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Subject: TRAVELLER digest 390
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			    TRAVELLER Digest 390

Topics covered in this issue include:

  1) Mertactor debate...
	by Christopher_Griffen@dmcwave.com (Christopher Griffen)
  2) Plasma Trails, Missiles, and Relativity
	by jlockett@hanszen.rice.edu (Joseph L Lockett)
  3) Question
	by That Computer Guy <darkstar@chopin.udel.edu>
  4) Re:Relativity and its effects on navigation.
	by "Bruce Johnson" <JOHNSON@tonic.pharm.arizona.edu>
  5) Re: TRAVELLER digest 388
	by "Sinbad Sam" <sinbad@metronet.com>
  6) Hoverboards
	by cmdrx@magicnet.net (Commander X)
  7) 1997 possible impact?
	by Bill Currie <BILLC@teleng1.tait.co.nz>
  8) Re: Plasma Trails, Missiles, and Relativity
	by merrick@Rt66.com (Merrick Burkhardt)
  9) Navigation [science]
	by Duncan Law-Green <dlg@jb.man.ac.uk>
 10) RE: Relativity and its effects on navigation.
	by Neil Taylor <neil@owl.uk.gdscorp.com>
 11) RE: Grav Boards
	by Neil Taylor <neil@owl.uk.gdscorp.com>
 12) Re: Pulse Rifle
	by Liam_McCauley@qsp.co.uk
 13) RE: Relativity and its effects on navigation
	by David Elrick <Dave.Elrick@ps.co.uk>
 14) RE: The ongoing Mertactor Debate
	by David Elrick <Dave.Elrick@ps.co.uk>
 15) RE: Admiralty Manual of Seamanship
	by David Elrick <Dave.Elrick@ps.co.uk>

----------------------------------------------------------------------

Date: Thu, 24 Aug 1995 11:46:21 -0700
From: Christopher_Griffen@dmcwave.com (Christopher Griffen)
To: traveller@MPGN.COM
Subject: Mertactor debate...
Message-ID: <03cc9040@MailXFER.DMCWAVE.COM>

     Hans Rancke-Madsen writes:
     
     >>As it is, we _know_ that Mertactor was settled already by
     the year 300, while others (the whole spinward half of District 268)
     wasn't.<<
     
     In Supplement 8, Library Data, I have the information to which I think 
     you're referring.  But can you tell me where it states exactly that 
     _Mertactor_ was settled in about 300, and not just that interstellar 
     region?  If you can, I would gladly concede.
     
     >>>You're forgetting one thing that may negate most of this part of 
     the 
     >debate:  fuel scoops.
     
     No, you missed the salient part of my argument. How can someone be 
     said to
     come from Mora when they don't come from Mora?<<
     
     I don't quite know what you mean here.  But I would like to know your 
     views on my fuel scoops argument.  Fuel scoops eliminate the lion's 
     share of the costs of interstellar travel.
     
     >>If you choose to believe that any politician would consider that a
     reasonable price then we just have to disagree on that point.<<
     
     Okay.
     
     >>Have you actually thought a little about the figures involved?<<
     
     Yes, I have.  But if you think whipping up a few figures on a 
     calculator gives you an accurate estimation of the cost, I think we're 
     coming from rather different angles.  My observations about human 
     motives are that as a race, we can be extremely irrational and do 
     things for reasons that our descendents will question as ludicrous.  
     In short, anything is possible.  Cost doesn't factor into it.
     
     Pick up a book on any region's history and you'll find descriptions of 
     enterprises that were foolishly conceived and poorly planned.  My 
     world view is that we often do stupid or even crazy things, but 
     somehow, things work out and people muddle through.  That's the way I 
     envision the Mertactor situation.
     
     >>I still think that you can stuff the soils with chemicals and the 
     air with
     CO2 as much as you like but without water it's still going to be a 
     desert.
     However, I don't know enough about the subject to be dogmatic about 
     it.
     <<
     
     Me either.  Let's leave it to the chemists.  Seriously though, anyone 
     who opts to use my Mertactor description can translate my statement 
     about the verdant landscape of the planet as "only on the oceanic 
     coasts" or "only in Mertactor's large river valleys" or however they 
     want to.  I envisioned the standard atmosphere, the presence of 20 
     percent water and the fact that my World Builder's Handbook die roll 
     indicated that the planet had native life, to mean that the landscape 
     was verdant.  To what degree, I'll leave to the individual Trav 
     player.
     
