Well, Jeff has made a good point. Several actually.
In my previous posts, I just went with the canon assumptions on mass (Never
bothered to think about it).
But if it boils down to 1 Marine = 4 Spaces = roughly 1/6 mass = 1/6 of
100 Mt.... well that seems kind of gross. Even if you give the guy his kit
plus a stateroom, 16 Mt does seem pretty horrendous. Yes, you have to include
kitchesn and the like, but as I recall in MegaTraveller (and their tonnage was
disp based rather than mass based), they alloted 4 tons for a stateroom that
could be single or double bunked. So if you double bunked your marines, you
could get a Marine for two tons. Awake. That's (if mass and disp were
equivalent measures) about 8 * as many marines on a Traveller ship.
So the initial figures do seem to indicate that the MT figure is....
unappealling.
For those who like cannon, and varying rules versions (FB, MT), then stick
with the standard rule.
But perhaps it is a figure worth examination.
We know a Marine as a fish stick should take up some amount of space. Let's
start there. I'd say 1 Mt. that's 1000kg. That includes our 150 kg Jarhead, a
250 kg cryoberth, and 200 kg worth of support machinery and still leaves room
for 400 kg of kit, which is quite a bit.
So that being said, 1 Marine shipped as a fish stick would take up 1
DS/SG cargo space, which (in our model) would be 1/100th of an FT Mass.
So now, rather than putting 25 Jarhead-brand Freezersticks into 1 Mass,
we could put 100. That's an improvement.
If we extended this to the *live* version, we'd then get 25 live Jarheads in
that same 1 Mass, rather than 6. I'd call that a quantum leap. Now that would
mean about 4 Mt per Marine. What would that be? I'd guess 2 Metric Tons worth
of staterooms, sanitary facilities etc, 0.5 Mt
worth of space devoted to common workout/living areas (which means about
the size (mass) of 4 staterooms in an 8 man squad), and 500 Kg devoted to
personal kit, leaving 1000kg for vehicle transportation (or 8000kg per squad).
That seems quite reasonable.
So now, to move a division of Jarheads with some basic transport (I'm not
talking an armoured division here, just 5K of warm bodies), instead
of requiring about 200 Mass as FreezerSticks and 800 Mass as body-temp
ambulatory bodies, you now only require 50 Mass and 200 Mass. These are far
more practicable and pragmatic values for moving large forces through space.
So using a 1 Mass = 100 CS seems far more palatable. That also means,
following the 8/5 rule for vehicles transporting other vehicles, that in
that 100CS you can put about 65 DS2/SG2 spaces worth of vehicles (and in
theory, store them full of stuff if they were trucks or the like, but I'm not
going there just now). That is the equivalent of 4 size 3 Medium BTs. Or the
better part of 3 Heavy (size 5) BTs. So now moving our armoured regiment of
150 various class MBTs now takes maybe 50 Mass. That too is much more
palitable.
So, I guess if you feel compelled to stick to the Canon, all is well and good.
But I'd *HEARTILY* suggest that St.Jon the Cleric In His Own Religion think
about an FB2 conversion factor that matches this. Because.... this level of
carrying capacity makes some of the large scale wars discussed in the GZG
timeline AND all the numerous small scale conflicts almost practical. It makes
the movement of an Army Group (25 divisions lets say) something that might
take 5000 Mass.... admittedly a gross figure but doable with good cause... as
opposed to 20,000 Mass which is way more grotesque.
Jeff, you've sold me. I'm a convert.:)
Jeff said lots of smart stuff, to which I reply:
Okay, I'd buy splitting out kit from Jarheads. Now, I suppose we could easily
rationalize 1000 kg if we count powerplant and fuel for same and revival
centres and all that kind of stuff that would go with the Jarhead brand
freezerstick.
I can see a desire to keep kit separate (esp supplies) from the Jarhead.
But I'm trying to keep some perspective on the existent designs - if we
said each soldier has his basic kit load (personal weapon, body armour, etc),
we only really have to just up multiply the number of Marines in existing
designs, not totally refigure.
