
-------- TML Message #1915 --------

Archive-Message-Number: 1915
Date: Mon, 3 Dec 90 11:28:36 -0500
From: "T. L. Hayes" <al646@cleveland.freenet.edu>
Subject: Loose Change



My two cents on a variety of things -

"Robert S. Dean" <rsdean@crdec8.apgea.army.mil> says:

>to offend anyone.  As you are all aware, the scheduled MegaTraveller robot book
>isn't on any DGP schedule I've seen lately, so anyone wanting to use robots is
>forced to limp along with Book 8.  The following is my attempt to lay out a
>Book 8 robot in a format similar to the current "standard vehicle" format,
>hopefully with enough info that anyone could "reverse engineer" the design if
>necessary.  I did this a while ago, so I *think* that I laid out any components
>in the Referee's Manual Vehicle system according to that system rather than
>Book 8, and revised the Book 8 configuration numbers to match the vehicles.

Personally, I like this format.  It adds uniformity and readability.  I would
like to see more robots.  No offense to vehicle designers but I, at least
for now, have more use/need for robots and small starships (less than
2500 tons).  My players are not interested in military activity and large
starships are out of their reach.

Speaking of scheduled releases, has anyone heard anything about the new
adventure that's coming out (soon?) called "On the Edge" (I think)?  It
set in the Spinward Marches but usable anywhere.  Its due out in '91 and
that's all I've heard so far.

About Trade/shipping:

With respect to Jim Baranski's posts (1869 and 1879) I agree.  It seems to
me that a planet's import/export market will be driven by population,
tech level, and trade classification.  Large populations are needed for the
work force to mine raw materials, to manufacture finished products, to 
grow food/livestock, or to consume finished products and food/livestock.
The tech level will influence the desirability of an item.  Why use TL8
computers if you could get TL15!  The trade classification indicates that
planets speciality or needs.

The comment that all planets will have raw material (unless it has been
used up already as may be the case on an old planet like Terra) is 
generally okay but you can have planets/systems that are low in heavy 
elements.  These systems will not be origin worlds for life (since life
is filled with heavy elements like iron) but may be colonized (why?).
If the system is a second or third generation system (ie was formed very
early in the life of the galaxy) there would be little heavy elements
present and they would be deep in the core of the planet.  Heavy elements
all come from stellar deaths (basically) so early on few stars would have
died so forming systems would be poor in heavy elements.  A planet in this
predicament would probably be poor and have to import *everything*!  On the
other hand, the gas giants of such a system would be very pure.  They 
could be the source of some of the cheapest fuel in the Imperium!

Looking back over what Jim wrote and what I just wrote brings up an
interesting point.  Trade is using *during* the game that means it needs
to be a quick resolution type system.  Your players don't want to sit
around on their hands while you determine what a planet has to offer.
Maybe there should be a simple, reasonable system for routine use or for
players who aren't interested in trade as the main theme for a game and
an advanced, expanded version for times when that is called for kind
of like the starship operators manual.  For the streamlined version
maybe a variation on the MT version or the Classic Traveller version
could be used.  Just make a couple of patches to the most glaring holes.

About the TDR ship design rules by Rob Dean:

>       For space faring craft, normal acceleration now becomes
>       thrust/weight.  If this value is less than one, the craft cannot
>       lift off from a standard gravity planet. For operations near a
>       planetary surface, figure speed of spacecraft based on
>       (thrust/weight)-1 to account for power required to maintain lift.
>       Agility is equal to the acceleration available after all other
>       systems have been powered.

What about Cargo?  Do you mean to imply that some average weight should
be assumed for acceleration calculations or should you recalculate with
each cargo run or ignore cargo?  Otherwise (after a brief once over) it
looks good to me!  I am glad to see that you didn't start over from
scratch but rather fixed the existing system.  I don't want to learn an
entirely new game, I just want some of the holes filled!

Adrian Hurt writes:

>>                                               Are there other ways to land
>> ships?  Are there reaction drives that are not destructive?  Some scenarios
>> have space ports have gravitic landing platforms, and scorched earth
>> wilderness landings.  I kind of like that.
>
>Reaction drives are bound to be destructive.  It's all down to Newton's 3rd
>law.  Without doing sums, force pushing ship up = force pushing ground down.
>If mass of ship = huge, force pushing ship up = lots, so force pushing ground
>down = lots, so being under the ship isn't a good idea.  Gravitic landing
>platforms - you mean a big repulsor that lets the ship down gently without
>the ship doing anything?  Nice idea, and I expect the ship gets charged some
>CR for it.

Two things: First I been looking in the various MT books and have come to
the conclusion that when they say "reactionless" they mean using no
reaction mass or no exhaust.  A variation on anti-gravity technology or 
the like.  Second anti-gravs are reaction drives (they push against gravity)
but aren't destructive (no flatten houses or people when one flys by). 

