space battles in more realistic physics
don't expect me to aim too high,,, because physics isn't exactly my ball game.
assume that orbital mechanics is just another discussion,,, but it should matter because objects will probably never be just outside of some kind of orbit,, basically all combat will involve orbital mechanics.
anyway, where are these discussions??
-battles in space using bullets will probably happen. but if you make a cloud of bullets flying at a target, they are going to see them, and the distance is probably more than adequate to dodge the bullets unless there is some reason the target CAN NOT change position,, maybe it's also shooting.
-missiles are different, but they will get close enough to the defender that the defender will always be able to shoot at them assuming they have the guns available,,
-this means that its' actually REALLY HARD to shoot someone in space. There's so much distance that opponents can basically always dodge somehow. One option is to get so close that they just can't dodge, but the defender should always have the advantage in this case, and should be able to make the approach unapproachable. (with bullets).
-fighters could be used for this kind of battle, because they can fly like missiles, but then shoot bullets, meaning they can very easily change vector in order to properly aim at a given target area. (here is where orbital mechanics might start to come up)
-actually, it could get really hard to "dodge" bullets , because you can't just fly back and forth, if the battleship is huge, it doesn't change vector that quickly, so if in orbit around an object, it will first need to maintain orbit,,, THEN it will need to dodge multiple clouds of bullets travelling in from different directions, and occupying space such that certain "new orbits" might not be available.
If objects are small, like the moons of Jupiter, orbits could REALLY get wacky, and you MIGHT have to be concerned about shooting yourself!
Hi tsmspace, very interesting subject indeed!
where are these discussions??
Well it's well hidden but there's one here 🙂
(please see question from Pinback and following answer, 2nd and 3rd post respectively)
But to sum my take on the problem (supposing symmetrical engagements) :
- ships would not escape detection whenever a line of sight exists because of their huge internal power levels,
- maximum accelerations would not exceed 0.5 G. That is unguided munitions may be easily dodged at long range, until they cannot and then it's a case of mutual assured destruction (targeting would be computerized of course),
- lasers cannot be dodged but due to diffraction they would lose efficiency at long range, resulting in similar stalemates,
So my bet would be on missiles that would quietly coast on their own interception orbit and activate when close enough to accelerate for the kill, preferably multiple ones as a swarm to overwhelm the target's point defenses.
well, I agree, detection is probably guaranteed, but I can't imagine what sort of tech there will be, so I will probably ignore the ideas of detection and assume everyone definately sees everyone. An exception is in cities, like the police tracking someone, and then everything is so different because basically I'm talking about military's that are engaging far away from cities,,,
I'm basically assuming that lasers won't be a special weapon at all,,, and then there will only be lasers. They will be used for detection and ranging, but I honestly don't think they'll beat bullets before huge ships with weapons exist. People will use them but they'll be weird, and as soon as someone can get a ton of bullets it will be much more effective, and lasers will be abandoned. and then on that note, I'm assuming they will basically work exactly the same as bullets. (but you won't be able to orbit volleys around moons)
my bet is actually that there won't BE battlefields,,, there will only be missiles. Someone will have absolute control over an area, and that will be that,,, and if someone else wants to fight, they'll just shoot land-based targets with missiles that can come from as far away as they need to. There won't be any pilots anywhere. There won't be any battleships, just missiles from manufacturing centers, and missiles to counter them.
during peacetime there might be the need to put smaller missiles closer to the diplomatic opponent,,, so satellites with salvos loaded,, but they will never shoot, and once they do they won't replace those missiles, because they will need to be shooting constantly and missiles will roll off the line and be fired from there.
Sorry I was really thinking about a game here, not reality.
In that context even with a more realistic setting there are always some "future tech" aspects of the physics that may be tuned to achieve the desired gameplay properties! 🙂 Then the issue is to try and remain consistent with the chosen "rules of the game".
So about bullets: since ships would need to resist small orbital debris and meteoroids then bullets might not be powerful enough. A typical gun has an exit velocity around 1 km/s and in comparison Low-Earth Orbit is about 8 km/s. So you may have to consider "shells" instead, and preferably with high relative velocities and then invoke "railguns" for instance.
