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Posted by: TheDeadlyShoe
« on: February 14, 2012, 06:28:38 PM »

Quote
Unless the PDC is on an airless world it's useless,
A lot of generated systems have planets with moons rotating fairly closely. Also, it's expensive to stock distant worlds with lots of missiles, and not all targets worth defending have a lot of air pressure :)

Posted by: Grunden
« on: February 14, 2012, 04:40:11 PM »

Quote from: Sloshmonger link=topic=4630. msg46704#msg46704 date=1329252847
It can work, but most times I've tried that the escorting beam defence boat ends up the first target, and since the only support it can get is AMM, it tends to die.   I've worked Area defence laser boat + GC Escort boat pairings on it and it works better (or you could add both to the same boat).

I wonder if it might be more effective if you wait until the missiles are incoming before detaching (i. e.  targets have already been committed).  Stop/reverse the main body for a couple of increments until you achieve the desired spread.

Quote from: Charlie Beeler link=topic=4630. msg46705#msg46705 date=1329253506
If you have the resources for build fleets with that complexity it can work.   Personally I try to stick with the KISS principal as much as possible.   

I don't see how that greatly complicates fleet design, assuming you have beam-armed PD escorts in the first place.  I suppose you would need bulkier fire controls than one that is strictly limited to point blank.  I guess it would depend if you wanted to dedicate a design to that specific role or one that could operate in either 'ring'. 

I simply like to have options (for RP reasons if nothing else) for different fleet doctrines; including ones that might be sub-optimal.  Optimal is easy (for me, that's carrier based missile strikes backed by a size 50 sensor).
Posted by: Charlie Beeler
« on: February 14, 2012, 03:05:06 PM »

What about detached beam escorts 200k or so out from the main body in area defense mode? Isn't this the intent behind the escort formation controls?

If you have the resources for build fleets with that complexity it can work.  Personally I try to stick with the KISS principal as much as possible. 
Posted by: Sloshmonger
« on: February 14, 2012, 02:54:07 PM »

What about detached beam escorts 200k or so out from the main body in area defense mode? Isn't this the intent behind the escort formation controls?

It can work, but most times I've tried that the escorting beam defence boat ends up the first target, and since the only support it can get is AMM, it tends to die.  I've worked Area defence laser boat + GC Escort boat pairings on it and it works better (or you could add both to the same boat).
Posted by: Grunden
« on: February 14, 2012, 01:59:40 PM »

What about detached beam escorts 200k or so out from the main body in area defense mode? Isn't this the intent behind the escort formation controls?
Posted by: Charlie Beeler
« on: February 14, 2012, 12:59:09 PM »

I'd like to note that PDC beam fire controls make area defence practical in that limited context. For example:

Code: [Select]
Z200 class Planetary Defence Centre    7,500 tons     1200 Crew     1431 BP      TCS 150  TH 0  EM 0
Armour 7-34     Sensors 1/32     Damage Control Rating 0     PPV 100

Anti-Proton Cannon (4)    Range 200,000km     TS: 4000 km/s     Power 10-3    ROF 20        4 4 4 4 4 4 4 4 4 4
EMC 150mm "Gustav" (12x4)    Range 120,000km     TS: 4000 km/s     Power 9-3     RM 4    ROF 15        3 3 2 1 1 1 0 0 0 0
Cyberdyne RTT Defender (3)    Max Range: 384,000 km   TS: 5000 km/s     95 90 84 79 74 69 64 58 53 48
GCF Series 29 (6)     Total Power Output 54    Armour 0    Exp 5%

Naval X-Band Scanner (1)     GPS 32     Range 3.5m km    Resolution 1
Commercial Radio (1)     Sensitivity 8     Detect Sig Strength 1000:  8m km

ECCM-1 (1)         
This design is classed as a Planetary Defence Centre and can be pre-fabricated in 3 sections

That's with 20,000 km range bands and 32kkm fire control tech.  Neither weapon is particularly well suited to area defence, but the PDC-grade fire control is easily capable of adequate to-hits at long enough range to get off a single area defence salvo and that's all I really need out of it.

@Theokrat - I would say that large missiles at least mean you aren't suffering any opportunity cost from using miniaturized launchers.  You aren't going to win the reload-rate game anyway so you might as well front load.

