?

Theemile wrote:I took the Silver bullet panels as keep-alives, to keep a capacitor capable of firing up the reactor topped off until it was needed.

If that were the case wouldn't it be simpler to start the reactor whenever the capacitor fell below a certain power level to build up the plasma charge; rather than using solar panels to trickle charge the capacitor, given that they spoil the stealth effect? Solar panels this far from the central star, really?

tlb wrote:

Theemile wrote:I took the Silver bullet panels as keep-alives, to keep a capacitor capable of firing up the reactor topped off until it was needed.

If that were the case wouldn't it be simpler to start the reactor whenever the capacitor fell below a certain power level to build up the plasma charge; rather than using solar panels to trickle charge the capacitor, given that they spoil the stealth effect? Solar panels this far from the central star, really?

stealth? firing up a reactor has to be noisy. But then how is the gtorp stealthy after the reactor fires up? Got me, I didn't write it.

If the gtorps grasers are powered by capacitors then why do they have to be so large, and why were we presented with Detweiler's musings that the micro-fusion reactor secret hasn't been broken.

Heck why should any Navy's missile have needed a reactor if capacitors would suffice. Until the Apollo program's power needs came along anyway.

cthia wrote:If the gtorps grasers are powered by capacitors then why do they have to be so large, and why were we presented with Detweiler's musings that the micro-fusion reactor secret hasn't been broken.

Heck why should any Navy's missile have needed a reactor if capacitors would suffice. Until the Apollo program's power needs came along anyway.

No missile used fusion before Manticore introduced the micro-fusion reactor, because capacitors allowed for a smaller size suitable for tube launching. The plasma capacitor provided enough power to supply the missile through the range where the motor burned out (until much more power was needed for things like dazzlers and dragon's teeth).

Do we have any idea of the size comparison between a graser and a laser warhead? Also the graser torpedo needed much more processing power, since it is operating alone; do we know what size increase is needed for that? Finally, I get the impression that the spider drive is much bigger than an impeller drive for the same mass of payload.

tlb wrote:Do we have any idea of the size comparison between a graser and a laser warhead? Also the graser torpedo needed much more processing power, since it is operating alone; do we know what size increase is needed for that? Finally, I get the impression that the spider drive is much bigger than an impeller drive for the same mass of payload.

Need textev for the actual numbers, but it was between a regular missile and an LAC. That's a huge range, unfortunately.

Didn't someone also say that a DN-sized Shark could only carry five of them?

BTW, a DN-sized ship should be able to carry more than 5 LACs, so that factoid isn't really informative or can't be right. Unless the torpedoes are bigger than LACs, but I find that hard to believe.

ThinksMarkedly wrote:

tlb wrote:Do we have any idea of the size comparison between a graser and a laser warhead? Also the graser torpedo needed much more processing power, since it is operating alone; do we know what size increase is needed for that? Finally, I get the impression that the spider drive is much bigger than an impeller drive for the same mass of payload.

Need textev for the actual numbers, but it was between a regular missile and an LAC. That's a huge range, unfortunately.

Didn't someone also say that a DN-sized Shark could only carry five of them?

BTW, a DN-sized ship should be able to carry more than 5 LACs, so that factoid isn't really informative or can't be right. Unless the torpedoes are bigger than LACs, but I find that hard to believe.

A Manticorian small graser is in the 500 ton - thousand ton range at a minimum (and Manty elecronics are small compared to most other producers) so is easily the mass of 5-10 Mk 16s; Each Shark carried ~3 Gtorps externally. (18 used on Hesphateus)

cthia wrote:If the gtorps grasers are powered by capacitors then why do they have to be so large, and why were we presented with Detweiler's musings that the micro-fusion reactor secret hasn't been broken.

Heck why should any Navy's missile have needed a reactor if capacitors would suffice. Until the Apollo program's power needs came along anyway.

They're so large because the volume of capacitors required to power them for long endurance attack runs is much larger than the volume needed for a micro-fusion power plant and fuel.

That's why Manticore developed micro-fusion tech - to allow vastly increased recon drone endurance without making it as massive as it would have to be to achieve the same with capacitors.


Basically the capacitors have a linear volume/power ratio. Want twice the power (for twice the endurance) you need twice the volume of capacitors. Micro-fusion isn't linear - or rather there's a very large minimum size no matter how little power you want from it -- the fixed size of the reactor. But adding additional power past that point requires very small increases in size; just a larger fuel tank - which for most usage is tiny compared to the reactor volume.

