I apologize for including the complete text of two previous messages here.
> From: "Mark F. Cook" [email removed]
> Subject: (1715) Help!! Trade & Commerce nightmare!
>
> Well, I've put it off for as long as possible, but I've finally had to
> bite the bullet and dive into the Trade & Commerce section of the MT Ref's
> Manual. It's even worse than I thought!! Help me out here folks, 'cause
> I've got a TON of questions. (Well, a couple Kilos, at least :-)).
>
> Starting with Part 5 "Freight and Cargo" (pg. 50), does the AVAILABLE
> LOTS table apply to Freight, or Cargo, or do you use it once for each?
> Also, how do you determine lot size for freight? The note that refers
> to "Lot Size" only mentions cargo.
My interpretation of this, and I don't have my rule book with me, is
that you would be correct in assuming that you are to use it once for each,
cargo, and freight. Determine lot size for freight using the same table.
This brings up a comment I made months ago. According to older versions of
rules that used essentially that same lot size table, the lot sizes for major
and minor cargoes were 1d6*10 and 1d6*5, not 1d6+10 and 1d6+5. Since the
latter means that a typical 600+ ton ship can only fill its hold at a Pop9+
world, heading for another Pop9+ world, I have been using the former system.
>
> Next comes the REAL mess: cargo cost. As nearly as I can tell, the rules
> which govern the determination of cargo cost (to the speculator) on pg. 53
> MAKE NO ALLOWANCE FOR CARGO TYPE. This means that a 100 Kl. lot of ferrous
You've grasped the rules firmly, I see, and discovered the thorns in the
process.
> metal ore costs the same as a 100 Kl. lot of electronic parts, which costs
> the same as a 100 Kl. vehicle, which costs the same as 100 Kl. of TL-15
> mud! It's all based on volume (or weight), and modified by trade code,
> tech level, and source world starport type. What a crock of SH*T! When
> I saw the spec. cargo entries on pg. 13 of "Knightfall", my initial
> reaction was, "Yah! That's how it's suppose to look!" Unfortunately,
> you can't get there from here.
If you have Knightfall, you can look up the quick fix system, not perfect,
subject to your own common sense modification, but available between now
and next week.
>
> What's a ref to do? (BTW, I need answers BEFORE the middle of next week.
> Otherwise, James and Richard's new characters in my campaign may be standing
> in the unemployment line. ...and I think one of them bites!! :-))
>
> Mark F. Cook
---------------------------------------------------------------------
> From: George William Herbert [email removed]
> Subject: (1705) Fixing Maneuver Drive Physics...
>
>
> I've been working on a fix for justifying the volume-based maneuver drives...
> It goes something like this:
> Maneuver drives (not grav thrusters) don't actually produce thrust
> or force. What they do is distort the local gravity field...not just play
> with it like lower tech grav, but actually forms a gravitational gradient
> (volume of warped grav. volume is proportional to the maneuver drive
> volume...) around/within the ship. The 'thruster plates' garbage can be
> explained away through pseudogobbldeygook 8-) . The Inertial Compensators
> take this field (which should be uneven, stronger closer to the drives...)
> and even it out so that everything in the ship doesn't fall towards the
> front 8-) .
>
> Comments? Suggestions? Let's hear 'em, I'd prefer not to have to junk the
> current rules, even if they need revision (yay metlay).
>
> - -george
My suggestion for this is as follows. I haven't got my rule book with me, so
I'm winging it on numbers. Suppose we did this: The TL9 grav spaceship
drives are functionally equivalent to the StdGrav of the smaller vehicles
table. I'd make the assumption that power consumption remains constant
per ton of thrust, but size and weight can be decreased in some sort of scale
efficiency like the power plants. This means that a Grav Maneuver unit
produces 650 tons of thrust for the 65MW of input power. You could calculate
the minimum "economy of scale" size from the 1G drive for the 20 ton hull...
however many units that size takes up is where the crossover point for
advantageous size/weight would be. Now, for a spacecraft of TL9-10, things
become very easy. You merely calculate a thrust, same as always, and
divide by the LOADED weight of the vehicle to get an acceleration, same as
for any smaller grav vehicle. If your thrust isn't equal to the local gravity
times your loaded weight, you can't land or take off from that planet.
