating the bad time-energy curve of naval gunnery. Look at the price of expanding that option space through volume of fires, though: huge logistical tail, vulnerable ships (big magazines), giant shoot-me-here sign when applying fires. And we've seen the Russians go for a replay of that in the artillery fight in Ukraine with modest (?) success.

Right - so what you're doing there is reserving some energy to apply later in the time-energy curve. And as we've seen, even a small amount of reserved energy greatly improves precision and lethality.

Ok - those are all really good questions. Let me try and tackle them. 1. I have no idea. They're some sort of boundary case. But the creepy-crawly mines that @The_Capt has occasionally described seem like an attempt to save some of the time-energy curve to the last possible minute. 2. So, I'd say that what explosives to is they reserve available energy to be applied much later in the time-energy curve. With explosive weapons, the shell itself is not the thing that delivers effects, but the fragments and gasses. By retaining that energy until late, you can choose when to apply it for maximal effects. Think solid shot vs. mechanical time vs. proximity fusing for anti-aircraft guns. If you have a reserve of chemical energy to convert to kinetic, you can apply it in a much more precise and effective way. 3. Agree. My theory doesn't speak to this. 4. Agree. 5. So, a pulsed directed energy weapon would have (functionally) a zero time-energy integral, because the time to target is effectively instantaneous. If you need to hold the beam continuously, your time-energy integral will be large, you'll have a huge signature, and it's counter-fire time. It's both retaining maximum option space as long as possible, and minimizing the time-energy integral to minimize signature. The launch of a drone is a lot harder to detect than the launch of a missile, which is itself harder to detect than a 155 firing. The much larger energy spike for the 155 means the whole system has to be much larger (to contain and direct that energy). The more gradual energy spike for the missile means you can use a smaller system to launch it. The effective non-existent energy spike for the drone means the launching system is basically non-existent.

So, I'd suggest that naval artillery shells are the easiest weapon system to defend against (of those available to navies). We developed a great system for defending against them more or less as soon as they appeared: steer into the splashes. Because all of the energy is imparted to the shell at once (in the barrel), you can predict, with great certainty, where the shell will go and when it will arrive where. It's option space for where it delivers its effect totally collapses at the time of firing. You have some large number of seconds to be not-there. Now, if you're at a range where that number of seconds is way too small, you're boned. But the size of the lethality sphere for naval artillery is well understood, so don't be there. Compare that to a SeaBaby, where the travel energy is imparted very gradually. It has a much larger option space much later in its travel. That makes is much harder to avoid and so far, to interdict; Could a current generation CIWS even see a Sea Baby at the speeds it's moving? How do you separate it from the background noise?

So, I've been thinking and reading, and want to advance a thesis for folks to hammer apart. It's a combination of @The_Capt's language of option spaces with battlefield physics. Maybe this is well known, but it's new to me. Here it goes. The goal of a weapon system is to deliver kinetic energy (in the physics sense) to a particular place at a particular time. Let's gloss over how you pick that place and time (which is in its own revolution right now). You could think of each weapon system as having an energy-time curve that represents how much energy the killing bits have at a given moment. A couple of exampled: 1. A (ancient, thrown; not modern AT) javelin. The tip has very low energy until thrown. Steep curve (maybe < 1s) to get to maximum energy when just released, gradual decrease in energy as it follows a ballistic trajectory (maybe 5s), then it delivers its energy to the target. 2. A naval artillery shell. The case fragments have low energy while in magazine. Very alarmingly steep curve (< 1s) to get to very large maximum energy when exiting barrel. Gradually losing energy during long ballistic flight (30s+). Loses huge gobs of energy penetrating deck armor (< 1s). Shell explodes imparting large kinetic energy to fragments and gasses delivering energy to target. 3. An air launched cruise missile. The warhead has low energy on runway. Jet engines being to gradually impart both kinetic and gravitational potential energy (minutes to hours). The turbojet motor lights imparting a steady stream of kinetic energy as the missile travels (minutes to hours). The warhead explodes imparting large kinetic energy to fragments and gasses delivering energy to the target. 4. A grenade dropping drone. The drone takes off using the minimal energy necessary. It cruises to the target area using the minimal energy necessary for level flight. Grenade falls, explodes imparting kinetic energy to fragments and gasses delivering energy to the target. Here's my thesis: the flatter the energy-time curve (i.e. the slower its area integral grows), the larger the option space for the weapon, and consequently the harder it is to defend against the weapon. Additionally, the flatter the energy-time curve, the smaller the signature of the weapon system, and the less it attracts counter fires. I think we're seeing this dynamic in all theaters and modes of warfare in Ukraine, and the Ukrainians are putting on a master class in developing weapon systems that retain maximal option space for as long as possible. It's just precision that is changing the battlefield dynamic, it's weapons that retain their option spaces much longer than even a decade ago.

This is such a weird take to me as to be somewhat incomprehensible. Like, we seem to be operating in different factual universes. Italians bogged down in Albania? How is that an apt comparison? What particular weapons systems are we depleting the reserves of? We've been culpably stingy with our second and third tier weapon systems. Your points contradicts one another. If China is learning to fight a western military that doesn't use any of its airforce, any of its modern deep strike capability, any of its naval capability, any of its modernized mech force... learn on, I guess? On the contrary, everyone is learning that the shape of the battlefield has changed, and changed in ways that seriously favor the defender. The PLAN has to be looking at the videos of the SeaBaby double taps and thinking hard about what their losses crossing the Taiwan strait would look like. Everybody is looking at the rise of low-energy precision fires and wondering how totally that's broken mechanized mass. Everybody is looking at the totally illuminated battlefield and wondering how complete their ground-to-space ISR system is.