Captain Zilwicki's options in SVW?

ThinksMarkedly wrote:

Jonathan_S wrote:Technically incorrect; Rob S Pierre hadn't yet launched his little coup to create the People's Republic; and hence they weren't yet the People's Republic of Haven Navy. So the nickname 'Peeps' is technically premature for this time period.

Oops, yes they were. They'd been the People's Republic of Haven and the People's Navy for a century and a half, since the Constitutional Convention of 1750, which is about 70 T-years after the Economic Bill of Rights. Hereditary President Harris was its chief of state. They'd been known as "peeps" for that long -- the slang name couldn't have caught on if they'd been that for just 10 T-years.

Rob S Pierre's coup created the Committee of Public Safety, but didn't change the republic's official name.

Oops indeed. Thanks for correcting me on that.

cthia wrote:

That is the only possibility I could come up with as well, that Peep sensors were locked onto their sails. But at that same point - where the convoy's trailing destroyer first caught sight of the Peeps - interception was still beyond two hours.

Therefore, your post still doesn't explain why the convoy's CLs couldn't detect the sails or ships of six Peep CAs while passing right by them. Since sails so easily burn through the disturbance in hyper at greater than two hrs away.

Now, textev does say the Peep force was using hellish ECM to thwart the sensors of the convoy's lesser capable trailing destroyer. But if it was also effective enough to defeat the sensors of the convoy's CLs while passing right by them, then the LDs are going to have a field day.[/quote]
We know with wedges, and I assume with sail, that the more power they're pulling the stronger their emissions and the easier they are to see.

The Peeps were apparently holding stationary, so their sails would have been drawing the minimal possible power when the convoy overflew them. But the convoy would have been sailing by at the max speed of the freighers (0.5c in hyper), so their sails would have been far, far, more visible than those of the cruisers lying in ambush.

But when the cruisers started overhauling them they'd be working up to their max velocity (0.6c in hyper) and so their sails would have been burning bright on grav sensors; despite the best their ECM could do.


If the freighters cut power to their sails to the minimum they'd become far less visible - but since the hostile cruisers were already tracking they'd know the course the freighters and with sails at minimum power levels you can't change your current trajectory much. So the cruisers could just close to where the freighters would have to be and start hunting (and at close range they can use radar and EM passive sensors, not just grav detection - though even minimal power sails can probably be detected at beyond effective radar range; unless you've got ECM to help hide them, which freighters wouldn't).

And while the freighters could gain a short time to maneuver unobserved if they dropped out of hyper, or even to a lower band, it wouldn't be long before the cruisers followed them - and if the freighters were still accelerating when the cruisers appear then they'd be giving away their position (and new course). But if they don't accelerate to change course the cruisers can easily calculate where their known velocity would carry them. And don't forget how much velocity you lose changing hyper bands. That'd make it even easier for the cruisers to use their superior acceleration to search for the now even slower freighter.

Jonathan_S wrote:

cthia wrote:That is the only possibility I could come up with as well, that Peep sensors were locked onto their sails. But at that same point - where the convoy's trailing destroyer first caught sight of the Peeps - interception was still beyond two hours.

Therefore, your post still doesn't explain why the convoy's CLs couldn't detect the sails or ships of six Peep CAs while passing right by them. Since sails so easily burn through the disturbance in hyper at greater than two hrs away.

Now, textev does say the Peep force was using hellish ECM to thwart the sensors of the convoy's lesser capable trailing destroyer. But if it was also effective enough to defeat the sensors of the convoy's CLs while passing right by them, then the LDs are going to have a field day.

We know with wedges, and I assume with sail, that the more power they're pulling the stronger their emissions and the easier they are to see.

The Peeps were apparently holding stationary, so their sails would have been drawing the minimal possible power when the convoy overflew them. But the convoy would have been sailing by at the max speed of the freighers (0.5c in hyper), so their sails would have been far, far, more visible than those of the cruisers lying in ambush.

