Mahan goes to some lengths about using terrain and weather... Much of Mahan's tactical and supertactical doesn't apply. Strategy, however, and geopolitical thinking, do. So it matters which parts of Mahan one's applying.
Defense of a Solar System
- Thread starter PFVA63
- Start date
Mahan goes to some lengths about using terrain and weather... Much of Mahan's tactical and supertactical doesn't apply. Strategy, however, and geopolitical thinking, do. So it matters which parts of Mahan one's applying.
Giving the other guy an equal chance is for duels and fools. :devil:
(Ooh, I like that. Might make it my motto!)
Even when resources are equal, the victor tends to be the guy who is most effective at finding ways to apply them unequally. You defend here, he attacks there. Your world with the planetoid batteries remains secure - while the colonies around it are repeatedly sacked until they threaten to secede.
Hi,
After looking some stuff up on the internet and using our solar system as an example, it looks like (just sticking with the basic equations from CT for now, for simplicity) if a defender were to concentrate his fleet near Earth and an attacker were to jump into system at/near Neptune, then even if the two planets are at their closest, it looks like it would take about 4 hrs or so to detect the incursion. Then if the fleet (or at least a part of the fleet were to immediately depart at maximumm accelleration, with a flip midway (per the formulas in the Traveller rulebook, it would take just under 16 days for the defenders to reach Neptunes orbit.
Of course the time could be shaved by a bit if the defenders don't flip at exactly the midpoint and thus don't slow completely once reaching Neptune, but even if the time could be reduced to just 2 weeks it would seem likely that the attackers would likely have refueled in less time than this.
I suppose that an alternative might be if the defenders were to make a micro jump from just outside Earth (which I believe is outside the Suns 100D limit) and jump to near Neptune. However since it would take about a week for this micro-jump (if I am understanding the rules correctly) the attacker's fleet may long since moved on as well.
In the end then, if other systems are in any way similar to Earth's I would begin to suspect that in an environment where there may be a fear of enemy fleets, marauders, or such entering the system concentrating defense forces at/near the high value planets etc in system may not be a fully viable concept. And thus dividing up the defensive forces may be necessary.
As such, I'd suspect that for systems within a few "hexes" of the border in areas near the Zhodani border, Vargr regions, and maybe even the Solomani Consolate may require a more extensive defense, at least in times of strife or rising tension.
After looking some stuff up on the internet and using our solar system as an example, it looks like (just sticking with the basic equations from CT for now, for simplicity) if a defender were to concentrate his fleet near Earth and an attacker were to jump into system at/near Neptune, then even if the two planets are at their closest, it looks like it would take about 4 hrs or so to detect the incursion. Then if the fleet (or at least a part of the fleet were to immediately depart at maximumm accelleration, with a flip midway (per the formulas in the Traveller rulebook, it would take just under 16 days for the defenders to reach Neptunes orbit.
Of course the time could be shaved by a bit if the defenders don't flip at exactly the midpoint and thus don't slow completely once reaching Neptune, but even if the time could be reduced to just 2 weeks it would seem likely that the attackers would likely have refueled in less time than this.
I suppose that an alternative might be if the defenders were to make a micro jump from just outside Earth (which I believe is outside the Suns 100D limit) and jump to near Neptune. However since it would take about a week for this micro-jump (if I am understanding the rules correctly) the attacker's fleet may long since moved on as well.
In the end then, if other systems are in any way similar to Earth's I would begin to suspect that in an environment where there may be a fear of enemy fleets, marauders, or such entering the system concentrating defense forces at/near the high value planets etc in system may not be a fully viable concept. And thus dividing up the defensive forces may be necessary.
As such, I'd suspect that for systems within a few "hexes" of the border in areas near the Zhodani border, Vargr regions, and maybe even the Solomani Consolate may require a more extensive defense, at least in times of strife or rising tension.
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I think you have it reversed.
