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Re: [FT] Hardened Systems

From: "Oerjan Ohlson" <oerjan.ohlson@t...>
Date: Thu, 14 Jan 1999 19:07:41 +0100
Subject: Re: [FT] Hardened Systems


----------
> Från: Sean Bayan Schoonmaker <schoon@aimnet.com>
> Till: gzg-l@CSUA.Berkeley.EDU
> Ämne: Re: [FT] Hardened Systems
> Datum:  den 14 januari 1999 05:12
> 
> [snip]
> 
> >For systems (weapons, FCs, screens etc) 50% is way too much. In these
> >cases, hardened systems should have 25% extra Mass and "softened"
ones
> >(ie, systems which add 1 to all treshold rolls, so they fail the
first
> >check on 5+ etc) should get a 20% Mass rebate. The cost per Mass
> >shouldn't change.
> >
> >(I can give you the statistics supporting this as well, but it'll
take
me
> >several evenings to type it in :-(  )
> 
> Did someone say statistics?
> 
> Cumulative chance of loosing the system
> 
> Regular system:
> 1st: 16%
> 2nd: 50%
> 3rd: 100% (note that this doesn't mean it's automatically gone - it's
just
> statistically gone)

<sigh> OK, a very compacted version of the correct statistics:

The cumulative chance to lose a system is

1st: 16.7%
2nd: 100% - 83%*66% = 44.4%
3rd: 100% - 83%*66%*50% = 72.2%

ie, the probabilities are multiplicative and not additive.

If you count the average "life-time" of the system, you'll find that on
average it goes down when the ship has lost 2/3 of its hull points for
an
ideal ship (ie, one with an equal number of hull points in all four rows
and no armour);
for real ships (armoured, etc) the figure usually lies somewhere between
2/3 and 3/4 of the hull points.
 
> Hardened system:
> 1st: 0%
> 2nd: 16%
> 3rd: 50%

Correct values:

1st: 0%
2nd: 16%
3rd: 44.4%

with an average "life-time" for the system of 84% of that same ideal
ship's hull points. 84/66 = 127%, so it is usually sufficient to round
the 25% extra Mass up after you've added all the hardened systems'
masses
together.

For real ships (I've used all the FB designs and John Atkinson's NRE
ones
for data), the hardened systems have a "life-time" varying between 122%
and 127% of the standard one; 25% is very close to the average for those
ships.

So, if you get ~25% more use out of the system, the mass penalty should
be 25%. Simple as that :-)

> 2 x Regular system:
> 1st: 8%
> 2nd: 25%
> 3rd: 50%
> (But you also have the advantage of being able to use both until
they're > gone!)

I'm not even sure what you mean here. The chance to lose one out of two
arbitrary systems, or the chance to lose two systems? Either way you're
wrong <shrug>

Correct table (not that it is really relevant - the average percentage
of
your systems that is up at any given treshold level is the same no
matter
how many systems you're looking at):

Standard system:

Treshold:		Chance to lose...
		1 system	2 systems
1st		  27.8%     2.8%
2nd		  49.4%    19.8%
3rd		  40.1%    52.2%

Hardened systems:

Treshold:		Chance to lose...
		1 system	2 systems
1st		     0% 	      0%
2nd		  27.8%      2.8%
3rd		  49.4%     19.8%

> So a 50% mass increase is actually not too far off.

Yes, it is. I've played too many battles with this type of hardened
systems not to know this :-)

Try it out in a battle and you'll see. With a 50% mass penalty for
hardened systems, the ship has to be very lucky or do some really
brilliant flying to win.

With a 25% mass penalty for hardened the forces are almost identically
balanced - well enough that other balance problems like screens and
random initiative overshadow any unbalance caused by the hardened
systems. The same applies for weakened systems with a 20% Mass rebate.

However the above doesn't apply for engines and fighter bays. The
fighters aren't much affected by if their bay survives or not until
their
endurance runs out (by which time the battle tends to be over... and it
is very rare in my experience that many fighters live to burn out all
their endurance anyway), and the effect of engines on combat outcomes
isn't anywhere close to linear :-/

Because of this, the +25%/-20% hard/weak systems can't be allowed for
engines and fighter bays.

Best wishes,

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

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