But when the cruisers started overhauling them they'd be working up to their max velocity (0.6c in hyper) and so their sails would have been burning bright on grav sensors; despite the best their ECM could do.


If the freighters cut power to their sails to the minimum they'd become far less visible - but since the hostile cruisers were already tracking they'd know the course the freighters and with sails at minimum power levels you can't change your current trajectory much. So the cruisers could just close to where the freighters would have to be and start hunting (and at close range they can use radar and EM passive sensors, not just grav detection - though even minimal power sails can probably be detected at beyond effective radar range; unless you've got ECM to help hide them, which freighters wouldn't).

And while the freighters could gain a short time to maneuver unobserved if they dropped out of hyper, or even to a lower band, it wouldn't be long before the cruisers followed them - and if the freighters were still accelerating when the cruisers appear then they'd be giving away their position (and new course). But if they don't accelerate to change course the cruisers can easily calculate where their known velocity would carry them. And don't forget how much velocity you lose changing hyper bands. That'd make it even easier for the cruisers to use their superior acceleration to search for the now even slower freighter.

Thanks Jonathan. As far as I am concerned, it puts the monkey on my back at every waking moment at rest. I should have brought it up years ago. Again, thanks.

Jonathan_S wrote:And while the freighters could gain a short time to maneuver unobserved if they dropped out of hyper, or even to a lower band, it wouldn't be long before the cruisers followed them - and if the freighters were still accelerating when the cruisers appear then they'd be giving away their position (and new course). But if they don't accelerate to change course the cruisers can easily calculate where their known velocity would carry them. And don't forget how much velocity you lose changing hyper bands. That'd make it even easier for the cruisers to use their superior acceleration to search for the now even slower freighter.

That's even assuming the freighters are able to do a crash translation. I assume "running away from the enemy" is close to the top of the list of "reasons to do a crash translation (if it helps)," so they'd be willing to do it. The question is: were they able to do that? Those freighters didn't mount military hyper generators. Since they were in delta, they'd need a minimum of 30 minutes to start the sequence to drop down to gamma; if each of the next 3 transitions takes an additional 10 minutes, they'll have needed 60 minutes to reach n-space. Meanwhile, the PN CAs are travelling in delta, so they actually close the distance much more quickly than the 2 hours they originally had. And those can do crash translations.

A tactic that has just occurred to me: don't crash to n-space, but transition only to gamma. Assuming the grav wave was also there on this band, the freighters should be able to re-accelerate quickly using sails, since that does not depend on the impeller strength, just on the wave itself. So the transition should allow the ships to change direction unobserved. The problem is I don't think this helps for the same reason as above: dropping down means your pursuers are actually overhauling you much more quickly. They can reach the point where you transitioned (or close enough) before dropping to gamma, then they'll be that much closer when they try to reacquire you.

ThinksMarkedly wrote:

Jonathan_S wrote:And while the freighters could gain a short time to maneuver unobserved if they dropped out of hyper, or even to a lower band, it wouldn't be long before the cruisers followed them - and if the freighters were still accelerating when the cruisers appear then they'd be giving away their position (and new course). But if they don't accelerate to change course the cruisers can easily calculate where their known velocity would carry them. And don't forget how much velocity you lose changing hyper bands. That'd make it even easier for the cruisers to use their superior acceleration to search for the now even slower freighter.

That's even assuming the freighters are able to do a crash translation. I assume "running away from the enemy" is close to the top of the list of "reasons to do a crash translation (if it helps)," so they'd be willing to do it. The question is: were they able to do that? Those freighters didn't mount military hyper generators. Since they were in delta, they'd need a minimum of 30 minutes to start the sequence to drop down to gamma; if each of the next 3 transitions takes an additional 10 minutes, they'll have needed 60 minutes to reach n-space. Meanwhile, the PN CAs are travelling in delta, so they actually close the distance much more quickly than the 2 hours they originally had. And those can do crash translations.

