Apollo Redundancy

tlb wrote:

cthia wrote:But, prior coordinates of the enemy must be input into the ACM. At what point is this knowledge input. If it is input inside the ship prior to launch, that would throw off the launch by quite a bit since a significant amount of time passes before launch; it is akin to the fact that the slightest jerk of the rifle of a sniper throws off his aim by quite a bit the longer the range. So, the ACM could receive the final launch instructions shortly into the launch X number of kms from the ship or even immediately after it passes close to the ship to re-establish contact. Which would be a window of vulnerability against a stealthy foe who has posted up a surprise near your ship / fleet.

I see no reason to distinguish between instructions received just before launch to those just after, since I do not believe the time required for the data transmission is significant. In the case of Beowulf, I would expect that it was input while the missiles were in the pods and that caused the pods to rotate to the proper direction (no ships involved).

Obviously with a ship able to fire off-bore (if I remembered that term correctly), it might be better to get the data after exiting the tube, but before the first stage ignites. If an invisible enemy ship is close enough to attack, then will not blow up the ship before launching the missiles?

tlb wrote:Some of that must be in all new pods, because I do not believe that those fired during the Solarian attack on Beowulf were system defense pods (I believe that is specifically mentioned in UH); after the production lines were blown up in the Oyster Bay attack, the concentration was on regular Apollo. Perhaps the only modification needed was an attached fuel tank for the pod's nuclear reactor.

cthia wrote:I agree the better option seems to be receiving the initial instructions after ejection. The fresher the instructions the better. But that exposes a window that the ACMs could be eliminated.

Also, consider that the missiles have to orient themselves after they leave the ship via a chemical based subsystem (rockets) or thrusters(?) via textev. All of that is time the enemy has moved. Of course, the ACM would have the ability to calculate current position and orientation, elapsed time, the current acceleration, range and vector of the enemy. But without those calculations the missiles would be hopelessly lost without sublight communication. But killing the ACMs would eliminate the force multiplier, and a launch at a stealthy but uncertain object would be handicapped without the collage of snapshots normally handled by the ACM.

I think we also might consider that without the ACM the orientation of the brood might not happen.

A collage of snapshots is a moot point anyway if the ACMs are lost.

ThinksMarkedly wrote:

cthia wrote:I agree the better option seems to be receiving the initial instructions after ejection. The fresher the instructions the better. But that exposes a window that the ACMs could be eliminated.

Do you really want to argue about eliminating ACMs in the second or two between launch and the impeller activation, when they are about 100 km from their launch platform? Why in the galaxy would anyone who can shoot at something as tiny as a missile from that range shoot at the missile? They should shoot at the mothership!

tlb wrote:Some of that must be in all new pods, because I do not believe that those fired during the Solarian attack on Beowulf were system defense pods (I believe that is specifically mentioned in UH); after the production lines were blown up in the Oyster Bay attack, the concentration was on regular Apollo. Perhaps the only modification needed was an attached fuel tank for the pod's nuclear reactor.

ThinksMarkedly wrote:Not necessarily. We know they weren't system defence missiles, so they weren't 4-stage missiles and I don't think it was the Mk23F version of the ACM either. But they may still be system defence pods, which have higher loiter endurance. Or it's the gantry system.

On the other hand, if those were Mk23F, it could explain why their accuracy was so good.

Though... how different are the Foxtrots from the Echos? What makes them good for system defence but not for offence?

The cursor moved to the very largest missile.
"This is the system-defense variant, the Mark 23-D, for the moment, although it's probably going to end up redesignated the Mark 25. It's basically an elongated Mark 23 to accommodate both a fourth impeller drive and longer lasing rods with more powerful grav focusing to push the directed yield still higher. Aside from the grav units and laser rods, this is all off-the-shelf hardware, so production shouldn't be a problem, although at the moment the ship-launched system has priority.
"With the Apollo missile itself—we've officially designated the ship-launched version the Mark 23-E, partly in an attempt to convince anyone who hears about it that it's only an attack bird upgrade—" the cursor moved to the third missile "—the situation's a bit more complicated. As I say, it's an entirely new design, and we're looking at some bottlenecks in getting it into volume production. The system-defense variant—the Mark 23-F—is another all-new design. Aside from the drives and the fusion bottle, we had to start with a blank piece of paper in each case, and we hit some snags getting the new transceiver squared away. We're on top of those, now, but we're still only beginning to ramp up production. The 23-F is lagging behind the 23-E, mostly because we've tweaked the transceiver's sensitivity even higher in light of the longer anticipated engagement ranges, which increased volume requirements more dramatically than we'd expected, but even the Echo model is coming off the lines more slowly than we'd like. When you factor in the need for the original Keyhole control platforms to be refitted to the Keyhole-Two standard, this isn't something we're going to be able to put into fleet-wide deployment overnight. On the other hand—"

tlb wrote:Mainly they are bigger, including the fourth stage. Here is the text from chapter 12 of Storm from the Shadows:

The cursor moved to the very largest missile.
"This is the system-defense variant, the Mark 23-D, for the moment, although it's probably going to end up redesignated the Mark 25. It's basically an elongated Mark 23 to accommodate both a fourth impeller drive and longer lasing rods with more powerful grav focusing to push the directed yield still higher. Aside from the grav units and laser rods, this is all off-the-shelf hardware, so production shouldn't be a problem, although at the moment the ship-launched system has priority.
"With the Apollo missile itself—we've officially designated the ship-launched version the Mark 23-E, partly in an attempt to convince anyone who hears about it that it's only an attack bird upgrade—" the cursor moved to the third missile "—the situation's a bit more complicated. As I say, it's an entirely new design, and we're looking at some bottlenecks in getting it into volume production. The system-defense variant—the Mark 23-F—is another all-new design. Aside from the drives and the fusion bottle, we had to start with a blank piece of paper in each case, and we hit some snags getting the new transceiver squared away. We're on top of those, now, but we're still only beginning to ramp up production. The 23-F is lagging behind the 23-E, mostly because we've tweaked the transceiver's sensitivity even higher in light of the longer anticipated engagement ranges, which increased volume requirements more dramatically than we'd expected, but even the Echo model is coming off the lines more slowly than we'd like. When you factor in the need for the original Keyhole control platforms to be refitted to the Keyhole-Two standard, this isn't something we're going to be able to put into fleet-wide deployment overnight. On the other hand—"

So it is possible that the system defense pods only have to worry about the missiles being longer and not fatter, but we do not know if that is true of the Mark-23F (Mark-25F ?). However you are proposing that the standard Apollo pods that likely come preloaded from the factory lines be unloaded and their missiles then loaded into the system defense variant, that seems to require excessive effort.

cthia wrote:I agree the better option seems to be receiving the initial instructions after ejection. The fresher the instructions the better. But that exposes a window that the ACMs could be eliminated.

Jonathan_S wrote:Well the Es are bigger with the 4th drive so they can accelerate up to 0.8c and then still have a 4th drive to maneuver laterally for terminal attacks.
The Fs add the longer ranged FTL transceivers - so the Mycroft relays wouldn’t need to be as close in order to still talk to them.

Jonathan_S wrote:

cthia wrote:I agree the better option seems to be receiving the initial instructions after ejection. The fresher the instructions the better. But that exposes a window that the ACMs could be eliminated.

At that point, after ejection and before targeting info is downloaded and the launch, they’d still be the pods.

An attack on them there wouldn’t just kill the ACM. It’d pretty much have to kill the whole pod. And that’s be beneficial for the defenders. But it’s be beneficial because you killed the whole pod; not because you somehow orphaned the other 8 missiles from their ACM

cthia wrote:I assume the missiles are fired directly from the pods? If so, how are the pods kept stationary while firing? Or are they ejected first? If they are not ejected then there will be wedge fratricide.

But the point at hand was that the same improvements could be applied to parasite pods, and, despite Hemphill's objections, they had been. Of course, the new pods—with ten tubes each, not six—were intended for ships of the wall, which had plenty of redundant fire control to manage them, not battlecruisers. But it sounded like Turner was finding the answer to that, and their missiles were actually heavier than the standard ship-to-ship birds. With the new lightweight mass-drivers BuShips had perfected, their performance could equal or even exceed that of normal, ship-launched missiles, and their warheads were more destructive to boot. The pods were clumsy, of course, and towing them did unfortunate things to a warship's inertial compensator field, which held down maximum accelerations by twenty-five percent or so. They were also vulnerable to proximity soft kills, since they carried neither sidewalls nor radiation shielding of their own, but if they got their shots off before they were killed, that hardly mattered.