[FT] Weapons Design System Concept - some numbers

Ok, some further thoughtson this:

Oerjan's 'total cost' (TC from now on) formula is:

TC =
Cost of system (MASS x COST/MASS)
+ cost of fraction of engines used to push system (0.2 x MASS x 2 for
Thrust 4 human engines)
+ cost of fraction of FTL drive used for system (0.1 x MASS x 2)
+ cost of fraction of hull that holds system + drive fractions ([1 + 0.2
+ 0.1] x MASS x 1)

where MASS is mass of system, COST/MASS is cost per mass of system.

simplified:

TC = MASS x {Cm + (Ct + 1) x THRUST/20 + 1.3}
where Cm is COST/MASS, Ct is cost per mass of main drive, and THRUST is
an average thrust value.

For average (FB1) human ships, say Ct=2, THRUST =4, which gives

TC(human) = MASS x (Cm + 1.9)

re-arranged, MASS = TC/(Cm + 1.9)
(useful for working out MASS & COST of modified systems)

For Kra'Vak, Ct=3, THRUST =4 (say), which gives

TC(KV) = MASS x (Cm + 2.1), or MASS = TC/(Cm + 2.1)

Ok, so, here are some numbers I've worked out:

Note: a lot of these involve fractional TC values - all fractions should
be kept until the final mass and cost values are determined, in which case
they should be rounded up to the next highest integer value (if in
doubt - over-price).

1) Change in Range Bands:

As most weapons use range bands of either 6mu or 12mu, I will give the TC
modifiers of changing these to some other value:

6mu Range Bands (Pulse Torpedoes, SMPs, K-Guns, Pods)

New Range Band TC Multiplier 2 mu x 0.15 3 mu x 0.3 4 mu x 0.5
8 mu            x 1 2/3
9 mu x 2 10 mu x 2.5
12 mu           x 3 1/3

12 mu range bands (Beams)

New Range Band TC Multiplier 3 mu x 0.1 4 mu x 1.5 6 mu x 0.3 8 mu x 0.5 9 mu
x 0.6 15 mu x 1.5
16 mu           x 1 2/3
18 mu x 2 20 mu x 2.5
21 mu           x 2 2/3
24 mu           x 3 1/3

In either case, should the new maximum range exceed the maximum range of the
base weapon by 12 mu or more, then the TC of the modified system should be at
least twice that of the base system (with further doublings
for each additional +12 mu).

2) Reduce number of fire arcs

At the moment, this only applied to Class-1 weapons (B-1s and K-1s),
Class-2 beam batteries, stinger nodes, and placed marker weapons (SMs,
PBLs) - B-1s, B-2s, K-1s, and Stingers are all too small to be further
reduced. So we can probably do without this one ATM.

3) Add PDS capability.

Oerjan values this as +4 to TC for all-arc PDS capability, in which case
the cost of 'PDS as B-1' is +2 1/3 to TC, and the cost of 'PDS as K-1'
is +1 2/3 to TC. In both cases this is all-arc coverage, limited arc
coverage will have a reduced cost (TBD).

Digression - IIRC somewhere it is stated that B-1s and K-1s used as PDS
require an active fire control - but I can't find this in either Fleet
Book! - if so, then being able to function as PDS without a firecon
should cost slightly more than being able to function as PDS with a firecon.

4) Reduce MASS and Increase COST, or Increase MASS and Redunce COST:

Just calculate the systems TC, then try different values of Cm in the
re-arranged formula until you get one that gives a close to integer
value for the MASS in the range you want:

For example - lets build an archaic 1-arc pulse torpedo (more MASS, less
COST)

a 1-arc pulse torpedo is MASS 4, COST 12, COST/MASS 3
so:
TC = 4 x (3 + 1.9) = 4 x 4.9 = 19.6
say we increase MASS to 5; TC = 19.6 = 5 x (Cm + 1.9),
so Cm = 19.6/5 - 1.9 = 2.02
So our archaic pulse torp is MASS 5, COST 10, COST/MASS 2, TC 19.5
slighly lower TC (by 0.1), probably not a major problem :-)

5) Burnout - every time the system is used, it must make a threshold
check - if it fails, it is damaged.

I'm not totally sure about these numbers yet:

Threshold Roll needed
                                6       5+      4+      as ship
Threshold before system used x.7 x.5 x.4 x.5 Threshold after system used x.85
x.75 x.7 x.75

6) One-Shot and limited use

Number of uses TC Multiplier 1 x0.5 2 x0.75
3+              x1

7) Hardened/Fragile (and yes, I worry about these)

Add the level of hardening to the threshold number (6's always fail)

Level of Hardening TC multiplier restricted to
1                       x 1.5           1-arc weapons, SML magazines,
all drives 2 x 1.75 SML magazines, Advanced drives, FTL 3 x 2 FTL drives

super hardening (and I'm _really_ not sure about this one!)
as hardening, but 6's do not automatically fail!