     >>Hmmm... perhaps we've been arguing at cross-purposes. I thought that 
     these
     RICE papers were supposed to describe things as they might be in the 
     GDW
     universe. If you say that it just describes the way things are in YOUR
     Traveller universe then a lot of my arguments are futile. I may still
     think that you social dynamics are flawed, but then, you're perfectly
     entitled to make your Traveller universe anything you like.<<
     
     Actually, I thought everything put up on the TML was subject to 
     criticism.  I fully appreciate your input on this.  I even changed 
     some things because of our discussion.  I didn't take _everything_ 
     you've said as gospel, but you may have noticed the Mertactor Version 
     1.1 I put out.
     
     How about this:  1) I deport the colonists from Fornice or Glisten 
     instead of Mora, and 2) I change the date to 305 or thereabouts?  Let 
     me know what you think.
     
     At any rate, Hans, like I said, your input is great.  Please use your 
     search command to find my papers on Rhylanor and Jae Tellona and give 
     me your two cents on those.  I can't promise I'll like what you say, 
     but I sincerely want to put out the best papers possible and would 
     appreciate your advice.
     
     I have quite a bit of the documentation on Traveller history, but not 
     all of it.  Generally I use the two Library Data Supplements, the 
     MegaTraveller Imperial Encyclopaedia, Survival Margin, what JTAS, 
     MegaTraveller Journal and Challenge issues I have and the DGP aliens 
     modules.  I've noticed that there's a lot more background material in 
     such books as The Spinward Marches Campaign (which I can't find a copy 
     of) and the Traveller Book (hardcover - short library entries at back 
     of book).
     
     --Chris

------------------------------

Date: Thu, 24 Aug 1995 13:50:58 -0500 (CDT)
From: jlockett@hanszen.rice.edu (Joseph L Lockett)
To: traveller@MPGN.COM
Subject: Plasma Trails, Missiles, and Relativity
Message-ID: <199508241851.NAA04890@harry-clay.hanszen.rice.edu>

Re: the ongoing discussion on detecting HEPlaR plasma trails, I'd recall
Wien's Displacement Law, which states that the peak wavelength of emitted
photons is given by:

	Lambda(max) * T = 0.29 cm*K

Given the high temperature of the emitted reaction mass (which I don't
have handy), I suspect you'd get quite short-wavelength radiation, very
possibly even in the X-ray range, which should be FAR easier to detect
than mere thermal (infrared) emissions, and also less characteristic of
"harmless" natural phenomena.  I know *I'd* perk up if a raging X-ray
source streaked into the solar system!

I suspect this, along with thermal radiation from those huge fusion
plants, is exactly what is used in the "lock-on" from Brilliant Lances
et alia.  This doesn't help for contact missiles (which it sounds like
some people are re-proposing), since Traveller lasers are such awesome
point-defense weapons in interplanetary space.  (Would that we had a
harder-sf universe without gravitic focussing, but then it wouldn't be
Traveller any more... :-)  Detonation-laser missiles, of course, would
use the same targetting and tracking information as larger vessels do:
they can just afford to get closer to deliver their punch.

> From: tcgny!uunet.uu.net!tcgny!berghold@uunet.uu.net (Peter L. Berghold)
> Subject: Relativity and its effects on navigation.
> 
> Given that everything in the universe is moving (quickly!) how do you
> calculate where things are in space?  The light you see from a distant star
> system may or may not really give you a clue as to its location.  In the
> time it takes for light or other radiation from a star system to get to you
> the object has moved from the point it was when the light was emitted.  Same
> for your perspective in space.  The place you are observing from is *also*
> moving so that changes the "value" for the observation even more...
> 
> So what is a navigator to do?  This makes navigating in space REAL
> interesting...

