[GZG] How much acceleration do you need to dodge beams and other weapons?

8 posts · Jan 19 2010 to Jan 20 2010

Date: Tue, 19 Jan 2010 00:38:11 -0500

Subject: [GZG] How much acceleration do you need to dodge beams and other weapons?

Assertions:
- Universe with realistic vector movement (s(final) = 0.5 at^2 + vt +
s(init))
- Dodging beams means 'creating a probability cloud of location that
makes beam hits on your ship unlikely enough to justify FB beam results' (and
for other weapons, similar questions)
- No inertial compensators, human partical maximum acceleration
(sustained over a period) of at most about 6 Gs.

Now, before some among you pipe up, obviously this depends on your assumptions
about how many effective shots you can put out in a turn (it may be your
single resolution covers 1000 or 1000000 blasts) and other factors.

I've looked at several time and distance scales and acceleration assumptions
to go with them to figure out how long a turn could reasonably be at different
distance scales. I'm aiming for short turn lengths to justify a granular fire
action and assuming thrust is constant throughout the turn.

Scale A: MU = 1000 km Turn = 5 min Thrust = 1 G per point (requires thrust 2
to get off normal 1 G planet or thrust one with overthrust)

Scale B: MU = 100 km Turn = 3 min Thrust = 0.33 G per point (requires thrust 4
to get off normal 1G planet or thrust 3 with overthrust)

Scale C: MU = 100 km Turn = 2.5 min Thrust = 0.5 G per point (requires thrust
3 to get off normal 1G planet or thrust 2 with overthrust)

Scale D: MU = 100 km Turn = 90 sec Thrust = 1 G per point (requires thrust 2
to get off normal 1 G planet or thrust one with overthrust)

Scale E: MU = 10 km Turn = 1 min Thrust = 0.33 G per point (requires thrust 4
to get off normal 1G planet or thrust 3 with overthrust)

Scale F: MU = 10 km Turn = 45 sec Thrust = 0.5 G per point (requires thrust 3
to get off normal 1G planet or thrust 2 with overthrust)

Scale G: MU = 10 km Turn = 30 sec Thrust = 1 G per point (requires thrust 2 to
get off normal 1 G planet or thrust one with overthrust)

Now.... given what we already know or suppose we might reasonably know
about systems that could grow into SMs, MTMs, fighters, beams, K-guns,
etc.....

What sort of MU scale do you really need to have to justify the existing
mechanics? (Yes, its an incompletely constrained question... some latitude
would be expected in formulating answers....)

I recall reading an article by Marc W. Miller (I think, or maybe Frank
Chadwick) in TNE's Brilliant Lances about the requirements to use lasers in
space. They concluded you'd require gravitic lensing to hit
anything at long ranges (1000 km+). I forget what they said migtht
actually be possible without gravitic control - less than 1000 km I
believe and less than 10,000 km for sure.

If we're operating with short (minute or less) turns and a 10 km = 1 MU model,
is there any justification of missing with railguns, beams, and SMs at ranges
which will be no more than about 500 km?

Or if we're operating with turns of 1-3 minutes and a 100 km = 1 MU
model, does that justification for existing mechanics look good for ranges of
no more than 5000 km?

Or lastly, if our turns are 5 minutes and 1000km = 1 MU, do the mechanics make
sense?

I suspect the later case would be the most sensible. Maybe they are all
equally sensible. How big of a distance [or another way of looking at it is
how much travel time for medium fast (missiles and fighters), very fast
(railguns) or near instant (C beams and particle beams)] do you need to grant
some sort of reasonable miss chances as embodied in the FT rules?

There is no right answer, but there is probably a few 'better' or 'more
likely' answers and a few 'less likely' ones. It may be that today, if we had
working lasers, you couldn't dodge one at up to 500 kms with less than 30 Gs
of acceleration, in which case there is no model that could make this sensible
without gravitic compensation or very, very long ranges.... that's the sort of
thing I'm curious about.

Thoughts?

From: Tom B <kaladorn@g...>

Date: Tue, 19 Jan 2010 02:15:14 -0500