ManaSails and GravWood

ManaSails and GravWood
an alternative method of space-faring for Spelljammer

Creator's comments:
        Its always bothered me that the *only* real way to travel through
space requires magic users and priests in abundance.  While I agree that
the SJ setting is more magic-heavy than is "typical" for a D&D setting,
the existing system makes it so that you can't swing a dead cat for hitting
some kind of magic-tosser.  The following additions are my own inventions
for Spelljammer, and should exist side-by-side with helms and what-not.
 One comment before beginning, in my own campaign world, Minor Helms
sell for a mere 10,000gp and Major Helms for 25,000gp, the existing "official"
costs defy all reasonable economics and would result in almost zero spelljamming
traffic as no one would be able to afford a helm...

ManaSails
        ManaSails are a new product of the Arcane, and represent the
latest in Spelljamming technology.  The ManaSail converts ambient magical
energy into motive force in a manner far more efficient than a standard
helm.  Of added benefit is the abolition of the "100 ton limit" in Spelljamming
craft.
        Each ManaSail generates enough motive force to propel 20 spacial
tons of mass at an SR of 1.  Only 1 ManaSail may be attached to a given
mast.  This system works so that if a 30 ton ship with 3 masts is equipped
with ManaSails, it would have an SR of 2 (60 tons of motive power divided
by 30 tons to move).  ManaSails cost 5000gp each.
        Ships may be constructed with "3-dimensional" rigging array (such
as for wind-propelled dirigibles and whatnot) that allow for more masts,
and hence more ManaSails.
        The principle disadvantage to ManaSails is that they are easily
targetted for attack, and are as vulnerable as ordinary cloth to receiving
damage.  The advantage, outside of no longer needing a mage or priest,
is that Spelljamming speed is multiplied by the SR the ManaSails give
the ship.  Theoretically, ManaSails can allow even faster travel between
the spheres.
        Controlling ManaSails and maneuvering requires that the crew
be retrained.  Moving in space is fairly straightforward, but "station-keeping"
or "hovering" in a gravity field is considerably more complex, and can
only be done by an experienced crew, although it is easier if the sails
are connected to "wings" which can be turned "downward" to resist gravity.
 For game-play purposes, treat this as a new proficiency, which defaults
to existing spacemanship -4.

GravWood
        GravWood is mined from the Integral Trees of NivanSpace.  The
Integral Trees are giant trees that spin around the gas torus in the
center of the sphere (from a distance, they look like a spinning integral
sign from calculus, hence the name).  Any object made from this substance
is unaffected by any other gravity field.  For example, a ball made of
GravWood will float in mid-air wherever it is left, if thrown it will
continue in a straight line until it literally runs into something.
Its most practical use is in ship construction, especially when combined
with ManaSails (eliminating the hovering problem explained above.)
        A GravWood vessel will support any amount of weight placed on
it, as long as the amount of GravWood (displacement wise) is more than
50% of the total volume of the object.  In practical terms this means
a ship made from GravWood has no significant encumbrance limit beyond
what can normally fit in its hold.  However, it does mean that a single
piece of GravWood bolted onto the keel is not going to lift the ship.
 GM's discretion as to what works and what doesn't.
        GravWood costs 2x normal hardwood costs, and is treated as softwood
for purposes of armor.  Any ship made of GravWood will get a +1 bonus
to its MC and a +1 bonus to its SR (this doesn't boost the SJ speed of
a ship with ManaSails though!).  Base MC is for softwood (so its 1 better
than that!)  These costs are for ships built/bought in NivenSpace, they
will go up the further the wood has to be transported (obviously.)  Whether
Integral Trees can be grown on other air-worlds is up to the GM.

NivanSpace
        NivanSpace will be detailed in a forthcoming article.  For basics,
its primary unique feature is that its primary is a small blue firebody
that is surrounded by a gas ring (in the 3rd orbital track) which is
populated by various creatures adapted for living in a zero (or low)
g environment.  Most settlements and ports are built into or on the Integral
Trees themselves, since they are large enough to have their own gravity
plane.  For more information, read "The Integral Trees" by Larry Niven.


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