Missiles may be fired from very far for sure (coasting on an orbit leading to their target) and space regions may certainly be 'controlled' with constellations of missile launching platforms for instance. But then such systems would be very extensive and costly. And so depending on the games settings again, not every location may be able to afford them. In that case it's the depicted economics and politics that may offer alternative strategies!
Another thing I forget to think about is Electronic Warfare,, basically jamming, which might get pretty sophisticated,,, maybe even all the way to where ships require electro-mechanical (non-computerized) control interfaces to even expect to work, and where the only shots that hit are fired from point blank range from very basic weaponry.
I envision an X-wing to have literally 4 thrusters anyway, no small thrusters of any kind. It would have huge rear-facing engines that gimbal using powerful electrical synchro-servo systems that completely lack electronic components. That's why the targeting computer looks like a monkey built it. There just aren't that many systems on the X-wing, because there's no way it's worth toting around so much weight that will never work, and is just a fire hazard. A light literally has to be that big to be durable enough to handle the electromagnetic environment battleships produce during combat.
Meaning basically that Star-Wars broadside battles fought by manned gun emplacements might make more sense than people generally like to say. There might not be a computer anywhere that can be relied upon for any battle that would be important enough to make the films.
I do concur that Electronic Warfare should be a major component of orbital battles! However I would not expect jammers to be able to disrupt control systems:
# such vital circuits are always EM shielded and in a near sci-fi context one may easily invoke fiber optics links and processors for even better resilience,
# the incident power per unit area at the target goes in 1 / [distance squared] and so decays very fast (that said at close range even existing real life radars can be deadly microwave ovens).
About space fighters' physics it's possible to evaluate a set of initial assumptions using only a few simple relations:
# acceleration = thrust / mass
# thrust = [propellant flow] * [propellant exhaust velocity]
# engine power > (1/2) * [propellant flow] * [propellant exhaust velocity]²
So let's suppose that an X-Wing is equivalent to a F16 and thus weights 8 tons, of which half is propellant mass = 4000 kg. It should be nimble enough and accelerate around 1 G = 10 m/s² for say half an hour at constant thrust. So let's go for 0.75 G = 7.5 m/s² with the tanks full (and consequently 1.5 G at bingo fuel). This gives:
thrust = mass * acceleration = 8000 * 7.5 = 60 kN
The 4000 kg of propellant are exhausted over 30 min ~ 2000 s so the flow is 4000 / 2000 = 2 kg/s.
This yields a propellant exhaust velocity of 60 kN / 2 kg/s = 30 km/s,
and an engine power larger than (1/2) * 2 kg/s * (30 km/s)² = 900 MW
That is such a design supposes that the equivalent of a nuclear reactor from a real-life power plant can be fitted into a X-Wing and weight less than 4 tons.
Incidentally I've supposed even worse for my ship: 50 GW in 100 tons, based on a fusion reactor (besides a more "realistic" yield the difference is on the overall DeltaV budget as required by the game settings).
Ok,,, first on overloading the circuits,,, maybe the fighters would be targeted by highly focused beams of energy. This might mean that during a combat situation it is likely enough that systems might be cooked, that the fighters simply can't rely on them,,, after all their objective is to be incredibly close to the opponent.
second,,,, just some thoughts on how fighters might be used.
-if the fleets are approaching from opposite directions, fighters will probably not be used, or will probably only be used to help generate a cloud of fire and not change vector to match the opponent.
-however, as you suggested, ships are probably resistant to this tactic, and are able to intercept missile weapons at such range, and are able to dodge flak.
-instead, lets assume that by the time fighters will be used in combat,,, basically it's the only thing that's going to work. If missiles work, use that. If not, try any other alternative method of causing destruction from far away. If nothing else is going to work,,,, THEN try to get close and shoot point-blank at any weakness that breaks the defense.