Andrew raised a good point about awake marines. I assume the 4* mass helps to
account for things like extra supply, life support, etc. Since you don't have
to deal with this stuff for crew, lets no think to hard about it for soldiers.
I did have one problem with Jeff's post on vehicles. His mass ranges
overlapped! Add to which the 8/5ths rule doesn't reflect a "mass" issue,
but a "space" issue I think.
How about this: A vehicle has X capacity points (5* size class normally, but
some oddball designs are out there).
By cannon, that would take up 8/5 the space it internally uses. It's
this space that really matters.
So, if we have 4 DS/SG spaces = 1 Cargo Space, and 25 CS = 1 Mass = 100
DS Spaces = 100 t. So therefore a size 5 MBT would take up the equivalent of a
size 8 vehicle, which would be 40 DS capacity points, or the equivalent of 40
metric tons. That's about 80,000 kg. That's heavy. But, in the future, with
aligned superdense armours and VERY thick armour, VERY heavy guns, and very
powerful powerplants for propulsion, this might not be totally out of whack
for a class 5 tank. And anyway, it isn't just the tank, it's the tank plus
it's associated storage decking. So I think you
should preserve the 8/5ths rule.
Exception: Vehicles shipped "packed" (some assembly required) might be shipped
for their size in DS spaces. Of course, you can't "drive" it off
the other side. It probably will take a day to re-assemble (or some
period of time depending on type of vehicle). And this must be done on the
ground! This is the "car transporter" method. It can be used to move
strategic stockpiles, but not on a RO-RO assault transport.
So, if you want to keep special (heavy) kit separate, like PA, vehicles, heavy
weapons, etc., how had you in mind to calculate this mass? From your TO&E?
And supplies, what figures had you in mind for covering expendables
(everything from medical supplies, ammo loads, food, water, blood, pay stubs,
playing cards, etc....) for the troops?
I'd say that someone paying 4 cargo spaces to ship their guy (4 Mt)
shouldn't have to feed them while on the ship - you don't have to feed
crew members nor normal boarding parties. So the only supply you need worry
about is downwell supply.
I had some "guestimates" for expendibles for a standard mechanized infantry
force:
Low tempo operations: 10 kg/man/day
Mid tempo operations: 20 kg/man/day
High tempo operations: 40 kg/man/day
This is a generic way to account for things like everything from rations,
basic ammo loads, etc to TP and field message pads. You don't
want to go too detailed here - it'll be gross.
I think an easy way to do it would be to define your standard troop types:
Infantry (Foot) (IF) Infantry (Mech) (IM) Powered Armour (PA) Armour (ARM) Air
(AIR) Artillery (ART) Support (SUP)
We could take some educated guesses at their supply requirements:
Tempo Low Med High
vs. Troop IF 5 10 20 IM 10 20 40 PA 10 20 40 ARM 20 40 80 AIR 25 50 100 ART 20
40 80 SUP 15 30 60
Now, this is hardly a panacea of everything, but it will certainly cover
a reasonable weight of supplies in KG/day.
So, we have the base weight of our marine (1 DS space), plus his personal kit.
Then we have an additional (if he's mech infantry) 20 kg *
however many days of supply we think he needs (I'd say a month minimum -
600 kg). Add in the space consumed by any vehicles. I'd say treat PA as a 1
space vehicle, which can be stored for 1 capacity point. This includes a
locker and some basic spares. IWs, treat as same class vehicle. Bikes and such
get treated as size 0.5 vehicles.
An example might be instructive: I have a company to build a transport for.
The company consists of 200 men in 5 40 man platoons. Four of these are
mechanized infantry, one is support. So, I have 200 men, which is 2 mass as
cryosleepers. But I want these guys capable of operations so I keep them in
berths so 200 men is 8 mass. They have 4 APCs per mech platoon, and the APC is
a size 3 vehicle (15 capacity points). So we have 60 cap points per platoon *
4 platoons
or 240 capacity points. Stored RO-RO style, this needs the 8/5ths
conversion factor. That's 384 capacity points - call it 4 mass and we've
got room for two class one vehicles additional (jeeps for the command staff).
