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Theemile wrote:

cthia wrote:But where are they placed? And why in orbit? Considering orbital mechanics, we know why orbits are used. Earth's gravity turns the satellite into a hybrid engine system. It saves on "gas." Energy isn't a problem for something that has a wedge like the forts, and I can't imagine a fort in geostationary orbit simply to protect Mount Royal and the Queen. So where in orbit would they be placed, low, medium, high? Why would an orbit even matter for a fort, which has a wedge?

You put things that don't need orbits into orbits so you can let them turn off their drives every once in awhile... and so that things in orbits that need orbits don't slam into them.

Besides Geosync orbit is still considered "knife fighting in a Recreational Vehicle's Coat Closet" range in the Honorverse. It's 1/3rd the range of the PDLCs!

so high orbit - very high....

We have several references to Havenite planets during Cutworm who deployed their pods to planetary poles for system-defense purposes, particularly the planets we got good looks at during Cutworms I and II such as Chantilly (Home of Admiral 'Sneaky' Bellefeuille and her Smoke & Mirrors defense trick)


So I would believe that any planetary "orbiting" fortress are in similar high polar 'orbits', where it's more static position than true orbits. 1-4 fortresses permanently at both planetary North, and South you have near 360° coverage around the clock, and rotating active-duty between them to enable their impellers to possibly account for drift.


And on that subject actually, depending on their altitude they could damn near minimize the drift to start. By parking in more of a solar orbit, just outside the planetary Sphere of Influence (SOI), the gravity from the planet in question is near negligible. They'd still close enough to act as a "close-in" fortress, but far enough away they can minimize how much gravity is going to cause them to truly orbit the planet and risk being caught on the wrong side and thereby unable to fire at invaders.


For Earth specifically, our SOI is approximately 0.929x10^6 km (929000 km); so if you left a fort to Earth's polar north at say approximately 0.935x10^6 km; then Earth would have very little gravity influence on it, and it could hold position with minimal engine input for years. But it's still (barely) within maximum graser range of anything trying to enter Earth orbit so any attackers must kill it as they approach regardless of direction; with another fort stationed to the Earth South preventing that approach angle.

Somtaaw wrote:For Earth specifically, our SOI is approximately 0.929x10^6 km (929000 km); so if you left a fort to Earth's polar north at say approximately 0.935x10^6 km; then Earth would have very little gravity influence on it, and it could hold position with minimal engine input for years. But it's still (barely) within maximum graser range of anything trying to enter Earth orbit so any attackers must kill it as they approach regardless of direction; with another fort stationed to the Earth South preventing that approach angle.

I don't think most Manticoran forts would be that high up. They'll be low enough and spread around the planet that their PDLC baskets(~100,000km radius) masks the whole planet from every direction, preferably with lots of overlapping.

One reason to keep most forts in a lower orbit is to be able to concentrate them more quickly, so they can form an interlocking wall of battle between the planet and any identified hostile forces.

cthia wrote:Interesting. Pods certainly existed then, albeit I can't remember how capable Haven's missiles were. Regardless, they were always good enough to remain in shouting distance of the RMN until some Manty archaeologist discovered the diary of Apollo. My point is that I can imagine missile performance would greatly affect the placement of forts. Was that the case here?

Also, was the fact that there was so much internal strife on Haven part of the reason there were forts in orbit? Which makes one wonder why Saint-Just didn't use them against the navy.

Apollo armed forts could probably be strategically placed anywhere.

During the single drive missile era you probably want the forts at least far enough out that enemies have to enter the fort's energy weapon range before they get close enough to fire missiles at the stations and yards behind them - so 8 - 10 million km further from the planet than the stations and yards. Even if the attackers are willing to lob missiles that'll burn out and continue ballistic they have to survive the entire defensive envelope of the forts and then the stations and yard (which in Manticore at leas have their own point defenses) get time to sort out the leakers and get their own CMs and PDLCs into play.

In the era of MDMs, where that's not practical (missiles can always coast before activating their final stage; and the number of forts you'd need to have a protected shell of them out at 70 million km is way more than at 10 million - surface area went up 49 times but point defense range maybe doubled once you give the forts the Mk31 CMs)

But even with MDMs you'd still, I think, want the forts just as far out so that missiles fired at the stations and yards still have to fly through the fort's entire defensive envelope, getting attritted, and then the stations defenses still have time to sort out and engage and leakers.