TLH

- - --
T.L.Hayes                  |
MIT/Lincoln Laboratory     |
Lexington, MA              |

-------- TML Message #1916 --------

Archive-Message-Number: 1916
Date: Mon, 3 Dec 90 02:14:26 -0500
From: Mark Gellis <f3w@mentor.cc.purdue.edu>
Subject: Re: Trade and Fusion Drives

On the subject of trade, etc., one thing that has always been a failure
for me with sf games is that they mostly ignore the real impact of space
industrialization.  Even if only one percent of a planetary population
likes being in space, what will happen in the long run is that their
children will grow up thinking of living in habitats as natural, so they
will expand into space rather than go back to a planet.  

The resource base is pretty simple.  A fully developed solar system could
have five or ten billion people on a planet, but hundreds of billions living
in habitats near asteroids, around gas giants, or in the cometary halo.

The "geography" of such solar systems would resemble an ocean full of 
archipelagos, hundreds of large groups of habitats, each centered around a
resource base like an asteroid.  Each archipelago might have thousands of
individual habitats (L5-type city-states with anywhere from ten thousand
to ten million people apiece...my own estimates are a low end of 40,000
and a high end of 1,000,000, but you could build larger or smaller and 
get away with it).  Trade in such a society would be limited by the
demands of physics.  Fusion-powered spacecraft will be very cheap once
we get fusion under control (matter-antimatter is more fuel efficient,
but with fusion the fuel is hydrogen, which is very plentiful)...well,
cheap in relative terms, spacecraft will still be expensive, but fusion
drives will be very efficent.  For most ship designs, most of an 
inner solar system (Earth-to-Ceres, etc.) will be a matter of a week
or two of travel (assuming you don't use jump drives for intrasystem
travel) and a few weeks to the outer system (Earth-to-Neptune, etc.)
and several months to several years for parts of the cometary halo.

In other words, sailing ships of the eighteenth and nineteenth centuries,
and, to some extent, steamers of the nineteenth and twentieth centuries.
And a society that would resemble, in some ways, Europe, if it were
broken up into physically separate power blocs...or what the world
might be like the centers of culture were as divided as they are now
(Europe, America, China, etc.) but we only had 1800-1900 sailing/steaming
technology for travel.

By the way, I use a figure of 1 million for the Isp for fusion drives 
(about what the Daedelus project people suggested), and 20 million for
matter-antimatter drives (which is a bit more than what Charles Sheffield
suggests, but easier to deal with in games terms than the 18 million he
proposed).  (Much easier to do the numbers this way, and it does not
affect the realism of the game in any significant manner.)  The average
spacecraft in my game world uses 30% of its mass for fuel, which, at 
one gravity, gives it 352,000 seconds of thrust, which means spacecraft
will go to about 1,600 km./sec., and then coast at about one billion km./
week until they are ready to slow down, and then slow down (this leaves
a 10% reserve of fuel for mid-course corrections, etc.)

I will admit to vanity when I say this, but I really like the way I have
worked this out because it means that every single fully developed solar
system (Tech 11 or Tech 12 or more) is an enormously exciting place, with
the equivelent of dozens or even hundreds of worlds in every solar system.
Imagine, fellow GMs, the kind of intrigues you can have, with dozens of
powerful governments and megacorporations vying for influence, vying to
control the lives of half-a-trillion people, and this is what goes on in
every single solar system in your game world.  (And, if you like complex
and paranoia-inducing plots, remember that at this level of complexity,
you have governments and corporations so complex, and with so many levels
in their hierarchy, that different branches will be trying to screw each
other over...)

Enjoy.


-------- TML Message #1917 --------

Archive-Message-Number: 1917
Date: Mon, 3 Dec 90 11:59 EDT
From: METLAY@vms.cis.pitt.edu
Subject: Why Armor-40 is minimal for starships


To the best of NASA's knowledge, the LDEF was never hit by anything larger
than a pinhead in two years of flight orbiting around the Earth. To use
this, and other data from man's limited exploration of his universe so far,
to make guesses at how a Traveller starship must be armored, isn't a good
idea. In my opinion, the 40-minimum should be preserved in any economically
viable ship design, for essentially one reason: high-velocity fragments.

The odds of getting hit by an asteroid larger than a sand grain on a trip
through the Asteroid Belt in our system at relatively low speeds (Voyager
took years to get to Jupiter, you do the math) are infinitesimal. But what
about a ship that plies a thousand different star systems or more for well
over a century, often at near-relativistic speeds? At a rough guess, once
a year or so it'd go through a Trojan point or meteor swarm in a hurry, and
run a very real chance of something fairly big striking fairly fast. And if
you don't think a ten-gram impact getting turned into energy would hurt a 
ship with a 1-inch-thick skin of aluminum alloy plating and honeycomb core
(std. NASA design), think again. The entire starship combat system of another
game I admire intensely, ALBEDO, is based on what happens to a ship if a half
dozen small chunks of metal impact on it at near lightspeed. (In fact, if one
were to follow the economic logic of Dow Rieder's Robot Drone Missile Swarm
system, the MT universe and ALBEDO universe would have identical combat 
strategies!) Starships don't put that much of their cost in hull armor; even
factor-40 bonded superdense is a pittance compared to the computer and drives.
It's good insurance on the part of the manufacturer to see to it that a random
strike won't cripple the ship and kill the crew; so I would say that the 40
rating is not a PHYSICAL requirement for construction, but a LEGAL requirement
for minimum safety that an underwriter would insist on before financing the
ship's construction. You can build an airliner without firefighting equipment
or onboard oxygen or advanced IFR gear. You'll save a bundle. But would you
be able to find a buyer?