Let's retreat back to that Age of Sail analogy. Earth's oceans are huge - but until the advent of aircraft, radar, and satellites, battles tended to happen at pretty predictable points: along movement routes, in the waters outside a key port, certain choke points and so forth.
Your fleet jumps in around Neptune, the enemy's most likely to leave you alone. Chasing you invites the risk that you are a decoy intended to draw him away from the most important local target. Conversely, there's not much worth having out near Neptune - and there's a huge lot of terrain to defend if you start counting iceballs and other hydrogen sources. You really can't stop him from passing through; best you can do is to defend what's most important and communicate his presence to the rest of your fleet so they're ready if he continues through.
If he can assemble the force to do both jobs, he'll chase you. If he can assemble the force to defend his target while making the gas giants unhealthy for you, he'll do that. Otherwise, he's most likely to focus on defending his most vital target while trying to cut your line of supply in another system, so you'll be persuaded to leave on your own when your food runs out. To do different is to invite you to concentrate and kill his divided defenders piecemeal.
Timerover51
SOC-14 5K
I'd argue that a Stealth probe could be done. Not easy, but doable. I can think of several situations, including but not limited to turning a rogue comet into a probe and sending that through. The secret is not being totally invisible but looking like something that won't trip alarms. And yes, it would take awhile but if it is a strategic system, you could get some good basic info. Back it up with some spies traveling through to get updates a few weeks before the invasion. Humanti isn't perfect, you play on the weaknesses of the watchers and be devious...
Let us think about that "rogue comet" idea. First, you would need to identify the comet, and in a very short time, determine its potential path and then add your probe. Comets, while they do travel fast, normally take months to traverse part of a solar system as they do a swing around the star and then head back out. So, several months to years after you put your probe into the comet, you would get a snapshot of that part of the solar system that was near the comet path.
You are using a stealthed scout far beyond reasonable detection range, and putting a probe in a ballistic flight through the system.
First, if you put it into a non-powered ballistic path, then you will get a elliptical cometary orbit that does not cover the entire system. You would not be recovering at a point opposite the first jump location, but more than likely at a point within 90 to 120 degrees displacement from the initial point. That holds true unless you have the probe moving at a very high velocity, beyond the star's escape velocity. In our solar system, that would be, at the orbit of Mercury, about 151,000 miles per hour.
Next, using our solar system as an example, there are four gas giants that could be potential refueling sites, from Neptune at about 30 AU to Jupiter at 5.2 AU. Because of the need to give the probe a very high velocity, you drop it off at about 40 AU. You accelerate it to 10 million miles per hour, which as pointed out earlier will take about 5 days at 6G acceleration. So, either your scout has to be going that fast, or the probe has to be able to achieve that velocity on its own. At 10 million miles per hour, your probe covers an AU in roughly 9.3 hours. You want to check the outermost gas giant, Neptune, and the Earth, so your probe's path has to be close enough to those planets for its passive detection systems to work, and the planetary alignment must be such that the probe's path does not intersect with the Sun, or pass too close to it. So, you drop it off at 40 AU and pick it up at 30 AU, Neptune now being on the opposite side of the Sun. Total distance covered, 70 AU, multiply that by 9.3 hours, which is equal to 651 hours, or 27.125 days, or just under 4 weeks. Now, there are three other gas giants to cover, along with 3 additional planets, I am not counting Pluto because it is simply so far out, which you may not get any information on depending on where they are located in relation to your probe. That also does not include the Asteroid Belt.
Have you gained complete information on the system? I would submit that you have not, unless your probe's passive detection systems are so incredibly sensitive to detect ships at ranges of a billion miles or so. If your passive detection systems are that good, why are you bothering to use a probe? Simply send a few scouts in to jump a billion miles from the target planets, run your scans, and then jump back out.
