The Two General's Problem

ThinksMarkedly wrote:

Note: If sails are only needed in grav waves??? Then can a spider ship raise sails in regular hyper anyway, to also serve as a beacon? IF a spider ship has sails which I do not think it has???

See others' answers for why it must have. I don't see a reason why it couldn't raise the sails and thus be visible in grav sensors.

But they are called sails for a reason, and raising them might make the drift problem worse. Similar to a sea ship: if you drop your sails, you're adrift, bobbing up and down with the waves and only moving along the sea currents; if you raise your sails, you'll be carried by the winds in addition to the sea currents.

As far as we know grav sails can only catch 'wind' in two very specific spots -- within a grav wave and in the arrival/departure grav lanes near a wormhole terminus. So, unless there's something RFC hasn't been telling us, putting up sail in a rift in hyperspace shouldn't cause any acceleration (even if the next hyper wall up is moving relative to you)

(Now if you'd set your rendezvous within a grav wave then sure sails provide propulsion; but you can control their grab factor and so should be able to hold position (at least to the accuracy of your hyperlog's position indication)

Jonathan_S wrote:As far as we know grav sails can only catch 'wind' in two very specific spots -- within a grav wave and in the arrival/departure grav lanes near a wormhole terminus. So, unless there's something RFC hasn't been telling us, putting up sail in a rift in hyperspace shouldn't cause any acceleration (even if the next hyper wall up is moving relative to you)

To be precise, we don't know that they catch "wind" only in those two specific spots. We know they are required at those spots. That does not imply they can't be raised elsewhere (penny's question) nor does imply there's no acceleration elsewhere. It might just be negligible in most regions of hyperspace compared to a wedge, useless for accelerating for a voyage, but still present.

But you're right we don't know that either.

ThinksMarkedly wrote:
Note: If sails are only needed in grav waves??? Then can a spider ship raise sails in regular hyper anyway, to also serve as a beacon? IF a spider ship has sails which I do not think it has???


See others' answers for why it must have.

I don't think that's written in stone. Likely, but not definitely. We simply do not know what amenities a spider-drive system might offer. We can speculate, but that is all. A spider-drive might deliver an even bigger “tax break” for traveling in hyper than our current administration.

ThinksMarkedly wrote:
I don't see a reason why it couldn't raise the sails and thus be visible in grav sensors.

An entire fleet with sails raised should be even more visible.

ThinksMarkedly wrote:But they are called sails for a reason, and raising them might make the drift problem worse.

Dropping the sails would make the drift worse if there is wind and if the ship is not anchored, or if the ship does not have an “outboard motor.” More modern sailboats have outboard motors as backups; there isn't always a wind.

ThinksMarkedly wrote:Similar to a sea ship: if you drop your sails, you're adrift, bobbing up and down with the waves and only moving along the sea currents; if you raise your sails, you'll be carried by the winds in addition to the sea currents.

Adrift implies no control and/or not anchored. If a spider can attach itself to the hyper wall, then it is anchored. A spider also has an “outboard motor,” so, not adrift.

That is, if wind exists in normal hyperspace. If wind exists and the ship is anchored, then the wind could damage the tractors. But these are not grav waves, so the storm should be light. I posit it won't be a problem for the very high powered tractors.

Thanks to everyone who cleared up some of my misconceptions about hyperspace. But if the hyper walls are all around, then that question I asked on page 4 of this thread should be possible. Namely…

penny wrote:Can a ship drop out of hyper from any band directly into n-space?

Jonathan_S wrote:Depends on what you mean by "directly".

The best description we have is one I alluded to in a recent post, the arrival of Honor's convoy to Grayson

Honor of the Queen wrote:The endlessly shifting patterns of hyper space were no longer slow; they flickered, jumping about like poorly executed animation, and her readouts flashed steadily downward as the entire convoy plummeted “down” the hyper space gradient.

Fearless hit the gamma wall, and her Warshawski sails bled transit energy like an azure forest fire. Her velocity dropped almost instantly from .3 C to a mere nine percent of light-speed, and Honor’s stomach heaved as her inner ear rebelled against a speed loss the rest of her senses couldn’t even detect. DuMorne’s calculations had allowed for the energy bleed, and their translation gradient steepened even further as their velocity fell. They hit the beta wall four minutes later, and Honor winced again—less violently this time—as their velocity bled down to less than two percent of light-speed. The visual display was a fierce chaos of heaving light as the convoy fell straight “down” across a “distance” which had no physical existence, and then they hit the alpha bands and flashed across them to the n-space wall like a comet.

So you don't need to stop in each band for the hyper generator to recharge; so in that sense it is direct.