<shrug>  You're both moving around the galactic center, so you use that
for reference, subtract out its motion through space, then just adjust for
individual variances.  Since stars are unlikely to arbitrarily change their
direction of motion, you make sure you have an adequate base of observations
of proper motion, red/blue shift of spectral lines, etc. so that you can 
predict the destination star's movements.  Yes, it might get tricky if we
were going from here to the Larger Magellanic Cloud, or between different
spiral arms all in one hop, but for distances of one to six parsecs, I doubt
it makes that much of a difference.  Perhaps you just have to make a little
extra boost at the end of the trip to "catch up" on the star's (or planet's)
orbital motion.

----------------------------*-------------------------*-----------------------
Joseph L. "Chepe" Lockett   | "Nullum magnum ingenium | GURPS fan, Amiga user,
jlockett@hanszen.rice.edu   |  sine mixtura dementiae | Shakespearean scholar,
http://www.io.com/~jlockett |  fuit." -- Seneca       | actor and director.
----------------------------*-------------------------*-----------------------

------------------------------

Date: Thu, 24 Aug 1995 16:06:17 -0400
From: That Computer Guy <darkstar@chopin.udel.edu>
To: traveller@MPGN.COM
Subject: Question
Message-ID: <199508242006.QAA29493@chopin.udel.edu>


I don't suppose that anyone out there could possibly tell me what the
displacement of the Trasea Grav Bike from WBH was?  It's at home, which
is not where I'll be for the next few days.  8(

Thanks in advance...

        --Jerry

8) Jerry Alexandratos                %  "Nothing inhabits my    (8 
8) darkstar@strauss.udel.edu         %   thoughts, and oblivion (8
8) darkstar@canary.pearson.udel.edu  %   drives my desires."    (8

------------------------------

Date:          Thu, 24 Aug 1995 13:46:59 MST7
From: "Bruce Johnson" <JOHNSON@tonic.pharm.arizona.edu>
To: traveller@MPGN.COM
Subject: Re:Relativity and its effects on navigation.
Message-ID: <6294A7E039E@tonic.pharm.Arizona.EDU>

Peter says:

>I know some folks are going to groan when they read this and say "Oh no..
>not this again" but I've gotta get this outta my system.
>
>Just read Steven Hawkin's book "A Breif History of Time" and some of the
>points raised in the book make for some interesting problems for Traveller
>and space faring society at large.
>
>Given that everything in the universe is moving (quickly!) how do you
>calculate where things are in space?  The light you see from a distant star
>system may or may not really give you a clue as to its location.  In the
>time it takes for light or other radiation from a star system to get to you
>the object has moved from the point it was when the light was emitted.  Same
>for your perspective in space.  The place you are observing from is *also*
>moving so that changes the "value" for the observation even more...
>
>So what is a navigator to do?  This makes navigating in space REAL
>interesting...

	The same way we navigate stuff here in our own solar
system...triangulate from known locations, or at least known 
vectors. We use specific, bright, distant stars...I'll be that
Traveller navigators use specific, bright, distant galaxies, or
quasars.  Everything IS moving in the universe, but almost
everything is moving in a simple path. Yes, the light you see isn't
really where the object is, but you know it's vector in relation to
your anchor objects, and the rest, as they say, is trivial. Note,
this is the mathematic trivial, where you may need TL 17 massively
parallel computer systems to perform those `trivial' calculations. 
All it takes, in a relativistic universe, is to designate some known
point as `zero point', calculate all your vectors on that, and
navigating is easy. The trick is to pick distant enough reference
points so that drift in your system from the movement of those
`anchors' are insignificant to your calculations. This reduces
navigation from a relativistic to newtonian physics. Yes, your
astrogation tables may move out of synch by miles per year, but
exact location doesn't matter, all you need is to do is get close
enough for Imperial work.

	This does raise the fact that survey ships will have some pretty
robust astrogational computer systems and programs.  Most other
ships would use lookup tables.  
Bruce Johnson
Information Technology/College of Pharmacy
The University of Arizona
johnson@tonic.pharm.arizona.edu 


As if this place HAD any opinions...

