[FT] Underwater was RE: [DS] Underwater...

And now for the FT version, same warnings apply ;)

Cheers

Beth
 >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
Notes: One of the simplest methods would be to just readjust the scale
so 
that 1" now represents something like 25m instead of 100m for DS for 
example, but then the figs really do look huge with regard to the 
ground-scale. Thus, I've opted to go the other way and redefine how the 
weaponry works in the aquatic medium. The following is completely
untested 
and is from someone with no engineering or electronics knowledge (i.e. I

only had my oceanography lessons to draw upon) so feel free to laugh
long 
and loud ;)

FULL THRUST BASED SUGGESTIONS
Full Thrust is the obvious choice for large-scale (as in vessel size) 
marine battles using a GZG product - design ships as usual, but keep in 
mind that they're for oceans not space. I'd suggest the following 
modifications...

Design system:
Paying for streamlining should be rewarded <in this case its
hydrodynamic 
not atmospheric, but the costing is probably just fine as is>, thus
ships 
with full streamlining gain 4 thrust free in addition to that provided
by 
their engines, whereas partial streamlining provides an additional 2 
thrust. All submarines must be fully streamlined.

Weather conditions: Before the game the prevailing weather conditions
and 
currents should be decided upon, the following table is a suggested
range 
of conditions and effects. Roll D6 (or decide by scenario design or by 
agreement of all players)
ROLL	    CONDITIONS	    EFFECTS
1	       Glass		      Top speed is limited to 8xthrust, 
sensor ranges are 1.5x
2	       Normal		     Top speed is limited to 6xthrust,
no 
other effects
3	       Normal		     Top speed is limited to 6xthrust,
no 
other effects
4	       Rough		      Top speed is limited to 3xthrust, 
after movement all vessels drift 1" in the direction of the prevailing 
winds, disposable ordinance has its range reduced to three-quarters
normal, 
for every fighter group launched/landed roll D6 for each fighter in the 
group and on a 6 is the fighter is downed, full streamlining only
provides 
2 extra thrust free, and partial only 1.
5	       Tempest		     Top speed is limited to 2xthrust, 
sensor ranges are halved, after movement all vessels drift 2" in the 
direction of the prevailing winds, disposable ordinance has its range 
reduced to 3/4 normal, fighters may not be used, full streamlining only 
provides 1 extra thrust free, ships without streamlining have their
engine 
rating reduced by 1 (to a minimum of 1), the maximum number of DCPs that

can work on a single repair job is 2.
6		Violent 	       Top speed is limited to 1xthrust,

sensor and weapons ranges are halved, after movement all vessels drift
3" 
in the direction of the prevailing winds, no disposable ordinance or 
fighters maybe used, ships without streamlining have their engine rating

reduced by 1 (to a minimum of 1), the maximum number of DCPs that can
work 
on a single repair job is 1.

Currents:
Currents in an area may also have some effect, one suggestion might be
that 
after movement all ships move 1" in the direction of flow of a strong 
current, 2" if a very strong current.

Land and shallows:
Land is another complication (especially if playing along the coast), 
shoals or shallows could be identified before the game and associated 
penalties and restrictions stated. For instance the following ideas
could 
be used:
DEPTH	       RESTRICTIONS
Land/beach    Can not be passed over, landing is allowed by special
craft
Shoal		  Can only be passed over by surface vessels of mass of
15 
TMF or less
Shallow 	 Can only be passed over by vessels (any type) of mass
of 
45 TMF or less

Vessels that are too heavy to pass over an object hit it instead and are

treated as hitting another vessel that is the equivalent of a
stationary, 
undamaged SDN.