But you do need to pass through each band (bleeding off velocity as you do so) on your way -- so if there was a ship within sensor range in any of those lower bands they'd see the convoy dropping through -- and if within weapons range could try to fire on it.

Your statement isn't clear. I was asking if a ship has to stop in each band on its way to n-space. You say that it does not have to stop. But text says there is a “layover” of four minutes. That is stopping in each band. I am thinking that it should not be possible for a ship to fire on another ship that is performing a crash translation directly to n-space without the four minute delay between bands.

Intuitively, the hyper generator should not need recharging inbetween transiting down from higher bands. I am assuming that since the streak drive needed an oversized hyper generator to “brute force” its way into the higher bands, that a lower band needs less “brute force” therefore logically, descending the bands should require less and less effort from the hyper generator. And since the streak drive employs an oversized generator anyway, the four minute interval between bands should not be necessary. Logically that is, which also is not written in stone.

This becomes important, IMO, because the problem with drift should be more pronounced in the higher bands. And if a ship needs to periodically drop out of hyper and reset the hyperlogs in n-space, then it seems that an n-space coordinate wouldn't be as accurate relative to the iota and kappa bands. But if a spider ship can crash translate from the higher bands directly to n-space without a four minute interval, then the accuracy of translations would at least be equal to translating from the alpha band to n-space. But then it seems the problem with drift reasserts itself for the ship that drops down to n-space to refine the hyperlogs, when transiting back up into the iota or kappa band???

As I said during that particular discussion, I thought the four minute interval was more to protect frail humans instead of an actual requirement for the maneuver. If the former, then the MA's genetics should have solved the problem of nausea and a crash crash crash translation should be possible.

penny wrote:We simply do not know what amenities a spider-drive system might offer. We can speculate, but that is all. A spider-drive might deliver an even bigger “tax break” for traveling in hyper than our current administration.

I'm not sure how. Travel time in hyper is based on exactly 3 things and a spider drive (in and of itself) can only directly affect one of them and we know it affects it in a negative way.

From most to least impactful:
1. Velocity multiplier - based entirely on what bands you're traveling it. Basically the compression ratio of hyper. The streak drive helps a lot here because by getting up into the Kappa band it gives about 1.45x more multiplier than a ship would get in the Theta band -- but that's orthogonal to the propulsion method of a ship. So not a benefit of the spider drive; even though the MAlign would be stupid not to put that better generator on all their spider drive ships.

2. Particle shielding - A warship caps out at 0.6c within its hyper band due to particle shielding limits. If you could somehow improve the shielding enough to get up to 0.8c that can be as big a gain as going up a hyper band (at least in the higher bands were the band to band improvements are proportionately smaller). For example: Warship's get an effective 3000c in the Theta bands and 3600c in the Iota; but a ship able to managed 0.8c within the Theta bands would get an effective 4000c there.
But the drive system (wedge, sail, spider, reaction) doesn't alter how good your particle/rad shields are. (Now it's possible that the MAlign have also made some unmentioned breakthrough in particle shielding for their ships -- but such a breakthrough should apply equally to their wedge powered couriers as their spider powered ships.

3. Route - Ships can't always take the shortest distance course because of rogue waves and the like. It seems very unlikely that a spider drive could survive crossing on of those -- but if it could that might make certain trips much shorter by avoiding the longer detour. But it seems that most hyperspace journeys don't have than issue and so even such hypothetical capability wouldn't help the spider on most routes.

4. Acceleration - This is lease important because the vast majority of time in hyper is spent cruising at max velocity, so even massive improvements in acceleration yield pretty small reductions in travel time. Which is good for spider ships, as we know they accelerate slower and thus this aspect of their drive increases (rather than decreases) transit times.
A spider drive's safe sustained acceleration is 150g, while even old SDs pull 400g, and the latest RMN compensators seem to let SDs pull over 600g. (Also, a ship with compensator and sails can use a grav wave pull nearly 10x the acceleration it can under wedge - so a 600g ship cuts its 0 to .6c acceleration time from about 8.5 hours to about 50 minute -- which is great but still shaves less than 8 hours off a multi-day or multi-week trip). And it's also unclear how much, if any, benefit a spider ship might get from traveling in a grav wave.

So there doesn't seem to be any plausible way for the spider drive itself to give a bigger “tax break” for traveling in hyper.