A tactic that has just occurred to me: don't crash to n-space, but transition only to gamma. Assuming the grav wave was also there on this band, the freighters should be able to re-accelerate quickly using sails, since that does not depend on the impeller strength, just on the wave itself. So the transition should allow the ships to change direction unobserved. The problem is I don't think this helps for the same reason as above: dropping down means your pursuers are actually overhauling you much more quickly. They can reach the point where you transitioned (or close enough) before dropping to gamma, then they'll be that much closer when they try to reacquire you.

Technically acceleration with sails is linked to impeller strength, as the appendix to Short Victorious War says "a ship under Warshawski sail can pull almost ten times the acceleration it could under impeller drive."

So cruisers should still have an acceleration advantage, even though the freighter would probably be pulling north of 3000 gees. (And due to their superior rad shielding the cruisers have a higher maximum speed too)

But yes - dropping down seems very likely to let the pursuers catch up.




In theory they could try to do the same thing against a target in the Delta band by first climbing into the Epsilon bands - but the hyper generator charge time you'd presumably need to jump and and back down would let the target change course or drop bands while out of your sight. So that tactic seems like it'd only be useful if you had enough force you could detach a couple of ships to try to make themselves a roadblock 20 - 30 minute later after they can drop back down. The bulk of your ships maintaining the pursuit keeps the freighters from playing too many games.

OTOH I still doubt that's much used as the convoy or its escort might try to take advantage of the interval when your numbers are temporarily reduced -- either scattering or turning to engage your temporarily weakened force.

But if they drop from Delta into Gamma then you're only a single transition behind them, not the pair it would take to try to overfly them using the Epsilon bands.

ThinksMarkedly wrote:

Jonathan_S wrote:And while the freighters could gain a short time to maneuver unobserved if they dropped out of hyper, or even to a lower band, it wouldn't be long before the cruisers followed them - and if the freighters were still accelerating when the cruisers appear then they'd be giving away their position (and new course). But if they don't accelerate to change course the cruisers can easily calculate where their known velocity would carry them. And don't forget how much velocity you lose changing hyper bands. That'd make it even easier for the cruisers to use their superior acceleration to search for the now even slower freighter.

That's even assuming the freighters are able to do a crash translation. I assume "running away from the enemy" is close to the top of the list of "reasons to do a crash translation (if it helps)," so they'd be willing to do it. The question is: were they able to do that? Those freighters didn't mount military hyper generators. Since they were in delta, they'd need a minimum of 30 minutes to start the sequence to drop down to gamma; if each of the next 3 transitions takes an additional 10 minutes, they'll have needed 60 minutes to reach n-space. Meanwhile, the PN CAs are travelling in delta, so they actually close the distance much more quickly than the 2 hours they originally had. And those can do crash translations.

A tactic that has just occurred to me: don't crash to n-space, but transition only to gamma. Assuming the grav wave was also there on this band, the freighters should be able to re-accelerate quickly using sails, since that does not depend on the impeller strength, just on the wave itself. So the transition should allow the ships to change direction unobserved. The problem is I don't think this helps for the same reason as above: dropping down means your pursuers are actually overhauling you much more quickly. They can reach the point where you transitioned (or close enough) before dropping to gamma, then they'll be that much closer when they try to reacquire you.

Interesting attempt ThinksMarkedly. The freighters could drop down a band and immediately come to a full stop allowing the Peeps to pass right by them without seeing them. The same tactic that was used on them. Tit for tat. And if the Peeps miss them, they won't know where they've gone.

The problem would be how fast they can kill accel. But perhaps there is a yet unused sort of "crash translation" in a grav wave which uses negative sails to quickly stop. Maybe negatively pulsing forward and rear sails on and off would act like an emergency breaking? Of course, that could destroy the ships.

Can thrusters be used in grav waves?