Unless the PDC is on an airless world it's useless, the only beam weapon that suffers no damage degridation from atmospheric density is the Meson Cannon.  And unless the incoming ordinance is really slow the chances of actually hitting one is extremely low.  The hull spaces are better spent on AMM suites.
Posted by: TheDeadlyShoe
« on: February 14, 2012, 12:26:25 PM »

I'd like to note that PDC beam fire controls make area defence practical in that limited context. For example:

Code: [Select]
Z200 class Planetary Defence Centre    7,500 tons     1200 Crew     1431 BP      TCS 150  TH 0  EM 0
Armour 7-34     Sensors 1/32     Damage Control Rating 0     PPV 100

Anti-Proton Cannon (4)    Range 200,000km     TS: 4000 km/s     Power 10-3    ROF 20        4 4 4 4 4 4 4 4 4 4
EMC 150mm "Gustav" (12x4)    Range 120,000km     TS: 4000 km/s     Power 9-3     RM 4    ROF 15        3 3 2 1 1 1 0 0 0 0
Cyberdyne RTT Defender (3)    Max Range: 384,000 km   TS: 5000 km/s     95 90 84 79 74 69 64 58 53 48
GCF Series 29 (6)     Total Power Output 54    Armour 0    Exp 5%

Naval X-Band Scanner (1)     GPS 32     Range 3.5m km    Resolution 1
Commercial Radio (1)     Sensitivity 8     Detect Sig Strength 1000:  8m km

ECCM-1 (1)         
This design is classed as a Planetary Defence Centre and can be pre-fabricated in 3 sections

That's with 20,000 km range bands and 32kkm fire control tech.  Neither weapon is particularly well suited to area defence, but the PDC-grade fire control is easily capable of adequate to-hits at long enough range to get off a single area defence salvo and that's all I really need out of it.

@Theokrat - I would say that large missiles at least mean you aren't suffering any opportunity cost from using miniaturized launchers.  You aren't going to win the reload-rate game anyway so you might as well front load.
Posted by: Theokrat
« on: February 14, 2012, 10:36:58 AM »

Still... I have a personal preference for size-6 strength-9 missiles despite the bulkier ammo storage and slower reload. I find that weight of alpha-strike is just as important as weight of sustained fire in most engagements, since the first side to land a really devastating hit will usually win the engagement.

Last point by me on missiles in this thread (promise!), but using different missile sizes (or launcher sizes) does not represent a trade-off involving the weight of the alpha-strike.

Suppose you have designed a ship with 12 Size-6 launchers. These will weigh 12*300t=3,600t in total (for normal-size/normal reload). If you would be using size-4 missiles (and launchers), then for the same weight (and buildpoints?) you could have 3,600t/200t=18 launchers. Put differently, you can either launch 12*6=72 MSP in the first strike, or 18*4=72 MSP. Since the suggestion is to devote the same proportion of the missile to the warhead, the alpha strike has the same exact weight – regardless of the missile size.

Missile size is thus not a trade-off between sustained fire and first strike weight (that is exclusively for the size/reload rate techs-regardless of the missile size). The trade-off is between PD-penetration (more missiles in one salvo that need to be engaged, and more frequent salvos -> less time to deal with each) on the one hand, and armour-penetration (warhead size of the individual missiles).

You can advocate large individual missiles by stating that you want to achieve “deep damage”, and that this objective outweighs the drawback (to some degree) of dealing less total damage, as more payload is destroyed by enemy PD before reaching the target. However, the goal of having large individual salvos has little to do with the size of the individual missiles.
Posted by: Arwyn
« on: February 13, 2012, 04:27:32 PM »

The are several problems with using laser turrets in area mode in place of gauss turrets in final mode. 

First is that you need at least a tech parity with op-for to have laser and fire control tech that gives you enough range to engage.  To have a regular chance to even fire in area mode your weapons suite needs to have a range to is close to matching the incoming missiles 10 second movement.  This is because you should not rely on the incoming salvos stoppin inside their 5 second movement range (or even closer).  Remember that area mode PD beam fire occurs during the normal weapons fire phase and not during movement like final fire.  Beams that have this kind of range are very slow firing unless you have invested nearly all your research into capacitors so that your large beams have 5 second cycles.  Another issue is that the chances to hit at these ranges will suck before the modifiers kick in for having a tracking speed that is inferior to the missile speed.

The only way these issues are negated is by having a significant tech advantage. 

In the current game environment beam area point defense is not really viable because of how fast missiles move.  A main defense of AMM's and fast firing beams in turrets for final defense is the best you can hope for.

I completely agree. Thats why I either use just Gauss and AMM's for a 2 layer, or Gauss, beam, AMM for three. The advantage to having a 3 layer as opposed to 2, is the slight chance of picking off a few additional missiles before the Gauss engage. It also gives you offensive beam capability if your not dragging around dedicated beam platforms, or augments what you already have.

