[VV] Agility

I want agile ships to be able to dodge, but high maneuverability in FT doesn't
help a ship evade shots. So let's use Noam's stealth
mechanism (http://nift.firedrake.org/defences/WDA-ECM.htm ) and call
it "agility".

Not decided yet whether to follow Noam's proposal of 0mass / 2pts per
hull + armor, or to treat it as an extra level of Main Drive.

> On Fri, Mar 04, 2005 at 06:57:41PM -0500, Laserlight wrote:

I have often felt that there should be an evasion level based on thrust
from the main drive that isn't otherwise used for manoeuvres - so you
can dodge about a lot, _or_ race for where you want to be...

R

From: "Roger Burton West"  > I have often felt that there should be an
evasion level based on thrust
> from the main drive that isn't otherwise used for manoeuvres - so

That's what I had in mind initially, but should it really be tied to MD? I'm
thinking that a 747 is faster from A to B than a Fokker D7, but not as agile.

> From: "Roger Burton West"

> I have often felt that there should be an evasion level based on

> That's what I had in mind initially, but should it really be tied to

Perhaps, but it's not that simple. For a start, using aircraft as an analogy
is not a good idea because their agility is tied up with
aerodynamics, and guess what -- no air (or other fluid of significant
density) in space. So agility is tied up with the ability to accelerate in one
or more wanted directions, either on command or randomly (as a form of evasive
manoeuvring), and that's what the MD rating quantifies.

Given that a CT with Thrust 4 and an SDN with Thrust 4 behave exactly the same
way in terms of acceleration, turning, etc., it would seem that
MD "thrust" rates acceleration, thrust-to-weight ratio or something like
that -- in which case, provided that a) there are sufficient thrusters
on the ship to push it, and b) the ship structure can stand the jolts, there's
no reason why size should matter in this case. What is important is ship
structural strength, so to provide levels of agility, the evasion level could
be tied to the number of damage boxes the ship has in relation to its Mass;
this sort of brings back the
Fragile/Weak/Average/Strong/Whatever structural classes that Jon ditched
in FB2, but it could be done on a percentage basis or something similar. That
way, if you want your SDN to be able to zip all over the place when fired at,
it can, but you'll be sacrificing something else for the capability, just as
is done now with other systems.

Phil
----
A thought to ponder: Could Batman join the Narn Bat Squad,
  or would he set up the Bat-Narn Squad?

> So agility is tied up with the ability to accelerate in one or more

That *could* be what MD rating quantifies, yes, and that's what I
started out with -- see below. But right now MD doesn't include any
kind of dodge ability, and while they could be part of the same system, I
don't see that they necessarily have to be. I'd like
players to have the option of building e.g. fast-but-clumsy
dreadnaughts, or slow-but-agile destroyers, if they wish.

My initial thought was that a KV ship with 20 Mass and MD4 has a drive costing
4 Mass and 12 points, and it can turn by 4; a Hu'Man ship's drive costs 8
points and it can turn by 2. Therefore 1 level of MD costs 1 mass and 1point
if it's only for increasing or decreasing speed; it costs 1 mass and 3 points
if it can also turn. That means the Hu'Man drive is not simply [4 mass * 2
pts], it actually costs [2
non-turning drive * 1] + [2 turning drive * 3] = 2 + 6 = 8.

You could do the same thing with Evasive Ability, although I confess I have no
idea how much the points cost ought to be.

> The evasion level could be tied to the number of damage boxes the

This looks plausible at first glance, but....there are no hull-box
requirements for high MD.  If a 100-mass ship has 50 hull, it's a lot
more likely to have Thrust 2 than Thrust 8; similarly, a Mass 100
ships with Thrust 13 is rather more likely to have 10-20 hull instead
of 50. You could consider the Mass requirement for high thrust to be at least
partly the hull bracing (and the rest of course being the fins, racing
stripes, chrome, etc).

On Sat, 5 Mar 2005 10:26:05 -0500, Laserlight <laserlight@quixnet.net>
wrote:

> That *could* be what MD rating quantifies, yes, and that's what I

I'm not sure precisely what you mean? Why would a ship be clumsy in a hard
vacuum? How would a ship be agile? I understand what you want
in game terms, but I don't understand what it means in real-world
terms?