-here's how I imagine the battle (after reading your reply). The fleets are both well defended from ranged weapons. The fleets are also well shielded,, meaning lots of jamming as well. In order to enter into combat, the fleets will need to pull up alongside each-other, and deliver ordinance at ranges small enough that interception of ordinance is virtually impossible, and ordinance MUST be unaffected by electronic warfare, and MUST be able to penetrate the armor of the opponent. High energy plasma bolts are about all that's left on the list, although I personally entertain that bullets are effective at said range, bullets can be mortars in this case, or rockets.,,, I also assume these types of weapons are VERY heavy, and run out so quickly, that even though they are potentially MORE effective, there aren't any to begin with. (or there are so few, that they are not part of the strategy for full attack).
-it is assumed that both fleets are well aware of which fleet is the winner long before combat begins. There will be one fleet that is the attacker, because they will win, and one fleet that is merely hoping to make the best of the situation and lose the least.
-The aggressor will pursue the defender until they will intercept them, and only when ships are nearly flying the same direction in the same place, are fighters launched. THis means that they will inherit most of their velocity, and the changes in relative velocity will be small. Unfortunately this also probably means that once fighters are launched, the mothership can't move much, because the fighters will not be able to keep up. Basically, they will have MORE than enough fuel for a few minutes of combat, with only minimal changes in velocity. They will LOOK like they are flying back and forth if you are in one of the ships, but actually, they are barely changing velocity.
X-wings use fuel that is pumped into the ship via hose. Also, they can enter hyperspace,, which means the film assumes QUITE a lot of power available.
-anway, I'm assuming that under normal imaginable conditions, where plenty of electronics are available,,, it is VERY EASY to shoot down enemy fighters. They probably pop as fast as marines in sc2. However, if you have them in formation RIGHT when you get to a nice firing position, and everyone starts shooting at the same time, you can probably REALLY heat up an area down range. If jamming doesn't fry your electronics, the shock of blasters cooking your shields probably will. I will assume a resistor will generally look like it does from the 70's,,,, really big. Probably, in THIS imagined world, you don't get many transistors/relays to work with.
If the battle is over already, and you can't possibly win against the opponents opening salvo, you MIGHT try to suddenly close the distance between you, and throw the Empire out of formation. Under normal circumstances, against hardened veterans, you might not expect to survive longer with this tactic, instead you would lose even MORE quickly,,, but in Star Wars,,,, well,,, the empire doesn't really fight like that. They MOSTLY just show up and everyone quits fighting immediately. MOst of the fighter squadrons will be filled with rookies who honestly don't know what's going on,, they don't even realize that's the enemy the are looking at. By the time the majority of them could possibly react, the can't see where they are going, they don't know where to fly without crashing into someone, and when they shoot, friendly fire is inevitable, so they either dont' shoot, or shoot down more of their own side than the enemy. If the rebels have a well formulated plan, and know exactly where to hit, and where they are going to hit isn't prepared for this kind of sudden move,,, then the battleships can be disabled before they are able to do enough damage to still win despite the crafty move. ,,,, OR, , perhaps because rebel fighters can hyperspace on their own,, the plan is get so close that there's enough confusion that the Star Destroyers choose to wait for a shot that doesn't kill all of their own people, which buys just enough to for the rebel battelships to jump, and then whatever fighters can make it out jump out afterward.
-since this is about inertial battles,,, instead of jumping, perhaps a sudden change in velocity is executed that the opponent isn't willing to follow, since they will need to collect up their fighters first. Because the losing side is able to choose an escape velocity BEFORE the fight, and in secret, all of the fighters are able to enter the battle, cause some confusion, and then start throttling before the prospective victor is able to determine exactly where they are going and make a pursuit maneuver. If the burn is good, and the enemy fighters are flinging in all directions, then the ships should really be able to create some distance before the enemy can get organized enough to expect their weapon to be ready to fire when they manage to pursue. (so a jump is a good way to imagine it,, because it will take a whole jump to follow) ,,
Wow that's a lot to process ! 🙂
By the way your post makes me think of "The Lost Fleet" books by Jack Campbell. If you haven't read them the physics are different from what's discussed here (relativistic velocities) but the battles are just amazing!
Honestly I still can't decide about manned fighters: as you mention they would be more fragile than larger ships and so their capability to evade incoming fire would be vital. Trying to get some numbers with kinetic weapons:
# The key point is deflection since the shooter must fire at where the fighter will be when the shells reach it. That's very complex for humans but not at all for computers with the proper input data. I'll go for a assured hit if the fighter does not maneuver.