Any vessel that runs aground is potentially hulled, if the collision
causes 
a threshold check then the vessel is immediately hulled and will take an

extra 2 water/flounder damage a turn until a successful damage check (to

patch the hole is made in a repair phase). If the collision does not 
precipitate a threshold check then roll D6 and use the following results
ROLL	 RESULT
1-3	    External damage only, may move off into deeper water and 
continue as normal
4-5	    The vessel is stuck and can not move off the bank for the 
remainder of the battle
6	     The vessel is hulled anyway (takes 2 extra damage a turn
until 
fixed) and is stuck

Collision damage:
For those who are looking for an alternative to the collision damage 
allocation method given in standard FT, the following works well. The 
collision damage inflicted equals the damage die roll multiplied by the 
'speed factor'. The damage die roll is the sum of the rolls on a number
of 
D6, where the number depends on the ship's size:
SIZE			 #D6
TMF 15 or less	    1
TMF 16 to 45	     2
TMF 46 to 105	    3
TMF 106 to 135	   4
TMF 136 to 165	   6
TMF 166 to 195	   8
TMF 196 or more  10

and the 'speed factor' is calculated in the following way:
Hit in the rear arc: Difference in velocity of the two vessels
Hit head on: Sum of the velocities of the two vessels
Hit on the flank (port or starboard): Velocity of other vessel (i.e.
vessel 
takes damage based on the speed of the other vessel hitting it).

Subs:
Due to the fact they work at depth, there are some (potential) 
complications you may want to emulate (this is highly optional). To do 
this, four terms related to the status of the sub have been added:
Shallow - above the thermocline (i.e. easier to detect), for scenarios 
which take place in water that is all shallow then as soon as the sub is

mobile and off the bottom its at 'shallow running'.
Deep - below the thermocline (i.e. at depth so harder to detect), for 
scenarios which take place in water that is all shallow then if the sub
is 
stationary and 'on the bottom' then its 'deep'. Marked by a chit with a 
large D on it. Silent - passive sensors only, trying very hard not to
make 
a noise, marked with a chit with a large S on it. Active - no care is
being 
taken to reduce noise, so may be venting exhaust, firing weapons, using 
active sensors etc.

If the sub has gone to silent running that turn, then when trying to
detect 
it then roll a D6 on a 1 or 2 then you have picked the sub out from its 
background. If the sub has been at silent running for more than 1 turn
then 
you must roll a 1 to detect it. There is a -1 to the roll if the sub is 
currently running shallow. To fire at a sub under silent running you
must 
have detected it first, the only exception is that you may drop depth 
charges at will (until you run out). You don't have to detect 'active'
subs 
before firing at them.

Subs that use active sensors or fire are considered to be active
regardless 
of the status marked down during the orders phase.

Weapons and Firing:
Existing weapons: all as normal, except:
a) 'beams' on surface ships can only target a sub if it is at shallow 
running (and has been detected, if at silent running).
b) non missile weapons used by subs (vs anything) may only fire at close

range <yeah I know they were made for space, but I was thinking more
along 
adopting the design system and generic weapons types rather than
strictly 
bringing down space weapons to the water>

Depth charge: they are placed in the same fashion as standard mines, but

automatically detonate at the end of movement. Any surface vessel
directly 
above it or sub within 6" take a D6 damage, they can not be picked off
by PDS.

Wildlife:
Quite a few whales have been mistaken for vessels over the years, so
large 
marine animals could make a nice counterpoint, target or nuisance factor
in 
a game. Theoretically they could be of any size, though most likely 
destroyer size of less. I'd plot their movement like vessels or just
move 
them randomly (1 D6 for arc they head off in and another 2D6 summed for
the 
distance). They obviously wouldn't have any ranged weaponry (though the
odd 
'dart' or sucker covered arm is possible), but collisions are more
likely. 
More importantly they could become 'decoys', if subs and large wildlife
are 
both being used in the game then in the deployment phase put extra sub 
markers out (with the sub owner recording which are subs and which are 
leviathans), once detected, such that SSD info is garnered, it becomes 
obvious which are which. Further, if there is a large animal within 3"
of a 
sub under silent running which is being fired upon then there is a +1 to

the detection roll and if you roll a 6 you've actually hit the animal
instead.

Swarms of small 'fish', especially if gelatinous can also effect sensor 
info, so you could say that if there is a swarm in the line of fire then

treat as if the target is screened (more a reflection of finding it hard
to 
find them then actually preventing physical damage).

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Elizabeth Fulton
c/o CSIRO Division of Marine Research
GPO Box 1538
HOBART
TASMANIA 7001
AUSTRALIA
Phone (03) 6232 5018 International +61 3 6232 5018
Fax 03 6232 5053 International +61 3 6232 5053