I banged this out this afternoon in relation to my Denizens of the Deep Periphery project. Thought I'd throw it up here and see if it makes sense. Fundamentally, these are intended to be basic rules, so the nuances of ship design and sail plan are pretty much absent.
Basic Sailing RulesOne of the earliest forms of seaborn propulsion, the use of sailing vessels is still reasonably popular across the Inner Sphere and periphery. While the denizens of the developed worlds of the Inner Sphere and near Periphery almost exclusively use such craft for recreation, on the fringes of human occupied space, the humble sailing ship becomes an attractive or even necessary alternative to scarce powered propulsion systems.
These rules include an expansion to the wind rules found on page 57 of tactical operations. In addition to wind direction (determined as normal), players need to also determine wind strength (and by default the base mobility points), either randomly by rolling one six sided die using the following table or by mutual agreement.
Random Wind Strength Table
1-2: Light Wind (3 base MP)
3-4: Moderate Wind (4 base MP)
5-6: Strong Wind (5 base MP)
Sail based movement is regarded as a separate motive system from any other means of propulsion the sailing vessel may possess, and thus cannot be used in concert with powered movement in the same round. The number of movement points available to a sailing vessel depends both on wind strength (as defined above), and direction of travel relative to the direction of the wind. For the sake of authenticity, the following diagram identifies each facing relative to the direction of wind as follows
Running
___
Broad Reach / ^ \ Broad Reach
Close Hauled \_^_/ Close Hauled
Luffed
To determine the available mobility points for the round, apply modifiers based on the hex facing of the unit at the start of the turn as followes.
Running (moving directly with the wind): -1 penalty to the base MP.
Broad Reach: MP is unmodified
Close Hauled: -2 penalty to the base MP.
Luffed (heading directly into the wind): The unit effectively has 0 movement points for the round, but may still execute a single facing change at no cost.
This final MP total may be spent as normal for a typical displacement hull water craft regardless of the facing changes made during the turn (a vessel could thus briefly travel directly into the wind as long as it starts its round on a facing that grants it mobility points). All such movement is treated as cruising movement for purposes of attacker movement modifiers.
Because the art of squeezing ever last bit of performance from a sailing craft is inherently more complicated than the operation of a conventional power plant, at the start of each round a sailing crew may attempt a driving skill roll to improve performance. On a success, the vessel gains a number of additional MP for the round equal to their margin of success divided by 3 (up to an additional 2 mobility points). On a failure, however, the vessel loses mobility points at the same rate, which may reduce the vessel's movement all the way to zero if they fail badly enough. If the vessel starts the round Luffed, it still cannot spend any bonus MP to move into another hex, but may spend them on additional facing changes.
The various storm options (page 61 of tactical operations) should not be used without the consent of all parties. If all parties agree, Light and Moderate Gales are treated as heavy wind (as well as imposing the same modifiers described in Tactical Operations. Sailing vessels are treated as WiGEs for purposes of driving/piloting modifiers). Stong Gales and Storms provide the same base MP as Strong Winds, along with the same penalties listed in their entry in Tactical Operations. In addition, at the end of each round in Strong Gale or Storm conditions, the player must role 2d6 for each sail powered vessel under their control. On a role of 12, immediately roll again on the motive system hit table and apply the resulting affect to the sail system. Apply a -2 roll modifier if the vessel is not currently actively using its sails for movement. Remember that any motive damage suffered by the sails is not applied to any other propulsion system the craft may possess.
In combat, damage against a sailing vessel is resolved as a standard displacement hull naval unit, with some considerable modifiers. Sailing vessels, at least the small ones covered by these rules, cannot have a turret. This is instead replaced by the Rigging location, a generic catchall to cover the sails, masts, and riggings that allow the sailing vessel to function. In game terms, this location functions largely like the rotors of a VTOL, with the same resistance to damage and armor limit. In addition, any potential critical hits against the rigging are disregarded. However, any damage that strikes the Rigging automatically requires a roll on the motive system damage table with a +3 modifier. Once again, any motive system damage applied to the sails affects the vessel only when it is using those sails, just as any motive system or critical damage to other locations that affect movement only penalize any conventional propulsion system the vessel may carry. If the vessel has no auxiliary power plant, treat any engine or fuel tank critical hits as crew stunned results.
For construction purposes, sails and rigging are treated as a chassis modification available to any small or medium naval support vehicle (large naval support vehicles are outside of the scope of these rules), and may not be combined with the submersible or hydrofoil modifications. The Sails chassis modification has a minimum tech level of A and applies a X2 modifier to chassis mass.
