More PDC related questions

[TallTroll (OP)]

For reference, here's the current state of my PDC design

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HomeBase class Planetary Defence Centre    30,950 tons     2093 Crew     4065 BP      TCS 619  TH 0  EM 0
Armour 12-87     Sensors 1/640     Damage Control Rating 0     PPV 137.16
Magazine 4474   

Twin R3/C3 Meson Cannon Turret (2x2)    Range 30,000km     TS: 12000 km/s     Power 6-6     RM 3    ROF 5        1 1 1 0 0 0 0 0 0 0
PDC Fire Control S06 36-12000 (2)    Max Range: 72,000 km   TS: 12000 km/s     86 72 58 44 31 17 3 0 0 0

PDC ASM (9) Launcher (12)    Missile Size 9    Rate of Fire 70
PDC AMM Launcher (6)    Missile Size 1    Rate of Fire 10
Missile Fire Control FC51 - R80 (PDC ASM 9) (3)     Range 51.5m km    Resolution 80
Missile Fire Control FC9-R1 (MR PD) (2)     Range 9.4m km    Resolution 1
AMM Mk1 (300)  Speed: 36,000 km/s   End: 0.5m    Range: 1m km   WH: 1    Size: 1    TH: 144 / 86 / 43
SS-1 50/9 ASM Mk1 (464)  Speed: 20,000 km/s   End: 41.7m    Range: 50m km   WH: 9    Size: 9    TH: 93 / 56 / 28

Active Search Sensor MR9-R1 (MR PD) (1)     GPS 160     Range 9.6m km    Resolution 1
Active Search Sensor MR485-R160 (PDC Deep Search) (1)     GPS 102400     Range 485.7m km    Resolution 160
Couple of things.

1) Armour is given as 12-87. Does that mean 87 columns of 12 blocks depth each? I think it does, but I've only assigned an armour rating of 8 in the design screen. I guess this is the benefit of more advanced armour

2) PDC missile racks. As this PDC will be sat on Earth, if I assign it to refill its' mags from "population", can I scratch some or all of the pathetically bad magazines, and use Earth based storage instead? Do I need one complete reloads worth of storage onboard for max efficiency? Or can I scratch them all?

I'd like to reduce the mags if possible, they are bulky, and very prone to explosion if anything gets through the armour. They also currently comprise around 50% of the DAC, so this thing is kind of a tinderbox, but I've no research points left to fix it

[Rastaman]

1) All PDCs have a generic armor bonus of four. So it is 12 deep and 87 wide.

2) You have 40 Salvos of your ASM missiles which is a lot. You have no reserves of AMMs, large numbers of AMMs are pretty important for point defense. Exchange some of the ASMs for AMMs. You can replenish from the population, but I don't know how long this takes and if this is economical in battle.

You want to throw some ordnance into space, but I think you can halve your magazine capacity and build multiple PDCs.

- Another point is that you have only a low number of AMM launchers. You need more of those too, maybe 12 too.

- Meson guns need power. You have no power plant! Each gun turret needs 6 power per 5 seconds, so your power plant(s) has (have) to provide at least 12. In the gun line, under "power" you have the entry 6-6. The first is the power needed per shot, the second per 5 seconds. Per turret. Because the ROF is 5 the two numbers are the same.

- The sensors and fire controls look ok.

[TallTroll (OP)]

1) Nice to know

2) Well, I've got 300 AMMs in stock, but yeah, thinking about it, I can fire them a lot faster than the ASMs. I'll rebalance the missiles

3) This design is intended to operate in conjunction with a PF Flotilla also operating from Earth, equipped with R3/C3 Mesons, and soon after another equipped with Gauss. Between that and the twin meson turrets on the PDC, I don't think PD is going to be a huge issue for a while. Developing some decent spaceborne PD platforms is a priority anyway. For now, I'll probably be using the PDC to paint the targets, and see about developing a specialised spaceborne sensor platform later

Also, this thing has a salvo weight of 108 damage at 50m km, with a cycle time of 70s. If that isn't enough to deal with anything that comes to say hello, a few more AMMs probably won't make the difference...

4) D'oh! I thought I'd put the power plants on there, thanks

[Hawkeye]

The thing is, yes, your ASMs deal a lot of damage - if they hit.

BUT there are only 9 of them in each salvo and salvos are seperated by 70 seconds.

This is kind of bad for two reasons.
A rather small "broadside" allows an enemy to concentrate its AMMs on those few missiles
A longish intervall between broadsides allows an enemy to concentrate on a single broadside at a time.