> I'm not sure precisely what you mean? Why would a ship be clumsy in

Timestamp A is when a signal--reflected radar ping, or your thermal
signature, or whatever--leaves your ship.  Timestamp B is when the
firer has received and processed the signal, launched his attack and the
attack has arrived at your predicted location. If you wish not to
be hit, you have the interval from A-B to displace your actual
endpoint from your predicted endpoint.

If the firer is shooting from the Z axis, you have to displace your position
in the X axis (which we'll say is the direction you're thrusting with your MD)
or the Y axis (which takes some sort of maneuvering thrusters).

If you only have MD, you can only displace in X -- and will be easier
to hit than if you also had a heavy maneuvering package. Say you have MD4 and
no ability to move in the Y axis, you can be at one of 9
points (-4 through +4).  If you can use all your MD to move in the Y
axis, then you could be at any of, hm, 41 points if I'm doing it right.

On Sat, 5 Mar 2005 19:37:28 -0500, Laserlight <laserlight@quixnet.net>
wrote:

> If you only have MD, you can only displace in X -- and will be easier

Here's the thing, though. If it takes equipment of A mass to displace in X,
then if you wish simillar capability to displace in Y, you will need equipment
of A mass oriented on the Y axis.

So it's simple: You want to thrust in multiple vectors simultaneously,
purchase and instal multiple MDs.

> John Atkinson wrote:

        Well, it is unclear if it means anything in real-world terms.
The way I understand it, an attempt is being made to make an analogy between
WWI destroyers and battleships and hypothetical starships.

In WWI, destroyers were more agile than battleships because they had less
weight. This was done by

> John Atkinson wrote:

Effectively, how rapidly a ship can change its velocity vector and/or
facing, including small perturbations about a mean vector so as to be a more
difficult target for enemy fire. In this context, "clumsy" means that it's
relatively easy to predict where a ship will be by the time weapons fire with
a finite transit time arrives; agile means that the target is more
unpredictable, lessening the probability of incoming fire
hitting -- requiring barrage patterns like heavy flak, for instance,
using more weapons to do a given amount of damage.

> Well, it is unclear if it means anything in real-world terms. The way

And smaller hulls, weapons, etc., all of which had an effect on the overall
balance of forces restricting or allowing the ship to manoeuvre,
but many of which do not apply in space -- waterline length, for
instance.

> Now, if an interplanetary ship:

> [a] uses rockets for propulsion

> the agile analogy might hold. But if either or both conditions are

More to the point, it becomes a matter of how much acceleration a ship can
generate in any given direction, which is what the MD "Thrust" can be
considered as a quantification of. If a ship can generate (and withstand
without breaking) a certain acceleration, then it doesn't matter how big or
massive it is; what is important is the direction(s)
that the ship can accelerate in, and how fast -- that is, how big is the
sphere of possible locations for the ship given a known transit time for
weapons fire.

Phil

Nyrath said:
> The way I understand it, an attempt is being made to

No. My point was that if you have the capacity to thrust in a direction other
than your main drive axis, you become a less predictable target. You could
have the same ability on SDNs, if you like, you just need a bigger drive. (I
don't think this would work equally for bigger ships IRL because the thrust
would not be applied to all points of the ship at the same instant, so bigger
ships would
be more likely to have something break -- but FT doesn't account for
that).

> Here's the thing, though. If it takes equipment of A mass to

Except a) MD is for extended continuous use, and "dodge drives" would be more
for high-thrust / low-duration bursts. The "dodge drive" would change
your position by less than one mu over a turn.

b) MD, even MD13, doesn't make your end position more unpredictable
WRT incoming beams, etc.--if you happen to end up in range and arc,
you get hit the same no matter what your MD is.

So you need something other than MD.  Mass 5%/level seems reasonable
although I suspect that 2 points/mass is too cheap.

I also wonder whether dodge actions could come before, after or simply modify
the actions of SMs and all that.

since FT is WYSIWYG as far as missiles, I guess it would be better to allow a
dodge move, but it rankles
me from a 'pure vector' standpoint. :-/

> --- Laserlight <laserlight@quixnet.net> wrote:

Jeff "My dice hate me!" Fearnow Gaming to keep War out of RealTime!

"'DESTROY THE WITNESSES!!. Chaffing aside, I have no answer: I Excrete Sour
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