Re: Re:Armor

Bell, Brian K wrote:

[Ka-snip - if you've forgotten Brian's proposal, check the archives]

>>All in all, this armour is *much* more powerful than level-2 screens,
>>so needs to cost correspondingly more, or use more Mass. (Except
>>against K-guns, of course - reducing their "damage rolls" by 1 makes
>> them *more* likely to inflict double damage, not less.) 
>> 
>>If you retain the Mass values given above, it's worth over 20xMass -
>>the protection given is massive, and the armour Mass over which you
>>can distribute this cost is very small. I haven't had time to look at
what
>>it'd be worth if it used more Mass, sorry.
> 
>Sorry, I was unclear in my statements.
>When I stated that a "6 always hits" I was trying to state the
following:
>  A roll of a '6' is always treated as a roll of a '6'.  
>So a roll of a '6' with a beam weapon does 2 points of damage and
>allows for a penetration roll; a roll of a '6' with a needle beam
still >destroys the targeted system; etc.  I was unclear.

OK, that's quite a difference - makes the armour equivalent to
level-*1* screens vs beam dice instead of level-2, and doesn't stop
precision needle damage.

>I also forgot to address K-Guns. For K-Guns damage, treat
>K-Guns as 1 class less than thier rating (minimum of 1).
>Do not subtract 1 from the damage roll. 

The cost of armour just went up further still... K2s are completely
gutted; for K3s it's only equivalent to level-2 screens vs beams, and
then the effect falls slowly until it's no worse than level-1 screens
for the K6.

>Your estimate of 20xMass cost value seems high. Remember
>that we are addressing limited arcs of protection.

The 20xMass was calculated on a straight "-1 to the die" for beams
(ie., equivalent to level-2 screens rather than level-1 screens),
without taking any of the other weapon types into account (that pushed
the cost closer to 30xMass). With the above adjustments, it's not quite
that drastic - still bad, but not quite *that* bad.

I did remember the limited arcs. They are a major cause to the problem,
not a solution to it.

>Assume for argument sake that an average pilot can 
>maneuver so that he can place 3 arcs between his ship
>and the enemy forces, while still bringing 66% of his 
>weapons to bear. 

Assuming the ship's weaponry is designed for it and you're playing
Vector, that's trivial - at least unless you're massively out-engined,
but in that case you've got a serious advantage in firepower anyway. 

It's not as easy in Cinematic, but if you have at least thrust-4 you've
got a decent shot at it there as well. If you use assymetric weapon
loadouts it becomes fairly easy. All in all, it's a pretty safe
assumption that the armour will point in the direction of the enemy -
and it's almost as safe to assume that close to 100% of the weapons,
rather than a mere 66% of them, will do so as well.

You also need to remember the threshold factor. This armour is *much*
harder to knock out than screens, both because of the delayed check
(checks as core systems) and because each side checks individually -
which means that the chance of losing *all* armoured sides is extremely
low. Even if you can't repair the armour with DCPs (couldn't see any
note about that in your previous post, but it sounds logical), the risk
of losing all armour protection (assuming 3 or more armoured sides) is
less than that of losing all screen protection.

Let's fill in the rest of the table you began:

>A mass 100 ship has armored 3 arcs (using 3 mass). The 
>effects of an ememy weapon through the armor would be:

Weapon		      Roll (per die)		Survivability increase:
Weapon		 1   2	 3   4	 5  6
Beam		-   -	-   -	1   2p				26%
Salvo Missile	 -   1	 2   3	 4   5			40%
Submunition Pack -   -	 -   -	 1   2p 		26%
Needle Beam	 -   -	 -   -	 -   1n 		100%
P-Torpedo	 -   1	 2   3	 4   5			40%
Nova Cannon	 1   2	 3   4	 5   6			0%
Wave Gun	 1   2	 3   4	 5   6			0%
Fighter (Most)	 -   -	 -   -	 1   2p 		26%
Fighter, Attack  -   -	 -   1	 1   2p 		38%
Fighter, Torp	 -   1	 2   3	 4   5			40%
MT Missile (Std) -   1	 2   3	 4   5			40%
K-Gun, C1	 2   1	 1   1	 1   1			0%
K-Gun, C2	 2   1	 1   1	 1   1			129%
K-Gun, C3	 4   4	 2   2	 2   2			69%
K-Gun, C4	 6   6	 6   3	 3   3			48%
K-Gun, C5	 8   8	 8   8	 4   4			38%
K-Gun, C6	10  10	10  10	10   5				20%
MKP		 -   -	 -   -	 4   8				33%
Scatterpacks	 -   -	 -   -	 1   2			33%
Stinger 	 -   -	 -   -	 1   2p 			26%
Lance Pod	 -   1	 2   3	 4   5			40%
Pulser		 -   -	 -   -	 1   2p 			33%
Plasma		 1   2	 3   4	 5   6			0%

The "survivability increase" is the number of extra shots needed with
that weapon type to kill the target when it's protected by the armour -
ie, it is equivalent to (avg. dmg without protection)/(avg.dmg with
protection)-1. 