Can a ship flip end to end in hyper? If so, to what effect if it uses negative acceleration as if tacking into the wind.

cthia wrote:Interesting attempt ThinksMarkedly. The freighters could drop down a band and immediately come to a full stop allowing the Peeps to pass right by them without seeing them. The same tactic that was used on them. Tit for tat. And if the Peeps miss them, they won't know where they've gone.

The problem would be how fast they can kill accel. But perhaps there is a yet unused sort of "crash translation" in a grav wave which uses negative sails to quickly stop. Maybe negatively pulsing forward and rear sails on and off would act like an emergency breaking? Of course, that could destroy the ships.

Can thrusters be used in grav waves?

Can a ship flip end to end in hyper? If so, to what effect if it uses negative acceleration as if tacking into the wind.

Simply dropping from Delta to Gamma will eliminate 78% of the ship's velocity in the "Translation Bleed-Off" (if you went down to the Beta bands that's would blead off another 85% of what's left). So a freighter translating down to the Beta bands would be down to about 4,950 kps (assuming its civilian grade hyper generator could take the stresses of that crash translation) - in a grav wave they could probably kill that velocity in another 5 minutes or so of hard acceleration.

OTOH the cruisers will see the transition, and they know the ship's course, velocity, likely acceleration, and the transition bleed off rates for each hyper band. They'll have a very accurate estimate of the area of space in each band a fleeing freighter could put itself in. All they need to do is fly close enough to scan that fairly small volume with their radars in order to find any freighter that's trying to hide (and that's assuming that even minimal power sails are detectable from further distance than that).

Of course if the ship drops to a band without a grav wave, or even to normal space, then it can drop its drive entirely, so radar or passive EM sensors become the best bet for finding it. But correspondingly its acceleration drops about tenfold without the grav wave available to boost it.


And yes, the cruisers start out a few hours behind. But once the freighter drops to even the Beta bands the difference in velocity multiplication cuts the time to catch up by more than half [edit: plus they'll have lost most of their velocity and the cruisers won't until they transition; increasing the overtake advantage of the higher hype band] - so they'll be able to catch up that much faster and start their search for the freighter. It'd need a lot of luck to hide from a batch of cruisers that have a very good idea of how far it could have gotten.

ThinksMarkedly wrote:That's even assuming the freighters are able to do a crash translation. I assume "running away from the enemy" is close to the top of the list of "reasons to do a crash translation (if it helps)," so they'd be willing to do it. The question is: were they able to do that? Those freighters didn't mount military hyper generators. Since they were in delta, they'd need a minimum of 30 minutes to start the sequence to drop down to gamma; if each of the next 3 transitions takes an additional 10 minutes, they'll have needed 60 minutes to reach n-space. Meanwhile, the PN CAs are travelling in delta, so they actually close the distance much more quickly than the 2 hours they originally had. And those can do crash translations.

Short answer is probably yes, even civilian freighters CAN crash translate, they just don't because overstressing systems takes hundreds or thousands of hours off the design lifetime and risks component failures. But if you're about to be blown to plasma you really have nothing to lose by trying.

We have at least one example of a freighter crash translating in SVW, where the single survivor of a convoy crashes into Yeltsin but is picked off by the pursuing Peeps before anyone can intervene.

Jonathan_S wrote:Technically acceleration with sails is linked to impeller strength, as the appendix to Short Victorious War says "a ship under Warshawski sail can pull almost ten times the acceleration it could under impeller drive."

So cruisers should still have an acceleration advantage, even though the freighter would probably be pulling north of 3000 gees. (And due to their superior rad shielding the cruisers have a higher maximum speed too)

Both impeller drive and sail drive are primarily limited by inertial compensator efficiency. For the most part raw impeller power is the limiting factor only when a ship has lost nodes to combat damage or some other type of component failure. Freighters can accelerate faster in waves but warships would still hold the same comparative advantage, all else being equal. The rare times it would matter is something like the Peep Q ship escaping from Basilisk, where a few minutes accelerating at 10x speed would have let them get out of sensor range of Fearless if she tried to follow them.

cthia wrote:Interesting attempt ThinksMarkedly. The freighters could drop down a band and immediately come to a full stop allowing the Peeps to pass right by them without seeing them. The same tactic that was used on them. Tit for tat. And if the Peeps miss them, they won't know where they've gone.