As for Haven's forts, I don't recall the books saying how far out they were. But even with Saint Just's paranoia about the reliability of the Peep navy the forts were still orbiting far enough out that Capital Fleet's anchorage was between them and the plant. Because I do remember than in the short story about McQueen intervening against the Levers that even though her waller moved without orders and dropped pinaces and assault shuttles on the capital (triggering worry that she was taking advantage of the chaos to launch a coup) the forts couldn't fire on her because of risk of hitting the planet behind her.
So the forts probably aren't there to help with internal strife and they're nearly impotent against it. (Now keeping the other Peep fleet's from flying the Haven to launch a coup - that's they're well positioned to help resist. But anything launched on the planet - or even by Capital Fleet - they're not in a position to resist. Or at least not without risking major devastation to the capital)

Jonathan_S wrote:During the single drive missile era you probably want the forts at least far enough out that enemies have to enter the fort's energy weapon range before they get close enough to fire missiles at the stations and yards behind them - so 8 - 10 million km further from the planet than the stations and yards. Even if the attackers are willing to lob missiles that'll burn out and continue ballistic they have to survive the entire defensive envelope of the forts and then the stations and yard (which in Manticore at leas have their own point defenses) get time to sort out the leakers and get their own CMs and PDLCs into play.

That's a LOT of forts. Area of a sphere is 4PiR^2. So 10 million km gives you a surface of 1256 million square km. Assuming you have a 0.5 Mkm energy weapons range (with overlap) each one will cover 0.78 million square miles. So you need 1600 forts.

Do you think you'll get 1600 forts?

kzt wrote:

Jonathan_S wrote:During the single drive missile era you probably want the forts at least far enough out that enemies have to enter the fort's energy weapon range before they get close enough to fire missiles at the stations and yards behind them - so 8 - 10 million km further from the planet than the stations and yards. Even if the attackers are willing to lob missiles that'll burn out and continue ballistic they have to survive the entire defensive envelope of the forts and then the stations and yard (which in Manticore at leas have their own point defenses) get time to sort out the leakers and get their own CMs and PDLCs into play.

That's a LOT of forts. Area of a sphere is 4PiR^2. So 10 million km gives you a surface of 1256 million square km. Assuming you have a 0.5 Mkm energy weapons range (with overlap) each one will cover 0.78 million square miles. So you need 1600 forts.

Do you think you'll get 1600 forts?

Good point. Though normally you see the enemy coming. And while slow, at under 100 gees, forts can change position. Maybe they normally orbit closer and then when an enemy fleet is seen approaching they concentrate down that threat axis.

Then you'd just need enough forts to create an adequate defensive bubble on a particular threatened segment of the total sphere.

Even against MDMs that kind of works. The missiles have enough endurance to skirt the total defensive bubble of the forts and still cut back after the targets behind them. But they'd have to alter vector so radically they'd cut off fire control telemetry from the launching ships - so they'd be much less effective.

Jonathan_S wrote:

kzt wrote:That's a LOT of forts. Area of a sphere is 4PiR^2. So 10 million km gives you a surface of 1256 million square km. Assuming you have a 0.5 Mkm energy weapons range (with overlap) each one will cover 0.78 million square miles. So you need 1600 forts.

Do you think you'll get 1600 forts?

Good point. Though normally you see the enemy coming. And while slow, at under 100 gees, forts can change position. Maybe they normally orbit closer and then when an enemy fleet is seen approaching they concentrate down that threat axis.

Then you'd just need enough forts to create an adequate defensive bubble on a particular threatened segment of the total sphere.

Even against MDMs that kind of works. The missiles have enough endurance to skirt the total defensive bubble of the forts and still cut back after the targets behind them. But they'd have to alter vector so radically they'd cut off fire control telemetry from the launching ships - so they'd be much less effective.

Your're assuming that they are the main form of defense kit. Another piece in the inventory was the wedge buoy. A device the size of a FF to CL with a DN-SD wedge and a fusion reactor - usually kept at readiness at all times. A cloud of these would be used to create a missile shield for a planet (or other defensible position.