To overcome enemy PD, you have to either have missiles that are very hard to intercept (i.e. very very fast --> not an option for a loooong time) or you have to saturate the enemy PD, i.e. have a bloody lot of ´em in a bloody lot of salvos in as short a time as possible.

Your PDC can still work, if it can keep shooting longer than the enemy can shoot down your ASMs, i.e. if the enemy runs out of missiles before you do. This makes it necessary, however, to have your PDC survive that long, therefore, more AMM launchers are needed.

[Rastaman]

The weight of fire is not enough to meet the threats that are out there, but this can be remedied by building more of these defense centers. And indeed, they are only part of the defensive strategy.

[TallTroll (OP)]

There are 12 in the broadside, I put the (9) in the launcher name myself, as a note of the launcher size. With 3 FCs, I can also launch them as 3 salvoes of 4, to complicate enemy PD. I gather they like using the 3-1 setting, so 4 unit sub salvoes will maximise the chances of some getting through.

I'm kind of stuck with low tech stuff, since this is the start of the game, so there's not so much I can do about it. Yes, smaller missiles fire faster, in larger salvoes, which is all good, but I'm deliberately placing heavier ASMs on the PDC, because it gets a native increase in fire rate on the launchers. I have a dinky little size 6 design with 4 WH for spacegoing applications. With my current tech, a ship based Sz 6 launcher actually has a 90 sec launch cycle...

>> Your PDC can still work, if it can keep shooting longer than the enemy can shoot down your ASMs, i.e. if the enemy runs out of missiles before you do. This makes it necessary, however, to have your PDC survive that long, therefore, more AMM launchers are needed.

I can see any ship that would represent a threat from way out, and with 50m km range, I've got time to shoot a *lot* of missiles. As it happens, a target advancing at 5000km/s would reach the PDC just as the last missiles in the magazine launched, now I have a 30 salvo load. The AMMs won't be alone, either. There are 2 twin meson turrets (with power now, natch), and there will be at least 2 PF flotillas on station for extra protection, once I can get them up, plus whatever fleet elements are present. I think it likely I'll leave a fair size squadron over Earth for some time.

This isn't meant to be a one-base-to-defend-the-Earth deal, it's just what I can do with what I've got. It's adequate for driving off smallish FF fleets, or low tech early warships perhaps, but it's mostly a fixed supplement to what I can put in space. A last line of defense, not the first.

I'd really like to place a PDC on Luna, to take advantage of the lack of atmosphere, but I don't think I can, as it's not colonisable. Shame

>> The weight of fire is not enough to meet the threats that are out there

If some super-teched alien comes swanning into Sol by 2027, I'm pretty much screwed whatever I do, so I'm just not going to worry about it. This PDC will keep alien survey ships and light warships off me, which is all that's required of it

[Gidoran]

Something being listed as not suitable for colonization just means that your populace can't live there. You can still put a colony there, and PDCs. In fact, this is the reason that orbital habitats exist: You just dump a couple in orbit directly over the planet, and you can put a populace down without them slowly dying due to holy crap this is violating humanities warranty.

[TallTroll (OP)]

Oh, OK, I take it I'd have to "build as prefab", ship the sections to Luna, get an orbital habitat over Luna, and some construction factories, and then (finally) "assemble from prefab". Whelp, that'll only take about as long as researching / designing / building some guns to go on it anyway...

As for the original question... if I set my Earth PDC to "fast reload from population", could I then dump some of the dangerous tinderbox magazines, and draw ammo directly from Earths stockpiles? Or will I need to keep at least some ready ammo on hand in the ord. management tab?

[Hawkeye]

Yeah, I noticed the 12 later and forgot to edit my post accordingly

Low tech stuff is ok, you work with what you´ve got (this is some of the charme of aurora)

The enemy using 1 : 3,   I´m not sure you understand that setting entirely. This setting means, that the enemy will launch 3 AMMs at any ASM you launch at them. If your salvo is 4 missiles strong, the enemy will launch 12 AMMs at that salvo. Assuming, on interception, two of your ASMs are shot down, the remaining 2-missile-salvo will now be the target of 6 new AMMs.

The limiting factor here is not the size of the salvo, but the number of AMM launchers and/or the number of AMM firecons.
Many small salvos will tax the enemy PD, because there are not enough firecons, to target all salvos simultaneously
Few very large salvos will do the same, because the enemy can not get enough AMMs into space fast enough

On a side note, a range of 50 mkm is nothing extrodinary. Sure, if the enemy comes with beam ships, you can rip him to shreds, but if he comes with his own missile ships, he might outrange you.
Just something to keep in mind.