The problem would be how fast they can kill accel. But perhaps there is a yet unused sort of "crash translation" in a grav wave which uses negative sails to quickly stop. Maybe negatively pulsing forward and rear sails on and off would act like an emergency breaking? Of course, that could destroy the ships.

Can thrusters be used in grav waves?

Can a ship flip end to end in hyper? If so, to what effect if it uses negative acceleration as if tacking into the wind.

As above, the limiting factor is the compensator, not sail power (or rather, sails and impellers are designed around how much the ship can compensate for, usually with some redundancy for warships to lose a beta node and still maintain impeller power).

Sails can and do use "negative grab factor" on the sails to decelerate in waves. As far as we know flipping is possible but not necessary; perhaps it was necessary at one point but is no longer.

Thrusters should be able to be used in waves, but why would they outside of a ship losing a sail trying desperately to get out of the wave before they are destroyed by turbulence? Thruster acceleration is far lower than impeller acceleration and wouldn't even compare to sail power. It's possible that the ship's compensator would actually work to counteract thruster acceleration in that situation, since it's dumping to the wave rather than the ship's impeller wedge, but fuel constraints would still limit the total burn a ship could produce.

Galactic Sapper wrote:Sails can and do use "negative grab factor" on the sails to decelerate in waves. As far as we know flipping is possible but not necessary; perhaps it was necessary at one point but is no longer.

While not quite flipping 180 as is done outside a wave, there was a long time (looks like nearly 5 centuries) between the invention of the sail (1273 PD) and it getting refined to the point of pulling off "negative grab factor".

Now, most of the time you're destination wouldn't be within the 'wave and so there's no need to slow down just sail out of the wave, switch to impellers, and make the last 'cross country' trek to your destination. As you're using your wedge at that point you would do a 180 flip to slow down and avoid a crash translation.

But in the event you were going to a system that sat squarely within the wave (or at least the wave you were taking crossed that system, even if the wave didn't extend all the way down to the Alpha bands) you would want to slow, while still within the wave, prior to translation. If you'd been heading down wave you'd presumably need to come about as much as you could and start tacking against the wave to kill your velocity - so maybe a 130ish degree turn rather than the full 180 flip (though as sails improve and you can make tighter tacks you'd be turning correspondingly further). And similarly if you'd been tacking up wave you don't need a full 180 since you'd stop once you were pointed straight down wave (as I'm assuming that's your most efficient sailing angle)

Here's the full passage talking about tacking and the later improvements that negated the need for it.

More Than Honor wrote:In addition, it was possible for a Warshawski Sail ship to "reach" across a wave (which might be thought of as sailing with a "quartering breeze") at angles of up to about 60° before the sails began losing drive and up to approximately 85° before all drive was lost. By the same token, a hypership could sail "close-hauled," or into a grav wave, at approach angles of 45°. At angles above 45°, it was necessary to "tack into the wave," which naturally meant that return passages would be slower than outgoing passages through the same region of prevailing grav waves. Thus the old "windjammer" technology of Earth's seas had reemerged in the interstellar age, transmuted into the intricacies of hyper-space and FTL travel. By 1750 pd, however, sail tuners had been upgraded to a point which permitted the "grab factor" of a sail to be manipulated with far more sophistication than Dr. Warshawski's original technology had permitted. Indeed, it became possible to create a negative grab factor which, in effect, permitted a starship to sail directly "into the wind," although with a marginally greater danger of sail failure.

Oh, and don't forget that crash translations aren't just hard on the systems. One was described in EoH when the 1st Peep force crashed into Basilisk and it mentioned that even trained military crew might be totally incapacitated for a couple minutes by the effects of a crash translation.