I'll also note in passing that the books seem use "crash" translation not as one there the hyper-generator works faster but one in which the ship didn't slow slow its velocity before changing bands. So it saves you deceleration time, but doesn't seem to get you across each hyper wall any quicker.
But it also means the velocity bleed, while bleeding off the same percentage of velocity, has to bleed off vastly more total energy (resulting in a larger arrival flare and a more stressful ride for machinery and occupants.

honor Among Enemies wrote:A ship bled over ninety percent of its velocity as it broke each hyper-space wall in a downward translation, which could be a handy tactical maneuver. But crash translations were rough on personnel and systems, and merchant skippers preferred the gentler, safer stress of a low velocity translation. It not only allowed their crews to avoid the violent nausea crash translations induced but also reduced alpha node wear by a measurable percentage, and that made their employers' bookkeepers happy with them, too.

If that's right, and I think it is, then the reason Fuchien was asking about the possibility of a crash translation for the damaged Artemis wasn't because she needed the hyper generator to move them any faster (after all it'd seem pointless to wait several minutes under fire to find out if that was safe when even a normal translation would avoid the incoming salvos) but because she needed to know if she had to decelerate first (which would have let the pursuing Peep battlecruiser catch up and also given it time to pound the liner to scrap)

So a non-crash translation would seemingly involve flipping ship and spending some few hours shedding velocity before activating your hyper generator. Resulting in a more comfortable translation, lower machinery wear, and a smaller arrival flare; but also a lower residual velocity on arrival. (Though residual velocities are so low anyway that doesn't mater anywhere near as much as the extra time spend decelerating does)

penny wrote:Can a ship drop out of hyper from any band directly into n-space?

Jonathan_S wrote:Depends on what you mean by "directly".

The best description we have is one I alluded to in a recent post, the arrival of Honor's convoy to Grayson

So you don't need to stop in each band for the hyper generator to recharge; so in that sense it is direct.

But you do need to pass through each band (bleeding off velocity as you do so) on your way -- so if there was a ship within sensor range in any of those lower bands they'd see the convoy dropping through -- and if within weapons range could try to fire on it.

penny wrote:Your statement isn't clear. I was asking if a ship has to stop in each band on its way to n-space. You say that it does not have to stop. But text says there is a “layover” of four minutes. That is stopping in each band. I am thinking that it should not be possible for a ship to fire on another ship that is performing a crash translation directly to n-space without the four minute delay between bands.

Intuitively, the hyper generator should not need recharging inbetween transiting down from higher bands. I am assuming that since the streak drive needed an oversized hyper generator to “brute force” its way into the higher bands, that a lower band needs less “brute force” therefore logically, descending the bands should require less and less effort from the hyper generator. And since the streak drive employs an oversized generator anyway, the four minute interval between bands should not be necessary. Logically that is, which also is not written in stone.

--- skip ---

As I said during that particular discussion, I thought the four minute interval was more to protect frail humans instead of an actual requirement for the maneuver. If the former, then the MA's genetics should have solved the problem of nausea and a crash crash crash translation should be possible.

I do not understand Jonathan_S's statement that the four minutes are necessary, but it is not due to the hyper-generator recharging. So far as I know, it is precisely because the hyper-generator needs recharging and therefore an irreducible part of the transition process between hyperspace and normal space. Perhaps this is not a full recharge?

If the pauses were due to protecting "frail humans", then they could be shorter than the strict four minutes. Even one minute should be sufficient for that.

tlb wrote:I do not understand Jonathan_S's statement that the four minutes are necessary, but it is not due to the hyper-generator recharging. So far as I know, it is precisely because the hyper-generator needs recharging and therefore an irreducible part of the transition process between hyperspace and normal space. Perhaps this is not a full recharge?

If the pauses were due to protecting "frail humans", then they could be shorter than the strict four minutes. Even one minute should be sufficient for that.

I don't know if it's necessary -- I simply quoted to book where the convoy did take that long.

Though don't forget that the within a given names bands (Beta bands for example) there appear to be multiple different sub-bands (apparently all with slightly different velocity multipliers). And so the four minutes the text says the convoy took to cross the Gamma bands might have been because they had to drop through multiple of those sub-bands. But the text tells us almost nothing of those beyond a couple of hints.

But in the end we don't know why it took them four minutes, nor if it's possible to do that quicker. All we know is the text said in this one situation this is how long it took.


But what I was trying to point out by referring to that quote is that 4-minutes is far to quick to allow a hyper generator to fully recharge (that's more like half an hour) and so that time must have been due to something else.

Jonathan_S wrote:I don't know if it's necessary -- I simply quoted to book where the convoy did take that long.

Though don't forget that the within a given names bands (Beta bands for example) there appear to be multiple different sub-bands (apparently all with slightly different velocity multipliers). And so the four minutes the text says the convoy took to cross the Gamma bands might have been because they had to drop through multiple of those sub-bands. But the text tells us almost nothing of those beyond a couple of hints.