------------------------------

Date:          Thu, 24 Aug 1995 16:35:52 +0000
From: "Sinbad Sam" <sinbad@metronet.com>
To: traveller@MPGN.COM
Subject: Re: TRAVELLER digest 388
Message-ID: <199508242126.AA04749@metronet.com>

 
> Date: Thu, 24 Aug 1995 06:14:57 GMT
> From: "Brendan O'Donovan" <Brendan@odonovan.demon.co.uk>
> To: traveller@MPGN.COM
> Subject: HEPlaR drive plumes
> Message-ID: <68@odonovan.demon.co.uk>
> 
> Assume all that the energy from the drive went into heating the reaction mass. 
> For the free trader this gives the mass 100MJ of energy each second. These MJ 
> are distributed through the volume of exhaust produced in this time. This gives 
> an energy density of about 300J/m^3 (at 4hex/turn, 1G). If you want a drive 
> plume 10,000 km long, then the energy of the exhaust will be given up in 150 
> seconds. Very roughly, if we pretend that energy is lost at a uniform rate, this 
> gives an output of 2W/m^3. This can be visualised as a 100W lightbulb every 10m 
> along the exhaust trail. This seems really dim for the ranges involved, but I 
> don't know how easy this would be to detect using sensors. Perhaps someone who 
> has more knowledge of real world sensor operations could finish this off. 
> 
> Also, in my apologising post I made another mistake - 'heterolytic' should be 
> 'homolytic'.
> -- 
> Brendan 
> 

As former USN Firecontrol Tech, the system that I used had a low 
light camera that could track a aircraft at night, if the aircraft 
had a single cockpit intrument light on, at 20nm under optimal 
conditions. the technology of this camera used a vidicon tube, circa 
1970's technology. At various times on cruises we tracked satelites 
going overhead at night under various conditions. Extrapolating to todays's 
technology it easy to track a 100w bulb to over 100nm. At TNE tech 
levels it would be easy to detect such a trail at over 5 light secs 
provided the background did not mask out the trail.

Sinbad Sam
sinbad@metronet.com

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------------------------------

Date: Thu, 24 Aug 1995 18:39:00 -0400
From: cmdrx@magicnet.net (Commander X)
To: traveller@MPGN.COM
Subject: Hoverboards
Message-ID: <199508242242.SAA27245@magicnet.magicnet.net>

>From the RQS Fortune and Glory
Commander X Transmitting
*>BEGIN TRANSMISSION<*

I would like to thank everyone who pointed out the error in mass on the
Hoverboard. Checking that little conversion chart in the front of FF&S, yes
1 tonne is 1000kg and not 2000kg as i have calculated.  But still, 43kg is
relatively heavy to cary arround (it's 43kgx2.2=94.6lbs! I am sure that 2.2
is the conversion ;)  ).  This was done before I had the RC Equipment
Rulebook and the Grav-belt upgrade rules, I am currently working on using
this to upgrade the Hoverboard, call it Hoverboard version 2.0! :) I hope I
do get a skatebard this time (maybe if the the TL was 15....)

As Andrew Boulton pointed out, yes there is room on the thing for boosters,
thrusters, computer controlled terain following avionics, etc...

Have fun with the idea and again thanks for the errata!

***COMMING SOON TO THE TML****

COMMANDER X TALES FROM THE LINE 2
TOPIC: HACKERS, CYBERDECKERS, COMPUTER EMPATICS, AND YOU
WATCH THIS SPACE!!!!!

And now for something completely different, the signature....


>From the RQS Fortune and Glory.
KEEP THE FLAME!!!
Commander X out....<click>
**>END TRANSMISSION<**


------------------------------

Date: Fri, 25 Aug 1995 11:24:42 +1100
From: Bill Currie <BILLC@teleng1.tait.co.nz>
To: traveller@MPGN.COM, xboat@MPGN.COM
Subject: 1997 possible impact?
Message-ID: <441B3761BD@teleng1.tait.co.nz>

Not realy on topic, but...

