FT-Sub systems

Heres my first idea for a sub diving/cloaking system (IE-Needs input as
it`s
a first draft, so critisize away<G>).

Subs require a cloaking system at 10% mass of vessil with a minimum of 2
mass and a cost of x10 mass (set at this size to make small subs of
20mass
viable).

Subs require a energy storage system to use thrust or weapons while
submerged. This masses 5% of the ships mass, and can store x10 it`s own
mass
in energy, with a nmin mass of 2 and a cost of x5.

 A sub can maneuver while submerged, at a cost of 10% of it`s mass per
thrust point. This includes thruster pushes. A sub has 3 dive levels,
surface, periscope depth and deep diving. On the surface, the sub is
used as
a normal FT ship, and can recharge the energy storage system at a rate
equal
to it`s thrust rating remaining (even if the thrust/drive is being
used).

 To dive/surface between the different levels requires 1 power point
from
the storage system, and requires the player to specify the turn before
when
diving/surfacing. A sub can exicute a crash dive/surface, at double the
power cost and a roll against the energy system and cloaking device with
a
thresthold roll minus 1 of the present threshold (IE-If undamaged, will
fail
on a roll of 6). A crash dive/surface can be between any levels
(IE-surface
to deep), and doesn`t require it to be decided the turn before, only in
the
turn it`s exicuted movement orders.

If a sub fails it`s dive roll, it stays at the level it was at, but uses
the
energy anyway. A sub is undetectable at deep level diving, and if
detected
before diving to the deep level, will remain detected for 1 turn at the
deep
level.

 A sub can attack other ships at periscope depth with certain weapons,
and
when attacking other ships will always have the first attack (IE-can
attempt
to sink a escort before it can respond, or do a hit and dive attack). A
sub
will remain undetected at periscope depth until it fires, the can be
tracked
by active sensors until it dives deep (thinking different detection
ranges
for different sensor levels).

 If the cloaking device or the energy system is hit by enemy fire, the
enrgy
stored is released, and causes 1 point of dammage per power point per
energy
point.

 The only weapons able to be fired while at periscope depth are P.Torps
(requiring 4 power points to be used), SM`s or missiles (at 1 power
point
per missile fired). Any weapon may be fired at a detected sub at
periscope
depth, although the sub is treated as being 1 range band furthere away
than
it actually is (except for missile/area effect weapons).

Just some rough ideas, a little involved, even though I tried to keep
them
simple.
Awaiting feedback.