Timerover51
SOC-14 5K
That makes one light day equal to 173.97 AU. As an AU is about 93 million miles, one light day is equal to over 16 Billion miles. Assuming that by a "few" you mean somewhere between 3 and 7 light days, you are looking at detecting something at a distance of between 48 billion and 112 billion miles.
Timerover51
SOC-14 5K
Shift your thinking and ask yourself, "What would I attack if I were attacking this system?" The answer is the high value planet or planets. It is a bit like the old question of "what is the best way to hunt submarines?" Patrols over the entire area which they can operate in, or do you concentrate your resources near the targets, in the case of submarines, you concentrate your targets into convoys, and put your escorts there. The submarines have to come to you if they want to do any damage.
If you spread your forces out to cover the gas giants, especially in a system similar to ours, where you have 4 of them, plus the option of Pluto, you are inviting your enemy to pick off your ship detachments one at a time, before you can intervene with any additional forces. And your ship detachments, depending on the distance, cannot get back to cover your high value planet in time to be of any good.
What you are thinking about it basically what the Germans tried in World War One in the North Sea, where they kept trying to catch small detachments of the Grand Fleet without adequate support, and hit the detachment with the entire High Seas Fleet. The bait the Germans used in World War One was the raids by the battlecruisers on the east coast of Great Britain. Jellicoe's response to this was keep the Grand Fleet concentrated, use the Battlecruiser Fleet as the immediate reaction force, and take the entire Grand Fleet to sea in support of the battlecruisers. The advantage the British had was they did have the larger fleet. However, if that had spread their ships out, trying to cover the entire east coast of Great Britain, then the German "bait and pounce tactics" would have been highly successful.
Spreading out the way that you are thinking would allow an opponent with a smaller or weaker fleet to destroy your force piecemeal.
We can pick up a 200W power system at 30 AU in the IR, subject only to resolution issues (and actually looking).
We should be able to pick up a 500 million watt system to about 1000x that far.
So some traveller ships, whose PPs range on the million Mw, could be detected from a nearby system (even if more than a year after they are there, due to the time those IR would take to reach you)...
Theophilus
SOC-13
So, Let me see if I understand:
I'm the Attacker. I jump into the system and my passive sensors immediately begin to give me information on what "has happened" in the system. For instance, I jump in 1 light week out, I get week old info.
I'm the Defender: You jumped in I see you one week later.
I'm the Attacker: I jump in at the 100d limit of Sol, or 38 hexes out from Earth, I can see and fire at the defender's before they see me. Obviously missiles are sub light, but Laser's, PA's and Meson's arrive on target seconds after the defender know I'm in the system.
It seems to me that if I'm attacking, immediately, I have the advantage. If I jump in out system and refuel before attacking the advantage shifts. If I split my force, ie. attack you while my refueller's hit the GG I can make a firing pass or two, and then thrust out system before you can react. If we both have 6g then you can't catch me as I'm already moving while you have to build up vector.
Plus I don't have to engage your mobile force. If I hit stationary planetary target's, Orbital installations (ie Highport, fuel storage, repair facilities), and in system infrastructure targets. (ore carriers, mining ships, fuel ships, etc) I can get significant damage without engaging mobile defenders.
I'm the Attacker. I jump into the system and my passive sensors immediately begin to give me information on what "has happened" in the system. For instance, I jump in 1 light week out, I get week old info.
I'm the Defender: You jumped in I see you one week later.
I'm the Attacker: I jump in at the 100d limit of Sol, or 38 hexes out from Earth, I can see and fire at the defender's before they see me. Obviously missiles are sub light, but Laser's, PA's and Meson's arrive on target seconds after the defender know I'm in the system.
It seems to me that if I'm attacking, immediately, I have the advantage. If I jump in out system and refuel before attacking the advantage shifts. If I split my force, ie. attack you while my refueller's hit the GG I can make a firing pass or two, and then thrust out system before you can react. If we both have 6g then you can't catch me as I'm already moving while you have to build up vector.