I heard that there may be a comet/meteor/asteroid heading our way for 
a rendevous in '97.  Could some kind soul please point me in the 
right direction for more information.
+--------------+-----------------------------------+
|Bill Currie   | "Watch that first step..."        |
|Christchurch  | Jump trooper motto.               |
|New Zealand   |                                   |
+--------------+-----------------------------------+

------------------------------

Date: Thu, 24 Aug 1995 17:33:26 -0600 (MDT)
From: merrick@Rt66.com (Merrick Burkhardt)
To: traveller@MPGN.COM
Subject: Re: Plasma Trails, Missiles, and Relativity
Message-ID: <9508242333.AA17713@Rt66.com>

Howdy,

> 
> I suspect this, along with thermal radiation from those huge fusion
> plants, is exactly what is used in the "lock-on" from Brilliant Lances
> et alia.  This doesn't help for contact missiles (which it sounds like
> some people are re-proposing), since Traveller lasers are such awesome
> point-defense weapons in interplanetary space. 

Huh?  This would *help* KE missiles.  They can use passive homing, and since
they're small, you might not ever know you're locked on.  Remember that 
missiles (for the most part) don't use fusion drives of any sort, they're
chemical rockets.  And lasers aren't very good since using the sensor rules 
you'd never even see them :) (in BL, anyway)

Actually, when I did my various sensor rules, I made off-axis line of sights
give a small diffmod, but maybe it should be higher.  What about EMM?

I need to think about the exhaust more... hmmm (fun, fun :)

-Merrick

------------------------------

Date: Fri, 25 Aug 1995 00:44:12 +0100 (BST)
From: Duncan Law-Green <dlg@jb.man.ac.uk>
To: TML <traveller@MPGN.COM>
Subject: Navigation [science]
Message-ID: <Pine.SOL.3.91.950825004100.2911B-100000@fafnir>


>Given that everything in the universe is moving (quickly!) how do you
>calculate where things are in space?  The light you see from a distant star
>system may or may not really give you a clue as to its location.  In the
>time it takes for light or other radiation from a star system to get to you
>the object has moved from the point it was when the light was emitted.  Same
>for your perspective in space.  The place you are observing from is *also*
>moving so that changes the "value" for the observation even more...

OK...assume that your ship's just emerged from Jump....

To establish a sky "reference grid" (i.e. which way is celestial
north) make all-sky passive EMS scan looking for quasars --- bright
optical (and often radio) sources associated with massive active
galaxies at extreme distances (gigaparsecs). Since quasars are so far
away, they won't be affected by parallax, and the quasar "sky" will
look the same wherever you are in the galaxy. Now the navigator knows
which way is up...

To establish _where_ you are, assuming no artificial aids (nav beacons
etc.): This is trickier, because the point of origin, the destination
system and all the stars around are moving on different orbits about the
galaxy's centre of gravity, taking about 225 million years to do one
orbit. Typical differences in velocity between one star and another
are 10's to 100's of km per sec. Stars _do_ move around, and 1st
Imperium-era charts could be _seriously_ wrong by 1200 (systems in the
wrong hex!).

Natural beacons include bright O-type stars, which are both
rare, and readily visible from long distances ("oh, that must be
Deneb!"), and pulsars (rapidly-rotating neutron stars) which have the
added advantage of being pretty accurate clocks with well-defined slow-down
rates. Observe half a dozen or so pulsars --- their positions on the sky
will tell you where you are, and their current "pulse rates" will tell
you _when_ you are and how fast you're moving.

Oh, I forgot to mention...the pulsars are moving as well, faster than
the stars are (>300 km/sec). Better make sure that your charts are up
to date :-)

A colleague of mine is here at Jodrell Bank is conducting a
pulsar parallax survey...her work could form the basis of the first
starship charts! 

Duncan Law-Green
=-=-=-=-=-=-=-=-

dlg@jb.man.ac.uk  ------------------------------- NRAL Jodrell Bank
dlg@ryouko.demon.co.uk ----------------------------- No Fixed Abode



------------------------------

Date: Fri, 25 Aug 1995 08:21:56 EDT
From: Neil Taylor <neil@owl.uk.gdscorp.com>
To: traveller@MPGN.COM
Subject: RE: Relativity and its effects on navigation.
Message-ID: <0099564C.4E4CF560.36@arc.uk.gdscorp.com>

tcgny!uunet.uu.net!tcgny!berghold@uunet.uu.net (Peter L. Berghold) writes:

>Given that everything in the universe is moving (quickly!) how do you
>calculate where things are in space?  

given the subject header, it seems you misunderstand the speeds involved:  for 
relativity to have significant effects, you have to be travelling a significant 
fraction of the speed of light! Anything less than  0.01c can be ignored for 
most purposes.
 