Once you missile closure speeds start getting north of 40,000 km/s it starts becoming increasingly hard unless you pump points into laser wavelength. My experience was that 12cm and 15cm lasers worked the best, 20cm and above take prohibitively high amounts of RP to get down to 5 sec recycle times. 10 and 15 second cycle times DO work if the enemy reload rate is fairly long, but those cycle times hurt if the missiles reloads are the same.

Thats one of the reasons I stick with size 4 missiles for the most part, the reload speeds are fairly cheap in RP to bring you to a fast reload time compared to a size 6.
Posted by: Thiosk
« on: February 13, 2012, 02:41:58 PM »

Though curiously most all the NPRs seem to use thin armor. 

They sure seem to.  its fairly early game for me to start getting 12-15 layers on, and the ai seems to not do as such. 

For this reason, my warhead 32 size six missiles are brutally effective when they penetrate (which, since both races I have fought this game were unable to defend against missiles effectively, worked very well.  All they had was CIWS and a few AMM corvettes).
Posted by: TheDeadlyShoe
« on: February 13, 2012, 01:07:29 PM »

the reload rate is kind of the nail in the coffin for going up in missile size.   Basically you might as well go box launchers/ 0.25x launchers at that point and ALPHA LIKE MAD. 

the difference between 20 seconds and 30 seconds stacks multiplicatively with the difference in quantity... this is also why AMM sandblasting is so ridiculously effective. Honestly, for missile size to be more effective, the reload rate difference would have to largely go away...  though that would have interesting implications for AMMs!

Also, the difference between size 4 and 9 warheads kind of disappears if you're hitting armored targets, like 8-9-10 layers.  And obviously makes no difference against shields. Though curiously most all the NPRs seem to use thin armor. 

Posted by: blue emu
« on: February 13, 2012, 12:20:51 PM »

Another point worth noting is that smaller missiles reload more quickly, so a ship-load of half-size missiles will actually inflict more damage per unit time (assuming that the same displacement is allocated to launchers).

Still... I have a personal preference for size-6 strength-9 missiles despite the bulkier ammo storage and slower reload. I find that weight of alpha-strike is just as important as weight of sustained fire in most engagements, since the first side to land a really devastating hit will usually win the engagement.
Posted by: Theokrat
« on: February 13, 2012, 09:47:41 AM »

Nitpick: In my experience, warhead 6 has a damage profile of 4-tiles on the first layer, 2 on the second: so warhead 6 inflicts twice the layer-2 damage as a warhead 4. This makes the square + depth numbers 6, 12, etc almost as good as the true squares 4, 9, etc.
Yeah I noted the slight error after posting, so I already edited it. Extremely nitpicking myself, a warhead 4 inflicts 33% less layer-2 damage per warhead that hits, compared to warhead 6. However, warhead 9 would inflict even 33% more layer-2(onwards) damage, and be able to do layer 3 damage.

In other words: If is a viable trade-off to increase the missile size by 2 points in order to get 1 more point of layer-2 damage (exchange rate 2:1), would it not be sensible to increase the size by 3 points in order to get 2 more points of layer-2(+) damage (exchange rate 3:2=1.5:1? Technically speaking, the marginal return of "deep damage" is much higher when moving to square numbers. Of course I accept that the marginal return of more missiles is also highly non-linear (i.e. doubling the amount of missiles more than doubles the amount of missiles which will get through).
Posted by: sublight
« on: February 13, 2012, 09:12:15 AM »

Why did I enter into this lengthy debate? Simple, because it allows you to easily spot that something about a missile might be somewhat off when its large and does not have an optimal damage profile (spell: the warhead is not a square number). And that is the case for your missile: Size 6, Warhead 6. What damage profile would this cause? 5 tiles of the first layer of armour, 1 tile of the second. Now suppose you decreased all the allocations of the missiles by 1/3. You would get a size 4 missile with the same speed, same range, same hitchance, but warhead 4. This would have a damage profile of 3 tiles on the first layer, 1 to the second – so the penetration depth would be the same. In essence you would get a design that is harder to intercept, can be launched more rapidly, and would cause the same (actually a bit more) damage on the enemy.