# So supposing the fighter is constantly flying an evasion pattern, with a maximum of 1 G as supposed above and with average kinetic weapons exhibiting a muzzle velocity of 1 km/s. Also let's suppose the fighter must have moved by 10 m relative to its initial trajectory (when it was fired at) for a guaranteed evasion:
On the first order the shells' flying time is then given by:
(1/2) * evadingAcceleration * t² > evasionDistance
This gives t ~ 1.4 s and thus the closest non-lethal approach distance is about 1.4 km: seems workable indeed.
But that would need a very talented pilot with a solid stomach and a streak of good luck because there's always the chance that the shooter randomly aims right. Also area flak would defeat the tactic, not mentioning that these fighters would have to be designed so as to be able to shoot at their target while flying evasion patterns.
However with lasers or masers as you suggest the "muzzle velocity" is c = 3 10^5 km/s and they would successfully hit, always :/
So maybe as you suggest with fighters able to jump, the best role would be guerilla fighting against lightly defended targets, and probably not large scale fleet to fleet battles?
About orbital tactics in general.
From what I can see playing with my flight planner one key point is the available DeltaV budget with respect to the local gravity field. That is 10 km/s is a lot of maneuvering around a tiny moon, but not that much in low-orbit around a gas giant. To put numbers on this one can consider the velocity on a circular orbit at the location: that could be 100 m/s around a small moon and 30 km/s deep in a large gravity well, to be compared to the available maneuvering DeltaV.
That is the local celestial body, initial positions and approach vectors would have a huge influence on a battle obviously, up to the possibility that the battle may actually happen or not. I would expect that a defender with enough maneuvering budget would be able to effectively refuse an engagement. But that's something I'll have to study carefully: for instance what is the best orbit altitude in a given gravity well from the orbital warfare standpoint? There is also the need to consider the aftermath of the battle: a military win with a fleet stranded on orbit would be of no use...
well, it's hard to reply in order, I will instead use bullet points to randomly reply to your comments, , these are just something I thought when reading your post, and are not organized or oriented towards a "goal".
-well, in the civil and revolutionary wars, it was better if troops DIDN'T avoid fire when preparing to fire a volley. There are some important similarities because we are still talking about bullet volleys, where accuracy is in part up to volume, and where only a shot fired by an entire firing line will have the required effect. (sure, individuals firing when ready would be impactful, but overall a single orchestrated volley does so much more,, it's something to do with with the total energy of the volley).
----so continuing about the volley, lets assume it's a concern that the shots will miss. So, in order to expect hits, the volley will need to cover a wider area, meaning not all of the volley will hit, but every volley will have something that hits. ,,, in this case, you might have ALL guns in the fleet fire down exactly the same bearing, which is determined by the commander at the time the shot will be fired. This will create a nice wide area of effect. (actually, probably depending on how far you are from the center of the firing array (not a line in 3d), you will have a slightly different bearing, similar to how ww2 fighters had their guns tuned to certain distances, .
-in this situation,,, the fighters simply DON"T maneuver, but it is assumed that their small size will already make them hard to hit. (missiles are a different story, because they are guided, but even still it might not be the winning plan for individual fighters to go flying around when everyone is in a strict formation). ,,, So for anyway one imaginable scenario, where a broadside battle is the plan, the fighters will literally launch, and fly a very limited path to their position in the formation, then literally NOT maneuver, because they should only arrive at their position immediately before the shot is to be fired, then,,, they shoot,,, and return to the mothership so that the fleet can maneuver again.
----okay, so maybe the fleet can maneuver without collecting the fighters, because they have so much more energy than we are thinking about that really it's nothing, and they can just fly around all day, and change orbits all day, and even ignore orbit altogether whenever they choose, because they will be able to accelerate all they need to once they once again settle to some normal trajectory. ,,,,
--avoiding the conflict will probably be just like fighters evading fire. There isn't avoiding conflict if your higher commanders say fight, because they will be sacrificing the fleet to accomplish another objective.
--I"m basically froze up for now.