The support guys have the equivalent of another 60 points of
vehicles - another mass. So we have 8 mass in troops (awake) and 5 mass
in vehicles (RO-RO). We need supplies for this unit - the infantry are
IM and the support guys are just that. We decide we want 30 days supplies for
normal tempo operations. That is 20 kgs * 160 guys * 30 days or 96,000 kg. Add
to this supply for 30 days for the support group
of 40 - 30 kgs * 40 guys * 30 days for a total supply weight of 132,000
kg. Or more than 1 mass. So call it 2 mass, put in 200,000 kg of supply, and
that should be supplies for 45 days of normal tempo ops (4400 used per day).
This of course would be 90 days of low intensity ops or 22.5 days of high
intensity ops.
So, all told we have 2 mass for supplies, 5 mass for vehicles, and 8 mass for
humans. So that is 15 mass. Now, this doesn't account for ortillery support
modules, nor air support or transport to the surface (you could streamline the
troopship or install shuttles). But that gives you a good base.
Now, this is a pretty simple example (as compared to some you could construct)
but it demonstrates a reasonable approach to the problem.
Remember the basic cannon of Ground Zero Games. Keep it Simple! That's why I'd
stay with the 1 Full Thrust MAss is equal to 25 CC. A size 5 vehicle can be
stored in a 1 mass storage facility and be ready to go.
Jeff Lyon made some good points:
Post 1:
Well, I've been looking at the rulebooks again, as well as trying to adapt
the conversion rates I was suggesting to both real world and sci-fi
examples and the numbers still seem to have some problems. In particular, the
tonnage rates for infantry and smaller vehicles both still seem too high.
At this point, I'd be inclined to suggest the following conversion:
1 DS2/SG2 capacity point = 500 kg (0.5 metric tonnes)
So here are my latest suggestions for conversion rates:
1 FB Mass = 100 metric tonnes = 200 DS2/SG2 capacity points
Vehicles require (size x8) capacity points plus (size x4) for each level of
regular armor or (size x6) for each level of reactive or ablative armor. (Note
that when using this conversion rate small, lightly armored vehicles work out
to about half the mass described in my earlier post, but because of the higher
rates for armor, the larger and more heavily armored vehicles are still quite
massive.)
-----------------------------------------------------
** Okay, let's try a couple of examples I use.
Size 3 APC with twin DFFG/1 and twin SAW. Armour 2. You are telling me
that effectively this would take 8x3 = 24 + 2x4 = 8 -> 32 points
total. Fine and good. This is about 16 Metric Tons or 35,300 pounds. Size 5
MBT with level 5 armour. This would take 60 capacity points. This is about 30
Metric Tons or 66,000 pounds. Size 1 hoverjeep. Armour 1. this would be 12
capacity points which is about 6 Mt, or about 13,200 lbs. A tad on the heavy
side. If it was soft skinned, you've got 8 capacity points, 4 Mt, and about
8800 lbs. which is still too heavy.
How about this: We're trying to hit roughly the following numbers:
Tank - 20K to 80K kgs. (the average being 35-50K kgs)
Jeep - 1K to 3K kgs.
APC - 12K to 20K kgs. (size 3)
What conclusions can we draw? Vehicle masses do not increase linearly with
size!
I'll have to try some math to fit something to this model. A bunch of data
points and some fooling about ought to yield a better model. If it does, I'll
post it.
--------------------------------------------------------
Long-range transport of personnel requires 4 capacity points per
person if in quarters or 1 capacity point per person if in cryo.
Long-range transport of infantry kit requires 1 capacity point per
element
for rifle, assault, or lightly-equipped (4-5 man) engineer teams; 2
capacity points per element for APSW, fire designation, anti-armour,
local
air defense or heavily-equipped (2-3 man) combat engineer teams.
Long-range transport of powered armor kit requires 8 capacity points
per element. Personal kit for vehicle crews can be assumed to be stowed aboard
their vehicles or kept in quarters.