Just my two cents' worth. Thanks to Dow Rieder for his input on this.

metlay

PS> TDR will NOT support discussion of topics with a separate mailing list.
As long as what gets talked about here eventually finds its way into real
TDR submissions, then the TML is a good place to discuss these topics: 
whether or not they find their way into TDR is the TDR group's business; 
whether or not they are interesting and stimulating, and encourage thought
and development of our beloved game, is EVERYONE'S business.

-------- TML Message #1918 --------

Archive-Message-Number: 1918
Date: Mon, 3 Dec 90 12:04 EDT
From: METLAY@vms.cis.pitt.edu
Subject: Addendum on my PS to my last post: About TDR discussions


I will not make Mark retract his post about TDR SIGs and internal discussions.
Nor will I retract my statements about discussion on the TML. I believe they
both have their place; TDR SIGs for seriously-committed people who are actively
trying to help hammer out rules, and the TML for discussions among those who
wish to volunteer ideas and so on in a noncommittal way. Registry on a SIG is
a player's statement that he or she is serious about contributing actual 
material; submissions to TDR itself are the end result of this. So we have a
multi-level discussion going on, with no lowering of involvement at the TML
level. How's that sound?

metlay

-------- TML Message #1919 --------

Archive-Message-Number: 1919
Date: Mon, 3 Dec 90 13:01:46 -0500
From: wrgate.wr.tek.com!tnc!m0068@uunet.uu.net
Subject: Designs from Scott Kellogg 12/2/90

From: m0068@tnc.UUCP (Stephen D Smith)
Organization: personal mailbox at The Next Challenge
 
*********************************************************
I have no access to e-mail so you will not be able to 
reach me very easily and there will be long gaps between
my having access to any comments to any designs or ideas
you might have but I would appreciate it
 
      Scott Kellogg      (703)-836-8352
      1202 S. Washington St. #107
      Alexandria, VA, 22314
*********************************************************
 
Patrol Submarine TL6 "Gato" Class
 
CraftID:  Patrol Submarine, Type SS TL6, MCr 62.32605
Hull:     (225/563) Disp=160, Config=3SL, Armor=9B, Unload=577.09t,
          Load=1645t, Dived=2160t, SafeDepth=90m, CrushDepth=135m
Power:    (3/6) 27 Mw Imp IC, Dur=40/120 Snorkel installed
          (6/12) 18 Mw Battery, Dur=1hr full power, 8hr @ cruise,
          12hr w/no engines
Loco:     (8/15) Twin Screw, DiveTop=17Kph, DiveCruise=6kph,
          SnorkelTop=21kph, SnorkleCruise=16kph, SurfaceTop=36kph,
          SurfaceCruise=27kph,
Commo:    Radio=Reg*2
Sensors:  Active Audio, Passive Audio*10, Environmental Sensor,
          RDF, Headlight*2, Periscopes*2
          ActAudScn=Form    ActAudPin=Form PasAudScn=Form 
          PasAudPin=Form PasEngScn=Form
 
Off:            HPoint=1 (Deck gun mounted on forward deck, HMGs
                on conning tower)
 
                           Pen/           Max         Auto  Dngr
          Ammo   Rds  Attn  Dmg     Range  Tgts  Spc   Sig    ROF
8cm HV  KEAPER   100    28   10  Dist(16)     -    -     M     10
            HE     -    14   12  Dist(16)     -   20     M     10
HMG*2        -  2000   6/3    3  VLong(1.5)   3    -     H     80
 
533mm Torpedo Tubes*10      (6 Forward, 4 Aft)
                                 Max         Chance
                Rnds  Warhead  Range  Speed    Hit%
Torpedo Mk XIV    26    230kg    8km  58kph     40%  (From Harpoon)
 
Def:            DefDM=+2
 
Control:  Computer=Model1, Enhanced Mechanical=8700
Accom:    Crew=80, SmallStateroom=6, Bunks=73 Env=Basic Env, Basic
          is, Extend is, AirLock*3
Other:    Fuel=960Kl Diesel, Forward torpedo Mag=27Kl; 18 rds, Aft
          Torpedo Mag=12Kl; 8 rnds, 80mm Mag=1.4Kl; 100 rnds, HMG
          Mag=60l; 2000 rnds, Cargo=23.95Kl, ObjSize=Avg,
          EMlevel=Faint
 
Remarks:  This is the Fleet Type sub from the Pacific theater of
WWII.  
 
    Don't you hate it when players drop in on your nice little low
tech planet and proceed to loot, kill and maim and you don't have
anything to throw at them?  Just wait till they try to refuel...
 
