What happens in Hyperspace near a Star?

tlb wrote:In the battle of Sidemore, the ship that transitioned to call in the force waiting in hyper was noted as transitioning into hyper without alerting the Havenite force. Doesn't that mean that the sails cannot be active before the transition? I assume that they can be detected the same as a wedge. Or is that incorrect?

Not sure. The sails are 200 km in radius but we don't know whether they are visible in n-space like wedges are. We do know from every single WH transition that where we hear the ship captain's POV that the acceleration drops by half when the forward impellers transition to foresail. Since the sails are not generating force until they cross into the threshold of the WH, it's possible they are not detectable beyond very short range. From those WH transition descriptions, we hear how they dissipate energy after the transition, but not about energy before.

Even if they do produce a lot of energy, there's a big problem, which is time to detection: I presume sails are not detectable by FTL means, like wedges are. We know ships transitioning into a system are first detected by their wedges snapping on, before the energy of the transition is detected. Even if the ship was producing a pair of 125000 km² circles of radiation emission, from the distance Tourville's ships were, they would not get the lightspeed signal in time to make a difference to the course of battle. Also note sails are basically 2D constructs, even if they have a slant. So the ship could orient itself so the sails are in profile to the attacking force, diminishing the surface of emission.

The other possibility is that they are detectable by FTL means, in which case there has to be another mechanism that allows an intact ship to transition without sails, but flip them on in sufficient time before getting destroyed. If that idea of a hypergenerator bubble is correct and considering we know it takes time for the hypergenerator to transition the ship after it's turned on, it could be that there's sufficient time after the transition before the bubble dissipates to turn the sails on.

I don't think we know enough.

ThinksMarkedly wrote:Even if they do produce a lot of energy, there's a big problem, which is time to detection: I presume sails are not detectable by FTL means, like wedges are. We know ships transitioning into a system are first detected by their wedges snapping on, before the energy of the transition is detected.

A sail is basically a wedge oriented a different direction, so it should be as detectable as a wedge with similar power settings.

And how do we "know" transitioning ships are detected by their wedge and not their transition signature? Both are gravitic events propagating along the Alpha wall interface at 62 times light speed. Both signals would arrive simultaneously, or with whatever delay is between translation and powering the wedge.

The other possibility is that they are detectable by FTL means, in which case there has to be another mechanism that allows an intact ship to transition without sails, but flip them on in sufficient time before getting destroyed. If that idea of a hypergenerator bubble is correct and considering we know it takes time for the hypergenerator to transition the ship after it's turned on, it could be that there's sufficient time after the transition before the bubble dissipates to turn the sails on.

I don't think we know enough.

We do know that a ship without sails isn't instantly destroyed in a grav wave. A ship with a wedge up is destroyed instantly due to interference between the wave and the nodes generating the wedge, but a ship with neither wedge nor sails that isn't moving can survive basically indefinitely, and a moving ship without sails can survive until it hits a patch of turbulence (grav sheer) strong enough to rip the ship apart. We saw this in SVW when the Havenite ships that lost sails against Captain Zilwiki's convoy escort squadron survived to be towed clear of the wave by their undamaged peers.

A ship surviving a few seconds after translation without sails- especially as low speeds - is perfectly reasonable.

Also, I've never understood the whole "acceleration drops to half" bit of raising the fore sail. Each impeller ring generates a full size wedge, one inside the other, which is why a ship retains half acceleration when they lose a ring (and why missiles and drones only need one ring). Surely this means by having the fore sail and a wedge up at the same time means the two would be intersecting and interfering with each other!

Galactic Sapper wrote:We do know that a ship without sails isn't instantly destroyed in a grav wave. A ship with a wedge up is destroyed instantly due to interference between the wave and the nodes generating the wedge, but a ship with neither wedge nor sails that isn't moving can survive basically indefinitely, and a moving ship without sails can survive until it hits a patch of turbulence (grav sheer) strong enough to rip the ship apart. We saw this in SVW when the Havenite ships that lost sails against Captain Zilwiki's convoy escort squadron survived to be towed clear of the wave by their undamaged peers.

A ship surviving a few seconds after translation without sails- especially as low speeds - is perfectly reasonable.

Also, I've never understood the whole "acceleration drops to half" bit of raising the fore sail. Each impeller ring generates a full size wedge, one inside the other, which is why a ship retains half acceleration when they lose a ring (and why missiles and drones only need one ring). Surely this means by having the fore sail and a wedge up at the same time means the two would be intersecting and interfering with each other!

We do know that a ship with damaged alpha nodes is effectively stranded in n-space and will not transition to alpha. It might be an overabundance of caution, but if the nodes were repairable, I'd expect the skipper to make the transition and give engineering more time to fix things. While in alpha, a ship cannot be reached by missiles launched from n-space and the regular battle geometry has defenders coming in from deep inside the hyperlimit, so it will take them time to reach it so they can transition. And if the star system exists in a grav wave, missiles can't be fired in alpha either. So escaping to alpha should have been a very common tactical solution, but we haven't heard about that.

I didn't understand your point about the half acceleration. You said that the acceleration drops to half when they lose a ring -- this is effectively what happens when said ring becomes a foresail. So shouldn't the acceleration drop by half the same way?