>The light you see from a distant star
>system may or may not really give you a clue as to its location.  In the
>time it takes for light or other radiation from a star system to get to you
>the object has moved from the point it was when the light was emitted.

not really - the stars motions have been tracked and catalogued for a long time 
(referred to as their "proper motion" rather than their apparent motion as the 
observer moves)
These proper motions are modest (5-50km/s) and subject to all the normal laws of 
gravity and motion - and can be predicted with good accuracy for long periods.  
Most of the time stars are so far from each other that they can be treated as 
moving through a uniform gravitational field due to the galaxy as a whole, with 
gradual variations on lang time scales (10,000's of years).

>  Same
>for your perspective in space.  The place you are observing from is *also*
>moving so that changes the "value" for the observation even more...

you just pick a reasonable large frame of reference, such as the galaxy as a 
whole, or better, the frame defined by the average of all the nearby galaxies, 
and measure yourself and the other stars relative to that.  The fact that your 
overall from may be drfiting doesn't actually matter.  [For the curios, it 
doesn't matter if your frame is moving *uniformly*, and if it is accellerating, 
you can tell - accelleration is absolute.]

General Relativity provides the maths to use in all cases, including those where 
you haven't a clue as to who is moving... 

>So what is a navigator to do?  This makes navigating in space REAL
>interesting...

use the standard Nav. programs bought from MegaHard(tm) your local galactic SC 
(Ship's Computer) supplier... They have relativistic corrections already built 
in.. You can even jump at near-light-speed (if you can get up to it) and come 
out with the same vector -- its your own problem to slow down again...
--------------------------------------------------+
-- Neil Taylor              neil@uk.gdscorp.com --|
-- Graphic Data Systems Ltd,                    --| 
-- Wellington House, East Rd, Cambridge CB1 1BH --|
--------------------------------------------------+

------------------------------

Date: Fri, 25 Aug 1995 08:23:23 EDT
From: Neil Taylor <neil@owl.uk.gdscorp.com>
To: traveller@MPGN.COM
Subject: RE: Grav Boards
Message-ID: <0099564C.81B29CC0.38@arc.uk.gdscorp.com>

ok - who rememebrs the final scene in "Dark Star" where the guy surfs down into 
the planet's atmosphere riding a piece of space-junk?
--------------------------------------------------+
-- Neil Taylor              neil@uk.gdscorp.com --|
-- Graphic Data Systems Ltd,                    --| 
-- Wellington House, East Rd, Cambridge CB1 1BH --|
--------------------------------------------------+

------------------------------

Date: 	Fri, 25 Aug 1995 09:47:35 +0100
From: Liam_McCauley@qsp.co.uk
To: traveller@MPGN.COM
Subject: Re: Pulse Rifle
Message-ID: <03d8ec90@pc173.qsp.co.uk>

     Thanks for all the help with materials & caseless ammo for my Pulse 
     Rifle design.  Thanks also for any compliments.  I'm especially glad 
     to hear that it might get used in someone else's campaign.
     
     I've re-done the design using Lahtinen's caseless ammo notes, and will 
     put the summary at the end of this post.
     
     The low short range for the weapon is due to the very short barrel 
     length (24.7cm c.f. average barrel length of 49cm for the ammo), and 
     because the ammo is HEAP (0.75 multiplier).  I imagine that this would 
     give it a hell of a muzzle flash.
     
     The cannister round for the grenade launcher that someone asked about 
     simply holds buckshot.  Being lazy, I couldn't be bothered going 
     through the full sequence for the ammo again, so I just left it as an 
     exercise for the reader ;-).
     
     I noticed that the only thing that would change if I dropped the TL 
     from 12 to 10 would be the explosive energy of the HEAP round.  This 
     gives a damage of 5, rather than 6.  Are there no other developments 
     in standard slug weapon design above TL 10?
     
