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Defense of a Solar System

I'm curious if anyone else might be familiar with a game that covers a whole solar system that allows you to maneuver fleets/squadrons around and resolve conflicts on a tactical(?) scale?

This is STARFIREs bread and butter. It handles intra system, inter system, and tactical level maneuver, with combat only at the tactical level. It even has rules on when to bump the strategic level ship movement during a tactical engagement. For example, say you had 2 fleet elements, in adjacent system hexes. One of them engages an enemy element and you drop in to tactical combat. Some number of tactical turns later (50? 100? not really germane here), the system level ships move, so the fleet element in the adjacent system hex can now move and join the tactical game.
 
This is STARFIREs bread and butter. It handles intra system, inter system, and tactical level maneuver, with combat only at the tactical level. It even has rules on when to bump the strategic level ship movement during a tactical engagement. For example, say you had 2 fleet elements, in adjacent system hexes. One of them engages an enemy element and you drop in to tactical combat. Some number of tactical turns later (50? 100? not really germane here), the system level ships move, so the fleet element in the adjacent system hex can now move and join the tactical game.

Starfire works on that level because of several factors...
... the most important being constant speed drives, rather than acceleration drives.
Based upon 3rd ed...
Tactical is 30sec turns, 1/2LS hexes
Interception is 30 minutes, and 30ls hexes
 
In atmosphere, a large nuc explosion within 1km would blow all but the largest ships like a leaf in a hurricane. Assume crew as now being scrambled eggs...

That's why I believe killer missile batteries deep in GG (used as minefileds) could have devastating effects in refuelling fleets, and probably be quite hard to detect

Starfire works on that level because of several factors...
... the most important being constant speed drives, rather than acceleration drives.
Based upon 3rd ed...
Tactical is 30sec turns, 1/2LS hexes
Interception is 30 minutes, and 30ls hexes

And deep space minefields have a great strategic importance in the system defense in Starfire.

Anyway, in Starfire the system defense strategy is very different than in Traveller due to the fact that the entry points to a system are fixed, and usually only a few of them per system (2-3 being the usual, IIRC). The way it treats alertness to unexpected arrival of a fleet is nice, though...
 
Hi,

I had forgotten about Starfire, but probably for the reasons Aramis suggests, back when I had played it at school I never really got the feeling that I was playing in a solar system with orbits and such, but rather here was a map with some stuff scattered about.

I guess that maybe because travel times in system can be so high in Traveler, and during different times of the year, the different orbits of the planets can result in fairly high differences in relative distance between them, I'd guess that a solar system based game for Traveler might have a fair bit different feel to it.

I really did enjoy playing Starfire though when I was young, and I might just try and dig through my stuff to see if I still have a copy of it. Thanks for the suggestion.
 
Starfire (and Imperial Starfire) is a good game, with a sound system to incorporate strategic, operational and tactic space combat. Only dirtside combat was quite faulty (just because too abstract).

But that doesn't mean anything of it might be extrapolated to Traveller, as the standards and assumptions (sci-fi basis, etc) are just too different.
 
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Hi,

I recently picked up a copy of "Orbital", which is a Traveller compatible sourcebook for early space-fairing era adventuring our Solar System. In this book it has a simple map for the inner solar system where space is broken into segments along the orbital arcs of the planets (which I believe is actually similar to the map in The Air Eaters Strike Back, which I may have inadvertently said was a hexmap in an earlier post).

Anyway, I may try and see if something similar might work for use in the Traveller OTU. One big concern though would be how to handle elliptical orbits and such.
 
Reading this discussion, I'm reminded of two starship classes from canon, the Type 'S' Scout, and the Tigress class battleship.

The Type S would make the ideal defensive sensor platform operating in one of two modes. The first mode would be lurking near possible refueling spots (and/or other strategically important locations) within 1 light week of a system's main world. Upon detecting a jump transition, they would begin recording sensor data and transmit it to the main world. Being so much closer than platforms orbiting the main world they would be able to gather more detailed sensor data and, possessing a jump drive, could easily micro jump to safety before the enemy could engage.

The second mode would require a much larger number of scouts and would likely only be used for major systems. Basically they would provide a shell at around a 2 light week radius from the main world with about a light week separation between each scout. This early warning sensor array would pick up enemy activity and relay sensor readings via micro jump, at effectively transluminal transmission speeds. Given enough scouts perhaps two shells, an inner and outer, could be deployed. Due to the bypassing of normal transmission delays via the use of a micro jump, enemy ships would not be able to mount an 'observe then micro jump to raid by surprise' operation.