Here's something I tend to think about a lot when it comes to games.
basically, with a goal of a very in-depth game, you have to work your way up. For many people, that means play gumball games, but for game developers, that means people will constantly want the game dumbed down. I'm guilty, because that's exactly what I spend my time doing.
I don't want orbital mechanics in a game, I can't even imagine working with that. I only recently started to be able to have 6dof games where all 6 degrees of freedom have a joystick axis assigned. (I made a game controller with 4 joysticks). I love starmade, because it's like minecraft, where everything is just blocks and basic concepts.
In the game Orbital Racer, everything is in orbit together, so there ARE no orbital mechanics. You are assumed to be able to behave as though every object you will interact with is static, and your velocity is relative with no other considerations.
In real space, however, I don't even have a starting picture of what kind of "space" you have to move around without losing control of your "orbital mechanics". How far away from the mothership can a fighter fly before the orbit of the fighter will cause a problem and result in an orbital vector that overpowers a relative velocity?? So, if I fly one direction from the mothership, I should be able to use half of my fuel, then turn around and fly back,,, assuming that there is no gravity to consider, and the mothership is not moving. In orbit, of course, the mothership is BOOKING around the planet or other body, so If I start to accelerate away from the ship in my fighter, I'm going to result in a new orbital velocity, ,,, so exactly how far can I go before I can no longer act like the ship is static and I'm just flying back and forth??
Space combat without electronic-assisted systems, and even some kind of analytic AIs, would be impossible to do for a human manually, there are too much parameters in real time to manage.
When you see modern jet fighters and all their in-systems assist to the pilot, and we only talk about conventional atmospheric combat here.
And when you see how the Apollo 13 team did navigation manually with a unstable damaged spacecraft, they had a margin of error contained on one hair, and could have died multiple times.
Anything is moving in space, and the relative speeds between two objects can be staggering (we don't talk about the ridiculous low speeds of ED/SC/Freespace and so on) in the order of km/s.
But yeah, reproducing that in a 6dof flying space game would harsh in term of gameplay, because you would need a Orbiter-like level simulation, not a arcade on passing for a "simulation" as for in ED or SC.
It's why most of the games today have a sort of hybrid system; not entirely the WW2 simplified aero model of Star Wars, but not the hardcore one provided by reality either.
@tsmspace all your questions about orbital mechanics are completely legitimate, and the answer is precisely given by @farcodev : you're not supposed to do it manually and a spaceship should come with all the necessary automation and tools.
(I've added some links to in-game videos about the flight planner and flight controller in my thread if you want to have a look - too many links however because the post is currently held for moderation but hopefully D1 or Pinback will release it soon! 🙂 )
Ok. so here's a totally different approach.
lets assume, as for militaries,,, there aren't any fighter battles. Actually, we can't even imagine what those battles would be like. Ok, in star wars, it's clearly fighters, and there's a lot of ways that can be imagined, but moving past all of that.
probably, if there are going to be fighters like that, actually, there will be a lot of space that's highly developed. There will be cities, other infrastructure, just tons of structures everywhere. There will be so much stuff, and so many people, that when it comes down to it, the "militaries" of the galaxy just don't even have battles like that.
HOwever, , there are criminals and non-citizens, and undocumented refugees, and all sorts of other people . Think blade-runner meets space-fighter game. In this situation, things will be relatively small. Actually, because of peacetime, lots of objects will be very close to eachother, so a ship flying around might actually not expect to fly very far. It won't traverse from one orbit to another, it won't go anywhere at all. It will fly past joey's house and then back to marley's. There are police, but they don't fight war with war tactics. They do little car chases, and always do whatever is possible to apprehend offenders for the purpose of discipline and the "training of citizens".
It's not about attacking a target, it's about finding a few bad eggs within a mostly well behaved urban or rural scape.
Now, there might be all kinds of weapons, but police have to always try to be non-lethal and most of the population won't have access to serious hardware. Rebellions are powered by rudimentary make-shift hardware that can be obtained despite regulations , with real weapons rarely or never making an appearance, and police are likewise equipped with exactly enough to counter this trend, so that they too do not proliferate powerful weapons that serve no other utility, and so that peaceful citizens can feel they are not being oppressed, but instead are being protected, with the goal being arrest and rehabilitation with every threat.