If you graphed the volume vs power of both sources there would be a crossover with capacitors being smaller for power amounts below that value and then as you increase desired power they'd meet where capacitors or fusion would be the same volume, past that point fusion quickly become the clear winner. And graser torps, due to their endurance, are probably way over in the area where fusion would win -- if the MAlign had access to it.

For missiles that crossover point seems to be around or possibly just past the power requirements for two 60/180 second drives (a DDM). For drones I'm not sure where it is, but for the endurance Manticore wanted out of its Ghost Rider drones fusion was a huge win.

(Remember RDs back in the first few books seemed to have endurances of under an hour and seemed largely restricted to proving ahead along the same approximate vector of a fleet - not spreading out to scout an entire system over days. Microfusion changed that, it must have given Ghost Rider drones one, maybe two, orders of magnitude more power within approximately the same volume drone!)

Jonathan_S wrote:Basically the capacitors have a linear volume/power ratio. Want twice the power (for twice the endurance) you need twice the volume of capacitors. Micro-fusion isn't linear - or rather there's a very large minimum size no matter how little power you want from it -- the fixed size of the reactor. But adding additional power past that point requires very small increases in size; just a larger fuel tank - which for most usage is tiny compared to the reactor volume.

The linear requirements are an assumption.

It could well be above linear, because losses could increase with size. We have no idea what a plasma capacitor is. It's possible that to increase its size you need to increase the number of parts to keep the charged parts isolated. Like a regular capacitor, the more charge you have, the bigger the isolation you need to keep that charge from rupturing the isolation medium's resistance.

Say it's a simple 1:1.25 (4:5) ratio. To double the capacity, you need 2.5 times the volume, and so on. That would mean it gets really bad very quickly.

Another aspect is the fact that it is a plasma and therefore is very hot. Because of the square-cube law, if you were to double the volume, the area would have only increased by 1.587x. That's the surface that dissipates heat. So it's entirely possible that increasing the size also makes for a hotter object, which in turn makes it less stealthy.

To counteract that, a simple solution is to double the area when doubling the capacitor, which means the internal volume increases by 2.82x. In other words, the proportion of the volume of capacitor to the volume of the torpedo decreases. That could explain why the capacitor-based graser torpedoes are so big.

ThinksMarkedly wrote:

Jonathan_S wrote:Basically the capacitors have a linear volume/power ratio. Want twice the power (for twice the endurance) you need twice the volume of capacitors. Micro-fusion isn't linear - or rather there's a very large minimum size no matter how little power you want from it -- the fixed size of the reactor. But adding additional power past that point requires very small increases in size; just a larger fuel tank - which for most usage is tiny compared to the reactor volume.

The linear requirements are an assumption.

It could well be above linear, because losses could increase with size. We have no idea what a plasma capacitor is. It's possible that to increase its size you need to increase the number of parts to keep the charged parts isolated. Like a regular capacitor, the more charge you have, the bigger the isolation you need to keep that charge from rupturing the isolation medium's resistance.

Say it's a simple 1:1.25 (4:5) ratio. To double the capacity, you need 2.5 times the volume, and so on. That would mean it gets really bad very quickly.

Another aspect is the fact that it is a plasma and therefore is very hot. Because of the square-cube law, if you were to double the volume, the area would have only increased by 1.587x. That's the surface that dissipates heat. So it's entirely possible that increasing the size also makes for a hotter object, which in turn makes it less stealthy.

To counteract that, a simple solution is to double the area when doubling the capacitor, which means the internal volume increases by 2.82x. In other words, the proportion of the volume of capacitor to the volume of the torpedo decreases. That could explain why the capacitor-based graser torpedoes are so big.

Fair enough - capacitors aren't necessarily linear. Shouldn't have said that.

Still, it's been stated pretty clearly in RFC posts that, whatever the capacitor size/power graph would look like, they start off with an advantage over fusion and at some point the smaller marginal volume increase needed for more fusion endurance overcomes its large fixed volume "cost" and it become more compact that capacitors holding that much power.

Jonathan_S wrote:Fair enough - capacitors aren't necessarily linear. Shouldn't have said that.

Still, it's been stated pretty clearly in RFC posts that, whatever the capacitor size/power graph would look like, they start off with an advantage over fusion and at some point the smaller marginal volume increase needed for more fusion endurance overcomes its large fixed volume "cost" and it become more compact that capacitors holding that much power.

This is why I could have swore that they had a STARSHIP fusion reactor in them, just like a old fashioned LAC.