Level of Super hardening TC mult. Restricted to 1 x 1.5 Magazines, Advanced
Drives, FTL 2 x 2 Advanced Drives, FTL 3 x 2.5 FLT drives

Fragile - TC multiplier of x2/3: subtract 1 from threshold numbers
(first becomes roll of 5+, etc.)
Very Fragile - TC multiplier of x1/3: subtract 2 from threshold numbers

Well, those are the numbers I've worked out so far - and some of them
are a bit tentative as yet.

> Charles Taylor wrote:

> Ok, some further thoughtson this:

Um, no. The engines don't use 30% (ie. 20% + 10%) of the Mass of the
*system*; they use 30% of the Mass of the *system + engines*. That's a
pretty important difference - your "0.2 x MASS" and "0.1 x MASS" in the
engine terms above should in fact be 0.2*1/(1-0.2-0.1)*MASS and
0.1*1/(1-0.2-0.1)*MASS respectively (ie., 0.29*MASS and 0.14*MASS), and
the
hull cost is MASS*1/(1-0.2-0.1) = MASS*1.43

The full TC formula for an FTL-capable ship is

(System MASS)*(1 [basic hull] + Cm + THRUST/20/(1-0.1-THRUST/20)*(Ct+1)
+
0.1/(1-0.1-THRUST/20)*(2+1))

where Cm is COST/MASS, Ct is cost per mass of main drive, and THRUST is
the thrust value of the main drive.

For a thrust-4 Human-drive FTL-capable ship we get THRUST = 4, Ct = 2,
so the formula becomes

TC = (System MASS)*(1 + Cm + 4/20/(1-0.1-4/20)*3+0.1/(1-0.1-4/20)*3) =

= (System MASS)*(1 + Cm + 0.2/0.7*3 + 0.1/0.7*3) =

= (System MASS)*(Cm + 2.3)

Similarly for a thrust-4 Kra'Vak ship (Ct = 3) it becomes

TC = (System MASS)*(Cm + 2.6)

Now re-calculate all your values based on these updated formulae <g>

> Note: a lot of these involve fractional TC values - all fractions

Yep.

> 2) Reduce number of fire arcs

In Cinematic, a 6-arc weapon is worth somewhere between one-third and
one-half more than a 3-arc one as long as the range is greater than
12mu.
If the range is 12mu or less, the 6-arc weapon can be worth as much as
double that of the 3-arc weapon.

The decrease from 3 to 1 arc depends heavily on the weapon's range and on
the ship's thrust, but again an increase of 50-100% is appropriate. The
faster the ship is and the longer range the weapon has, the less worth are
extra fire arcs.

However, if you play Vector none of the above applies!

> 3) Add PDS capability.

I'd estimate that 'PDS as B1' (exactly 1/2 of full PDS) is +2 TC, while
'PDS as K-1' (1/3 of full PDS) is +1.33. (It is an addition to the TC,
not
to the cost of the system alone - thus no extra 1/3!)

> Digression - IIRC somewhere it is stated that B-1s and K-1s used as PDS

That's in MT. I suggest that this rule be ignored though :-/

[hardening snipped - the figures look similar to what I arrived at long
ago, but I no longer have those files]

Later,

In message <5.1.0.14.1.20010611195306.009f9a30@m1.853.telia.com>
> Oerjan Ohlson <oerjan.ohlson@telia.com> wrote:

> Charles Taylor wrote:

> pretty important difference - your "0.2 x MASS" and "0.1 x MASS" in

D'oh, I though it was going to easy - forgot that bigger engines need to
be even bigger to push themselves :-(
> The full TC formula for an FTL-capable ship is
Well, I tried the new numbers on my 'Archaic Pulse Torp' example - and
the final answer (after rounding) looks the same, however, it has now
been rounded _up_ rather than _down_ slightly.

[snip]
> >3) Add PDS capability.

Hmm.. I calculated 'PDS as B1' as being slighly more than half as
effective as a PDS - I'll check.

Of course, this is for all-arc coverage - any ideas on the TC mod for
3-arc PDS (or PDS as B1) capability? 1-arc? (probably not a lot).
> >Digression - IIRC somewhere it is stated that B-1s and K-1s used as

Makes things simpler.
> [hardening snipped - the figures look similar to what I arrived at