Against secondary targets, a single large ship could jump in system, observe and possibly refuel, then micro jump to attack by surprise - or pass on by. This possibility implies that if a system defenses cannot defeat the largest enemy ship capable of raiding solo when caught at the disadvantage of surprise, the defenses might as well be stripped down to be merely enough to discourage piracy and redeployed to reinforce a more important potential target.

The Tigress class comes to mind because of the time delays possible in fleet jump operations. Against secondary targets, a single large ship could jump in system, observe and possibly refuel, then micro jump to attack by surprise - or pass on by. This possibility implies that if a system defenses cannot defeat the largest enemy ship capable of raiding solo when caught at the disadvantage of surprise, the defenses might as well be stripped down to be merely enough to discourage piracy and redeployed to reinforce a more important potential target.

Numerous variations on the raid theme are possible, including skipping the observation step - the main ship jumps straight to the attack while the supporting fleet jumps in and refuels would be one slightly riskier possibility.

PS: Regarding some other threads concerning canon ship designs, a few of them at least make sense even by High Guard rules when you consider operations such as this.
 
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Against secondary targets, a single large ship could jump in system, observe and possibly refuel, then micro jump to attack by surprise - or pass on by. This possibility implies that if a system defenses cannot defeat the largest enemy ship capable of raiding solo when caught at the disadvantage of surprise, the defenses might as well be stripped down to be merely enough to discourage piracy and redeployed to reinforce a more important potential target.

This changes if one can tell where a ship is jumping to, then they know it will be an insystem jump.

Otherwise, yes, I have come to the same conclusion. I think, if gas giants are few, then they would be fortified to prevent the refueling of enemy fleets; however, conversely, this also provides impetus for an "offensive defense" strategy, where a polity would attack threats. Even mild fortification of systems, given their volume and the extent of the fortification (giant monitors and mine fields) needed to contest a system with an enemy fleet will strip power from offensive fleets.
 
Reading this discussion, I'm reminded of two starship classes from canon, the Type 'S' Scout, and the Tigress class battleship.

The Type S would make the ideal defensive sensor platform operating in one of two modes. The first mode would be lurking near possible refueling spots (and/or other strategically important locations) within 1 light week of a system's main world. Upon detecting a jump transition, they would begin recording sensor data and transmit it to the main world. Being so much closer than platforms orbiting the main world they would be able to gather more detailed sensor data and, possessing a jump drive, could easily micro jump to safety before the enemy could engage.

The second mode would require a much larger number of scouts and would likely only be used for major systems. Basically they would provide a shell at around a 2 light week radius from the main world with about a light week separation between each scout. This early warning sensor array would pick up enemy activity and relay sensor readings via micro jump, at effectively transluminal transmission speeds. Given enough scouts perhaps two shells, an inner and outer, could be deployed. Due to the bypassing of normal transmission delays via the use of a micro jump, enemy ships would not be able to mount an 'observe then micro jump to raid by surprise' operation.

The possibility to flight from confrontation with a microjump is an interesting one, but I'd prefer to make the pickets with somewhat larger ships, so that they could confront scouts or corsairs (let's say a type T patrol cruiser or even an armed free trader), depending of course on budget and perceived threats.

The Tigress class comes to mind because of the time delays possible in fleet jump operations. Against secondary targets, a single large ship could jump in system, observe and possibly refuel, then micro jump to attack by surprise - or pass on by. This possibility implies that if a system defenses cannot defeat the largest enemy ship capable of raiding solo when caught at the disadvantage of surprise, the defenses might as well be stripped down to be merely enough to discourage piracy and redeployed to reinforce a more important potential target.

Numerous variations on the raid theme are possible, including skipping the observation step - the main ship jumps straight to the attack while the supporting fleet jumps in and refuels would be one slightly riskier possibility.

PS: Regarding some other threads concerning canon ship designs, a few of them at least make sense even by High Guard rules when you consider operations such as this.

As always, it depends on many factors. One of them is that the information this raider in force receives will be somewhat old (depending on the distance the GG is), and it may even change in the time it makes the microjump, but this problem will exist in any naval operation in Traveller.

Another problem is that the Tigris is not streamlined, so depends on smaller crafts to refuel, and the operation is quite lengthy, so giving the defenders time to react.

From the POW of the defenders, its DSBs might well be hiden landed on planets (or asteroids), so giving a false intelligence to the incoming ship until too late. The same appearence of such a ship will be enough to raise the alertness for some weeks, until sure it has not microjumped to the main planet (or other valuable target). On days 6-8 since jump, defenses will be fully alerted just for this case, even if no possibility to tell about the jump destination exists.

