?

tlb wrote:Clearly you say the wedge start-up has an effect on the hull shape and that is the result of both Alpha and Beta nodes. So the sail might not affect hull shape (except for the requirement to be at the ends), but the Alpha nodes will still have an effect on the overall shape.

We do not think a fort has a compensator. So is it the compensator that has most effect on the ship shape (along with wedge start-up effects)?

For me, yes, modulo of course the start-up effects.

But forts have bubblewalls, which dictate the shape in other ways. And spheres have the best volume/surface ratio anyway.

tlb wrote:We do not think a fort has a compensator. So is it the compensator that has most effect on the ship shape (along with wedge start-up effects)?

Well Pinnaces definitely have compensators - but their hull shape (with those variable geometry wings, and atmospheric engine, sticking off sides and vertical tail(s) for atmospheric stability and control sticking up) doesn't follow the tapered cylinder null form of a starship. And, like a missile, they're drawn as having a single ring of impellers almost at their very aft end (for the pinnace just behind the engines; just in front of the horizontal and vertical atmospheric control surfaces).

And I don't think compensator fields have that taper and flare back out profile of a warship hull with its hammerhead. So the taper is probably forced by the wedge issues; while the largely cylindrical profile (in that the beam and draft are quite similar - and no odd structures sticking way off any side) is probably driven by the compensator.

(But again, pinnaces somehow get away with fairly large protuberances off their sides; and at least the latest ones are very quick under impeller; implying that they aren't slowed much, if at all, by their odd shape)

Jonathan_S wrote:Well Pinnaces definitely have compensators - but their hull shape (with those variable geometry wings, and atmospheric engine, sticking off sides and vertical tail(s) for atmospheric stability and control sticking up) doesn't follow the tapered cylinder null form of a starship. And, like a missile, they're drawn as having a single ring of impellers almost at their very aft end (for the pinnace just behind the engines; just in front of the horizontal and vertical atmospheric control surfaces).

And don't forget the two sloops, HMS Phobos and HMS Deimos, that were half the battlecruiser HMS Mars and were probably in the 70-90k tonne range. They did have compensators but a single ring.

But nothing tells us that the compensators are co-located with the rings. All we know is that they use the wedge's gravity sump to compensate. They could be an array distributed throughout the ship, so extending 100-150 m ahead of the ring might be no problem.

tlb wrote:We do not think a fort has a compensator. So is it the compensator that has most effect on the ship shape (along with wedge start-up effects)?

Why do we think that? They're still capable of moving under a wedge at ~50g, right? That's not particularly survivable for the crew. Also remember that forts have tonnage to spare, so including a compensator isn't that big of a deal. They also include both spherical and standard sidewalls for the same reason. For ships the tonnage difference makes the spherical sidewall impractical but forts have fewer size restrictions.

They could use the same grav plate compensation Honor used under reaction thrusters at Cerberus but that would have significant negative effects on crew efficiency while they were moving.

ThinksMarkedly wrote:But nothing tells us that the compensators are co-located with the rings. All we know is that they use the wedge's gravity sump to compensate. They could be an array distributed throughout the ship, so extending 100-150 m ahead of the ring might be no problem.

Evidence seems to suggest the compensator is a single unit mounted somewhat centrally similar to the hyper generator. There's never been an incident of a partial compensator failure, where say the bow of a ship failed but the crew in the stern survived. It's always all-or-nothing and can result from relatively minor damage to the ship, such as Kusak's flagship in BoM.

Evidence also suggests it's impossible or at least highly impractical to have any sort of redundancy in the system. If having multiple units provided some sort of protection against the all-or-nothing failure of such a vital system, warships would do it. Even being split fore-and-aft would mean half the crew would survive and be able to continue fighting the ship with remote systems. This doesn't happen, so we have to assume it's a single unit covering the entire ship.

Forts do not have compensators. They rely on grav plates to reduce the felt acceleration, but that limits them to 100-150 Gs

Duckk wrote:Forts do not have compensators. They rely on grav plates to reduce the felt acceleration, but that limits them to 100-150 Gs

To add, using a compensator over the tonnage ceiling would reduce acceleration to zero. (or a negative number ) So it's not a choice that forts don't have compensators - they simply can't.

Compensators don’t reduce acceleration (and they certainly don’t add to felt forces). You could put a compensator on a 20 million ton fort, it’s just very pointless to do so since it wouldn’t reduce the felt forces above and beyond anything the grav plates already can do.

Galactic Sapper wrote:They could use the same grav plate compensation Honor used under reaction thrusters at Cerberus but that would have significant negative effects on crew efficiency while they were moving.

Depends on how fast they're moving. Yes, at 150g the crew is subjected to 5g which will have a negative effect on their efficiency. But IIRC the grav plate's effects are somewhat non-linear and below 50 g I seem to recall that they can hold the felt acceleration to 1g. (And even in the worst case, if their 30x reduction applied linearly, they do could so a 30g and below)

So as long as the forts stick to well under 100 g of acceleration there shouldn't be much, if any, impact on crew efficiency. (And probably not coincidentally we're told that they're restricted to well under 100g of acceleration)

Theemile wrote:

Duckk wrote:Forts do not have compensators. They rely on grav plates to reduce the felt acceleration, but that limits them to 100-150 Gs

To add, using a compensator over the tonnage ceiling would reduce acceleration to zero. (or a negative number ) So it's not a choice that forts don't have compensators - they simply can't.

A negative acceleration simply denotes accel in the opposite direction. A Fort is backing up then. Retreating. LOL

Redundancy in compensator design isn't practical because it would still be subject to the technology. Technology operates on a time factor. Any time it would take for the auxillary system to kick in would be way too much.

Jonathan_S wrote:Depends on how fast they're moving. Yes, at 150g the crew is subjected to 5g which will have a negative effect on their efficiency. But IIRC the grav plate's effects are somewhat non-linear and below 50 g I seem to recall that they can hold the felt acceleration to 1g. (And even in the worst case, if their 30x reduction applied linearly, they do could so a 30g and below)

So as long as the forts stick to well under 100 g of acceleration there shouldn't be much, if any, impact on crew efficiency. (And probably not coincidentally we're told that they're restricted to well under 100g of acceleration)

And THAT does affect the design. If the grav plates can't compensate for 100% of the acceleration, then the entire design of the structure must be so that the direction of acceleration is "up". The spider-drive ships are like that, the typical "tower stack" with engines on the bottom that we see all the way from rockets to The Expanse.

Grav plates appear to be a much newer technology than compensators. In Travis', ships already had compensators, resulting in the ship always feeling zero gravity inside. But HMS Casey only got grav plates (and rail launchers) during the refit and was the first RMN ship to have them. The ships that the RHN was selling to the Casca Defence Force didn't have grav plates in 1535, so this wasn't because the Manticoran ships were particularly old.