I don't know about the acceleration being halved when they rig the foresail, but I do know that the wedge-strength is halved.

ThinksMarkedly wrote:We do know that a ship with damaged alpha nodes is effectively stranded in n-space and will not transition to alpha. It might be an overabundance of caution, but if the nodes were repairable, I'd expect the skipper to make the transition and give engineering more time to fix things. While in alpha, a ship cannot be reached by missiles launched from n-space and the regular battle geometry has defenders coming in from deep inside the hyperlimit, so it will take them time to reach it so they can transition. And if the star system exists in a grav wave, missiles can't be fired in alpha either. So escaping to alpha should have been a very common tactical solution, but we haven't heard about that.

That's not entirely true. A ship with a damaged alpha node is only stranded in n-space if they system is in a grav wave. A ship without a sail can escape into hyper otherwise, but generally doesn't. In most cases a ship that loses an entire ring can't stay ahead of the defending fleet and gets destroyed or pounded into surrendering because they can't run away fast enough, not because they can't run away at all. Individual damaged nodes are more survivable because they slow the ship less than losing a full ring.

I'm fairly sure we've seen examples of ships getting away with damaged alpha nodes, but I can't remember any off the top of my head. Perhaps some of Second Fleet escaping Marsh (close to but not in a grav wave)? The Fearless chasing the Sirius in OBS certainly qualifies - the reason Harringon had to stop the Sirius before she got to hyper wasn't because Fearless couldn't transition but because Sirius would be in the wave and Fearless couldn't continue the chase in the wave. I'm sure there have been others as well.

Admittedly, RFC does seem to have a pretty high percentage of systems located in grav waves to accentuate the "fight to the death because we can't run away" factor.

I didn't understand your point about the half acceleration. You said that the acceleration drops to half when they lose a ring -- this is effectively what happens when said ring becomes a foresail. So shouldn't the acceleration drop by half the same way?

The point is that it should drop to zero. Each ring forms a full length wedge, not the forward half and aft half respectively. So when one ring is generating a sail and the other is generating a wedge you have two stress bands intersecting and interfering with each other. In every other circumstance that makes the nodes - and very shortly thereafter, the entire ship - explosively disassemble themselves. A ship shouldn't be able to survive having both up at once.

Galactic Sapper wrote:The point is that it should drop to zero. Each ring forms a full length wedge, not the forward half and aft half respectively. So when one ring is generating a sail and the other is generating a wedge you have two stress bands intersecting and interfering with each other. In every other circumstance that makes the nodes - and very shortly thereafter, the entire ship - explosively disassemble themselves. A ship shouldn't be able to survive having both up at once.

That's a very good point. The sails are generated at the fore and aft of the ship, not 90 km ahead and behind it. So a foresail, as we've heard the descriptions of the transitions, effectively intersects the ceiling and floor of the wedge generated by the after ring.

But we know ships still accelerate and don't get destroyed, so we must look for an explanation.

Hypothesis 1: wedge and sail of properly tuned rings that do work in a pair don't destructively interfere with each other, despite intersecting. Prior art: sidewalls, bowwalls, and sternwalls do intersect the floor and ceiling, and though much weaker, don't destabilise each other.

Hypothesis 2: when the fore ring switches to sail, the geometry of the wedge generated by the after ring changes, such that the floor and ceiling are much further from the ship, allowing the sail to exist within it like an incomplete bow wall. The geometry change could explain the drop in acceleration.

I've got a 3rd hypothesis too.

kzt wrote:I've got a 3rd hypothesis too.

Are you going to share it?

ThinksMarkedly wrote:

Galactic Sapper wrote:The point is that it should drop to zero. Each ring forms a full length wedge, not the forward half and aft half respectively. So when one ring is generating a sail and the other is generating a wedge you have two stress bands intersecting and interfering with each other. In every other circumstance that makes the nodes - and very shortly thereafter, the entire ship - explosively disassemble themselves. A ship shouldn't be able to survive having both up at once.

That's a very good point. The sails are generated at the fore and aft of the ship, not 90 km ahead and behind it. So a foresail, as we've heard the descriptions of the transitions, effectively intersects the ceiling and floor of the wedge generated by the after ring.

But we know ships still accelerate and don't get destroyed, so we must look for an explanation.

Hypothesis 1: wedge and sail of properly tuned rings that do work in a pair don't destructively interfere with each other, despite intersecting. Prior art: sidewalls, bowwalls, and sternwalls do intersect the floor and ceiling, and though much weaker, don't destabilise each other.

Hypothesis 2: when the fore ring switches to sail, the geometry of the wedge generated by the after ring changes, such that the floor and ceiling are much further from the ship, allowing the sail to exist within it like an incomplete bow wall. The geometry change could explain the drop in acceleration.

My reasoning for why raising a sail with the wedge up doesn't destroy the ship is quite simple:

Wedges are artificial gravity waves

Sails are designed to interface safely with gravity waves

Why would interfacing with a far smaller, weaker, and more controlled artificial gravity wave be a problem for a Sail?

ThinksMarkedly wrote:

kzt wrote:I've got a 3rd hypothesis too.

Are you going to share it?

It's 4 letters and is brought to us by the letter 'P'.