As for scouting, I'd use ships with 2 jumps fuel capacity and unarmed (or at most very lightly so, as to avoid its crew to become mavericks) and jump in the middle of nowhere (in the vacuum between two orbits) just to avoid the jump exit point being defended. From there the ship would make its scanning and jump back to rejoin the main fleet with the reports.
 
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Let's all read that passage as it's vitally important that we're all on the same page.

Regency Sourcebook, page 79, Penetration entry, second paragraph:

Penetration is accompanied by gravitic "indentation" and "ripples" which can be detected by sensors with a hard fire control lock on the departing ship. Proper analysis of the penetration angle, jump envelope configuration, and entry vector can allow a prediction of the likely direction and distance of the jump. Prevention of such lock-ons is one of the main missions of rear-guard screening forces in space combat. Area jammers and nuclear "white-out" patterns are typically used to obscure enemy view of friendly penetration for just this reason

Wil correctly wrote that identifying jump destinations by watching jump entry is possible. Sadly, I know too many of you will immediately conflate that possible with automatic.

When you read the passage I quoted, pay close attention to the many qualifiers used in the description. Penetration can be detected. Detection requires a hard fire control lock. Three different sets of data, penetration angle, jump envelope configuration, and entry vector, must be observed. Proper analysis can allow a prediction of likely jump distance and direction.

Along with the many qualifiers used, pay close attention to how such detection can and usually is prevented or spoofed.

Observers can predict a jumping ship's likely destination if a number of prerequisites involving detection and analysis are met. Such predictions are not automatic or easy nor can such predictions be made beyond fire control lock ranges.

Thank you for the information, as I have no access to Regency Sourcebook. In any case you need all this information to assume the destination with any likehood, but I guess with less data you can at least have some clue.

As an example, if you have some neutrino (passive) sensors in GG moons, able to have a passive lock on the ship in question and to tell the magnitude of the energy used in the envelope (after all that's neutrinos specialty), you can tell the aproximate distance it is jumping to (at least if it's on the AUs range, and so a microjump, or in the parsecs range, and so outsystem).

Of course all this is inferring from the (very limited) data I have about the possibility to tell jump destination, and so may well be wrong assumption.
 
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Not interested in contributing to this board.
 
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Hi,

I agree that the situation is very exploitable. In fact it hits on one of the big issues with the defense of a solar system on an operational level, that of "time" being another of the key factors or "dimensions” that a combatant can try to exploit. Or put another way, the combatant that can best make use of “time” issues, as well as those of the other 3 dimensions normally considered in a battle, may be able to can an advantage over his or her enemy.

Because of the nature of the Newtonian “maneuver” drives and the non-Newtonian Jump drives, distance between the inner and many of the outer planets in a typical solar system may be on the order of at least one week (plus or minus a small amount), and as other have noted in a situation where a gas giant is not heavily defended, an attacker can often expect nearly a week (plus or minus a small amount) before the reinforcements for the defender can likely be expected to arrive. As such, if he/she can arrive in system at the gas giant, overpower the local defenders and refuel I less time than this, then there would seem to be little else that the defender might be able to do.

Other issues that may come into play in a more operational level game than just a tactical level game may include such things as trying to exploit gravity to an advantage. For example, in a purely tactical setting it may not be all that big a deal if we were to assume that all ships on the playing field are treated equally. However, if we are looking on a more “operational” level, where say travel on maneuver drives from some of the inner planets of a solar system may be part of the maneuvering that may go on in a battle, then a ship moving inwards from a higher orbit band to a lower orbit band (say going from the asteroid belt to Mars in our solar system) may have an advantage over a ship moving from a lower orbit band to a higher one (such as going from Earth to Mars in our solar system) because the ship moving from a higher band to a lower one will have the Sun’s gravity acting with its own acceleration, while a ship moving outward from a lower band to a higher one will be acceleration against the Sun’s gravitational pull.

Other issues that a clever opponent may look to try and exploit may even include things like the fact that a defending ship operating in orbit around a planet, which in turn is orbiting a star actually has a fair bit of initial velocity due to it orbit around the star that a ship just jumping into system may not necessarily have.
 
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Not interested in contributing to this board.
 
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Hi,

I'd really like to see something along those lines too and I think you hit on a lot of the key stuff, and you're probably right that it needs to be fairly abstracted in some/many ways.
 