     There are a few things I would change if I was designing the weapon 
     myself from scratch (longer barrel, shorter cartridge to improve range 
     and recoil), but I wanted to stay close to the parameters I had been 
     given.  These were (from "Aliens: Colonial Marines Training Manual"):
     
     Rifle without Mag 3.4Kg
     Full Mag          1.5Kg
     Barrel Length     24.7cm
     Rifle Length      69.5/84cm
     Muzzle Velocity   840m/s
     Max Range         2.1km
     Max eff. Range    500m
     Cyclic Rate       900rpm
     
     "The M41 fires the standard US M309 10mm * 24 round.  This ammunition 
     comprises a 210 grain (13.6g) projectile embedded within a rectangular 
     caseless propellant block of Nitramine 50.  The propellant content is 
     small, but highly efficient, generating muzzle velocities on the order 
     of 840m/s.  The round is steel jacketed & explosive tipped with impact 
     fusing which is preset during manufacture.
     
     The M41 uses electronic pulse action to fire, controlled directly from 
     the trigger.  The internal mechanism, including the rotating breech, 
     is mounted on free floating rails within a carbon-fiber jacket."
     
     
     
Armat M41A Pulse Rifle
TL              12 (at TL 10, reduce damage to 5)
Weapon Length   57/77 cm
Weapon Weight   6.0Kg loaded, 4.1kg empty
Weapon Price    3,265Cr
Magazine Weight 1.8kg loaded, 0.4kg empty
Magazine Price  12Cr

US M309 10*24mm Standard Light Armour Piercing, Explosive Tipped Round
Weight          15g, 1.4Kg for 95
Price           0.9Cr, 86Cr for 95

30mm Grenade
Weight          0.12Kg, 0.48Kg for 4

Grenade         Price
M40 HE          1.2Cr
M38 HEAP        1.8Cr
M60 WP          2.4Cr
M72A1 Starshell 1.2Cr

Weapon                 RoF Dam         Pen    Blk  Mag SS Brst Range IFR
10mm Pulse Rifle HEAP  5   6           2-2-2  3/5  95  1  4    24    -
30mm Grenade HE        PA  C:2, B:10   Nil    -    4   0  -    86    345
             HEAP      PA  C:1, B:3.5  29C    -    4   0  -    86    345
             WP        PA  C:2, B:6    Nil    -    4   0  -    86    345
             Starshell PA  C:0, B:144  Nil    -    4   0  -    86    345
     
     
     Cheers,
     Liam
     
     Liam_McCauley@QSP.co.uk

------------------------------

Date: Fri, 25 Aug 95 12:25:00 PDT
From: David Elrick <Dave.Elrick@ps.co.uk>
To: "traveller%mpgn.com" <traveller@MPGN.COM>
Subject: RE: Relativity and its effects on navigation
Message-ID: <303E23C0@pc136>



tcgny!uunet.uu.net!tcgny!berghold@uunet.uu.net (Peter L. Berghold) said:

> Given that everything in the universe is moving (quickly!) how do you
> calculate where things are in space?  The light you see from a distant 
star
> system may or may not really give you a clue as to its location.  In the
> time it takes for light or other radiation from a star system to get to 
you
> the object has moved from the point it was when the light was emitted. 
 Same
> for your perspective in space.  The place you are observing from is *also*
> moving so that changes the "value" for the observation even more...

> So what is a navigator to do?  This makes navigating in space REAL
> interesting...

We came across this problem on a smaller scale several years ago and this is 
the solution we came up with (it works quite well for your problem too).

Note: I am not an astrophysicist. This was the non-technical 'fix' we came 
up with for our game.

The question that came up was: "Given that the bodies in a star system are 
orbiting the star, how do we know where everything is when we jump 
insystem?"

The answer that we came up with was that everything is moving at an 
observable rate. If we take the known positions of everything in the system 
[or area] at a certain date [say 001/900] and add the calculated rate of 
movement to each body up to the projected date, we come out at a fair 
approximation of the relative positions of everything in the system.