    Admittedly, it is going to be outclassed by almost any
starship, but consider, most starships primarily rely on
electromagnetic and other sensors meant to find targets either in
air or in vacuum.  I can't think of many spacecraft that have audio
sensors.  A densitometer might find the sub, but remember the sub
is the same density as the water around it, and besides most
civilian spacecraft don't have densitometers either.  Of course if
your players do have accurate sensors you can always throw a wolf
pack at them...  or a battleship...
Ping...
    Ping...
          Ping...
                      "High Speed Screws approaching!"
HeHeHeHeHeHeHe
 
Scott Kellogg
 
    via   Stephen D Smith   USENET: m0068@tnc.UUCP
                            BIX: sdsmith
- - --Name = STEPHEN SMITH  Mailbox # = 68

-------- TML Message #1920 --------

Archive-Message-Number: 1920
Date: Mon, 3 Dec 90 13:03:58 -0500
From: wrgate.wr.tek.com!tnc!m0068@uunet.uu.net
Subject: Designs from Scott Kellogg 12/3/90

From: m0068@tnc.UUCP (Stephen D Smith)
Organization: personal mailbox at The Next Challenge
 
*********************************************************
I have no access to e-mail so you will not be able to 
reach me very easily and there will be long gaps between
my having access to any comments to any designs or ideas
you might have but I would appreciate it
 
      Scott Kellogg      (703)-836-8352
      1202 S. Washington St. #107
      Alexandria, VA, 22314
*********************************************************
 
Dreadnaught TL 15, "Kokirrak" Class
 
CraftID:  Dreadnaught Type BB, TL 15, MCr 242672.5
Hull:     (180000/450000) Disp=200000 Config=4SL, Armor=76G,
          Unload=5387672, Load=5574778.5
Power:    (32808/43744) 5905422 Mw Fusion, Dur=30 @ low power (no
          offensive wpns except BLasers, Agility=0) Combat power
          consumes 2 days reduced fuel per day)
Loco:     (45900/61200), Manuver=6G, (13500/18000) Jump=4,
          Agility=2 NOE=190, Cruise=750kph, Top=1000kph,
Commo:    Radio=System*30, Maser=System*30, Meson=System,
          RadioJam=System
Sensors:  EMM, P-EMS=Interstel*3, A-EMS=FarOrb*3,
          Densitometer=1km*3, Neutrino=10kw*3, EMS-Jam=FarOrb*3
          ActObjScn=Rout          ActObjPin=Rout
          PasObjScn=Rout          PasObjPin=Rout
          PasEnScn=Simp           PasEnPin=Rout
Off:      HPoints=2000
          Meson Gun=T0x   Missile=x90     ParticleAcc=x70
          Batt        1           33                23
          Bear        1           50                33
          BLasers=x09 FGun=x06
          Batt        33          33
          Bear        50          50
Def:      DefDM=+9 Meson Scn-8, NucDamp-9, Blk Globe-4
          SCaster=x07 Repulsor=x09
          Batt        33          13
          Bear        50          20
Control:  Computer=9fib*3, LrgHoloDisp=20, HoloHUD=1289,
          HoloLink=1289, Electronic Circuit Protect
Accom:    Crew=963 5*200 (Command=132, Bridge=49, Engineer=365,
          Gunner=61, Flight=20, Maintain=297, Medic=7, Steward=32)
          Env=Basic Env, Basic is, Extend is, Inertial Comp, Grav
          Plate, Subcraft=50 ton*10
Other:    Cargo=54029Kl, Magazine=57915Kl, (353b-r) Battery
          round=1650 missiles, Fuel=1321961Kl, Scoops, Fuel
          Pure=72hr, ObjSize=Lrg, EMlevel=Mod
 
Remarks:  "The 'Kokirrak' class dreadnaught is one of the more
common classes of capitol ships in service in the Spinward Marches;
a total of four BatRons of this type serve on permanaent station,
with harbor assignments at Rhylanor, Regina, Jewell, and Mora. 
Generally, one squadron of Kokirraks is dispersed into independant
ships with ancillary escorts.  On patrol, the ships combine
training operations with routine patrols amd reaction operations.
 
    The 'Kokirrak' is a preferred ship for flagship operations due
to its extensive admiral's quarters, which include command and
communications equipment, as well as entertainment chambers.  The
ship is capable of controling a large fleet engagement within a
system, as well as holding its own in battle; the combination of
fleet controller and line-of-battle ship makes it an asset in
nearly any space combat situation.
 
    Troops:  Normally, the 'Kokirrak's do not carry troops.  It is
possible to install modular quarters for up to 2,000 troops
(usually only 1,000 are carried) in the cargo hold.  A squadron of
eight 'Kokirrak's can carry between 8,000 and 16,000 troops or the
equivalent of a reinforced division.
 
    Black Globe Generators:  This class of dreadnaught, when
originally designed and constructed, mounted black globe force
field generators.  Over the years, various ships have suffered
black globe generator failures, and the devices have not been
replaced.  When encountered, there is approximately a 50% chance
that the ship will mount a functioning black globe (factor-4).
 