But in the end we don't know why it took them four minutes, nor if it's possible to do that quicker. All we know is the text said in this one situation this is how long it took.

But what I was trying to point out by referring to that quote is that 4-minutes is far to quick to allow a hyper generator to fully recharge (that's more like half an hour) and so that time must have been due to something else.

So it could be a partial recharge, we just do not know. Which is why we cannot just use intuition to say something must be the case.
At All Costs, Chapter 64:

And once their hyper generators finished cycling, they could always disappear into hyper if things looked like getting too hot anyway

Chapter 67:

It looked as if Kuzak had decided stopping him was more important than shooting at ships which could vanish into hyper any time they chose, once their hyper generators had finished cycling from their last translation.

Not that I am correct by any means, but I am unsure that I am making myself clear. Ascending the bands require assistance from the hyper generator, thus the hyper generator needs to be charged. The streak drive needs an oversized generator to “climb” into the higher bands. As an analogy, climbing a ladder that has many many rungs require a lot of work from our legs. But once we are at the top, getting off the ladder requires no effort at all. We can simply jump off. I am not saying it is as straightforward as that for descending bands, but each lower band should require less and less effort to pierce. Intuitively it holds water but I agree it is not written in stone.

Personally I think it is more a matter of concern for wear and tear on the ship -- or even worse, destroying the ship outright; along with what I imagine is some serious nausea from a multi-crash translation. If each successive translation requires input from a live body (cannot be automated) then there might need to be time for the astrogator(?) to recover from his nausea to think or see straight enough to input the commands. I seriously doubt that I could swipe left or right on my smartphone if I am seriously puking up my “family jewels.”

penny wrote:Not that I am correct by any means, but I am unsure that I am making myself clear. Ascending the bands require assistance from the hyper generator, thus the hyper generator needs to be charged. The streak drive needs an oversized generator to “climb” into the higher bands. As an analogy, climbing a ladder that has many many rungs require a lot of work from our legs. But once we are at the top, getting off the ladder requires no effort at all. We can simply jump off. I am not saying it is as straightforward as that for descending bands, but each lower band should require less and less effort to pierce. Intuitively it holds water but I agree it is not written in stone.

Personally I think it is more a matter of concern for wear and tear on the ship -- or even worse, destroying the ship outright; along with what I imagine is some serious nausea from a multi-crash translation. If each successive translation requires input from a live body (cannot be automated) then there might need to be time for the astrogator(?) to recover from his nausea to think or see straight enough to input the commands.

So far as I know going through a "wall" requires the same effort, no matter in which direction the transition is being made. It is possible that effort gets greater as the bands get higher, but it is NOT like jumping off a ladder.

There is no reason that the transitions could not be under computer control, just the same as a fusion reactor requires computer control (so there should never be a case where the reactor lost containment because the operator was too slow, unless the software was inadequate).

penny wrote:Personally I think it is more a matter of concern for wear and tear on the ship -- or even worse, destroying the ship outright; along with what I imagine is some serious nausea from a multi-crash translation.

I would note that since a crash translation appears to be a mater of the ship's starting velocity that a "multi-crash" translation would actually get less and less crashy each wall you translated through.

I'll do this from the Iota bands because RFC hasn't shared the velocity bleed-off values for Kappa, so take a streak-drive equipped ship screaming along at 0.6c in the Iota bands and starts a crash translation down to normal space. Here's its resulting velocity in each set of bands along the way.
Iota bands: 0.6c (179,875 KPS)
48% velocity bleed off dropped through the Iota wall
Theta bands: 0.312c (93,535 KPS)
52% velocity bleed off dropping through the Theta wall
Eta bands: 0.14976c (44,897 KPS)
56% velocity bleed off dropping through the Eta wall
Zeta bands: 0.065c (19,755 KPS)
61% velocity bleed off dropping through the Zeta wall
Epsilon bands: 0.025c (7,704 KPS)
66% velocity bleed off dropping through the Epsilon wall
Delta bands: 0.008c (2,619 KPS)
72% velocity bleed off dropping through the Delta wall
Gamma bands: 0.002c (733 KPS)
78% velocity bleed off dropping through the Gamma wall
Beta bands: 161 KPS
85% velocity bleed off dropping through the Beta wall
Alpha bands: 24 KPS
92% velocity bleed off dropping through the Alpha wall
Normal space: 2 KPS

By the time you've crashed through the first two or three walls you've lost so much velocity from the bleed-off effect that the remaining translations shouldn't be considered crash ones.