Nitpick: In my experience, warhead 6 has a damage profile of 4-tiles on the first layer, 2 on the second: so warhead 6 inflicts twice the layer-2 damage as a warhead 4. This makes the square + depth numbers 6, 12, etc almost as good as the true squares 4, 9, etc.
Posted by: Theokrat
« on: February 13, 2012, 08:48:03 AM »


Cometchaser ASM Mk II: (1-6, 2-10, 1-2500, 2-160)
Code: [Select]
Missile Size: 6 MSP  (0.3 HS)     Warhead: 6    Armour: 0     Manoeuvre Rating: 37
Speed: 33300 km/s    Endurance: 30 minutes   Range: 59.9m km
Cost Per Missile: 5.5083
Chance to Hit: 1k km/s 1232.1%   3k km/s 407%   5k km/s 246.4%   10k km/s 123.2%


A few points on the missiles: It is important to realize that all characteristics of an unguided missile (i.e. without sensor) scale with the size of the missile.

So if you double all stats you will have a missiles that is just as fast (except minor rounding), has exactly the same range, and the same Manoeuvre Rating (and thus the same chance to hit). It does however have twice the warhead and is twice as expensive (to build and to research). The launchers for a missile also scale with the size, so the launcher gets twice as large, or put differently, you could only have half of the launchers on a given ship ceteris paribus. Equally the space a missiles takes in the magazines is proportional to its size, so you can pack half as many of the twice as large missiles.

The important implication is that the damage that you can expect to do to an enemy without PD is independent of the size of the missiles that you choose. Both in terms of one salvo, and in terms of your entire magazine capacity: You can either launch n missiles which do x damage each, or 2*n missiles which do x/2 damage each, while both are equally likely to hit.

Of course most enemies do have PD defences, and interestingly enough PD defences allow to engage a certain number of missiles, independently of their individual size (actually smaller missiles can be a bit harder to engage, since they are detected later by radar). So the expected raw damage you can project on an enemy massively favours a large number of small missiles, rather than a smaller number of large missiles: Suppose they can intercept m missiles every round, then you could deal raw damage of (n-m)*x, or (2n-m)*x/2=(n-m)*x+m/2. Note the later term is always larger than the former. Furthermore the reload time of a launcher scales with the size of a missile, so using the smaller missiles also allows you to launch them much more rapidly, increasing the damage dealt per second, and potentially even increasing enemy PD penetration further, as he might still deal with the first salvo, when the second shows up.

Yet there is also a reason to use larger missiles, which is due to the damage profile of missiles. When a missile hits it will leave a triangular shaped damage profile on the enemy armour, with the total penetration depth depending on the size of the warhead. For instance a 4-Warhead missile will destroy three tiles of the outermost armour layer, and one tile of the second layer when it hits. A 9-Warhead missile will destroy 5 tiles of the outermost layer, 3 tiles one layer below, and one tile on the third layer. If the respective layer does not exist its applied as internal damage. If the original missile had a warhead of 2, then the double-sized missile would have a warhead of 4. The later would be able to penetrate deeper and thus be more likely to do internal damage towards an enemy earlier. E.g. if the enemy had only 1 layer of armour then the large missile would deal internal damage from the first hit on, while at least two the smaller missiles would need to hit the same spot to do internal damage. There are twice as many, but its unlikely they hit the same location. For unguided missiles this is the only reason why you would want to use large missiles rather than smaller ones (except rounding effects).

Why did I enter into this lengthy debate? Simple, because it allows you to easily spot that something about a missile might be somewhat off when its large and does not have an optimal damage profile (spell: the warhead is not a square number). And that is the case for your missile: Size 6, Warhead 6. What damage profile would this cause? 4 tiles of the first layer of armour, 2 tile of the second. Now suppose you decreased all the allocations of the missiles by 1/3. You would get a size 4 missile with the same speed, same range, same hitchance, but warhead 4. This would have a damage profile of 3 tiles on the first layer, 1 to the second – so the penetration depth would be the same. In essence you would get a design that is harder to intercept, can be launched more rapidly, and would cause the same damage on the enemy.

Another thing is that your hitchances are very high. Your missile has a 123% chance to hit an enemy traveling at 10k km/s. 23 percentage points of that are wasted (assuming average crew grade), as of course hitchances are capped at 100%. Unless you are very certain that you will be facing very very fast enemies, this is a suboptimal design. It could be improved by diverting space from “agility” towards other categories, increasing the damage, speed or range of the design, without losing anything that is not superfluous to begin with.


Lastly, its often a good idea to arm with a mixed of obsolete and up-to-date missiles, not just because it saves resources, but also because they have different velocities. If done properly they can be launched at different times such that they arrive at the enemy at roughly the same time, saturating his PD defences.