An empire might have absolute rule. We don't see tanks regularly cruising the streets, and we wouldn't see true Battle-star's in a governments standard fleet of ships. They might be able to function as battle-cruisers when the opponent is rag-tag renegades with no particularly powerful weapons, but were there to be a true threat to such an Empire, completely new fleets would be required, with more destructive power and resilience.
So, a TIE fighter is mostly an antennae for long distance arrays, and is manned because the pilot can do so many other tasks via internet while in the ship, it's worth the benefits of someone being there. Sure, for battle, they have to use the same ships, but there wasn't going to be a battle, and everyone voted to make ships that wouldn't be good at battle. They wanted Star-link. When there IS battle, it's not battle, it's a riot, and requires riot police. When the Empire kills an opponent, it's a tragedy, and would have been avoided if at all possible, however it is unfortunate that the cost of interrupted infrastructure can be more deadly than killing a few rioters in order to return the infrastructure to working order. Better to choose to kill one than let millions die.
At this point, ships will much more frequently be one fighter vs. one fighter. There will be very small distances, so fuel is not a concern. There are no orbital mechanics, as long as you stay within "bounds" of the city limits, and don't go faster than allows you to turn around the numerous structures that make up the "city", you will never experience "orbital mechanics". THe only time such grand-scale concepts are a concern, are when transporting goods from settlement to settlement, or for "construction" projects. for an individual pilot, there are only a few people they are looking out for, when they see them, they will try to shoot them with humble sorts of guns they can get away with having (police turn a blind eye), and encountering a major combatant like a battle-fleet means run and hide until the whole thing blows over.
As for how the battles went leading up to such massive infrastructure and population,,, well, you're right. It's hard. basically there were no iffy battles. Either one side showed up and the other surrendered immediately, because there was not going to be "fighting" , only pigeon shooting, or a little bit of pigeon shooting took place, THEN there was a surrender. (The US doesn't go around fighting the militaries of little countries. If there was really going to be a conflict, US troops stand back, bombs kill some people, then everyone else gives up. )
There would be people STUDYING how to inflict damage on objects in orbit, but there wouldn't really be pitched space battles. Someone would be so far ahead that if there was going to be a fight, they would just take things out until no one wanted to fight anymore. Every shot fired by the winner would hit perfectly, and every shot fired by the loser would be defeated perfectly. The winner would take zero casualties, and the loser would only take casualties if they continued to be aggressive even after their robotic equipment had been destroyed/disabled, but because it would be clear they are utterly defeated they would probably choose to surrender.
Therefore space battles would go exactly like every video game. You choose a loadout (because you have no idea what you are really doing), you go out, find a place to start shooting, and most likely die immediately!
@tsmspace I definitely agree with you about peacetime. The more realistic the physics the more resourceful a spacefaring civilization must be to even exist, and this means peace obviously. IMO this is also tightly linked to "deterrence" indeed: space structures are so exposed and costly that large scale orbital warfare would just be out of the question. Incidentally in my sim I've chosen a "Space Guard" setting instead of a "Space Navy" one for these very reasons.
Your concept of extended orbital cities is very interesting 🙂
IMHO it would have to be organized as multiple coplanar rings, alternating structures and empty lanes (= "divisions"). You're right that at small relative distances, space is nearly "flat" because all nearby orbiting bodies are submitted to the same gravity. However this is only an approximation and over time objects that are not strictly on the same orbit do drift significantly (even when neglecting all the tiny forces that affect satellites IRL). For example I did the experiment and spawned the ship 1 km above the rings of a gas giant, in "level flight": 2 hours later I was colliding. Incidentally the initial "altitude" does not change the time of the impact, only the velocity! Actually it's in close relative flight that orbital mechanics are the most counter-intuitive, to the point that to overtake an object that is in "front" of you on your orbit, the most fuel-efficient way is actually "braking" first!
That said this does not make your idea impossible at all, and these effects are still only "drift" and you're right tiny thrusters would be able to deal with them very easily.