You can put a few engineering brigades on luna and let them assemble the PDC (there used to be a bug, that you would have to have at least a single factory for this to work. I don´t know if Steve fixed that. If not, just SM in a factory and after the PDC(s) have been assembled, delete it again (no, it doesn´t need any workers for the brigades to start working)

And yes, you can instant-reload from population (You might need to have at least enough mag-space for one reload, but I am not sure on that) but I would consider that cheating when done during combat.
Of course, it is your game you are playing, so you can do whatever you want

[Garfunkel]

That bug is fixed, no need for a single CF any more.

[TallTroll (OP)]

>> The enemy using 1 : 3,   I´m not sure you understand that setting entirely

More than possible. When I actually get to see an enemy ship, I'll find out how well this stuff works...

I'll be backing up the PDC with PFs, and a couple of missile destroyers. The DDs I can probably leave without a serious sensor, use the PDCs one for target acquisition for now, and build a dedicated sensor platform or two for expeditionary work. They will carry the size 6 missile (faster, but WH4)

>> On a side note, a range of 50 mkm is nothing extrodinary.

No, but again it falls into the category of "what I've got" at the moment. I'm not sure I can feasibly build a sensor with much better range than that anyway, and it's taxing the limits of my missile tech too. I'll have more mobile forces available soon. Mostly, I want to keep Earth from getting toasted by some stupid basic scout with a 10cm Infrared laser

>> You can put a few engineering brigades on luna and let them assemble the PDC

Hmm, I've not really looked hard at enginners yet. I gather I'll need a 5 Btn lift capacity to take them anywhere, and I knew they could work on ruins. Didn't realise they could build stuff like that too. Ah, is that why Earth has 400 / 2 / 0 in the construction screen? The existing Engineers?

If you've ever read Earthlight by Arthur C Clarke, I wanna build Project Thor  

>> And yes, you can instant-reload from population (You might need to have at least enough mag-space for one reload, but I am not sure on that)

I'll want it to have some internal magazine in any case. Earth stocks might run dry for all sorts of reasons, but I would really like to cut some of them out of the design, they are an accident waiting to happen. I don't have a problem with co-locating Earth based storage and PDC magazines. If you have a ship with a fleet flagged as a collier, as far as I can see, they just chuck the missiles across space, presumably between open airlocks. It's no less realistic than that

[Theokrat]

Just a minor point:

As pointed out, PDCs can instant-reload from a friendly population if the PDC has enough “magazine space” for one reload. But this is always the case, as missile launchers always contribute a single reload worth of magazine space to the design (e.g. a size 9 ML contributes 9 magazine space). So theoretically you could get away without any dedicated magazine component on the PDC if you can make reasonably sure that the population can provide the missiles. However it can be theoretically worthwhile to provide some space in order to keep the design operational, even if an enemy manages to land troops on the planet (and takes over the friendly population with its missile stocks). In this case a dedicated magazine would allow the PDC some residual capacity to fend of incoming ships and engage the hostile ground units. Yes this scenario is unlikely to occur against the AI.

Long story short: You can safely drop all but a few magazines (as already pointed out).

[Garfunkel]

Having 1 or 2 reloads in magazines in the PDC will also prevent you from accidentally emptying the stockpile of missiles on the colony, if your PDC uses same missiles than your ships.

[sloanjh]

As pointed out, PDCs can instant-reload from a friendly population if the PDC has enough “magazine space” for one reload.

This is a case of a part of the game that needs to be role-played around.  It's not that it takes no reload time, it's just that the game doesn't track reload time.  So one should pick whatever number one wants for reload time (I typically use something on the order of an hour) and not do reloads on shorter time scales.  Remember, Aurora doesn't keep you from "cheating at solitaire".

In other words, the answer to the OP's poster is "yes you can scratch them, but it's a bit exploit-y"

John

[xeryon]

The thing with the 50m range on the FC that no one has brought up yet that amused me is ECM.  Yes this is a last ditch defense center and intended for light craft defense.  I routinely find AI ships with greater than 50m range AND they have ECM which often brings my range down to 25-30m or so.  I can easily see a couple smallish missile craft unloading their entire magazines vastly beyond the range of your FC and vacating the area long before chase craft can close in.