Fighters probably shouldn't have their fire degraded by partial armour
(they can after all use secondary movement to get into the right arc,
once they've figured out where that is), and missiles should probably
only suffer the penalty half the time. Even with those changes, it's a
pretty impressive survivability boost - around 30% on average (judging
from the ship designs I've seen to date beams/ pulsers/ stingers are by
far the most common weapons used), though of course it depends a bit on
what weapons your enemy use. If he uses smaller K-guns, missiles,
P-torps etc it gets higher; against a fleet with nothing but PBLs and
fighters it isn't worth anything. A 30% survivability increase is worth
~15% higher NPV.

When the difference in threshold vulnerability has been accounted for,
Level-1 screens affect the survivability by:

Weapon		      Roll (per die)		Survivability increase:
Weapon		 1   2	 3   4	 5  6
Beam		  -   -   -   -   1   2p			21%
Pulser		   -   -   -   -   1   2p			21%
Stinger 	   -   -   -   -   1   2p			21%
Fighters (most)-   -   -   -   1   2p			21%
Fighters (atk)	-   -	-   1	2   2p			14%
Plasma		 1  2  3  4   5    -			36%
No protection against the other weapon types.

Not only does the screen protect against considerably fewer weapon
types (6 of 23 vs 16 of 23, using your categories - though it does
cover the most common ones), but it also gives less protection against
the types screens and armour both protect against due to its higher
vulnerability to thresholds

If the enemy uses beam-style weapons exclusively the survivability
increase becomes 21%; if he uses screen-skipping weapons it gets lower.
I'd estimate an average of 15-18% from the designs I've seen; an ship
with level-1 screens should (on average cost) cost 8-9% more than a
ship with the same hull and weapons but no screen.

OK, so how much should the armour cost? The screen uses up 5% of TMF or
3 Mass, whichever is more; arnouring 3 sides uses up 3% of TMF, minimum
1 or 3 Mass depending on whether the minimum was per side or in total -
you didn't state this in the previous post.

Assume for simplicity an "average" ship - 30% hull, Thrust-4, FTL,
human weapons/screens, no fancy sensors or similar; TMF 100. This ship
costs 340 pts (assuming no FB-style armour, since it can't be combined
with this armour type). Let's further assume that this is the actual
*value* of the ship, rather than just its cost :-/

If this ship is given a level-1 screen, its value increases by 8-9% to
about 370 points. It's TMF goes up to 107 (due to the increased
engines), and its NPV increases to about 366 pts - pretty close to what
it should be.

If it is given armour, its value increases by ~15% to about 390 points.
The TMF increases to 106, and everything *exept* the armour now costs
350 points total. The armour must carry the remainder of the ship's
value, ie. 390 - 350 = 40 pts; it takes up 4 MASS (3% of 106, rounded
up - I assume you clump all sides together before rounding, since you
didn't specify this in the original post and rounding them separately
makes the Mass thresholds even worse), so it needs to cost about 40/4 =
10 x MASS. 

Probably a bit higher, actually - this particular ship started right on
a Mass threshold. Had the original unarmoured ship been TMF 96 instead
- ie., on the other side on that Mass threshold - it only need 3 MASS
of armour, its value increases from around 326 to around 407 pts and
the armour needs to cost 14xMASS to bring the ship up to its real
value. The truth is somewhere inbetween; my guess is 12xMASS for this
toned-down armour version. If you want to bring the value down, you
need to increase the armour Mass.


In my first cost estimate - the one that landed on 20xMASS - I had
assumed that beam dice inflict "-  -  -  -  1  1p" (ie., the armour is
equivalent to level-*2* screens), which means a survivability boost of
almost 70% against the majority weapon type and a value increase of
25-30% (I counted conservatively, so used 25%). For the TMF 100 ship
above that would've made the value around 425 pts, giving an armour
value of 19xMASS in the extreme low case; for the TMF 96 ship it makes
the armour worth 25xMASS in the extreme high case.

Later,

Oerjan Ohlson
oerjan.ohlson@telia.com

"Life is like a sewer.
  What you get out of it, depends on what you put into it."
- Hen3ry