Now you know what the navigation program is calculating while you are 
preparing for jump.

Dave Elrick

 --------------------------------------------------------------------
"Right. How do we get to Regina?"
"We're looking for the large gas giant."
"What does it look like?"
"Well, it's a big red thing on the left."
"Right everybody, we're looking for a big red thing on the left."
 -------------------------------------------------------------------

------------------------------

Date: Fri, 25 Aug 95 12:37:00 PDT
From: David Elrick <Dave.Elrick@ps.co.uk>
To: "traveller%mpgn.com" <traveller@MPGN.COM>
Subject: RE: The ongoing Mertactor Debate
Message-ID: <303E2697@pc136>



Coming from the West of Scotland, I couldn't let this one pass without 
comment.

>>Part of the allure of the frontier would be the wide open spaces. That's
>>why so many colonists came to the Americas initially.  I don't see why it
>>shouldn't apply on an interstellar scale.
>
>Because the cost of shipping emigrants across the Atlantic was low enough
>that even poor people might manage to scrape together enough for the fare.

Most of the Scottish immigrants came to America and Canada because the 
landowners forced them off the land and destroyed their homes to make way 
for sheep and that's where the ships were going.

In fact many landowners 'tried' the people in the so-called 'peasant trials' 
(where they were charged with not attempting to improve their living 
conditions - sad, but true) to justify throwing them off the land.

Many of the Irish immigrants came to America after the failure of the potato 
crop in the hope of escaping the resulting famine.

Hans Rancke then said:

> Hmmm... perhaps we've been arguing at cross-purposes. I thought that these
> RICE papers were supposed to describe things as they might be in the GDW
> universe.

Can we have a decision on this please?


Dave Elrick

 ---------------------------------------------------------------
Dave.Elrick@ps.co.uk
 ---------------------------------------------------------------

------------------------------

Date: Fri, 25 Aug 95 13:04:00 PDT
From: David Elrick <Dave.Elrick@ps.co.uk>
To: "traveller%mpgn.com" <traveller@MPGN.COM>
Subject: RE: Admiralty Manual of Seamanship
Message-ID: <303E2D39@pc136>



lhowie@lrmi.com (Les Howie) said:

> Would you do me the favour of looking up the admiralty definition of a
> cruiser (and light, heavy, etc flavours)?

Pleasure.

Note: This is Crown Copyright and is reproduced here without permission.

<quote>
Cruiser: Cruisers are general-purpose fighting ships whose main function is 
to provide close cover and anti-aircraft support to convoys or carrier task 
groups. They combine hitting power with speed, manoeverability and 
endurance. Their turrets mount medium-calibre guns capable of a high rate of 
fire and are automatically controlled. They can be recognised by their 
turrets and extensive superstructure. They displace from 12,000 to 14,500 
tons, and have an overall length of between 555 and 613 ft.
<end quote>

This is the 1960's definition and is written with RN Cruisers in mind (the 
only RN Cruiser still intact is HMS Belfast which is moored in London and is 
open to the public). Note that this (apart from the dimensions, etc.) is an 
almost exact description of the role of the Type 22 frigate!

> That is another term that has shifted its meaning all over the place in 
the
> last 50 years.

Thereby hangs a tale....

In the late 1960's the then ruling Labour party (under the defence 
secretary, Denis Healy) produced a report which showed that the RAF could 
project airpower to any part of the globe where British interests might be 
under threat (get an atlas out and think about that for a while!). On the 
basis of this, they set in motion the scrapping of the three remaining 
aircraft carriers in RN service and the winding down of the cruiser fleet.

Then, possibly realising their mistake, they authorised the design and 
production of the Invincible class of ships (currently in service) - but 
they were officially to be called 'through-deck cruisers' despite their 
obviously being aircraft carriers!

Dave Elrick

 -----------------------------------------------------------------
Finally, let's lay one common myth to a long-overdue rest. After three 
hundred thousand years of evolution Vargr no longer stick their heads out of 
the window when they're driving.

Dave.Elrick@ps.co.uk
 ---------------------------------------------------------------

------------------------------

End of TRAVELLER Digest 390
***************************