    The 'Kokirrak's are one of the older classes of dreadnaughts
in Imperial service, and are now being phased out of service. 
Within the last decade, several ships have been disposded of to
other services such as the scouts, and to other governments,
including sector navies and client-states in the Spinward border
regions of the Imperium."   - Supplement 9:  Fighting Ships
 
Original High Guard Design by Tim Brown, Frank Chadwick & Marc
Miller
Reprinted without permission            (No Kill I)
 
Scott Kellogg
 
    via   Stephen D Smith   USENET: m0068@tnc.UUCP
                            BIX: sdsmith
- - --Name = STEPHEN SMITH  Mailbox # = 68

-------- TML Message #1921 --------

Archive-Message-Number: 1921
Date:     Mon, 3 Dec 90 12:59:19 EST
From: "Robert S. Dean" <rsdean@crdec8.apgea.army.mil>
Subject:  Caravans and Starships

Jim Baranski writes:

> Subject: (1898) RE: Shipping

> This is a response to Robert Dean's response to me...

> He suggests that caravans made a better model for star trading then water
> shipping.  He mentioned that sea shipping was quite a bit cheaper then
> caravans, especially in bulk.  I agree with him mostly, but I am wondering why
> expensive cargos were shipping in caravans then ships?  Why wasn't all shipping
> (where possible) done by sea; was there any advantages to shipping by caravans.
> Was it substantially quicker, so that expensive cargos could have a quick
> turnaround?

I looked back over what I said, and there was one important thing that got 
left out of my remark.  I think that a better analogy for interstellar shipping
than 16th century sea trade would be the pre-15th century caravan trade.  
The critical difference is that by the 16th century you had direct sailing 
routes with these exotic far-off places that provided those goods that you 
were willing to spend enormous amounts of money on, like silk and pepper.  
Ultimately, this decreased the price and made them available to larger 
quantities of people, so that, tea drinking for example, was common in 18th 
Century England despite the fact that every pound of tea was carried thousands
of miles by sea.  A caravan had to make many intermediate stops, as do our 
starships, for the equivalent of refueling.  A sailing ship's cruising radius 
was only limited by the amount of food and fresh water it could carry (and 
even water could be obtained), which meant that voyages of many months (and 
even years) were achievable.  This has a strong effect (I think) on the 
economics of the transportation method.  So a caravan, I think, was more like 
our ships--to make a journey lasting months across a desert (space) you had 
to stop frequently (weekly) at towns and oases (planets and star systems) 
along the way.  A sailing ship would be the functional equivalent of a 
starship that needed no jump fuel.

Rob Dean

-------- TML Message #1922 --------

Archive-Message-Number: 1922
Date:     Mon, 3 Dec 90 12:59:44 EST
From: "Robert S. Dean" <rsdean@crdec8.apgea.army.mil>
Subject:  Minimum Armor


John H. Kim Writes:

> Subject: (1902)  Minimum Starship Armor

> Here's a possible reason why the minimum ship armor should
> be 40 instead of 8 as Robert Dean came up with after glancing
> at how LDEF did in five years in orbit.

> In the Traveller universe, space is dirtier.  There are
> a lot of ships moving around.  There is debris from past
> battles.  You didn't think all that sand you threw out
> to protect yourself from lasers just disappeared?  There's
> bound to be lots of paint, metal, sand, and on and on
> floating around just waiting to punch a hole in your hull.

> True, your chances of running into a grain of sand or chunk
> of metal are still remote, but the probability will be higher
> (esp. if you consider a spacecraft lifetime of 50+ years)
> and the average damage from a collision will be greater due
> to larger particle size.  Minimum design standards would
> reflect this.

Well, maybe so.  On the other hand, it might well be more economical to 
accept occasional damage and pay for repair costs.  A possible analogy would 
be modern automobile windshields, which could be made of bullet proof glass.  
We don't because the odds of getting a stone chip big enough to require 
replacing the window are small enough that it isn't worthwhile.  It would 
become even less worthwhile if you could patch your windshield for small 
dings, rather than replace it. As far as this applies to TDR and vehicle rule
redesign, I am more interested in the moment in coming up with reasonable
values than I am in trying to rationalize the odd rules that currently exist.

Rob Dean

-------- TML Message #1923 --------

Archive-Message-Number: 1923
Date: Mon,  3 Dec 90 13:14:35 -0500 (EST)
From: William Dow Rieder <wr0k+@andrew.cmu.edu>
Subject: Re: (1909) Maneuver drives

Leonard Erickson writes:

>No, reaction drives will work just fine. It's just that some people
>hear "reaction drive" and think of our current *chemical* rockets. A
>fusion rocket uses 1/1500 of the fuel. So they *do have reasonable fuel
>requirements, and endurance. I checked the original rules, and a type-S
>scout would *still* be able to run it's manuever drive at full throttle
>for a week if you assume it is a fusion rocket! Or ships should have
>similar endurances.

Wrong.  I don't have the mass for a scout handy, but it was close to
1 ton per kl = ~1350 tons for the whole ship.  2 G's for a week gives
a net velocity change of  ~12,000 km/sec.  Using the speed of light as an
upper bound for the exhaust velocity we get a minimum mass fraction
of 4% just for reaction mass (totally ignoing energy requirements).  This
gives 54 tons mass needed.  The scout had 20 disp tons of LH2 for the
powerplant and manuver drives = 20 tons mass - not enough.  Check
your math before making specific claims.