Simple enough, right?
Thrusters would then work like this...they simply become improved grav units
that can work away from a gravity well by some double talk I don't want to
worry about right now. The price you pay for this ability is increased power
consumption...70MW for what 65MW of grav would do. So 13.5 kl of thrusters
would weight 35 tons, consume 70MW and produce 650 tons of thrust not reduced
by distance from a planetary gravity well. To keep everything consistent, you
can decree that the minimum size these things can be built at is the one that
corresponds to 1G for 20tons, and if you want to stick that (6kl??) unit
and the power to drive it in a 13.5kl vehicle, go ahead. Multiply your
thruster units by 650 tons, divide by the LOADED weight of your vehicle and
you have your maximum acceleration. If your thrust is less than your loaded
weight, you don't land on planets with standard gravity, and so forth...
Still simple enough, right?
If you actually do the calculations involved for a couple of examples of ships
with minimum armor, you'll find that the accelerations work out to be close to
the maneuver drive rating, which implies that that is how they were worked
out in the first place.
Anyway, that's a simple fix that will enable you to dispense with any really
bizarre explanations of why the drives were sized the way they are.
As far as inertial compensators go, I have always subscribed to the theory
that they are merely grav plates mounted in different directions, and tied in
somehow with the nav computer so as to provide a dynamic cancellation of
of the acceleration effects of the maneuver drive. (e.g., if you have a
6-G maneuver drive burning full out at the tail, in normal physics, you will
be standing on the back wall at six times your normal weight. If you have
1-G grav plates in the floor, you will feel a "gravity" that is the resultant
of the addition of the two vectors. If you put six G grav plates at the nose,
that vector cancels the 6-G maneuver drive vector, leaving you with a
comfortable 1-G toward the floor. Did everyone follow that without the
diagrams? ) This probably means that the power consumption of the
compensators should be tied to the size of the maneuver drive, and should
usually be more than the power consumption of the grav plates.
AGILITY: A NEW SUBJECT
Pursuant to the above discussions on maneuver drives and inertial
compensators, I'd like to say a few words about the game's concept of agility.
To be brief, it's another crock of...spoiled butter. The only use of agility
in the game is in combat, where it represents the difficulty of hitting the
ship with a weapon, and I'd like to look at that for the moment. Agility
is tied to the ship's mass, which is good...it represents the difficulty
of shoving it around in space, so that's rational. It is calculate by
"dividing the excess energy by the UNLOADED weight of the ship etc.". I'd
prefer to see this based on the actual weight of the ship, which is usually
something between the loaded weight and the unloaded weight, unless you have
a cargo hold full of metal ingots...but that's not the problem. The first
problem is one of definition. What is excess energy? I've always figured
that it was what was left after everything EXCEPT THE MANEUVER DRIVE was
powered, since it seemed that agility should be a function of maneuver drive.
That being the case, I'd also always assumed that there was a cap on the
energy used for agility equal to the maximum that your drive used. (If your
drive consumes 65MW, I'd hate to see what it looked like after you ran 2000MW
into it to increase your agility...if those 2000MW aren't going into your
maneuver drive, then you should be able to buy "agility increasers" of some
sort, but that is a can of worms I'd rather not open just now.)
The second problem is that, as far as I have ever been able to tell,
normal inertial physics are supposed to hold true in the Traveller universe
in everything not related to Jumping.. Right? So the MT definition of
agility as "ability to change your heading" is meaningless. If I have a
ship with a movement vector --------------------------------------->
like that, and I start up my maneuver drive <- like that, except at a small
angle, my vector, which is what people are using to guess where I'm going, to
put unfriendly laser beams etc in my path, is going to change very slowly.
Some nebulous ability to change my heading (What, the direction my ship is
pointing??? If I rotate 180 degrees about my present course, I'm still
flying very fast tail first across the universe) is not going to prevent
somebody from predicting my course well enough to get a missile within
intercept range.