I considered the poles, because there the forts would be out of everybody's way. But that doesn't seem to be an optimum placement for firing lasers down on the planet during insurrections, or whatever planetary assistance may be needed. Usually nothing important is located at the poles. I was worried about a pronounced axial tilt, which would put both poles too near the plane of the ecliptic. The poles, considering⁠—and since I found out about—Manticore's negligible tilt, wouldn't have that particular problem, but yet has another. Location at Manticore's poles would seem to give an attacking fleet coming in on the plane the best shot at the forts.*

The talk of OWPs being assistance to falling debris further hampered my logic, and the forts placement, because the "drunken" wiki says OWPs are there to protect the forts? Or some sort of symbiosis. I sure as hell can't figure out why a fort would need protection, but if true, the placement of forts has to be within an OWPs energy basket. And they both have to be close enough to the planet if their lasers are to be of any assistance down on the planet.

Jonathan's notion of a shell of forts about the planet sounds reasonable, as long as they remain within each other's light speed envelope.

If that puts them further out of the system than the space stations, firing on forts would also give an attacker worry about hitting a civilian installation as well as the planet, which is never mentioned. So maybe it is the space stations that are located at the poles.

At any rate, I just couldn't see forts in the more traditional close-in orbits as it seemed to be suggested. Although several million KMs further out seems more likely. In that developed position, their immense firepower is more effective.

Another thing that bothers me, and has been mentioned, is the fact that you want to intercept an attacking force before it gets anywhere near the planet. The further out the forts are located, the further out they can intercept an attacker. (Which is why I think missile range should greatly affect placement.) UNLESS, they are reserved for the last line of defense. Which seems unlikely, and foolish. If Home Fleet is gone, the situation is useless and the forts are little more than a nuisance.

*Then there's kzt's notion that stirs the pot . . .

kzt wrote:No, a fort has a wedge and can maneuver itself at 30-50g.

It has no significant tactical mobility, but is is operationally mobile inside the system.

Altho that would appear to ring true, they must have some tactical mobility. And it seems their placement would take that mobility into account. Jonathan has posited one tactic that would take advantage of that mobility.

At any rate, I always imagined the forts moving and optimizing their positions depending on the profile of the enemy. Perhaps that wouldn't be a good idea because another prong of attack could catch one or more out of position. At the very least, it seems they would either maneuver to keep the planet behind them or move away from the planet at a position where return fire wouldn't hit the planet.

Wrapping this up. Before all of the talk of fort placement, I assumed the optimum position using the range of their missiles would be further out, 5-10M KM. I whittled it down to 1-2M KM when the discussion began.

What prompted my going off on a tangent, is realizing that forts are effectively a blockade (a shell as Jonathan puts it). If the Lenny Dets are as successful as German U-boats, they will easily penetrate the bloackade. The further out the forts are emplaced, the more disastrous that penetration becomes.

The wiki also corroborates Theemile's post about Haven having orbital forts. It listed three of them. Liberty, Equality and Fraternity. Albeit, doesn't state at what distance they orbit.

cthia wrote:*Then there's kzt's notion that stirs the pot . . .

kzt wrote:No, a fort has a wedge and can maneuver itself at 30-50g.

It has no significant tactical mobility, but is is operationally mobile inside the system.

Altho that would appear to ring true, they must have some tactical mobility. And it seems their placement would take that mobility into account. Jonathan has posited one tactic that would take advantage of that mobility.

The very first book mentioned one tactical movement plan for the junction forts - when resisting a hostile transit

On Basilisk Station wrote:Nonetheless, heavy losses could be anticipated in the inner fortress ring under the best possible circumstances, so the "forts" in the outer rings had to be able to move to fill in the gaps and mass upon an attacker. Their maximum acceleration rates were low, well under a hundred gravities, but their initial positions had been very carefully planned. Their acceleration would be enough to intercept attacking forces headed in-system, and their engines were sufficiently powerful to generate impeller wedges and sidewalls to protect them.

That's not a long tactical movement - but it is mentioning that they'd reposition to restore tactical positioning as other forts are lost.
That means Manticore's doctrine for junction fort usage, at least at that time, valued placement about the full 360 protection of a bubble walls. Especially if the forts need to charge inwards toward the enemy; meaning that they probably have to face the open throat of their wedge dangerously close to the transiting forces as they close the range. (Of course once they reach the desired possition they should be able to go back to the bubble sidewall and regain that all around protection.