					W. Dow Rieder

 	When the only tool you have is a hammer, all your problems
start to look like nails...

-------- TML Message #1924 --------

Archive-Message-Number: 1924
Date: Mon,  3 Dec 90 13:25:33 -0500 (EST)
From: William Dow Rieder <wr0k+@andrew.cmu.edu>
Subject: Re: (1902)  Minimum Starship Armor

Here are some serious reasons for starships to have armor 40:
1)  The ship has to be able to cruise through the Van Allen belts of gas
giants without endangering the crew in order to use wilderness refueling.
2)  In-system speeds (at least using the MT manuver drives) can easily
get up to thousands of km/sec, making micrometeorites and other junk
four orders of magnitude more dangerous than when the ship is just
sitting in orbit (KE = 1/2 mv^2).

					W. Dow Rieder

 	When the only tool you have is a hammer, all your problems
start to look like nails...

-------- TML Message #1925 --------

Archive-Message-Number: 1925
Date: Mon, 3 Dec 90 14:05:40 PST
From: Vote For NoneOfTheAbove Write In Candidate 03-Dec-1990 1612 <baranski@meridn.enet.dec.COM>
Subject: trade

Date: Sun, 2 Dec 90 15:04:23 -0700
From: FELLOWS STEVEN B -5 CR <sfellows@slate.mines.colorado.edu>
Subject: (1908) Shipping: Interstellar Trade: Why?
 
"A few reasons why I think people will be dispersed throughout space, receiving
goods from other planets."
 
"1)Overpopulation.   'creates a market for food'

The only cure for overpopulation is population control.  Emigration may have
some effect on it, and feeding it only makes it worse.  I really have a hard
time believing that it's economical to feed a planet from another planet as a
matter of course.  You need a *good* reason to have a sizable population on a
planet that can't support it.  It makes much more sense to put the people where
the food is.

I agree with you that Traveller seems to assume that space shipping costs are
negligible, but on the other hand, player traders can make out quite well. This
doesn't match up.  Run some scenarios past yourself.  Say you have a planet
full of people in one system, and a farming planet in another system.  Assume a
reasonable price for the food, and add in the trading cost, and see what you
get.

"2)The necessary support industry is not available and would be too costly
to transplant."

This does happen out of necessity in small colonies or research stations.
But, given the shipping costs in the players guides, I can't see it being
economical to import bulk goods.  small amount of goods will always be traded,
as not much is needed, and it's cheaper to trade for that, but the more that
you need something, the more important it is to produce it locally.

"Land caravans were used instead of sea transport because of the danger and
thus relatively costly expense of sea transport."

Whhhhat?  Caravans are more expensive then sea transport, that's why bulk goods
are sent by sea.

"Additionally, once you get a space faring population why would there be
interest in transplanting a whole society and making it self sufficient? This
would be extremely costly and unattractive to everone but the extremely wealthy
(individuals and organizations)."

I don't know of anyone or any group that wouldn't rather be self sufficient if
it's economically possible.  Again, you seem to assume that transport is
cheaper then development, which I would argue against. 

Jim Baranski

-------- TML Message #1926 --------

Archive-Message-Number: 1926
Date: Mon, 3 Dec 90 19:13:28 -0900
From: George William Herbert <gwh@ocf.berkeley.edu>
Subject: Re: (1899) Minimum Structural Strength


Rob Dean discusses comparing structural strength of modern and Traveller
spacefaring vehicles... I'd like to make a few comments.

Current vehicles are very, very fragile.  As are current airplanes.  Given the
amount of use (and type of use) they are subjected to, a better comparason 
would be with a naval ship than with a Space Shuttle.  A naval ship run 
aground in port simply waits for better tide to get off; were a space shuttle
to land off-field, it would be a $2 billion sculpture.  I can't imagine
that Traveller ships, indended for in excess of twenty years of nearly c
continuous use, would be built anything but very, very strongly.

Also, problems such as atmospheric re-entry heating have to be taken into 
account... without extensive cooling or insulation, all sorts of problems
occur with thin-skinned vehicles.

Besides, if anyone bothers to figure out gas giant skimming loads and such,
i suspect they're going to be um Huge.  [Believe me; one real-world project
I'm working on is a spacecraft that aerobrakes at Jupiter... 8-) ]

- - -george william herbert
gwh@ocf.berkeley.edu

-------- TML Message #1927 --------

Archive-Message-Number: 1927
From: "Mark F. Cook" <markc@hpcvss.cv.hp.COM>
Subject: Pigs,...er...Windshields in Space!!
Date: Mon, 3 Dec 90 22:44:53 PST

In subject (1922) Rob Dean <rsdean@crdec8.apgea.army.mil> writes:

> Well, maybe so.  On the other hand, it might well be more economical to 
> accept occasional damage and pay for repair costs.  A possible analogy would 
> be modern automobile windshields, which could be made of bullet proof glass.  
> We don't because the odds of getting a stone chip big enough to require 
> replacing the window are small enough that it isn't worthwhile.  It would 
> become even less worthwhile if you could patch your windshield for small 
> dings, rather than replace it. As far as this applies to TDR and vehicle rule
> redesign, I am more interested in the moment in coming up with reasonable
> values than I am in trying to rationalize the odd rules that currently exist.