One thing that concerns me about using High Guard to resolve tactical battles though, is that for some reason, maybe because of the Newtonian movement, spinal mounts and acceleration rates stipulated in Traveller, I just have trouble seeing the actual battles resolving in a manner consistent with the rules of High Guard (if I am understanding them correctly).

Overall, the more I try to envisage what a battle between two fleets in a Traveller type setting, the more I'm left wondering if such battles may look more like a cross between "Napoleonics" and US Rules Football with maybe a little bit of WWII and modern jet age aerial combat thrown in. Specifically, rather than ships lining up for extended battle side by side I wouldn't at all be surprised to see forces approaching headlong with the front shifting and moving as each side tries to block, feint, sweep, and/or push through the front lines, while some high acceleration forces capable of reaching high velocities may also be used to sweep in through and/or around other forces kind of like a high tech "cavalry" cutting behind the front lines, causing disruption etc (but all in 3D).
 
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I think I could certainly shed some light here.
You see, I've actually run (and I'm still running) a naval campaign, with myself in the role of the captain. I've actually dealt with operational level details, and IMTU I've done tons of thinking about how things would work.

First off, the assumptions.

My universe is a 'low tech trav,' with ships limited to a max of 12000 tons. Corvettes (the book 2 Type T is typical) run a few hundred tons, frigates 1000 tons, destroyers 2000 tons, cruisers 4000-6000 tons (5000 tons is the most common), and most battleships 10000 tons, with flagships at 12000 tons. It uses the 'beyond book 2' rules from the freelance traveller homepage, with some modifications of my own (missile bays launch 8 per turn, hold 5 turns of firing). The main ship-killling weapon is the bay missile, 1 dton and 4 metric tons each.

Pretty much everything but a corvette is jump-2, since any higher would greatly restrict combat potential. Corvettes, which would lose to any larger warship in any case, are jump-3. Cruisers are 4-6g, smaller ships usually 6g, and battleships 3g. Ships can take punishment - over a hundred bay missile hits for a battleship is needed to reduce it to a wreck. (I would like to point out that I use full vector movement, and that includes missiles as well.) Detection range is 60 classic traveller range bands of 10,000km each, with 1000 second turns. Smaller ships have shorter detection ranges. Radio communication is possible throughout the system, but tight beam communication requires knowing where the intended receiver is (planets are always known, but ships effectively require it being in sensor range or a pre arranged location. Otherwise, anyone is the system could pick it up).

The all-important jump drive assumptions:
It isn’t possible to determine the direction of another ships that jumps. However, ships that jump to a planet (or other similar object) always arrive at pretty much the same point, with that point being different for each system in jump range. Ships that jump together arrives spread over a few range bands at that point, and over several turns. Critically, it takes 500 seconds before the maneuver drive can be used (although this applies to ships waiting around in the system as well.) Minor misjumps are somewhat common, mostly with unskilled crews, but only at most several AU and a few days off. Jumping into interplanetary space scatters ships over a few AU and a few hours.
 
Back to the topic of the thread, defending a system.

Usually, you won’t have a fleet to defend a system. Instead, it has to cover several systems from the opposing fleet. Most of the systems don’t have to be defended, and if the enemy wants to bother to send an occupying force of a company or two of troops, then so be it. We can kick them out later with just as little effort. (there's a campaign nugget right there: a frigate and a half dozen or so freighters of a few hundred tons, now capture/recapture a planet with a total pop of 5000 in a few settlements. Don't forget the local militia - you only have a few hundred troops, so they matter. No one will ever likely get famous for this, so it's a thankless job.)

The few major worlds have significant planetary defenses. Nuclear dampers pushing detonation distances of warheads out to 10s of kilometers means that you can’t normally just nuke hardened defenses. Missile silos have hatches thick enough that even a direct hit from a laser or anti-ship warhead (nuclear shaped charges) might well not go through it. Laser defenses of light turrets can pop out of hardened tunnels, take a shot, then pop back in.

That said, a battle fleet has enough laser firepower to keep the fixed defenses suppressed by continually hitting hatches and tunnel openings with laser shots. Anti missile fire can keep casualties among landing boats to an acceptable level against most defenses. A fleet overhead provides incredible direct fire support from low orbit.

