Wind Force

Beaufort Scale

Wind Force describes the strength of the wind as it affects the movement of ships in naval combat, pressure upon the rigging and, in extreme cases, the vessel's immediate safety. For game purposes, wind force is divided into grades, each describing the practical effect of the wind upon ships and the surrounding sea. __TOC_ These grades are expressed by the shown Beaufort scale, which although anachronistic for D&D, is nevertheless too useful a tool to ignore. The images make clear what can be observed and the visual effects upon the sea and structures. In ship manoeuvring, as wind force increases, the sea rises, steering becomes more demanding and the risks of collision, fouling, falling overboard and physical damage to the ship's structure become more severe.

Wind Force on Ships and Battle

Most engagements will take place when the middle grades of wind force occur, this being force 3 to force 6. This wind gives enough power for ships to manoeuvre effectively, but not so much that weather dominates the battle. Distance can be gained best by small ships which move more easily through water, allowing them to approach, withdraw, bring weapons to bear or attempt boarding.

Less wind force, between 0 and 2, leaves ships both slow and helpless. In such winds, however, triremes become much more dangerous, while sailing ships are more dependent upon being towed. It is not unheard of for a ship to put out boats and physically tow themselves close enough to an enemy to engage in battle, but it is a rare happenstance.

Greater wind force of 7 to 9 causes the sea to rise so that steering becomes more demanding and the risks of collision, fouling, and failure to manoeuvre become greater; larger, heavier ships do better in these situations, because they are tossed less than small, light vessels. Such creates opportunities for very large ships to pass by and attack an unstable, smaller vessel, or even outrun one, as in rough seas the larger vessel is able to manage itself better.

Extreme wind forces, greater than 10, produce survival conditions. Naval combat is impossible as the crew and all aboard are busy preserving the ship and avoiding the possibility of a wreck.

Wind Effects on Ship Handling

Best possible ship speed for a 100 ton vessel under full sail

Wind Force	Ship's Headway	Hexes per round
		Ship Hexes	Combat Hexes
0	Becalmed; no headway	0	0
1	Barely moving; steerage doubtful	0.4	2
2	Slow movement; sail draws weakly	1.2	6
3	Reliable movement begins	2.4	12
4	Good sailing wind	4	20
5	Strongest easily managed sailing wind	5.2	26
6	Ship pressed; greater movement, but lessening of manoeuvring ability	5.6	28
7	heavy wind; handling worsens	4.8	24
8	dangerous wind; sail must be reduced	3.6	18
9	severe wind; movement is unstable	2.4	12

The following outlines describe the general limits placed upon a ship’s manoeuvrability at each wind force from 0 to 9. These limits assume a 100-ton vessel moving under the best possible conditions for that force, as shown in the table above. They do not replace the movement rules, but provide guidance for how readily a ship answers the helm, corrects its position, avoids danger or attempts close action while moving under that wind.

Force-0: Becalmed and cannot manoeuvre under sail. The ship may drift with current or tide, but it cannot turn, close, withdraw, bring weapons to bear by sailing movement or recover from a poor facing by use of the wind. Any change of position must come from oars, towing, anchoring, warping, current or outside force.

Force-1. Barely has steerage. The ship may change facing only slowly, and any ship turn should be treated as uncertain or delayed unless assisted by oars or towing. The vessel cannot rely on sail to evade, pursue or correct its position quickly, and may fail to answer the helm in time to avoid collision, fouling or loss of advantage.

Force-2. Weak but usable movement. The ship may manoeuvre under sail, but slowly, with ship turns requiring more room and more time than usual. The vessel can begin to seek position, but it cannot readily close to engagement, escape a determined oared vessel or recover quickly from being placed badly against the wind.

Force-3. Reliable manoeuvre begins. The ship answers the helm in a useful manner and may turn, close, withdraw or bring weapons to bear with ordinary care. Manoeuvres are still deliberate rather than sudden, and the vessel remains vulnerable to poor orders given during the previous ship turn.

Force-4. Manoeuvres well. The ship has enough headway to answer the helm cleanly, while remaining under easy control. Turns, changes of position and attempts to gain the weather or close with an enemy may be made without special penalty, assuming the ship is properly crewed and undamaged.

Force-5. The ship reaches its strongest easily managed sailing condition. It may use its speed aggressively while still retaining good command of the helm, sails and rigging. This is the best general condition for combat manoeuvre, pursuit, withdrawal, boarding approach or bringing deck weapons to bear.

Force-6. The ship is pressed. It may gain greater movement, but its manoeuvring ability begins to lessen. Turns of greater than 30° cannot be made; D crews cannot back sail or succeed in grappling enemy ships; attempts to avoid fouling are penalised (qv.) depending upon the crew quality. Any crew attempting to shorten sail or back sail will require twice the normal time to do so.

Force-7. Handling worses. The ship remains capable of movement, but handling worsens noticeably. Turns of greater than 30° cannot be made; C and D crews cannot back sail effectively during the present ship turn; D crews cannot succeed in grappling enemy ships; attempts to avoid fouling are further penalised. Any crew attempting to shorten sail or back sail will require thrice the normal time to do so.

Force-8. Similar conditions to force-7 above, except that only A crews may attempt grappling. Backing sail is no longer feasible and shortening the sail requires four times the normal length of time.

Force-9. Similar conditions to force-7 above, except that boarding approaches, backing the sail or grappling cannot be performed. Fouling may permit boarding. Ships cannot be unfouled unless a cessation of conflict occurs and both ships attempt to perform the necessity. Shortening the sail requires five times the normal length of time.

Hurricane

See also,
Logging Movement (naval)
Movement Allowance (naval)
Movement Notation
Naval Combat
Ship's Attitude
Wind Effects on Movement