As a first approximation, I'd say that your "agility" rating ought to be
equal to your acceleration rating, as figured above where it depends on
mass, minus whatever loss of acceleration you have by shunting power to your
weapons instead of your engines, PERHAPS modified by some measure of your
rotational inertia if you want to be a completist (a spherical ship should
be able to rotate faster to bring the maneuver drive to a new heading than
a needle shaped ship.)
Now, all of this brings up another question regarding space combat...do energy
weapons actually aim for an enemy ship, or does the firing vessel attempt to
predict the location of the target, and then spray the beams around the
estimated target locus in an attempt to get a random hit(s) by volume of fire?
In either case a "realistic fix" to the combat system should account for
speed of light lag on detectors (at a greater distance the future position
of the target becomes more uncertain as your data is more out of date) and the
relative speeds of the two vessels (again, adds more uncertainty to the
location of the target. The difference would be that in the first case, you
could gain something in defensive ability by using thrust of whatever source
to shove you from "side to side" along your base vector to throw off the
enemy's prediction programs, or for that matter simply pulse your maneuver
drive in random power levels at short intervals, (Say 1.5 to 2.0Gs in a 5
second pattern--better have inertial compensators or the spacesickness will
be fierce ;-) ), but in the second case that would be less
effective, more like trying to dodge a shotgun blast after it has had time to
spread. In either case, a missile that retains maneuver capability for the
final interception would be less affected by "small" movements on the part
of the target. Missile hits, though, should possibly be strongly affected by
relative motion...if your missile is closing at 6-G with a high speed on a
vessel headed straight at it and also accelerating, it would have less
time to use it sensors and drive to effect the final interception, and would
therefore probably be more likely to miss.
HULL ARMOR, CONFIGURATION AND DAMAGE POINTS
A few more ideas to think about for the vehicle system redesign. As
Scott Kellogg pointed out, the results you get when you apply current
technology to the spacecraft minimum armor requirement of "40" can be
ludicrous. Why not do away with it entirely? It would involve the following
changes to the overall game system. The spaceship combat system is based
on the High Guard system, with the old armor levels 0-9+ being replaced by
the new armor levels 40--, with each old "1" equal to "3" new for combat
effects. At a minimum, it would need to be reconfigured with a new base
value other than "40", at a maximum be replaced by something fully compatible
with whatever ground vehicle combat system is adopted. An absolute minimum
for spacecraft would still need to be established, whether it was based on
armor needed for radiation resistance, structural strength needed to withstand
the effects of the maneuver drive (in which case it could be a sliding scale...
if you wanted a "space only" craft with a max thrust of .005G, you wouldn't
need much strength), or structural strength necessary to contain a
one-atmosphere pressure of breathing gas, or some other measure...say heat
shielding minimum for reentry. ('Course grav vehicles can reenter very
slowly--as long as it isn't against a planetary defense system.).
As it stands now, an airframe configuration buys you maximum streamlining,
but we should also be able to set it up so that you can build a grav vehicle
using the new equivalent of the Vehicle Design Sequence to use dynamic lift
provided by wings or a lifting body hull. If your 2G combat speeder had wings
to hold it up, it would be a 3G combat speeder...(Which reminds me obliquely,
that grav vehicle performance should really be recalculated based on local
gravity, just as aircraft performance should be recalculated based on gravity
and air density.< and composition, to be extremely technical>). Naturally,
I expect this would cost more, but it wouldn't be that tough to add.
Contrariwise, at low grav-available tech levels, it might be advantageous for
some purposes to put in a grav module just large enough to hold up a craft, and
then use jet engines, or even propellers, for thrust. Also, we should
possibly consider setting things up so that streamlining has more of an effect
than being a top speed limiter. If I push a brick with 10 lbs of thrusts,
it won't got as fast as a cone of equal weight pointed the right way. I think
this could be done simply enough by having a little table, no more complicated
than the ground pressure vs P/W to calculate off road speeds.
I think vehicle damage should be based on something more than volume...I
realize that it was done that way for simplicity's sake, but perhaps a rating
based on unloaded mass would do better. You need to calculate that number
anyway, and I think that it would be a more accurate "One number guess" of
the comparative damage capacities of, say, a hot air balloon and an M1 tank.
Enough for now.
Rob Dean