Plus I don't have to engage your mobile force. If I hit stationary planetary target's, Orbital installations (ie Highport, fuel storage, repair facilities), and in system infrastructure targets. (ore carriers, mining ships, fuel ships, etc) I can get significant damage without engaging mobile defenders.
Yes, as I see it, as the detection waves go at light speed.
This would depend on the alertness of the defending forces.
Of course, your forces will exit the jump at general quarters, but they still have to detect and lock on the targets before firing them, giving them some time to go to GQ manwhile.
Also remember that not all your ships will exit jump at once, they will, if according to official errata, along several minutes, and even 2 days appart if not using the errata. If one of them exits jump 5-10 minutes ahead of the main fleet, the advantage has switched to the defender, who will be fully alert (planetary defenses included) while you still have to orient yourself after the jump. You risk to have your fleet destroyed piecimal as they exit jump only to find a fully alerted defense force.
And if your force includes subcrafts (fighters, BRs, etc) you may even find yourself fighting without time to deploy them, and most carriers, being irregular configuratins, are not armored...
As you can see, the advantage for the attacker will depend (IMHO) on the kind of forces (jump ships vs subcrafts and carriers), alertness of the defender and luck (your forces coming dispersed or together).
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Hi,
This is exactly along my lines of thinking. What this implies to me is that;
a) just because an attacking fleet jumps into a defended system is no guarantee that there will be contact between the attackers and defenders
b) the presence of a defending fleet is no guarantee that the attacker won't be able to refuel at a local gas giant
c) as such, a raiding fleet may be able to reach further behind front lines than might other wise be expected, since its no guarantee that defenders will stop them from refueling
d) if contact is made battle may well be a phased affair with 1st contact being made by only limited forces with major forces being much delayed
e) there are many potential widely separated points where an attacker may enter the system, which would be hard for a defender to cover
f) micro-jumps may allow an attacker to 1st jump into a system, refuel and then jump again only to reappear elsewhere in the same system about one week later
In general then, to me a lot of this kind of suggests that "fronts" in a battle (say like in the game "5th Frontier War") may actually be much more porous then may otherwise be expected, with an attacker passing through some systems only stopping to refuel (even if a defending fleet is present) and moving on before a coherent defense is put together.
This will depend on something not too clear in Traveller rules (AFAIK, there are some rules sets I don't know): can be told where a fleet has jumped from its jump vector?
If it can be, then a microjump in an hostile system is a highway to disaster, as enemy will concentrate its forces at the exit point (he has a week to do it) and, if mines exist, put there a true minefield trap, but its ships will be ready there in any case (and in GQ) to "wellcome" the incoming fleet.
If it cannot, thisis a way to have your fleet over the enemy, this time with "recent" intelligence when he thinks you've gone away.
I mostly agree with the rest of your post.
No, it isn't possible to discern Jump destination by watching ships as they jump out.
For what I've read in this forum, this is not so clear. IIRC someone commented that in the Regency Book said the opposite (I must trust whoever said, as I've never read it).
I've no idea about that book. All I know is that every version published since then (17 years) it hasn't been possible to do so.
It's Regency Source Book (TNE). I didn't like TNE and so I don't know much about it nor about its books.
Here's where that was discussed: http://www.travellerrpg.com/CotI/Discuss/showpost.php?p=406339&postcount=69
But you won't arrive for at least 3 weeks. By the time you arrive, even assuming you're burning STRAIGHT through, I've had two weeks to "deal with you" by virtue of prepared defenses.
Or, you jump in closer during that intervening week, so I'm no worse off than if you'd just jumped straight in - your data's 2 weeks old by the time you arrive.
Yes, it's possible to identify the destination of a ship's jump by watching its jump entry. Regency Sourcebook, Referee's Library Data.
Actually, Neither GT nor T20 says you can't - they simply don't mention either way. Same for Hero Trav. I don't recall MGT discussing it, either.