** You should be able to use in-vehicle space to store kit to cut down
on wasted space.
Post 2:
50 persons/mass unit - Crowded conditions (not uncommon for troop
transports); officers share a double occupancy cabin, ratings or troops are
quartered four to a cabin (probably with two-shift "hot bunking").
** Is hot bunking an option for ships that have to manoevre? You need a crash
frame for all crew members and they can't be hot bunked.
100 persons/mass unit - Very crowded conditions ("normal emergency"
occupancy); all cabins and some common areas are utilized at maximum
occupancy and a strict rotation schedule is used for "hot-bunking",
galley access, etc. Ships at such crowded levels would not normally engage in
combat or high-G maneuvers.
** Same comment as my last.
200 persons/mass unit - Life boat conditions (extreme emergency
occupancy); all available space (cabins, common areas, passageways) would be
utilized. Life support would be strained to the limit. Food, water and access
to all ship's facilities would be rationed. Such crowded conditions should be
considered a hazard to the health and safety of all aboard. As none of the
redundant life support equipment can be taken off-line for routine
maintenance, long-term occupancy at these levels may result in a
catastrophic breakdown of life support systems.
** High G manoevres would kill people in this crowding level.
A ship with a "very strong (50%) level of hull integrity MAY (at designer's
option) have sufficient mass devoted to crew quarters to satisfy the "luxury"
level of occupancy for the ship's crew and up to one element
(5
capacity points) of ship's marines per crew factor.
** And if not?
BTW, good work Jeff. Other than not being happy yet with your formula for
vehicle weighting, I'm pleased enough.
> Date: Tue, 12 Oct 1999 18:10:42 -0400
Thanks. And thanks for the continued good feedback. Comments follow.
> Post 1:
> At this point, I'd be inclined to suggest the following conversion:
> From some of your comments below, this may need to be clarified to
1 DS2/SG2 capacity point = up to 500 kg (0.5 metric tonnes) or
a volume normally rated for carrying a cargo of similar mass.
The idea being that 500 kg of dense, heavy junk will fill a certain volume,
(say 0.5 cubic meters or whatever). If that same volume is filled with less
dense stuff, then you've still used up the given capacity, but the vehicle's
fully loaded mass is lighter than "average" (whatever that
is).
> So here are my latest suggestions for conversion rates:
Note that EACH level of armor increases the weigh of the vehicle by (size x4)
capacity points.
> - -----------------------------------------------------
See above. You've only counted the first level of armor. Should have been:
8x3 (=24) + 2x2x4 (=16) = 40 points/20 metric tons/~44,000 lbs.
> Size 5 MBT with level 5 armour. This would take 60 capacity points.
Again, see above. This is just one level of armor. Should be:
8x5 (=40) + 5x5x4 (=100) = 140 pts./70 metric tons/~154,000 lbs.
> Size 1 hoverjeep. Armour 1. this would be 12 capacity points which
Agreed, but see comments below.
> If it was soft skinned, you've got 8 capacity points, 4 Mt, and
And while we are at it, 500 kg is also too much for a leg trooper and kit.
Probably by a factor of three or so.
As shown in these examples, you're right; a direct capacity points to tonnage
conversion doesn't quite cover all of the bases. This is an example of where
one may need to consider a volume component as well; in other words, if an MBT
is 30 times the mass of a jeep or 1000 times the mass of a leg trooper with
full kit, that does not necessarily mean that
you can fit 30 jeeps or 1000 leg troopers into an MBT-sized dropship.
Not in ready to use condition, anyway.:)
So we might want to say that the minimum capacity requirement (size x8
points) for small, light-weight vehicles does not necessarily mean that
they are massing 4 metric tons, but that they are being alloted a volume of
cargo space that would normally be used to carry up to 4 metric tons of other
cargo.