On the other hand, everybody MIGHT have bulletproof glass in their windows
if they ran the risk of breaking one and SUFFOCATING before they got to
the next body shop. :-)

Sorry, Rob.  I couldn't resist.

Later,

        - Mark F. Cook (TDR Archivist)

-------- TML Message #1928 --------

Archive-Message-Number: 1928
From: "Brent L. Woods" <woodsb@zoo.ecn.purdue.edu>
Subject: Re: (1913) Re:  Interstellar Trade
Date: Tue, 4 Dec 90 5:40:44 EST


 In message 1913, adrian@cs.heriot-watt.ac.uk (Adrian Hurt) writes:
 >
 >One thing I haven't seen in Traveller is any equivalent to the old
 >clippers.  Their function was to get tea from China to Britain as fast
 >as possible, to get the best prices.

     Probably due to differing circumstances.  Back in the last century,
there were good economic reasons for having some ships travel from A to
B as quickly as possible while others were able to take more time
reaching their destinations (presumably, things are still that way--I
don't know, since what I know about ocean travel is primarily military).

     In deep space, however...  In one of Larry Niven's Known Space
stories (I *think* it's "Borderland of Sol"--one with Beowulf Shaeffer,
anyway), the protagonist makes the comment that hyperdrive has only
one speed, and *there is never any reason to dawdle in space*.  Human
beings can adapt to a wider range of environments than most people
would think, but vacuum is notoriously low in vitamin content.  ;-)

     The same factors obtain in the Traveller universe.  There are
different distances that individual jump drives can traverse, but as
far as the ship is concerned, they all move at the same speed:  one
jump per week (assuming quick refueling and a need to get somewhere
in a hurry).  Half that if the ship in question wants to spend some
time in port for trading, laying in supplies, performing simple
repairs, and whatnot.

     There *could* be the equivalent of clipper ships, but that form of
travel would be so ruinously expensive (since the ship won't be making
any money along the way) that the cargo had better be *extremely*
valuable (possibly more valuable than I can imagine, and, like Han Solo,
I can imagine a *lot*.  :-) ).

     Actually, now that I think about it a little bit, there *is* (well,
at least *was*) something like a clipper route in the Imperium.  The
IISS operates an _Azhanti_High_Lightning_ class cruiser to do nothing
but carry wine from Earth to Capital for the Emperor's table (I'm told
that tokay is very good, but *really*...).  Note that it takes a *large*
agency of a major government to be able to afford this.

     Now the question becomes "Is there a commodity valuable enough to
justify special multi-jump dedicated shipping?"


- - --
     Brent

INTERNET:  woodsb@gn.ecn.purdue.edu
USNAIL:  2818 S. Sunrise Dr.  /  New Palestine, IN  46163
PHONE:  +1 (317) 861-4844 (voice)


-------- TML Message #1929 --------

Archive-Message-Number: 1929
Date:     Tue, 4 Dec 90 9:10:22 EST
From: "Robert S. Dean" <rsdean@crdec8.apgea.army.mil>
Subject:  Nuclear Fuel Consumption, Part II

Having splattered the list with my first thoughts on the subject yesterday,
I feel impelled to mention at least one semi-major source of error.  The
nuclear fuel should probably be calculated on the density/weight of
uranium oxide, rahter than metallic uranium.  Even if using metallic uranium,
the Ref's Manual's 25tonnes/kl is absurd, as that is the same as a specific
gravity of 25, or a density of 25g/cc.  Even pure uranium only has a density of 
19, and (without looking it up) I think the oxide must be lower.  I dislike it
when the book makes a mistake like that, on an easy to verify number.  Which 
reminds me, most hydrocarebon fuels should weigh about 0.8tons/kl, rather than
1t/kl.

Rob Dean


-------- TML Message #1930 --------

Archive-Message-Number: 1930
Date:     Tue, 4 Dec 90 9:22:17 EST
From: "Robert S. Dean" <rsdean@crdec8.apgea.army.mil>
Subject:  Acceleration Calculation

T.L. Hayes writes:

> About the TDR ship design rules by Rob Dean:
> 
> >       For space faring craft, normal acceleration now becomes
> >       thrust/weight.  If this value is less than one, the craft cannot
> >       lift off from a standard gravity planet. For operations near a
> >       planetary surface, figure speed of spacecraft based on
> >       (thrust/weight)-1 to account for power required to maintain lift.
> >       Agility is equal to the acceleration available after all other
> >       systems have been powered.
> 
> What about Cargo?  Do you mean to imply that some average weight should
> be assumed for acceleration calculations or should you recalculate with
> each cargo run or ignore cargo?  Otherwise (after a brief once over) it
> looks good to me!  I am glad to see that you didn't start over from
> scratch but rather fixed the existing system.  I don't want to learn an
> entirely new game, I just want some of the holes filled!