Jonathan_S wrote:(Of course once they reach the desired possition they should be able to go back to the bubble sidewall and regain that all around protection.

I'm not sure the all around protection matters, it's more the all around firepower.

munroburton wrote:

Somtaaw wrote:For Earth specifically, our SOI is approximately 0.929x10^6 km (929000 km); so if you left a fort to Earth's polar north at say approximately 0.935x10^6 km; then Earth would have very little gravity influence on it, and it could hold position with minimal engine input for years. But it's still (barely) within maximum graser range of anything trying to enter Earth orbit so any attackers must kill it as they approach regardless of direction; with another fort stationed to the Earth South preventing that approach angle.

I don't think most Manticoran forts would be that high up. They'll be low enough and spread around the planet that their PDLC baskets(~100,000km radius) masks the whole planet from every direction, preferably with lots of overlapping.

One reason to keep most forts in a lower orbit is to be able to concentrate them more quickly, so they can form an interlocking wall of battle between the planet and any identified hostile forces.

In fairness, at least prior to the SLN adopting Buccaneer and contingency order Parthian Shot... NOBODY shot missiles even remotely in a planets direction. The closest we've come to near Eridani violations, was the Masadan lunatics in HotQ in command of Thunder, and that's only because Masada/Yeltsin aren't signatories and didn't really understand exactly how the Sollies would have dropped on both systems like a ton of bricks.

During Cutworm, Henke was really hesitant about long-range firing at the pods near planets like Chantilly. BoManticore, when Tourville's Third Fleet was charging in, Manticore SPECIFICALLY chose not to fire from orbital platforms, so as not to give Tourville 'a reason' to fire anything at all in a planets direction, regardless of whether it could be considered Eridani violation or not. Finally even the Alignment were (mildly) hesitant about openly violating Eridani Edicts for Oyster Bay and they chose the strategy they actually used as a compromise between effectiveness and "we really REALLY don't want Eridani violations this early in the game". IF Manticore had been able to somehow finger Mesa for blatant Eridani violations with acceptable proof, none of the Alignment leadership would have been able to evacuate Mesa before multiple Frontier Fleet squadrons blockaded the whole system.


Having a ring of forts actually on the equator, or any actual orbits of any altitude would ENCOURAGE "accidental" Eridani strikes. As long as you can provide bridge recorder logs where cybernauts can verify it's not doctored, to show you were actually aiming at the fort and a missile failed to properly arm before slamming into a planet. Even pre-MDM era missiles at terminal velocity slamming into a planet is damned near asteroid levels of destruction.


Until Oyster Bay, nobody EVER saw that sort of attack coming, textev alone from I think Honor among others, straight out say if they'd had just 15 minutes warning, the tugs would have been online and blocking Hephaestus/Vulcan/Weyland and the damage would have been mitigated, even against the graser torpedos.



Polar "sitting" forts, are just close enough to engage approaching hostiles with both energy weapon and missiles, but they're far enough away that "accidents" won't result in your own planet getting slapped with one or more 100t+ capital missiles. You're giving up the ability to deal with massive debris, but again pre-OB that sort of 'need' was never ever required in any form.


Aside from the Apollo system defense pods that the Grand Alliance would stock near their forts, both near Junction and planetary forts; they don't need many OWP's designed to aim down at planets. Manticore, Sphinx, Grayson, Beowulf and various other capitals are civilized planets with HAPPY populations with little to zero terrorist activities. Even Haven under the height of the Public Safety reign of terror had exactly ONE uprising, and that was dealt with by Admiral "Clusterbomb" McQueen, and not OWPs or even similar KEW systems like the Damocles that Terekhov used on Mobius.


OFS protectorate planets, due to how they're controlled by dictators and despots needed OWP's, and even there, 90% of them required Frontier Fleet to handle the KEWs, rather than doing it themselves. This heavily suggests OWP's are not common weapons, and most if not all orbital weapons are designed to aim outwards at foreign threats rather than domestic ones. Literally the only OWP's we've ever seen capable of downward fire are the FiE ones around Masada, the ones that Theisman's battleships were going to knock out so Haven could land transports full of weapons for Masadan use.