> One more question on this: will FB2 cover revised Stealth/Sensor/ECM,
Okay, we're going to design The Stealth/Sensors/ECM System. The
objective is to develop something which is simple & easy to use, while giving
a flavor of stumbling around wondering where your targets might be.
Definitions first:
Stealth: is to keep you from being seen in the first place. Powering down your
ship helps a lot; having systems powered but not in use (such as drives,
screens, fire controls) helps a little. Making an active sensor scan ruins
your stealthiness. Bigger ships are less stealthy than smaller ships.
Sensors: Gathers information, ranging from:
a) none--"there's nothing out there"
b) bogey--"we can't pin it down, but there's something there"
c) range, vector, firing solution d) ship class ID
e) current status/damage estimates
Sensors come in three classes (BES) and two modes (Passive/Active)
Basic
ranges P/A are 36"/54".
ECM: can't keep the enemy from knowing you're there, but it may keep him from
knowing what you are. It may spoof missiles.
Next round (after caffeine) will toss out some proposals.
Here we go again ;-)
> Stealth: is to keep you from being seen in the first place. Powering
OK - fine, though ship size may be insignifigant compared to other
factors. Emissions are the key, not size.
> Sensors: Gathers information, ranging from:
Perhaps this should read "We have no idea" as they don't know what's there.
> b) bogey--"we can't pin it down, but there's something there"
I feel that c & d should be combined to KISS
> e) current status/damage estimates
Possibly unnecessary with current rules.
I favor the following:
Level 0 - no info
Level 1 - detection, number of ships in sensor range
Level 2 - approx size class, place in log based mass scale
Level 3 - all info
> Sensors come in three classes (BES) and two modes (Passive/Active)
Basic
> ranges P/A are 36"/54".
Basic should be inherent to all vessels to prevent the necessity for redesign
of current vessels.
After that, I rather like the idea of making them in classes, just like beam
batteries.
Then your ECM and ECCM "fire" and score "hits" which can give
bonuses/penalties.
> ECM: can't keep the enemy from knowing you're there, but it may keep
These could be some of the effects.
> OK - fine, though ship size may be insignifigant compared to other
My off-the-cuff suggestion is to take the cube root of the ship's mass,
square it, and divide by whatever constant you like (which will be determined
by how broad a spread of factors you wish). If you pick, say, 10
as your constant, then a mass 64 cruiser would have a factor of 16/10 =
1.6,
round to 2. Square of the cube root is to represent the ship's
cross-section. I think that allowing both positive and negative
construction stealth modifiers would then let you quanitify how well you
designed your cross section.
However, it might be better to say "you get +1 to be detected for every
(level of screen active x 50 mass) and for every (thrust used x 50 mass)" or
something similar.
My thought is that bigger ships will emit more and thus should be easier to
detect.
> b) bogey--"we can't pin it down, but there's something there"
OK. Main thing I want is the ability to maneuver against targets which are not
yet identified. "Is that a battlecruiser or a frigate?" "I don't know, sir,
we're just tracking the thrust plume."
> I favor the following:
The max should be "details of enemy damage" as in "sir, their screens are
down!"--note that this should come AFTER "firm ship class ID".
> Basic [sensors] should be inherent to all vessels to prevent the
Of course.
> After that, I rather like the idea of making them in classes, just like
Next step: work out the mechanism for this.
> Laserlight wrote:
> >Then your ECM and ECCM "fire" and score "hits" which can give
How about using a ship FCSs for detection. Each one assigned to detect rolls
as a Class 2 beam. Enhanced and Superior Sensor Array (as per MT) would rais
this to Class 3 and Class 4 respectively.
Chan
> How about using a ship FCSs for detection. Each one assigned to detect
FCS are a very different beast than a sensor. A FCS is a pencil beam focussing
a LOT of power on a single target. A Search system is sending
that energy out over a very large area. Physically/Mechanically they
are very different.
> On Wed, 2 Jun 1999, Phillip Pournelle wrote:
> >How about using a ship FCSs for detection. Each one assigned to
i hear this a lot, and i'm always a little suspicious. sure, that's how modern
FCS and surveillence sensors work, but how do we know that that's
how future space-navy kit will work? not that i'm saying it won't:
personally, i think it probably will, but are we so sure?
tom
> Phillip Pournelle wrote:
> FCS are a very different beast than a sensor. A FCS is a pencil
But as everybody is going for Phased Arrays, with smart power management, this
may well change.
Basically, with a search radar, you want a long dwell time, and a broad
beamwidth, to maximise the chance of getting a return high enough above
background to be significant. So out of 10-20 "paints" or pulses, you
might get 6-7, vs a background of 2-3. Since we're talking about EM
sensors, the speed of light is actually quite a limiting factor: you
want to put out maybe 10 pulses over 1/100 of a second, which means
your range is limited to 3x10e5/2 metres if you want time enough for
each pulse to go out and come back before the next is sent. Using pulse
compression, and pulse frequency variation can help, but jitter the PRF (ie
change the tinme delay between pulses) and it gets worse.
With a FC radar, you need a very high power (to burn through jamming at its
stongest point), and more particularly, a high degree of accuracy, typically
on the order of cm. FC radars are typically thin pencil beams,