You have your choice.  What the game currently does with small vehicle .
performance is to calculate it based on the cargo space being completely filled
with water.  This would give you some sort of approximation.  Personally, I'd
do that, plus calculate an empty accelration in case you need to take off in
a hurry sometime.  I realize that the trade people (are you listening?) will
have to come up with cargo densities if you want to recalculate on the basis 
of each cargo.  You may want to do it...it wouldn't take long, especially
if you have a full load of one commodity.

Rob Dean

(Sorry about the spelling.  This keyboard is way too sensitive, and there is no 
way to adjest it for a heavier touch.)


-------- TML Message #1931 --------

Archive-Message-Number: 1931
From: plb@violin.att.COM
Subject: Re: (1913) Re: Interstellar Trade
Date: Tue, 4 Dec 90 9:34:46 EST

Operating System: HP-UX A.B7.00 U
Organization: AT&T-BL, Red Hill System Administration Group (HRSAG)
Location: HR 2C119
Phone: (201) 615-4419
Return-receipt:
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*| 
*| One thing I haven't seen in Traveller is any equivalent to the old clippers.
*| Their function was to get tea from China to Britain as fast as possible, to
*| get the best prices.
*| 

One of the campaigns I ran several years ago was tailor made for
someone who wanted to run characters that were the equivilant of
the owners of the China Clippers.  I had (thanks to one of my
players) a ship design that became very popular within my campaigns
that was a rough analogy to it.  Unfortunately the breifcase that
the design (and its copies) was in turned up missing one fine day
and I lost a lot of good designs as a result.


- - -- 
""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
" Peter L. Berghold  " INTERNET: plb@violin.att.com "+1(908)615-4419   "
" System Adminstrator" BIX     : peteb              """"""""""""""""""""
" AT&T, HRSAG        " DELPHI  : berghold """"""""""""""""""""""""""""""
""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""

-------- TML Message #1932 --------

Archive-Message-Number: 1932
Date: Tue, 4 Dec 90 12:40:49 -0500
From: "T. L. Hayes" <al646@cleveland.freenet.edu>
Subject: Re: Rob Dean's Posts




From: "Robert S. Dean" <rsdean@crdec8.apgea.army.mil>

>How many people use the advance character generation rules now?  I though the
>updated "quick" rules provided a sufficiency of skills to keep the characters
>competitive, and more or less feel that all the extra die rolling in the
>advanced systems is a waste of time.  Just an opinion...

I agree.  I only use the basic character generator and selected parts from
the advanced sections (such as college and military academys).  I had always
planned to expand slightly the pre-service skills section for the basic
system in a way similar to the college expansion posted a few messages ago.

>As two sample calculations, I considered a cylindrical pressure vessel capable
>of containing one standard atmosphere of pressure (14.7psi)  <Sorry about the
>English units--I'm an engineer>.  I considered it to be made of mild steel,
>with no special alloys, etc, giving a yield strnght of approximately 50,000psi.
>I also ignored end cap effects.  I decided that a safety factor of 2.5 was 
>sufficient, so I put in a value of 20,000psi as the maximum allowable stress
>in the skin. At those conditions, a cylinder 10ft in diameter would need a wall
>thickness of less than 0.05 inches, which is less than Traveller armor value
>1.  A 100ft diameter cylinder (ship sized) would require a wall thickness
>of 0.44 inches, about Traveller armor value, between Traveller armor values 3
>and 4.  50,000psi mild steel would be the equivalent of armor type A (soft
>steel).

I have not designed many ships but I don't see how you go from thickness to 
armor value (or vice versa).  Again, I have not designed but maybe half a
dozen ships but if I understand things correctly a 100 ton ship occupies a
volume of 1350 cubic meters and has a mass of 40 tons.  Multiply by 33 for an 
armor factor of 40 and by 1.25 for soft steel and you get 1650 tons for weight 
(mass).  I believe a minimum surface polygon enclosing the volume listed would 
be a sphere 685.6172 cm in radius.  I don't know the density of steel but the 
specific gravity of iron is about 8 gm/cc (which means the density of steel 
is about the same?).  If you assume a mass of 1,650,000 gms and calculate the
thickness of the skin of the sphere you find it to be 0.0349 cm or about 
0.0137 in.  If the density is greater than 8 gm/cc then the thickness will be
even less.  Somebody check these numbers, you know how bad I am with numbers!
Assuming no miscalculations, wouldn't this coupled with your calculations 
mean that the hulls should have a higher armor rating?

>P.S.  There are a number of potentially useful technologies that Traveller's
>reliance on grav manipulation overshadows.  Laser launch systems and 
>beanstalks are two that spring immediately to mind.

True but these limit ships to civilized, high tech planets.  Anti-grav 
allows the ship to come and go when and where it wants (which is good for
smugglers and the like).

TLH


- - --
T.L.Hayes                  |
MIT/Lincoln Laboratory     |
Lexington, MA              |

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