But, a fleet can’t stay there. After several hours they must repressurize at least part of the ship so the crew can eat and drink. After several hours of firing, the ships have to cease firing to allow the lasers and drives time to cool off. The defenders know this.
The defenses will have large numbers of bay missiles attached on a solid rocket booster stage (M-drives don’t work in an atmosphere) on mobile launchers. They will pose an endless pain for a fleet overhead. It is next to impossible to track down and destroy them. See the experience of Iraqi Scud’s during the Gulf War – few were actually destroyed, despite intense efforts to find and destroy them. A bay missile on a boaster is the same size. And a fleet in orbit has far less ability to find them then the Coalition did, and they can be on any landmass over an entre planet. Missile submarines can hide deep in planetary oceans, immune from counterattack, and occasionally launching salvos of missiles.

Any fleet in orbit will be subjected to frequent and completely unpredictable attacks from lasers and missiles. There often won't be time to charge the lasers for anti missile fire, so they all will hit. They won’t do much damage each time, but sooner or later one will hit something vital, or hit a pressurized compartment full of crew out of their vacc suits. Fire control good enough to hit a ship in low orbit can be mounted on a tripods and carried by a few men – after all, a ship is often the brightest star in the night sky.

The ships can’t take this forever, and so while they can come into close orbit and cover a landing with little damage or losses, they can’t stay there. Instead, they will be reduced to staying at long sensor range of the planet, and posting picket ships in other directions. Just as often, they will instead begin a campaign against the opposing fleet.

Defeat of the forces defending the planet isn’t assured, either. Both sides will have forces in the 100,000’s or more. If the planet is important enough to defend, it will often have a population in the millions. Some raw recruits can be drawn from the population, and small arms ammunition and minor supplies can be manufactured on the planet. They can often hold out for a few years if the attacking force can’t capture the planet’s industrial base.

But if the tide of a campaign turns, it can be almost enough as much trouble forcing the surrender of the attacking force. Since a guerilla war on a planetary scale is essentially endless, it is greatly frowned upon by major powers. The surrender of conventional forces usually requires avoiding that, as well as many conditions designed to allow securing the planet, such as the surrender of all planetary defense bunkers, and all military submarines.
 
Overall, the more I try to envisage what a battle between two fleets in a Traveller type setting, the more I'm left wondering if such battles may look more like a cross between "Napoleonics" and US Rules Football with maybe a little bit of WWII and modern jet age aerial combat thrown in. Specifically, rather than ships lining up for extended battle side by side I wouldn't at all be surprised to see forces approaching headlong with the front shifting and moving as each side tries to block, feint, sweep, and/or push through the front lines, while some high acceleration forces capable of reaching high velocities may also be used to sweep in through and/or around other forces kind of like a high tech "cavalry" cutting behind the front lines, causing disruption etc (but all in 3D).

There's a reason Book 5 is done the way it is. If you're using Book 5 combat in a "Mayday" style "tactical" environment with G's of maneuver, and vectors, and counting out range hexes, you'll discover maneuver pretty much doesn't matter. 3D, heck 2D, doesn't matter. Facing, speed, weapon arcs...don't really matter. Range matters...sorta.

Imagine two guys with cannons in a bull ring. That pretty much sums up space combat, especially with Book 5, or TNE. You're either in effective range of each other (and blasting away) or you're not. It's not a game of maneuver. It's a game of "If it's in range, I can hit it. If I hit it, I can crit it. If it crits, it kills."

GDW figured this all out playing with Book 5, and basically came up with "You know, all this vectors and hexes and drawing chalk on the ground or pushing counters on empty maps isn't really fundamental to the end result. So, we'll just speed it up by making it a mutual firing squad with a conceptual reserve." Most book 5 battles are done before the first dice are rolled, the dice are there just to see how much it costs the victor.

Brilliant Lances and Battle Rider do a really good job of demonstrating how complicating the procedure by adding realistic maneuver (of which they do a really good job) doesn't really change the overall outcome. BL does add the capability of adding temporary terrain using missile nukes and whiteout to break lock. I've never played a big enough game to really see that come in to play, perhaps it does to some extent. Terrain makes maneuver relevant. As a general rule though, there's not a whole lot of terrain in space.

And it is different with small ships poking holes in each other with lasers, especially in something like BL. When it's small ship lasers vs small ship lasers, there's not a lot of crits involved, it's more like killing a watermelon with an knitting needle. But bring on the big guns, and all that pin cushion stuff goes by the wayside. It's shotguns vs watermelons. "I roll 10 hits with the knitting needles and one with the shotgun. Which damage should I roll first?"
 
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If you reduce Max weapon ranges to less than one turn's delta-V, ranges start to become important. If facing matters (and limits vector changes), maneuver matters. HG was built on some shaky assumptions ... And maneuver mattering disappears in them.
 
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