Likewise, our leg troopers with full kit don't actually weigh 500 kg each, but
are instead taking up a volume of space in your APC that could have been
filled with 500 kg of armor, weapons, fuel, ammo or electronics. Or in the
case of transport vehicles could have carried 500 kg of water cans, ammo boxes
or whatever.
> What conclusions can we draw? Vehicle masses do not increase
Yup. Noticed that too. Unfortunately, the capacity requirements from DS and SG
do. Therefore something's got to give; one must either shrug off the
inconsistencies in favor of the simple, linear calculation given as
canon or adopt a different, non-linear formula for calculating vehicle
mass.
The approach I took was intended as a compromise; instead of just
completely ditching the 8/5ths rule for vehicles, I tried to keep it as
the minimum amount of capacity that a vehicle of a given size would require
and
use the armor level time vehicle size to give the non-linear effect that
would seem to more closely model what we see in the real world.
Also, instead of either completely ditching the vaguely defined capacity
points used in DS2/SG2 in favor of something more concrete or continuing
the MT model which requires yet another vague unit of measure (cargo spaces)
as an intermediate step for converting capacity points to FB mass units, I
wanted to have a relatively simple, generally applicable conversion rate from
one to the other.
> I'll have to try some math to fit something to this model.
I've glanced through the material at the URL you posted later, but have not
examined it at length. I'll try to comment in more detail when I've looked at
it more closely, but the first thing I did notice was the note at the top:
"1 Mass = 100 Mt = 200 cargo units (which is not I repeat NOT necessarily an
SG2 cap point)"
As I said in my comments above, I think I'd rather have a direct capacity
points to mass units conversion than yet another unit of measurement that is
"not necessarily" one or the other.
For vehicles, I'd like to keep as much of the canon rules and the 8/5ths
ratio as possible. What I intended was for a vehicle to still have a maximum
internal capacity of (size x5) but to require at least (size x8)
+
(armor level x size x some factor) capacity points to be carried inside
another vehicle. To my mind, this is most often going to be an issue with
dropships, which are limited both by their interior volume and their lift
capacity.
Note that this means the 8/5ths ratio will only work one way; an
extremely
massive, heavily-armored vehicle cannot carry 5/8ths its own weight as
internal capacity... it is still limited to an internal capacity of (size
x5). Or put another way, the 8/5ths ratio describes the minimum
capacity requirement for a vehicle designed to carry it; for heavily armored
vehicles, the ratio may actually be 28/5ths or more.
<snip>
> Personal kit for vehicle crews can be assumed to be stowed
Good point, as a logical extension of the "mounted up" rule from MT and my
comment above regarding personal kit for vehicle crews you should also be able
to do this for the kit of leg elements normally assigned to a vehicle.
> Post 2:
> ** Is hot bunking an option for ships that have to manoevre?
Good question. Let's assume that with this level of crowding, when the ship
goes to general quarters, everyone on board will either be at a duty station
that has a crash frame or will be in quarters and that the bunks are designed
to double as a crash frame.
> 100 persons/mass unit - Very crowded conditions ("normal
And let's assume that at this level of crowding there are not enough crash
frames to go around; hence the restriction on high-g maneuvers and
combat.
I'd assume certain number of passengers and crew are expected to be using
common areas (galleys, gym, etc.) in order to stay out of the way of both
the on-duty and off-duty shifts and that they would not have access to a
crash frame unless a) they climb into a lifepod or b) every compartment has
some sort of rudimentary crash frame that folds down out of the wall or
something. (I'm suddenly visualizing a piece of emergency gear; some sort of
hammock thingey anchored to an eyehook in each of the eight corners of the
room by some sort of bungie cords. Might save someone's neck. Might
not.)
> 200 persons/mass unit - Life boat conditions (extreme
> ** High G manoevres would kill people in this crowding level.
Agreed.
> A ship with a "very strong (50%) level of hull integrity MAY
I'd say this depends on the design philosophy of the fleet; might be opulent
suites for the senior officers, quarters for a larger than average crew or
marine complement, larger common or rec areas, extra redundant systems, more
science labs or some combination of some or all of the above... whatever seems
appropriate to the background.